sfrench/cifs-2.6.git
12 months agos390/vdso: don't clear PG_reserved
David Hildenbrand [Tue, 5 Mar 2019 23:47:10 +0000 (15:47 -0800)]
s390/vdso: don't clear PG_reserved

The VDSO is part of the kernel image and therefore the struct pages are
marked as reserved during boot.

As we install a special mapping, the actual struct pages will never be
exposed to MM via the page tables.  We can therefore leave the pages
marked as reserved.

Link: http://lkml.kernel.org/r/20190114125903.24845-3-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Suggested-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Souptick Joarder <jrdr.linux@gmail.com>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agoagp: efficeon: no need to set PG_reserved on GATT tables
David Hildenbrand [Tue, 5 Mar 2019 23:47:07 +0000 (15:47 -0800)]
agp: efficeon: no need to set PG_reserved on GATT tables

Patch series "mm: PG_reserved cleanups and documentation", v2.

I was recently going over all users of PG_reserved.  Short story: it is
difficult and sometimes not really clear if setting/checking for
PG_reserved is only a relict from the past.  Easy to break things.  I
guess I now have a pretty good idea wh things are like that nowadays and
how they evolved.

I had way more cleanups in this series inititally, but some
architectures take PG_reserved as a way to apply a different caching
strategy (for MMIO pages).  So I decided to only include the most
obvious changes (that are less likely to break something).  So the big
chunk of manual SetPageReserved users are MMIO/DMA related things on
device buffers.

Most notably, for device memory we will hopefully soon stop setting
PG_reserved.  Then the documentation has to be updated.

This patch (of 9):

The l1 GATT page table is kept in a special on-chip page with 64
entries.  We allocate the l2 page table pages via get_zeroed_page() and
enter them into the table.  These l2 pages are modified accordingly when
inserting/removing memory via efficeon_insert_memory and
efficeon_remove_memory.

Apart from that, these pages are not exposed or ioremap'ed.  We can stop
setting them reserved (propably copied from generic code).

Link: http://lkml.kernel.org/r/20190114125903.24845-2-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm: rid swapoff of quadratic complexity
Vineeth Remanan Pillai [Tue, 5 Mar 2019 23:47:03 +0000 (15:47 -0800)]
mm: rid swapoff of quadratic complexity

This patch was initially posted by Kelley Nielsen.  Reposting the patch
with all review comments addressed and with minor modifications and
optimizations.  Also, folding in the fixes offered by Hugh Dickins and
Huang Ying.  Tests were rerun and commit message updated with new
results.

try_to_unuse() is of quadratic complexity, with a lot of wasted effort.
It unuses swap entries one by one, potentially iterating over all the
page tables for all the processes in the system for each one.

This new proposed implementation of try_to_unuse simplifies its
complexity to linear.  It iterates over the system's mms once, unusing
all the affected entries as it walks each set of page tables.  It also
makes similar changes to shmem_unuse.

Improvement

swapoff was called on a swap partition containing about 6G of data, in a
VM(8cpu, 16G RAM), and calls to unuse_pte_range() were counted.

Present implementation....about 1200M calls(8min, avg 80% cpu util).
Prototype.................about  9.0K calls(3min, avg 5% cpu util).

Details

In shmem_unuse(), iterate over the shmem_swaplist and, for each
shmem_inode_info that contains a swap entry, pass it to
shmem_unuse_inode(), along with the swap type.  In shmem_unuse_inode(),
iterate over its associated xarray, and store the index and value of
each swap entry in an array for passing to shmem_swapin_page() outside
of the RCU critical section.

In try_to_unuse(), instead of iterating over the entries in the type and
unusing them one by one, perhaps walking all the page tables for all the
processes for each one, iterate over the mmlist, making one pass.  Pass
each mm to unuse_mm() to begin its page table walk, and during the walk,
unuse all the ptes that have backing store in the swap type received by
try_to_unuse().  After the walk, check the type for orphaned swap
entries with find_next_to_unuse(), and remove them from the swap cache.
If find_next_to_unuse() starts over at the beginning of the type, repeat
the check of the shmem_swaplist and the walk a maximum of three times.

Change unuse_mm() and the intervening walk functions down to
unuse_pte_range() to take the type as a parameter, and to iterate over
their entire range, calling the next function down on every iteration.
In unuse_pte_range(), make a swap entry from each pte in the range using
the passed in type.  If it has backing store in the type, call
swapin_readahead() to retrieve the page and pass it to unuse_pte().

Pass the count of pages_to_unuse down the page table walks in
try_to_unuse(), and return from the walk when the desired number of
pages has been swapped back in.

Link: http://lkml.kernel.org/r/20190114153129.4852-2-vpillai@digitalocean.com
Signed-off-by: Vineeth Remanan Pillai <vpillai@digitalocean.com>
Signed-off-by: Kelley Nielsen <kelleynnn@gmail.com>
Signed-off-by: Huang Ying <ying.huang@intel.com>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Rik van Riel <riel@surriel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm: refactor swap-in logic out of shmem_getpage_gfp
Vineeth Remanan Pillai [Tue, 5 Mar 2019 23:46:58 +0000 (15:46 -0800)]
mm: refactor swap-in logic out of shmem_getpage_gfp

swapin logic can be reused independently without rest of the logic in
shmem_getpage_gfp.  So lets refactor it out as an independent function.

Link: http://lkml.kernel.org/r/20190114153129.4852-1-vpillai@digitalocean.com
Signed-off-by: Vineeth Remanan Pillai <vpillai@digitalocean.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Kelley Nielsen <kelleynnn@gmail.com>
Cc: Rik van Riel <riel@surriel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm/vmscan.c: remove 7th argument of isolate_lru_pages()
Kirill Tkhai [Tue, 5 Mar 2019 23:46:55 +0000 (15:46 -0800)]
mm/vmscan.c: remove 7th argument of isolate_lru_pages()

We may simply check for sc->may_unmap in isolate_lru_pages() instead of
doing that in both of its callers.

Link: http://lkml.kernel.org/r/154748280735.29962.15867846875217618569.stgit@localhost.localdomain
Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm, mempolicy: fix uninit memory access
Vlastimil Babka [Tue, 5 Mar 2019 23:46:50 +0000 (15:46 -0800)]
mm, mempolicy: fix uninit memory access

Syzbot with KMSAN reports (excerpt):

==================================================================
BUG: KMSAN: uninit-value in mpol_rebind_policy mm/mempolicy.c:353 [inline]
BUG: KMSAN: uninit-value in mpol_rebind_mm+0x249/0x370 mm/mempolicy.c:384
CPU: 1 PID: 17420 Comm: syz-executor4 Not tainted 4.20.0-rc7+ #15
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
Call Trace:
  __dump_stack lib/dump_stack.c:77 [inline]
  dump_stack+0x173/0x1d0 lib/dump_stack.c:113
  kmsan_report+0x12e/0x2a0 mm/kmsan/kmsan.c:613
  __msan_warning+0x82/0xf0 mm/kmsan/kmsan_instr.c:295
  mpol_rebind_policy mm/mempolicy.c:353 [inline]
  mpol_rebind_mm+0x249/0x370 mm/mempolicy.c:384
  update_tasks_nodemask+0x608/0xca0 kernel/cgroup/cpuset.c:1120
  update_nodemasks_hier kernel/cgroup/cpuset.c:1185 [inline]
  update_nodemask kernel/cgroup/cpuset.c:1253 [inline]
  cpuset_write_resmask+0x2a98/0x34b0 kernel/cgroup/cpuset.c:1728

...

Uninit was created at:
  kmsan_save_stack_with_flags mm/kmsan/kmsan.c:204 [inline]
  kmsan_internal_poison_shadow+0x92/0x150 mm/kmsan/kmsan.c:158
  kmsan_kmalloc+0xa6/0x130 mm/kmsan/kmsan_hooks.c:176
  kmem_cache_alloc+0x572/0xb90 mm/slub.c:2777
  mpol_new mm/mempolicy.c:276 [inline]
  do_mbind mm/mempolicy.c:1180 [inline]
  kernel_mbind+0x8a7/0x31a0 mm/mempolicy.c:1347
  __do_sys_mbind mm/mempolicy.c:1354 [inline]

As it's difficult to report where exactly the uninit value resides in
the mempolicy object, we have to guess a bit.  mm/mempolicy.c:353
contains this part of mpol_rebind_policy():

        if (!mpol_store_user_nodemask(pol) &&
            nodes_equal(pol->w.cpuset_mems_allowed, *newmask))

"mpol_store_user_nodemask(pol)" is testing pol->flags, which I couldn't
ever see being uninitialized after leaving mpol_new().  So I'll guess
it's actually about accessing pol->w.cpuset_mems_allowed on line 354,
but still part of statement starting on line 353.

For w.cpuset_mems_allowed to be not initialized, and the nodes_equal()
reachable for a mempolicy where mpol_set_nodemask() is called in
do_mbind(), it seems the only possibility is a MPOL_PREFERRED policy
with empty set of nodes, i.e.  MPOL_LOCAL equivalent, with MPOL_F_LOCAL
flag.  Let's exclude such policies from the nodes_equal() check.  Note
the uninit access should be benign anyway, as rebinding this kind of
policy is always a no-op.  Therefore no actual need for stable
inclusion.

Link: http://lkml.kernel.org/r/a71997c3-e8ae-a787-d5ce-3db05768b27c@suse.cz
Link: http://lkml.kernel.org/r/73da3e9c-cc84-509e-17d9-0c434bb9967d@suse.cz
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reported-by: syzbot+b19c2dc2c990ea657a71@syzkaller.appspotmail.com
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Yisheng Xie <xieyisheng1@huawei.com>
Cc: zhong jiang <zhongjiang@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomemcg: killed threads should not invoke memcg OOM killer
Tetsuo Handa [Tue, 5 Mar 2019 23:46:47 +0000 (15:46 -0800)]
memcg: killed threads should not invoke memcg OOM killer

If a memory cgroup contains a single process with many threads
(including different process group sharing the mm) then it is possible
to trigger a race when the oom killer complains that there are no oom
elible tasks and complain into the log which is both annoying and
confusing because there is no actual problem.  The race looks as
follows:

P1 oom_reaper P2
try_charge try_charge
  mem_cgroup_out_of_memory
    mutex_lock(oom_lock)
      out_of_memory
        oom_kill_process(P1,P2)
         wake_oom_reaper
    mutex_unlock(oom_lock)
     oom_reap_task
  mutex_lock(oom_lock)
    select_bad_process # no victim

The problem is more visible with many threads.

Fix this by checking for fatal_signal_pending from
mem_cgroup_out_of_memory when the oom_lock is already held.

The oom bypass is safe because we do the same early in the try_charge
path already.  The situation migh have changed in the mean time.  It
should be safe to check for fatal_signal_pending and tsk_is_oom_victim
but for a better code readability abstract the current charge bypass
condition into should_force_charge and reuse it from that path.  "

Link: http://lkml.kernel.org/r/01370f70-e1f6-ebe4-b95e-0df21a0bc15e@i-love.sakura.ne.jp
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm/page_alloc.c: check return value of memblock_alloc_node_nopanic()
Mike Rapoport [Tue, 5 Mar 2019 23:46:43 +0000 (15:46 -0800)]
mm/page_alloc.c: check return value of memblock_alloc_node_nopanic()

There are two early memory allocations that use
memblock_alloc_node_nopanic() and do not check its return value.

While this happens very early during boot and chances that the
allocation will fail are diminishing, it is still worth to have proper
checks for the allocation errors.

Link: http://lkml.kernel.org/r/1547734941-944-1-git-send-email-rppt@linux.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Reviewed-by: William Kucharski <william.kucharski@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agoarch/powerpc/mm/hugetlb: NestMMU workaround for hugetlb mprotect RW upgrade
Aneesh Kumar K.V [Tue, 5 Mar 2019 23:46:40 +0000 (15:46 -0800)]
arch/powerpc/mm/hugetlb: NestMMU workaround for hugetlb mprotect RW upgrade

NestMMU requires us to mark the pte invalid and flush the tlb when we do
a RW upgrade of pte.  We fixed a variant of this in the fault path in
bd5050e38aec ("powerpc/mm/radix: Change pte relax sequence to handle
nest MMU hang").

Link: http://lkml.kernel.org/r/20190116085035.29729-6-aneesh.kumar@linux.ibm.com
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Reviewed-by: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm/hugetlb: add prot_modify_start/commit sequence for hugetlb update
Aneesh Kumar K.V [Tue, 5 Mar 2019 23:46:37 +0000 (15:46 -0800)]
mm/hugetlb: add prot_modify_start/commit sequence for hugetlb update

Architectures like ppc64 require to do a conditional tlb flush based on
the old and new value of pte.  Follow the regular pte change protection
sequence for hugetlb too.  This allows the architectures to override the
update sequence.

Link: http://lkml.kernel.org/r/20190116085035.29729-5-aneesh.kumar@linux.ibm.com
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Reviewed-by: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agoarch/powerpc/mm: Nest MMU workaround for mprotect RW upgrade
Aneesh Kumar K.V [Tue, 5 Mar 2019 23:46:33 +0000 (15:46 -0800)]
arch/powerpc/mm: Nest MMU workaround for mprotect RW upgrade

NestMMU requires us to mark the pte invalid and flush the tlb when we do
a RW upgrade of pte.  We fixed a variant of this in the fault path in
bd5050e38aec ("powerpc/mm/radix: Change pte relax sequence to handle
nest MMU hang").

Do the same for mprotect upgrades.

Hugetlb is handled in the next patch.

Link: http://lkml.kernel.org/r/20190116085035.29729-4-aneesh.kumar@linux.ibm.com
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm: update ptep_modify_prot_commit to take old pte value as arg
Aneesh Kumar K.V [Tue, 5 Mar 2019 23:46:29 +0000 (15:46 -0800)]
mm: update ptep_modify_prot_commit to take old pte value as arg

Architectures like ppc64 require to do a conditional tlb flush based on
the old and new value of pte.  Enable that by passing old pte value as
the arg.

Link: http://lkml.kernel.org/r/20190116085035.29729-3-aneesh.kumar@linux.ibm.com
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm: update ptep_modify_prot_start/commit to take vm_area_struct as arg
Aneesh Kumar K.V [Tue, 5 Mar 2019 23:46:26 +0000 (15:46 -0800)]
mm: update ptep_modify_prot_start/commit to take vm_area_struct as arg

Patch series "NestMMU pte upgrade workaround for mprotect", v5.

We can upgrade pte access (R -> RW transition) via mprotect.  We need to
make sure we follow the recommended pte update sequence as outlined in
commit bd5050e38aec ("powerpc/mm/radix: Change pte relax sequence to
handle nest MMU hang") for such updates.  This patch series does that.

This patch (of 5):

Some architectures may want to call flush_tlb_range from these helpers.

Link: http://lkml.kernel.org/r/20190116085035.29729-2-aneesh.kumar@linux.ibm.com
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm: fix some typos in mm directory
Wei Yang [Tue, 5 Mar 2019 23:46:22 +0000 (15:46 -0800)]
mm: fix some typos in mm directory

No functional change.

Link: http://lkml.kernel.org/r/20190118235123.27843-1-richard.weiyang@gmail.com
Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
Reviewed-by: Pekka Enberg <penberg@kernel.org>
Acked-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm/page_owner: move config option to mm/Kconfig.debug
Changbin Du [Tue, 5 Mar 2019 23:46:19 +0000 (15:46 -0800)]
mm/page_owner: move config option to mm/Kconfig.debug

Move the PAGE_OWNER option from submenu "Compile-time checks and
compiler options" to dedicated submenu "Memory Debugging".

Link: http://lkml.kernel.org/r/20190120024254.6270-1-changbin.du@gmail.com
Signed-off-by: Changbin Du <changbin.du@gmail.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm/mmap.c: remove some redundancy in arch_get_unmapped_area_topdown()
Yang Fan [Tue, 5 Mar 2019 23:46:16 +0000 (15:46 -0800)]
mm/mmap.c: remove some redundancy in arch_get_unmapped_area_topdown()

The variable 'addr' is redundant in arch_get_unmapped_area_topdown(),
just use parameter 'addr0' directly.  Then remove the const qualifier of
the parameter, and change its name to 'addr'.

And in according with other functions, remove the const qualifier of all
other no-pointer parameters in function arch_get_unmapped_area_topdown().

Link: http://lkml.kernel.org/r/20190127041112.25599-1-nullptr.cpp@gmail.com
Signed-off-by: Yang Fan <nullptr.cpp@gmail.com>
Reviewed-by: Mike Rapoport <rppt@linux.ibm.com>
Cc: William Kucharski <william.kucharski@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm, oom: remove 'prefer children over parent' heuristic
Shakeel Butt [Tue, 5 Mar 2019 23:46:12 +0000 (15:46 -0800)]
mm, oom: remove 'prefer children over parent' heuristic

Since the start of the git history of Linux, the kernel after selecting
the worst process to be oom-killed, prefer to kill its child (if the
child does not share mm with the parent).  Later it was changed to
prefer to kill a child who is worst.  If the parent is still the worst
then the parent will be killed.

This heuristic assumes that the children did less work than their parent
and by killing one of them, the work lost will be less.  However this is
very workload dependent.  If there is a workload which can benefit from
this heuristic, can use oom_score_adj to prefer children to be killed
before the parent.

The select_bad_process() has already selected the worst process in the
system/memcg.  There is no need to recheck the badness of its children
and hoping to find a worse candidate.  That's a lot of unneeded racy
work.  Also the heuristic is dangerous because it make fork bomb like
workloads to recover much later because we constantly pick and kill
processes which are not memory hogs.  So, let's remove this whole
heuristic.

[akpm@linux-foundation.org: coding-style fixes]
Link: http://lkml.kernel.org/r/20190121215850.221745-2-shakeelb@google.com
Signed-off-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Roman Gushchin <guro@fb.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm: no need to check return value of debugfs_create functions
Greg Kroah-Hartman [Tue, 5 Mar 2019 23:46:09 +0000 (15:46 -0800)]
mm: no need to check return value of debugfs_create functions

When calling debugfs functions, there is no need to ever check the
return value.  The function can work or not, but the code logic should
never do something different based on this.

Link: http://lkml.kernel.org/r/20190122152151.16139-14-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: David Rientjes <rientjes@google.com>
Cc: Laura Abbott <labbott@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm/memory.c: prevent mapping typed pages to userspace
Matthew Wilcox [Tue, 5 Mar 2019 23:46:06 +0000 (15:46 -0800)]
mm/memory.c: prevent mapping typed pages to userspace

Pages which use page_type must never be mapped to userspace as it would
destroy their page type.  Add an explicit check for this instead of
assuming that kernel drivers always get this right.

Link: http://lkml.kernel.org/r/20190129053830.3749-1-willy@infradead.org
Signed-off-by: Matthew Wilcox <willy@infradead.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm: prevent mapping slab pages to userspace
Matthew Wilcox [Tue, 5 Mar 2019 23:46:02 +0000 (15:46 -0800)]
mm: prevent mapping slab pages to userspace

It's never appropriate to map a page allocated by SLAB into userspace.
A buggy device driver might try this, or an attacker might be able to
find a way to make it happen.

Christoph said:

: Let's just fail the code.  Currently this may work with SLUB.  But SLAB
: and SLOB overlay fields with mapcount.  So you would have a corrupted page
: struct if you mapped a slab page to user space.

Link: http://lkml.kernel.org/r/20190125173827.2658-1-willy@infradead.org
Signed-off-by: Matthew Wilcox <willy@infradead.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Pekka Enberg <penberg@kernel.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm/vmalloc.c: fix kernel BUG at mm/vmalloc.c:512!
Uladzislau Rezki (Sony) [Tue, 5 Mar 2019 23:45:59 +0000 (15:45 -0800)]
mm/vmalloc.c: fix kernel BUG at mm/vmalloc.c:512!

One of the vmalloc stress test case triggers the kernel BUG():

  <snip>
  [60.562151] ------------[ cut here ]------------
  [60.562154] kernel BUG at mm/vmalloc.c:512!
  [60.562206] invalid opcode: 0000 [#1] PREEMPT SMP PTI
  [60.562247] CPU: 0 PID: 430 Comm: vmalloc_test/0 Not tainted 4.20.0+ #161
  [60.562293] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
  [60.562351] RIP: 0010:alloc_vmap_area+0x36f/0x390
  <snip>

it can happen due to big align request resulting in overflowing of
calculated address, i.e.  it becomes 0 after ALIGN()'s fixup.

Fix it by checking if calculated address is within vstart/vend range.

Link: http://lkml.kernel.org/r/20190124115648.9433-2-urezki@gmail.com
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Joel Fernandes <joelaf@google.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Oleksiy Avramchenko <oleksiy.avramchenko@sonymobile.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Garnier <thgarnie@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm, memcg: extract memcg maxable seq_file logic to seq_show_memcg_tunable
Chris Down [Tue, 5 Mar 2019 23:45:55 +0000 (15:45 -0800)]
mm, memcg: extract memcg maxable seq_file logic to seq_show_memcg_tunable

memcg has a significant number of files exposed to kernfs where their
value is either exposed directly or is "max" in the case of
PAGE_COUNTER_MAX.

This patch makes this generic by providing a single function to do this
work.  In combination with the previous patch adding
mem_cgroup_from_seq, this makes all of the seq_show feeder functions
significantly more simple.

Link: http://lkml.kernel.org/r/20190124194100.GA31425@chrisdown.name
Signed-off-by: Chris Down <chris@chrisdown.name>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Roman Gushchin <guro@fb.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm, memcg: create mem_cgroup_from_seq
Chris Down [Tue, 5 Mar 2019 23:45:52 +0000 (15:45 -0800)]
mm, memcg: create mem_cgroup_from_seq

This is the start of a series of patches similar to my earlier
DEFINE_MEMCG_MAX_OR_VAL work, but with less Macro Magic(tm).

There are a bunch of places we go from seq_file to mem_cgroup, which
currently requires manually getting the css, then getting the mem_cgroup
from the css.  It's in enough places now that having mem_cgroup_from_seq
makes sense (and also makes the next patch a bit nicer).

Link: http://lkml.kernel.org/r/20190124194050.GA31341@chrisdown.name
Signed-off-by: Chris Down <chris@chrisdown.name>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Roman Gushchin <guro@fb.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agokernel: cgroup: add poll file operation
Johannes Weiner [Tue, 5 Mar 2019 23:45:48 +0000 (15:45 -0800)]
kernel: cgroup: add poll file operation

Cgroup has a standardized poll/notification mechanism for waking all
pollers on all fds when a filesystem node changes.  To allow polling for
custom events, add a .poll callback that can override the default.

This is in preparation for pollable cgroup pressure files which have
per-fd trigger configurations.

Link: http://lkml.kernel.org/r/20190124211518.244221-3-surenb@google.com
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Cc: Dennis Zhou <dennis@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Li Zefan <lizefan@huawei.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agofs: kernfs: add poll file operation
Johannes Weiner [Tue, 5 Mar 2019 23:45:45 +0000 (15:45 -0800)]
fs: kernfs: add poll file operation

Patch series "psi: pressure stall monitors", v3.

Android is adopting psi to detect and remedy memory pressure that
results in stuttering and decreased responsiveness on mobile devices.

Psi gives us the stall information, but because we're dealing with
latencies in the millisecond range, periodically reading the pressure
files to detect stalls in a timely fashion is not feasible.  Psi also
doesn't aggregate its averages at a high enough frequency right now.

This patch series extends the psi interface such that users can
configure sensitive latency thresholds and use poll() and friends to be
notified when these are breached.

As high-frequency aggregation is costly, it implements an aggregation
method that is optimized for fast, short-interval averaging, and makes
the aggregation frequency adaptive, such that high-frequency updates
only happen while monitored stall events are actively occurring.

With these patches applied, Android can monitor for, and ward off,
mounting memory shortages before they cause problems for the user.  For
example, using memory stall monitors in userspace low memory killer
daemon (lmkd) we can detect mounting pressure and kill less important
processes before device becomes visibly sluggish.

In our memory stress testing psi memory monitors produce roughly 10x
less false positives compared to vmpressure signals.  Having ability to
specify multiple triggers for the same psi metric allows other parts of
Android framework to monitor memory state of the device and act
accordingly.

The new interface is straightforward.  The user opens one of the
pressure files for writing and writes a trigger description into the
file descriptor that defines the stall state - some or full, and the
maximum stall time over a given window of time.  E.g.:

        /* Signal when stall time exceeds 100ms of a 1s window */
        char trigger[] = "full 100000 1000000";
        fd = open("/proc/pressure/memory");
        write(fd, trigger, sizeof(trigger));
        while (poll() >= 0) {
                ...
        }
        close(fd);

When the monitored stall state is entered, psi adapts its aggregation
frequency according to what the configured time window requires in order
to emit event signals in a timely fashion.  Once the stalling subsides,
aggregation reverts back to normal.

The trigger is associated with the open file descriptor.  To stop
monitoring, the user only needs to close the file descriptor and the
trigger is discarded.

Patches 1-4 prepare the psi code for polling support.  Patch 5
implements the adaptive polling logic, the pressure growth detection
optimized for short intervals, and hooks up write() and poll() on the
pressure files.

The patches were developed in collaboration with Johannes Weiner.

This patch (of 5):

Kernfs has a standardized poll/notification mechanism for waking all
pollers on all fds when a filesystem node changes.  To allow polling for
custom events, add a .poll callback that can override the default.

This is in preparation for pollable cgroup pressure files which have
per-fd trigger configurations.

Link: http://lkml.kernel.org/r/20190124211518.244221-2-surenb@google.com
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Cc: Dennis Zhou <dennis@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Li Zefan <lizefan@huawei.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm, compaction: capture a page under direct compaction
Mel Gorman [Tue, 5 Mar 2019 23:45:41 +0000 (15:45 -0800)]
mm, compaction: capture a page under direct compaction

Compaction is inherently race-prone as a suitable page freed during
compaction can be allocated by any parallel task.  This patch uses a
capture_control structure to isolate a page immediately when it is freed
by a direct compactor in the slow path of the page allocator.  The
intent is to avoid redundant scanning.

                                     5.0.0-rc1              5.0.0-rc1
                               selective-v3r17          capture-v3r19
Amean     fault-both-1         0.00 (   0.00%)        0.00 *   0.00%*
Amean     fault-both-3      2582.11 (   0.00%)     2563.68 (   0.71%)
Amean     fault-both-5      4500.26 (   0.00%)     4233.52 (   5.93%)
Amean     fault-both-7      5819.53 (   0.00%)     6333.65 (  -8.83%)
Amean     fault-both-12     9321.18 (   0.00%)     9759.38 (  -4.70%)
Amean     fault-both-18     9782.76 (   0.00%)    10338.76 (  -5.68%)
Amean     fault-both-24    15272.81 (   0.00%)    13379.55 *  12.40%*
Amean     fault-both-30    15121.34 (   0.00%)    16158.25 (  -6.86%)
Amean     fault-both-32    18466.67 (   0.00%)    18971.21 (  -2.73%)

Latency is only moderately affected but the devil is in the details.  A
closer examination indicates that base page fault latency is reduced but
latency of huge pages is increased as it takes creater care to succeed.
Part of the "problem" is that allocation success rates are close to 100%
even when under pressure and compaction gets harder

                                5.0.0-rc1              5.0.0-rc1
                          selective-v3r17          capture-v3r19
Percentage huge-3        96.70 (   0.00%)       98.23 (   1.58%)
Percentage huge-5        96.99 (   0.00%)       95.30 (  -1.75%)
Percentage huge-7        94.19 (   0.00%)       97.24 (   3.24%)
Percentage huge-12       94.95 (   0.00%)       97.35 (   2.53%)
Percentage huge-18       96.74 (   0.00%)       97.30 (   0.58%)
Percentage huge-24       97.07 (   0.00%)       97.55 (   0.50%)
Percentage huge-30       95.69 (   0.00%)       98.50 (   2.95%)
Percentage huge-32       96.70 (   0.00%)       99.27 (   2.65%)

And scan rates are reduced as expected by 6% for the migration scanner
and 29% for the free scanner indicating that there is less redundant
work.

Compaction migrate scanned    20815362    19573286
Compaction free scanned       16352612    11510663

[mgorman@techsingularity.net: remove redundant check]
Link: http://lkml.kernel.org/r/20190201143853.GH9565@techsingularity.net
Link: http://lkml.kernel.org/r/20190118175136.31341-23-mgorman@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: David Rientjes <rientjes@google.com>
Cc: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm, compaction: be selective about what pageblocks to clear skip hints
Mel Gorman [Tue, 5 Mar 2019 23:45:38 +0000 (15:45 -0800)]
mm, compaction: be selective about what pageblocks to clear skip hints

Pageblock hints are cleared when compaction restarts or kswapd makes
enough progress that it can sleep but it's over-eager in that the bit is
cleared for migration sources with no LRU pages and migration targets
with no free pages.  As pageblock skip hint flushes are relatively rare
and out-of-band with respect to kswapd, this patch makes a few more
expensive checks to see if it's appropriate to even clear the bit.
Every pageblock that is not cleared will avoid 512 pages being scanned
unnecessarily on x86-64.

The impact is variable with different workloads showing small
differences in latency, success rates and scan rates.  This is expected
as clearing the hints is not that common but doing a small amount of
work out-of-band to avoid a large amount of work in-band later is
generally a good thing.

Link: http://lkml.kernel.org/r/20190118175136.31341-22-mgorman@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Qian Cai <cai@lca.pw>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: David Rientjes <rientjes@google.com>
Cc: YueHaibing <yuehaibing@huawei.com>
[cai@lca.pw: no stuck in __reset_isolation_pfn()]
Link: http://lkml.kernel.org/r/20190206034732.75687-1-cai@lca.pw
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm, compaction: sample pageblocks for free pages
Mel Gorman [Tue, 5 Mar 2019 23:45:34 +0000 (15:45 -0800)]
mm, compaction: sample pageblocks for free pages

Once fast searching finishes, there is a possibility that the linear
scanner is scanning full blocks found by the fast scanner earlier.  This
patch uses an adaptive stride to sample pageblocks for free pages.  The
more consecutive full pageblocks encountered, the larger the stride
until a pageblock with free pages is found.  The scanners might meet
slightly sooner but it is an acceptable risk given that the search of
the free lists may still encounter the pages and adjust the cached PFN
of the free scanner accordingly.

                                     5.0.0-rc1              5.0.0-rc1
                              roundrobin-v3r17       samplefree-v3r17
Amean     fault-both-1         0.00 (   0.00%)        0.00 *   0.00%*
Amean     fault-both-3      2752.37 (   0.00%)     2729.95 (   0.81%)
Amean     fault-both-5      4341.69 (   0.00%)     4397.80 (  -1.29%)
Amean     fault-both-7      6308.75 (   0.00%)     6097.61 (   3.35%)
Amean     fault-both-12    10241.81 (   0.00%)     9407.15 (   8.15%)
Amean     fault-both-18    13736.09 (   0.00%)    10857.63 *  20.96%*
Amean     fault-both-24    16853.95 (   0.00%)    13323.24 *  20.95%*
Amean     fault-both-30    15862.61 (   0.00%)    17345.44 (  -9.35%)
Amean     fault-both-32    18450.85 (   0.00%)    16892.00 (   8.45%)

The latency is mildly improved offseting some overhead from earlier
patches that are prerequisites for the rest of the series.  However, a
major impact is on the free scan rate with an 82% reduction.

                                5.0.0-rc1      5.0.0-rc1
                         roundrobin-v3r17 samplefree-v3r17
Compaction migrate scanned    21607271            20116887
Compaction free scanned       95336406            16668703

It's also the first time in the series where the number of pages scanned
by the migration scanner is greater than the free scanner due to the
increased search efficiency.

Link: http://lkml.kernel.org/r/20190118175136.31341-21-mgorman@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: David Rientjes <rientjes@google.com>
Cc: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm, compaction: round-robin the order while searching the free lists for a target
Mel Gorman [Tue, 5 Mar 2019 23:45:31 +0000 (15:45 -0800)]
mm, compaction: round-robin the order while searching the free lists for a target

As compaction proceeds and creates high-order blocks, the free list
search gets less efficient as the larger blocks are used as compaction
targets.  Eventually, the larger blocks will be behind the migration
scanner for partially migrated pageblocks and the search fails.  This
patch round-robins what orders are searched so that larger blocks can be
ignored and find smaller blocks that can be used as migration targets.

The overall impact was small on 1-socket but it avoids corner cases
where the migration/free scanners meet prematurely or situations where
many of the pageblocks encountered by the free scanner are almost full
instead of being properly packed.  Previous testing had indicated that
without this patch there were occasional large spikes in the free
scanner without this patch.

[dan.carpenter@oracle.com: fix static checker warning]
Link: http://lkml.kernel.org/r/20190118175136.31341-20-mgorman@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm, compaction: reduce premature advancement of the migration target scanner
Mel Gorman [Tue, 5 Mar 2019 23:45:28 +0000 (15:45 -0800)]
mm, compaction: reduce premature advancement of the migration target scanner

The fast isolation of free pages allows the cached PFN of the free
scanner to advance faster than necessary depending on the contents of
the free list.  The key is that fast_isolate_freepages() can update
zone->compact_cached_free_pfn via isolate_freepages_block().  When the
fast search fails, the linear scan can start from a point that has
skipped valid migration targets, particularly pageblocks with just
low-order free pages.  This can cause the migration source/target
scanners to meet prematurely causing a reset.

This patch starts by avoiding an update of the pageblock skip
information and cached PFN from isolate_freepages_block() and puts the
responsibility of updating that information in the callers.  The fast
scanner will update the cached PFN if and only if it finds a block that
is higher than the existing cached PFN and sets the skip if the
pageblock is full or nearly full.  The linear scanner will update
skipped information and the cached PFN only when a block is completely
scanned.  The total impact is that the free scanner advances more slowly
as it is primarily driven by the linear scanner instead of the fast
search.

                                     5.0.0-rc1              5.0.0-rc1
                               noresched-v3r17         slowfree-v3r17
Amean     fault-both-3      2965.68 (   0.00%)     3036.75 (  -2.40%)
Amean     fault-both-5      3995.90 (   0.00%)     4522.24 * -13.17%*
Amean     fault-both-7      5842.12 (   0.00%)     6365.35 (  -8.96%)
Amean     fault-both-12     9550.87 (   0.00%)    10340.93 (  -8.27%)
Amean     fault-both-18    13304.72 (   0.00%)    14732.46 ( -10.73%)
Amean     fault-both-24    14618.59 (   0.00%)    16288.96 ( -11.43%)
Amean     fault-both-30    16650.96 (   0.00%)    16346.21 (   1.83%)
Amean     fault-both-32    17145.15 (   0.00%)    19317.49 ( -12.67%)

The impact to latency is higher than the last version but it appears to
be due to a slight increase in the free scan rates which is a potential
side-effect of the patch.  However, this is necessary for later patches
that are more careful about how pageblocks are treated as earlier
iterations of those patches hit corner cases where the restarts were
punishing and very visible.

Link: http://lkml.kernel.org/r/20190118175136.31341-19-mgorman@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: David Rientjes <rientjes@google.com>
Cc: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm, compaction: do not consider a need to reschedule as contention
Mel Gorman [Tue, 5 Mar 2019 23:45:24 +0000 (15:45 -0800)]
mm, compaction: do not consider a need to reschedule as contention

Scanning on large machines can take a considerable length of time and
eventually need to be rescheduled.  This is treated as an abort event
but that's not appropriate as the attempt is likely to be retried after
making numerous checks and taking another cycle through the page
allocator.  This patch will check the need to reschedule if necessary
but continue the scanning.

The main benefit is reduced scanning when compaction is taking a long
time or the machine is over-saturated.  It also avoids an unnecessary
exit of compaction that ends up being retried by the page allocator in
the outer loop.

                                     5.0.0-rc1              5.0.0-rc1
                              synccached-v3r16        noresched-v3r17
Amean     fault-both-1         0.00 (   0.00%)        0.00 *   0.00%*
Amean     fault-both-3      2958.27 (   0.00%)     2965.68 (  -0.25%)
Amean     fault-both-5      4091.90 (   0.00%)     3995.90 (   2.35%)
Amean     fault-both-7      5803.05 (   0.00%)     5842.12 (  -0.67%)
Amean     fault-both-12     9481.06 (   0.00%)     9550.87 (  -0.74%)
Amean     fault-both-18    14141.51 (   0.00%)    13304.72 (   5.92%)
Amean     fault-both-24    16438.00 (   0.00%)    14618.59 (  11.07%)
Amean     fault-both-30    17531.72 (   0.00%)    16650.96 (   5.02%)
Amean     fault-both-32    17101.96 (   0.00%)    17145.15 (  -0.25%)

Link: http://lkml.kernel.org/r/20190118175136.31341-18-mgorman@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: David Rientjes <rientjes@google.com>
Cc: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm, compaction: rework compact_should_abort as compact_check_resched
Mel Gorman [Tue, 5 Mar 2019 23:45:21 +0000 (15:45 -0800)]
mm, compaction: rework compact_should_abort as compact_check_resched

With incremental changes, compact_should_abort no longer makes any
documented sense.  Rename to compact_check_resched and update the
associated comments.  There is no benefit other than reducing redundant
code and making the intent slightly clearer.  It could potentially be
merged with earlier patches but it just makes the review slightly
harder.

Link: http://lkml.kernel.org/r/20190118175136.31341-17-mgorman@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: David Rientjes <rientjes@google.com>
Cc: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm, compaction: keep cached migration PFNs synced for unusable pageblocks
Mel Gorman [Tue, 5 Mar 2019 23:45:18 +0000 (15:45 -0800)]
mm, compaction: keep cached migration PFNs synced for unusable pageblocks

Migrate has separate cached PFNs for ASYNC and SYNC* migration on the
basis that some migrations will fail in ASYNC mode.  However, if the
cached PFNs match at the start of scanning and pageblocks are skipped
due to having no isolation candidates, then the sync state does not
matter.  This patch keeps matching cached PFNs in sync until a pageblock
with isolation candidates is found.

The actual benefit is marginal given that the sync scanner following the
async scanner will often skip a number of pageblocks but it's useless
work.  Any benefit depends heavily on whether the scanners restarted
recently.

Link: http://lkml.kernel.org/r/20190118175136.31341-16-mgorman@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: David Rientjes <rientjes@google.com>
Cc: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm, compaction: check early for huge pages encountered by the migration scanner
Mel Gorman [Tue, 5 Mar 2019 23:45:14 +0000 (15:45 -0800)]
mm, compaction: check early for huge pages encountered by the migration scanner

When scanning for sources or targets, PageCompound is checked for huge
pages as they can be skipped quickly but it happens relatively late
after a lot of setup and checking.  This patch short-cuts the check to
make it earlier.  It might still change when the lock is acquired but
this has less overhead overall.  The free scanner advances but the
migration scanner does not.  Typically the free scanner encounters more
movable blocks that change state over the lifetime of the system and
also tends to scan more aggressively as it's actively filling its
portion of the physical address space with data.  This could change in
the future but for the moment, this worked better in practice and
incurred fewer scan restarts.

The impact on latency and allocation success rates is marginal but the
free scan rates are reduced by 15% and system CPU usage is reduced by
3.3%.  The 2-socket results are not materially different.

Link: http://lkml.kernel.org/r/20190118175136.31341-15-mgorman@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: David Rientjes <rientjes@google.com>
Cc: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm, compaction: finish pageblock scanning on contention
Mel Gorman [Tue, 5 Mar 2019 23:45:11 +0000 (15:45 -0800)]
mm, compaction: finish pageblock scanning on contention

Async migration aborts on spinlock contention but contention can be high
when there are multiple compaction attempts and kswapd is active.  The
consequence is that the migration scanners move forward uselessly while
still contending on locks for longer while leaving suitable migration
sources behind.

This patch will acquire the lock but track when contention occurs.  When
it does, the current pageblock will finish as compaction may succeed for
that block and then abort.  This will have a variable impact on latency
as in some cases useless scanning is avoided (reduces latency) but a
lock will be contended (increase latency) or a single contended
pageblock is scanned that would otherwise have been skipped (increase
latency).

                                     5.0.0-rc1              5.0.0-rc1
                                norescan-v3r16    finishcontend-v3r16
Amean     fault-both-1         0.00 (   0.00%)        0.00 *   0.00%*
Amean     fault-both-3      3002.07 (   0.00%)     3153.17 (  -5.03%)
Amean     fault-both-5      4684.47 (   0.00%)     4280.52 (   8.62%)
Amean     fault-both-7      6815.54 (   0.00%)     5811.50 *  14.73%*
Amean     fault-both-12    10864.02 (   0.00%)     9276.85 (  14.61%)
Amean     fault-both-18    12247.52 (   0.00%)    11032.67 (   9.92%)
Amean     fault-both-24    15683.99 (   0.00%)    14285.70 (   8.92%)
Amean     fault-both-30    18620.02 (   0.00%)    16293.76 *  12.49%*
Amean     fault-both-32    19250.28 (   0.00%)    16721.02 *  13.14%*

                                5.0.0-rc1              5.0.0-rc1
                           norescan-v3r16    finishcontend-v3r16
Percentage huge-1         0.00 (   0.00%)        0.00 (   0.00%)
Percentage huge-3        95.00 (   0.00%)       96.82 (   1.92%)
Percentage huge-5        94.22 (   0.00%)       95.40 (   1.26%)
Percentage huge-7        92.35 (   0.00%)       95.92 (   3.86%)
Percentage huge-12       91.90 (   0.00%)       96.73 (   5.25%)
Percentage huge-18       89.58 (   0.00%)       96.77 (   8.03%)
Percentage huge-24       90.03 (   0.00%)       96.05 (   6.69%)
Percentage huge-30       89.14 (   0.00%)       96.81 (   8.60%)
Percentage huge-32       90.58 (   0.00%)       97.41 (   7.54%)

There is a variable impact that is mostly good on latency while allocation
success rates are slightly higher.  System CPU usage is reduced by about
10% but scan rate impact is mixed

Compaction migrate scanned    27997659.00    20148867
Compaction free scanned      120782791.00   118324914

Migration scan rates are reduced 28% which is expected as a pageblock is
used by the async scanner instead of skipped.  The impact on the free
scanner is known to be variable.  Overall the primary justification for
this patch is that completing scanning of a pageblock is very important
for later patches.

[yuehaibing@huawei.com: fix unused variable warning]
Link: http://lkml.kernel.org/r/20190118175136.31341-14-mgorman@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: YueHaibing <yuehaibing@huawei.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm, compaction: avoid rescanning the same pageblock multiple times
Mel Gorman [Tue, 5 Mar 2019 23:45:07 +0000 (15:45 -0800)]
mm, compaction: avoid rescanning the same pageblock multiple times

Pageblocks are marked for skip when no pages are isolated after a scan.
However, it's possible to hit corner cases where the migration scanner
gets stuck near the boundary between the source and target scanner.  Due
to pages being migrated in blocks of COMPACT_CLUSTER_MAX, pages that are
migrated can be reallocated before the pageblock is complete.  The
pageblock is not necessarily skipped so it can be rescanned multiple
times.  Similarly, a pageblock with some dirty/writeback pages may fail
to migrate and be rescanned until writeback completes which is wasteful.

This patch tracks if a pageblock is being rescanned.  If so, then the
entire pageblock will be migrated as one operation.  This narrows the
race window during which pages can be reallocated during migration.
Secondly, if there are pages that cannot be isolated then the pageblock
will still be fully scanned and marked for skipping.  On the second
rescan, the pageblock skip is set and the migration scanner makes
progress.

                                     5.0.0-rc1              5.0.0-rc1
                                findfree-v3r16         norescan-v3r16
Amean     fault-both-1         0.00 (   0.00%)        0.00 *   0.00%*
Amean     fault-both-3      3200.68 (   0.00%)     3002.07 (   6.21%)
Amean     fault-both-5      4847.75 (   0.00%)     4684.47 (   3.37%)
Amean     fault-both-7      6658.92 (   0.00%)     6815.54 (  -2.35%)
Amean     fault-both-12    11077.62 (   0.00%)    10864.02 (   1.93%)
Amean     fault-both-18    12403.97 (   0.00%)    12247.52 (   1.26%)
Amean     fault-both-24    15607.10 (   0.00%)    15683.99 (  -0.49%)
Amean     fault-both-30    18752.27 (   0.00%)    18620.02 (   0.71%)
Amean     fault-both-32    21207.54 (   0.00%)    19250.28 *   9.23%*

                                5.0.0-rc1              5.0.0-rc1
                           findfree-v3r16         norescan-v3r16
Percentage huge-3        96.86 (   0.00%)       95.00 (  -1.91%)
Percentage huge-5        93.72 (   0.00%)       94.22 (   0.53%)
Percentage huge-7        94.31 (   0.00%)       92.35 (  -2.08%)
Percentage huge-12       92.66 (   0.00%)       91.90 (  -0.82%)
Percentage huge-18       91.51 (   0.00%)       89.58 (  -2.11%)
Percentage huge-24       90.50 (   0.00%)       90.03 (  -0.52%)
Percentage huge-30       91.57 (   0.00%)       89.14 (  -2.65%)
Percentage huge-32       91.00 (   0.00%)       90.58 (  -0.46%)

Negligible difference but this was likely a case when the specific
corner case was not hit.  A previous run of the same patch based on an
earlier iteration of the series showed large differences where migration
rates could be halved when the corner case was hit.

The specific corner case where migration scan rates go through the roof
was due to a dirty/writeback pageblock located at the boundary of the
migration/free scanner did not happen in this case.  When it does
happen, the scan rates multipled by massive margins.

Link: http://lkml.kernel.org/r/20190118175136.31341-13-mgorman@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: David Rientjes <rientjes@google.com>
Cc: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm, compaction: use free lists to quickly locate a migration target
Mel Gorman [Tue, 5 Mar 2019 23:45:01 +0000 (15:45 -0800)]
mm, compaction: use free lists to quickly locate a migration target

Similar to the migration scanner, this patch uses the free lists to
quickly locate a migration target.  The search is different in that
lower orders will be searched for a suitable high PFN if necessary but
the search is still bound.  This is justified on the grounds that the
free scanner typically scans linearly much more than the migration
scanner.

If a free page is found, it is isolated and compaction continues if
enough pages were isolated.  For SYNC* scanning, the full pageblock is
scanned for any remaining free pages so that is can be marked for
skipping in the near future.

1-socket thpfioscale
                                     5.0.0-rc1              5.0.0-rc1
                                 isolmig-v3r15         findfree-v3r16
Amean     fault-both-3      3024.41 (   0.00%)     3200.68 (  -5.83%)
Amean     fault-both-5      4749.30 (   0.00%)     4847.75 (  -2.07%)
Amean     fault-both-7      6454.95 (   0.00%)     6658.92 (  -3.16%)
Amean     fault-both-12    10324.83 (   0.00%)    11077.62 (  -7.29%)
Amean     fault-both-18    12896.82 (   0.00%)    12403.97 (   3.82%)
Amean     fault-both-24    13470.60 (   0.00%)    15607.10 * -15.86%*
Amean     fault-both-30    17143.99 (   0.00%)    18752.27 (  -9.38%)
Amean     fault-both-32    17743.91 (   0.00%)    21207.54 * -19.52%*

The impact on latency is variable but the search is optimistic and
sensitive to the exact system state.  Success rates are similar but the
major impact is to the rate of scanning

                                5.0.0-rc1      5.0.0-rc1
                            isolmig-v3r15 findfree-v3r16
Compaction migrate scanned    25646769          29507205
Compaction free scanned      201558184         100359571

The free scan rates are reduced by 50%.  The 2-socket reductions for the
free scanner are more dramatic which is a likely reflection that the
machine has more memory.

[dan.carpenter@oracle.com: fix static checker warning]
[vbabka@suse.cz: correct number of pages scanned for lower orders]
Link: http://lkml.kernel.org/r/20190118175136.31341-12-mgorman@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm, compaction: keep migration source private to a single compaction instance
Mel Gorman [Tue, 5 Mar 2019 23:44:58 +0000 (15:44 -0800)]
mm, compaction: keep migration source private to a single compaction instance

Due to either a fast search of the free list or a linear scan, it is
possible for multiple compaction instances to pick the same pageblock
for migration.  This is lucky for one scanner and increased scanning for
all the others.  It also allows a race between requests on which first
allocates the resulting free block.

This patch tests and updates the pageblock skip for the migration
scanner carefully.  When isolating a block, it will check and skip if
the block is already in use.  Once the zone lock is acquired, it will be
rechecked so that only one scanner can set the pageblock skip for
exclusive use.  Any scanner contending will continue with a linear scan.
The skip bit is still set if no pages can be isolated in a range.  While
this may result in redundant scanning, it avoids unnecessarily acquiring
the zone lock when there are no suitable migration sources.

1-socket thpscale
Amean     fault-both-1         0.00 (   0.00%)        0.00 *   0.00%*
Amean     fault-both-3      3390.40 (   0.00%)     3024.41 (  10.80%)
Amean     fault-both-5      5082.28 (   0.00%)     4749.30 (   6.55%)
Amean     fault-both-7      7012.51 (   0.00%)     6454.95 (   7.95%)
Amean     fault-both-12    11346.63 (   0.00%)    10324.83 (   9.01%)
Amean     fault-both-18    15324.19 (   0.00%)    12896.82 *  15.84%*
Amean     fault-both-24    16088.50 (   0.00%)    13470.60 *  16.27%*
Amean     fault-both-30    18723.42 (   0.00%)    17143.99 (   8.44%)
Amean     fault-both-32    18612.01 (   0.00%)    17743.91 (   4.66%)

                                5.0.0-rc1              5.0.0-rc1
                            findmig-v3r15          isolmig-v3r15
Percentage huge-3        89.83 (   0.00%)       92.96 (   3.48%)
Percentage huge-5        91.96 (   0.00%)       93.26 (   1.41%)
Percentage huge-7        92.85 (   0.00%)       93.63 (   0.84%)
Percentage huge-12       92.74 (   0.00%)       92.80 (   0.07%)
Percentage huge-18       91.71 (   0.00%)       91.62 (  -0.10%)
Percentage huge-24       92.13 (   0.00%)       91.50 (  -0.69%)
Percentage huge-30       93.79 (   0.00%)       92.73 (  -1.13%)
Percentage huge-32       91.27 (   0.00%)       91.94 (   0.74%)

This shows a reasonable reduction in latency as multiple compaction
scanners do not operate on the same blocks with a similar allocation
success rate.

Compaction migrate scanned    41093126    25646769

Migration scan rates are reduced by 38%.

Link: http://lkml.kernel.org/r/20190118175136.31341-11-mgorman@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: David Rientjes <rientjes@google.com>
Cc: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm, compaction: use free lists to quickly locate a migration source
Mel Gorman [Tue, 5 Mar 2019 23:44:54 +0000 (15:44 -0800)]
mm, compaction: use free lists to quickly locate a migration source

The migration scanner is a linear scan of a zone with a potentiall large
search space.  Furthermore, many pageblocks are unusable such as those
filled with reserved pages or partially filled with pages that cannot
migrate.  These still get scanned in the common case of allocating a THP
and the cost accumulates.

The patch uses a partial search of the free lists to locate a migration
source candidate that is marked as MOVABLE when allocating a THP.  It
prefers picking a block with a larger number of free pages already on
the basis that there are fewer pages to migrate to free the entire
block.  The lowest PFN found during searches is tracked as the basis of
the start for the linear search after the first search of the free list
fails.  After the search, the free list is shuffled so that the next
search will not encounter the same page.  If the search fails then the
subsequent searches will be shorter and the linear scanner is used.

If this search fails, or if the request is for a small or
unmovable/reclaimable allocation then the linear scanner is still used.
It is somewhat pointless to use the list search in those cases.  Small
free pages must be used for the search and there is no guarantee that
movable pages are located within that block that are contiguous.

                                     5.0.0-rc1              5.0.0-rc1
                                 noboost-v3r10          findmig-v3r15
Amean     fault-both-3      3771.41 (   0.00%)     3390.40 (  10.10%)
Amean     fault-both-5      5409.05 (   0.00%)     5082.28 (   6.04%)
Amean     fault-both-7      7040.74 (   0.00%)     7012.51 (   0.40%)
Amean     fault-both-12    11887.35 (   0.00%)    11346.63 (   4.55%)
Amean     fault-both-18    16718.19 (   0.00%)    15324.19 (   8.34%)
Amean     fault-both-24    21157.19 (   0.00%)    16088.50 *  23.96%*
Amean     fault-both-30    21175.92 (   0.00%)    18723.42 *  11.58%*
Amean     fault-both-32    21339.03 (   0.00%)    18612.01 *  12.78%*

                                5.0.0-rc1              5.0.0-rc1
                            noboost-v3r10          findmig-v3r15
Percentage huge-3        86.50 (   0.00%)       89.83 (   3.85%)
Percentage huge-5        92.52 (   0.00%)       91.96 (  -0.61%)
Percentage huge-7        92.44 (   0.00%)       92.85 (   0.44%)
Percentage huge-12       92.98 (   0.00%)       92.74 (  -0.25%)
Percentage huge-18       91.70 (   0.00%)       91.71 (   0.02%)
Percentage huge-24       91.59 (   0.00%)       92.13 (   0.60%)
Percentage huge-30       90.14 (   0.00%)       93.79 (   4.04%)
Percentage huge-32       90.03 (   0.00%)       91.27 (   1.37%)

This shows an improvement in allocation latencies with similar
allocation success rates.  While not presented, there was a 31%
reduction in migration scanning and a 8% reduction on system CPU usage.
A 2-socket machine showed similar benefits.

[mgorman@techsingularity.net: several fixes]
Link: http://lkml.kernel.org/r/20190204120111.GL9565@techsingularity.net
[vbabka@suse.cz: migrate block that was found-fast, some optimisations]
Link: http://lkml.kernel.org/r/20190118175136.31341-10-mgorman@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <Vbabka@suse.cz>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: David Rientjes <rientjes@google.com>
Cc: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm, compaction: ignore the fragmentation avoidance boost for isolation and compaction
Mel Gorman [Tue, 5 Mar 2019 23:44:50 +0000 (15:44 -0800)]
mm, compaction: ignore the fragmentation avoidance boost for isolation and compaction

When pageblocks get fragmented, watermarks are artifically boosted to
reclaim pages to avoid further fragmentation events.  However,
compaction is often either fragmentation-neutral or moving movable pages
away from unmovable/reclaimable pages.  As the true watermarks are
preserved, allow compaction to ignore the boost factor.

The expected impact is very slight as the main benefit is that
compaction is slightly more likely to succeed when the system has been
fragmented very recently.  On both 1-socket and 2-socket machines for
THP-intensive allocation during fragmentation the success rate was
increased by less than 1% which is marginal.  However, detailed tracing
indicated that failure of migration due to a premature ENOMEM triggered
by watermark checks were eliminated.

Link: http://lkml.kernel.org/r/20190118175136.31341-9-mgorman@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: David Rientjes <rientjes@google.com>
Cc: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm, compaction: always finish scanning of a full pageblock
Mel Gorman [Tue, 5 Mar 2019 23:44:46 +0000 (15:44 -0800)]
mm, compaction: always finish scanning of a full pageblock

When compaction is finishing, it uses a flag to ensure the pageblock is
complete but it makes sense to always complete migration of a pageblock.
Minimally, skip information is based on a pageblock and partially
scanned pageblocks may incur more scanning in the future.  The pageblock
skip handling also becomes more strict later in the series and the hint
is more useful if a complete pageblock was always scanned.

The potentially impacts latency as more scanning is done but it's not a
consistent win or loss as the scanning is not always a high percentage
of the pageblock and sometimes it is offset by future reductions in
scanning.  Hence, the results are not presented this time due to a
misleading mix of gains/losses without any clear pattern.  However, full
scanning of the pageblock is important for later patches.

Link: http://lkml.kernel.org/r/20190118175136.31341-8-mgorman@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: David Rientjes <rientjes@google.com>
Cc: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm, migrate: immediately fail migration of a page with no migration handler
Mel Gorman [Tue, 5 Mar 2019 23:44:43 +0000 (15:44 -0800)]
mm, migrate: immediately fail migration of a page with no migration handler

Pages with no migration handler use a fallback handler which sometimes
works and sometimes persistently retries.  A historical example was
blockdev pages but there are others such as odd refcounting when
page->private is used.  These are retried multiple times which is
wasteful during compaction so this patch will fail migration faster
unless the caller specifies MIGRATE_SYNC.

This is not expected to help THP allocation success rates but it did
reduce latencies very slightly in some cases.

1-socket thpfioscale
                                        4.20.0                 4.20.0
                              noreserved-v2r15         failfast-v2r15
Amean     fault-both-1         0.00 (   0.00%)        0.00 *   0.00%*
Amean     fault-both-3      3839.67 (   0.00%)     3833.72 (   0.15%)
Amean     fault-both-5      5177.47 (   0.00%)     4967.15 (   4.06%)
Amean     fault-both-7      7245.03 (   0.00%)     7139.19 (   1.46%)
Amean     fault-both-12    11534.89 (   0.00%)    11326.30 (   1.81%)
Amean     fault-both-18    16241.10 (   0.00%)    16270.70 (  -0.18%)
Amean     fault-both-24    19075.91 (   0.00%)    19839.65 (  -4.00%)
Amean     fault-both-30    22712.11 (   0.00%)    21707.05 (   4.43%)
Amean     fault-both-32    21692.92 (   0.00%)    21968.16 (  -1.27%)

The 2-socket results are not materially different.  Scan rates are
similar as expected.

Link: http://lkml.kernel.org/r/20190118175136.31341-7-mgorman@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: David Rientjes <rientjes@google.com>
Cc: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm, compaction: rename map_pages to split_map_pages
Mel Gorman [Tue, 5 Mar 2019 23:44:39 +0000 (15:44 -0800)]
mm, compaction: rename map_pages to split_map_pages

It's non-obvious that high-order free pages are split into order-0 pages
from the function name.  Fix it.

Link: http://lkml.kernel.org/r/20190118175136.31341-6-mgorman@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: David Rientjes <rientjes@google.com>
Cc: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm, compaction: remove unnecessary zone parameter in some instances
Mel Gorman [Tue, 5 Mar 2019 23:44:36 +0000 (15:44 -0800)]
mm, compaction: remove unnecessary zone parameter in some instances

A zone parameter is passed into a number of top-level compaction
functions despite the fact that it's already in compact_control.  This
is harmless but it did need an audit to check if zone actually ever
changes meaningfully.  This patches removes the parameter in a number of
top-level functions.  The change could be much deeper but this was
enough to briefly clarify the flow.

No functional change.

Link: http://lkml.kernel.org/r/20190118175136.31341-5-mgorman@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: David Rientjes <rientjes@google.com>
Cc: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm, compaction: remove last_migrated_pfn from compact_control
Mel Gorman [Tue, 5 Mar 2019 23:44:32 +0000 (15:44 -0800)]
mm, compaction: remove last_migrated_pfn from compact_control

The last_migrated_pfn field is a bit dubious as to whether it really
helps but either way, the information from it can be inferred without
increasing the size of compact_control so remove the field.

Link: http://lkml.kernel.org/r/20190118175136.31341-4-mgorman@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: David Rientjes <rientjes@google.com>
Cc: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm, compaction: rearrange compact_control
Mel Gorman [Tue, 5 Mar 2019 23:44:28 +0000 (15:44 -0800)]
mm, compaction: rearrange compact_control

compact_control spans two cache lines with write-intensive lines on
both.  Rearrange so the most write-intensive fields are in the same
cache line.  This has a negligible impact on the overall performance of
compaction and is more a tidying exercise than anything.

Link: http://lkml.kernel.org/r/20190118175136.31341-3-mgorman@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: David Rientjes <rientjes@google.com>
Cc: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm, compaction: shrink compact_control
Mel Gorman [Tue, 5 Mar 2019 23:44:25 +0000 (15:44 -0800)]
mm, compaction: shrink compact_control

Patch series "Increase success rates and reduce latency of compaction", v3.

This series reduces scan rates and success rates of compaction,
primarily by using the free lists to shorten scans, better controlling
of skip information and whether multiple scanners can target the same
block and capturing pageblocks before being stolen by parallel requests.
The series is based on mmotm from January 9th, 2019 with the previous
compaction series reverted.

I'm mostly using thpscale to measure the impact of the series.  The
benchmark creates a large file, maps it, faults it, punches holes in the
mapping so that the virtual address space is fragmented and then tries
to allocate THP.  It re-executes for different numbers of threads.  From
a fragmentation perspective, the workload is relatively benign but it
does stress compaction.

The overall impact on latencies for a 1-socket machine is

      baseline       patches
Amean     fault-both-3      3832.09 (   0.00%)     2748.56 *  28.28%*
Amean     fault-both-5      4933.06 (   0.00%)     4255.52 (  13.73%)
Amean     fault-both-7      7017.75 (   0.00%)     6586.93 (   6.14%)
Amean     fault-both-12    11610.51 (   0.00%)     9162.34 *  21.09%*
Amean     fault-both-18    17055.85 (   0.00%)    11530.06 *  32.40%*
Amean     fault-both-24    19306.27 (   0.00%)    17956.13 (   6.99%)
Amean     fault-both-30    22516.49 (   0.00%)    15686.47 *  30.33%*
Amean     fault-both-32    23442.93 (   0.00%)    16564.83 *  29.34%*

The allocation success rates are much improved

   baseline  patches
Percentage huge-3        85.99 (   0.00%)       97.96 (  13.92%)
Percentage huge-5        88.27 (   0.00%)       96.87 (   9.74%)
Percentage huge-7        85.87 (   0.00%)       94.53 (  10.09%)
Percentage huge-12       82.38 (   0.00%)       98.44 (  19.49%)
Percentage huge-18       83.29 (   0.00%)       99.14 (  19.04%)
Percentage huge-24       81.41 (   0.00%)       97.35 (  19.57%)
Percentage huge-30       80.98 (   0.00%)       98.05 (  21.08%)
Percentage huge-32       80.53 (   0.00%)       97.06 (  20.53%)

That's a nearly perfect allocation success rate.

The biggest impact is on the scan rates

Compaction migrate scanned    55893379    19341254
Compaction free scanned      474739990    11903963

The number of pages scanned for migration was reduced by 65% and the
free scanner was reduced by 97.5%.  So much less work in exchange for
lower latency and better success rates.

The series was also evaluated using a workload that heavily fragments
memory but the benefits there are also significant, albeit not
presented.

It was commented that we should be rethinking scanning entirely and to a
large extent I agree.  However, to achieve that you need a lot of this
series in place first so it's best to make the linear scanners as best
as possible before ripping them out.

This patch (of 22):

The isolate and migrate scanners should never isolate more than a
pageblock of pages so unsigned int is sufficient saving 8 bytes on a
64-bit build.

Link: http://lkml.kernel.org/r/20190118175136.31341-2-mgorman@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: David Rientjes <rientjes@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm/filemap: pass inclusive 'end_byte' parameter to filemap_range_has_page
zhengbin [Tue, 5 Mar 2019 23:44:21 +0000 (15:44 -0800)]
mm/filemap: pass inclusive 'end_byte' parameter to filemap_range_has_page

The 'end_byte' parameter of filemap_range_has_page is required to be
inclusive, so follow the rule.

Link: http://lkml.kernel.org/r/1548678679-18122-1-git-send-email-zhengbin13@huawei.com
Fixes: 6be96d3ad34a ("fs: return if direct I/O will trigger writeback")
Signed-off-by: zhengbin <zhengbin13@huawei.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Matthew Wilcox <willy@infradead.org>
Acked-by: Christoph Hellwig <hch@lst.de>
Cc: "Darrick J. Wong" <darrick.wong@oracle.com>
Cc: Amir Goldstein <amir73il@gmail.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Hou Tao <houtao1@huawei.com>
Cc: zhangyi (F) <yi.zhang@huawei.com>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm: shuffle GFP_* flags
Alexey Dobriyan [Tue, 5 Mar 2019 23:44:18 +0000 (15:44 -0800)]
mm: shuffle GFP_* flags

GFP_KERNEL is one of the most used constant but on archs like arm with
fixed length instruction some constants are more equal than the others.
Constants with tightly packed bits can be injected directly into
instruction stream:

   0:   e3a00d33        mov     r0, #3264       ; 0xcc0

Others require multiple instructions or even loading out of instruction
stream:

   0:   e3a000c0        mov     r0, #192        ; 0xc0
   4:   e3400060        movt    r0, #96 ; 0x60

Shuffle GFP_* flags so that GFP_KERNEL/GFP_ATOMIC + __GFP_ZERO bits are
close to each other.

Savings on arm configs are ~0.1%.

Link: http://lkml.kernel.org/r/20190109201838.GA9140@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm: swap: add comment for swap_vma_readahead
Yang Shi [Tue, 5 Mar 2019 23:44:15 +0000 (15:44 -0800)]
mm: swap: add comment for swap_vma_readahead

swap_vma_readahead()'s comment is missing, just add it.

Link: http://lkml.kernel.org/r/1546543673-108536-2-git-send-email-yang.shi@linux.alibaba.com
Signed-off-by: Yang Shi <yang.shi@linux.alibaba.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Tim Chen <tim.c.chen@intel.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Hugh Dickins <hughd@google.com
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm: swap: check if swap backing device is congested or not
Yang Shi [Tue, 5 Mar 2019 23:44:11 +0000 (15:44 -0800)]
mm: swap: check if swap backing device is congested or not

Swap readahead would read in a few pages regardless if the underlying
device is busy or not.  It may incur long waiting time if the device is
congested, and it may also exacerbate the congestion.

Use inode_read_congested() to check if the underlying device is busy or
not like what file page readahead does.  Get inode from
swap_info_struct.

Although we can add inode information in swap_address_space
(address_space->host), it may lead some unexpected side effect, i.e.  it
may break mapping_cap_account_dirty().  Using inode from
swap_info_struct seems simple and good enough.

Just does the check in vma_cluster_readahead() since
swap_vma_readahead() is just used for non-rotational device which much
less likely has congestion than traditional HDD.

Although swap slots may be consecutive on swap partition, it still may
be fragmented on swap file.  This check would help to reduce excessive
stall for such case.

The test with page_fault1 of will-it-scale (sometimes tracing may just
show runtest.py that is the wrapper script of page_fault1), which
basically launches NR_CPU threads to generate 128MB anonymous pages for
each thread, on my virtual machine with congested HDD shows long tail
latency is reduced significantly.

Without the patch
 page_fault1_thr-1490  [023]   129.311706: funcgraph_entry:      #57377.796 us |  do_swap_page();
 page_fault1_thr-1490  [023]   129.369103: funcgraph_entry:        5.642us   |  do_swap_page();
 page_fault1_thr-1490  [023]   129.369119: funcgraph_entry:      #1289.592 us |  do_swap_page();
 page_fault1_thr-1490  [023]   129.370411: funcgraph_entry:        4.957us   |  do_swap_page();
 page_fault1_thr-1490  [023]   129.370419: funcgraph_entry:        1.940us   |  do_swap_page();
 page_fault1_thr-1490  [023]   129.378847: funcgraph_entry:      #1411.385 us |  do_swap_page();
 page_fault1_thr-1490  [023]   129.380262: funcgraph_entry:        3.916us   |  do_swap_page();
 page_fault1_thr-1490  [023]   129.380275: funcgraph_entry:      #4287.751 us |  do_swap_page();

With the patch
      runtest.py-1417  [020]   301.925911: funcgraph_entry:      #9870.146 us |  do_swap_page();
      runtest.py-1417  [020]   301.935785: funcgraph_entry:        9.802us   |  do_swap_page();
      runtest.py-1417  [020]   301.935799: funcgraph_entry:        3.551us   |  do_swap_page();
      runtest.py-1417  [020]   301.935806: funcgraph_entry:        2.142us   |  do_swap_page();
      runtest.py-1417  [020]   301.935853: funcgraph_entry:        6.938us   |  do_swap_page();
      runtest.py-1417  [020]   301.935864: funcgraph_entry:        3.765us   |  do_swap_page();
      runtest.py-1417  [020]   301.935871: funcgraph_entry:        3.600us   |  do_swap_page();
      runtest.py-1417  [020]   301.935878: funcgraph_entry:        7.202us   |  do_swap_page();

[akpm@linux-foundation.org: code cleanup]
[yang.shi@linux.alibaba.com: add comment]
Link: http://lkml.kernel.org/r/bbc7bda7-62d0-df1a-23ef-d369e865bdca@linux.alibaba.com
Link: http://lkml.kernel.org/r/1546543673-108536-1-git-send-email-yang.shi@linux.alibaba.com
Signed-off-by: Yang Shi <yang.shi@linux.alibaba.com>
Acked-by: Tim Chen <tim.c.chen@intel.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Hugh Dickins <hughd@google.com
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm/filemap.c: remove redundant test from find_get_pages_contig
Matthew Wilcox [Tue, 5 Mar 2019 23:44:08 +0000 (15:44 -0800)]
mm/filemap.c: remove redundant test from find_get_pages_contig

After we establish a reference on the page, we check the pointer
continues to be in the correct position in i_pages.  Checking
page->index afterwards is unnecessary; if it were to change, then the
pointer to it from the page cache would also move.  The check used to be
done before grabbing a reference on the page which was racy (see commit
9cbb4cb21b19f ("mm: find_get_pages_contig fixlet")), but nobody noticed
that moving the check after grabbing the reference was redundant.

Link: http://lkml.kernel.org/r/20190107200224.13260-1-willy@infradead.org
Signed-off-by: Matthew Wilcox <willy@infradead.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm/memcontrol.c: use struct_size() in kmalloc()
Gustavo A. R. Silva [Tue, 5 Mar 2019 23:44:05 +0000 (15:44 -0800)]
mm/memcontrol.c: use struct_size() in kmalloc()

One of the more common cases of allocation size calculations is finding
the size of a structure that has a zero-sized array at the end, along
with memory for some number of elements for that array.  For example:

  struct foo {
      int stuff;
      void *entry[];
  };

  instance = kmalloc(sizeof(struct foo) + sizeof(void *) * count, GFP_KERNEL);

Instead of leaving these open-coded and prone to type mistakes, we can
now use the new struct_size() helper:

  instance = kmalloc(struct_size(instance, entry, count), GFP_KERNEL);

This code was detected with the help of Coccinelle.

Link: http://lkml.kernel.org/r/20190104183726.GA6374@embeddedor
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm: remove extra drain pages on pcp list
Wei Yang [Tue, 5 Mar 2019 23:44:01 +0000 (15:44 -0800)]
mm: remove extra drain pages on pcp list

In the current implementation, there are two places to isolate a range
of page: __offline_pages() and alloc_contig_range().  During this
procedure, it will drain pages on pcp list.

Below is a brief call flow:

  __offline_pages()/alloc_contig_range()
      start_isolate_page_range()
          set_migratetype_isolate()
              drain_all_pages()
      drain_all_pages()                 <--- A

This snippet shows the current logic is isolate and drain pcp list for
each pageblock and drain pcp list again for the whole range.

start_isolate_page_range is responsible for isolating the given pfn
range.  One part of that job is to make sure that also pages that are on
the allocator pcp lists are properly isolated.  Otherwise they could be
reused and the range wouldn't be completely isolated until the memory is
freed back.  While there is no strict guarantee here because pages might
get allocated at any time before drain_all_pages is called there doesn't
seem to be any strong demand for such a guarantee.

In any case, draining is already done at the isolation level and there
is no need to do it again later by start_isolate_page_range callers
(memory hotplug and CMA allocator currently).  Therefore remove
pointless draining in existing callers to make the code more clear and
functionally correct.

[mhocko@suse.com: provide a clearer changelog for the last two paragraphs]
Link: http://lkml.kernel.org/r/20190105233141.2329-1-richard.weiyang@gmail.com
Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agoarm64/mm: enable HugeTLB migration for contiguous bit HugeTLB pages
Anshuman Khandual [Tue, 5 Mar 2019 23:43:58 +0000 (15:43 -0800)]
arm64/mm: enable HugeTLB migration for contiguous bit HugeTLB pages

Let arm64 subscribe to the previously added framework in which
architecture can inform whether a given huge page size is supported for
migration.  This just overrides the default function
arch_hugetlb_migration_supported() and enables migration for all
possible HugeTLB page sizes on arm64.

With this, HugeTLB migration support on arm64 now covers all possible
HugeTLB options.

          CONT PTE    PMD    CONT PMD    PUD
          --------    ---    --------    ---
  4K:        64K      2M        32M      1G
  16K:        2M     32M         1G
  64K:        2M    512M        16G

Link: http://lkml.kernel.org/r/1545121450-1663-6-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Reviewed-by: Steve Capper <steve.capper@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agoarm64/mm: enable HugeTLB migration
Anshuman Khandual [Tue, 5 Mar 2019 23:43:55 +0000 (15:43 -0800)]
arm64/mm: enable HugeTLB migration

Let arm64 subscribe to generic HugeTLB page migration framework.  Right
now this only works on the following PMD and PUD level HugeTLB page
sizes with various kernel base page size combinations.

         CONT PTE    PMD    CONT PMD    PUD
         --------    ---    --------    ---
  4K:         NA     2M         NA      1G
  16K:        NA    32M         NA
  64K:        NA   512M         NA

Link: http://lkml.kernel.org/r/1545121450-1663-5-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Reviewed-by: Steve Capper <steve.capper@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm/hugetlb: enable arch specific huge page size support for migration
Anshuman Khandual [Tue, 5 Mar 2019 23:43:51 +0000 (15:43 -0800)]
mm/hugetlb: enable arch specific huge page size support for migration

Architectures like arm64 have HugeTLB page sizes which are different
than generic sizes at PMD, PUD, PGD level and implemented via contiguous
bits.  At present these special size HugeTLB pages cannot be identified
through macros like (PMD|PUD|PGDIR)_SHIFT and hence chosen not be
migrated.

Enabling migration support for these special HugeTLB page sizes along
with the generic ones (PMD|PUD|PGD) would require identifying all of
them on a given platform.  A platform specific hook can precisely
enumerate all huge page sizes supported for migration.  Instead of
comparing against standard huge page orders let
hugetlb_migration_support() function call a platform hook
arch_hugetlb_migration_support().  Default definition for the platform
hook maintains existing semantics which checks standard huge page order.
But an architecture can choose to override the default and provide
support for a comprehensive set of huge page sizes.

Link: http://lkml.kernel.org/r/1545121450-1663-4-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Reviewed-by: Steve Capper <steve.capper@arm.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm/hugetlb: enable PUD level huge page migration
Anshuman Khandual [Tue, 5 Mar 2019 23:43:48 +0000 (15:43 -0800)]
mm/hugetlb: enable PUD level huge page migration

Architectures like arm64 have PUD level HugeTLB pages for certain configs
(1GB huge page is PUD based on ARM64_4K_PAGES base page size) that can
be enabled for migration.  It can be achieved through checking for
PUD_SHIFT order based HugeTLB pages during migration.

Link: http://lkml.kernel.org/r/1545121450-1663-3-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Reviewed-by: Steve Capper <steve.capper@arm.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm/hugetlb: distinguish between migratability and movability
Anshuman Khandual [Tue, 5 Mar 2019 23:43:44 +0000 (15:43 -0800)]
mm/hugetlb: distinguish between migratability and movability

Patch series "arm64/mm: Enable HugeTLB migration", v4.

This patch series enables HugeTLB migration support for all supported
huge page sizes at all levels including contiguous bit implementation.
Following HugeTLB migration support matrix has been enabled with this
patch series.  All permutations have been tested except for the 16GB.

           CONT PTE    PMD    CONT PMD    PUD
           --------    ---    --------    ---
  4K:         64K     2M         32M     1G
  16K:         2M    32M          1G
  64K:         2M   512M         16G

First the series adds migration support for PUD based huge pages.  It
then adds a platform specific hook to query an architecture if a given
huge page size is supported for migration while also providing a default
fallback option preserving the existing semantics which just checks for
(PMD|PUD|PGDIR)_SHIFT macros.  The last two patches enables HugeTLB
migration on arm64 and subscribe to this new platform specific hook by
defining an override.

The second patch differentiates between movability and migratability
aspects of huge pages and implements hugepage_movable_supported() which
can then be used during allocation to decide whether to place the huge
page in movable zone or not.

This patch (of 5):

During huge page allocation it's migratability is checked to determine
if it should be placed under movable zones with GFP_HIGHUSER_MOVABLE.
But the movability aspect of the huge page could depend on other factors
than just migratability.  Movability in itself is a distinct property
which should not be tied with migratability alone.

This differentiates these two and implements an enhanced movability check
which also considers huge page size to determine if it is feasible to be
placed under a movable zone.  At present it just checks for gigantic pages
but going forward it can incorporate other enhanced checks.

Link: http://lkml.kernel.org/r/1545121450-1663-2-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Steve Capper <steve.capper@arm.com>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Suggested-by: Michal Hocko <mhocko@kernel.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm: remove sysctl_extfrag_handler()
Matthew Wilcox [Tue, 5 Mar 2019 23:43:41 +0000 (15:43 -0800)]
mm: remove sysctl_extfrag_handler()

sysctl_extfrag_handler() neglects to propagate the return value from
proc_dointvec_minmax() to its caller.  It's a wrapper that doesn't need
to exist, so just use proc_dointvec_minmax() directly.

Link: http://lkml.kernel.org/r/20190104032557.3056-1-willy@infradead.org
Signed-off-by: Matthew Wilcox <willy@infradead.org>
Reported-by: Aditya Pakki <pakki001@umn.edu>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agoselftests/vm: add script helper for CONFIG_TEST_VMALLOC_MODULE
Uladzislau Rezki (Sony) [Tue, 5 Mar 2019 23:43:37 +0000 (15:43 -0800)]
selftests/vm: add script helper for CONFIG_TEST_VMALLOC_MODULE

Add the test script for the kernel test driver to analyse vmalloc
allocator for benchmarking and stressing purposes.  It is just a kernel
module loader.  You can specify and pass different parameters in order
to investigate allocations behaviour.  See "usage" output for more
details.

Also add basic vmalloc smoke test to the "run_vmtests" suite.

Link: http://lkml.kernel.org/r/20190103142108.20744-4-urezki@gmail.com
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Reviewed-by: Shuah Khan <shuah@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Oleksiy Avramchenko <oleksiy.avramchenko@sonymobile.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agovmalloc: add test driver to analyse vmalloc allocator
Uladzislau Rezki (Sony) [Tue, 5 Mar 2019 23:43:34 +0000 (15:43 -0800)]
vmalloc: add test driver to analyse vmalloc allocator

This adds a new kernel module for analysis of vmalloc allocator.  It is
only enabled as a module.  There are two main reasons this module should
be used for: performance evaluation and stressing of vmalloc subsystem.

It consists of several test cases.  As of now there are 8.  The module
has five parameters we can specify to change its the behaviour.

1) run_test_mask - set of tests to be run

id: 1,   name: fix_size_alloc_test
id: 2,   name: full_fit_alloc_test
id: 4,   name: long_busy_list_alloc_test
id: 8,   name: random_size_alloc_test
id: 16,  name: fix_align_alloc_test
id: 32,  name: random_size_align_alloc_test
id: 64,  name: align_shift_alloc_test
id: 128, name: pcpu_alloc_test

By default all tests are in run test mask.  If you want to select some
specific tests it is possible to pass the mask.  For example for first,
second and fourth tests we go 11 value.

2) test_repeat_count - how many times each test should be repeated
By default it is one time per test. It is possible to pass any number.
As high the value is the test duration gets increased.

3) test_loop_count - internal test loop counter. By default it is set
to 1000000.

4) single_cpu_test - use one CPU to run the tests
By default this parameter is set to false. It means that all online
CPUs execute tests. By setting it to 1, the tests are executed by
first online CPU only.

5) sequential_test_order - run tests in sequential order
By default this parameter is set to false. It means that before running
tests the order is shuffled. It is possible to make it sequential, just
set it to 1.

Performance analysis:
In order to evaluate performance of vmalloc allocations, usually it
makes sense to use only one CPU that runs tests, use sequential order,
number of repeat tests can be different as well as set of test mask.

For example if we want to run all tests, to use one CPU and repeat each
test 3 times. Insert the module passing following parameters:

single_cpu_test=1 sequential_test_order=1 test_repeat_count=3

with following output:

<snip>
Summary: fix_size_alloc_test passed: 3 failed: 0 repeat: 3 loops: 1000000 avg: 901177 usec
Summary: full_fit_alloc_test passed: 3 failed: 0 repeat: 3 loops: 1000000 avg: 1039341 usec
Summary: long_busy_list_alloc_test passed: 3 failed: 0 repeat: 3 loops: 1000000 avg: 11775763 usec
Summary: random_size_alloc_test passed 3: failed: 0 repeat: 3 loops: 1000000 avg: 6081992 usec
Summary: fix_align_alloc_test passed: 3 failed: 0 repeat: 3, loops: 1000000 avg: 2003712 usec
Summary: random_size_align_alloc_test passed: 3 failed: 0 repeat: 3 loops: 1000000 avg: 2895689 usec
Summary: align_shift_alloc_test passed: 0 failed: 3 repeat: 3 loops: 1000000 avg: 573 usec
Summary: pcpu_alloc_test passed: 3 failed: 0 repeat: 3 loops: 1000000 avg: 95802 usec
All test took CPU0=192945605995 cycles
<snip>

The align_shift_alloc_test is expected to be failed.

Stressing:
In order to stress the vmalloc subsystem we run all available test cases
on all available CPUs simultaneously. In order to prevent constant behaviour
pattern, the test cases array is shuffled by default to randomize the order
of test execution.

For example if we want to run all tests(default), use all online CPUs(default)
with shuffled order(default) and to repeat each test 30 times. The command
would be like:

modprobe vmalloc_test test_repeat_count=30

Expected results are the system is alive, there are no any BUG_ONs or Kernel
Panics the tests are completed, no memory leaks.

[urezki@gmail.com: fix 32-bit builds]
Link: http://lkml.kernel.org/r/20190106214839.ffvjvmrn52uqog7k@pc636
[urezki@gmail.com: make CONFIG_TEST_VMALLOC depend on CONFIG_MMU]
Link: http://lkml.kernel.org/r/20190219085441.s6bg2gpy4esny5vw@pc636
Link: http://lkml.kernel.org/r/20190103142108.20744-3-urezki@gmail.com
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Oleksiy Avramchenko <oleksiy.avramchenko@sonymobile.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agovmalloc: export __vmalloc_node_range for CONFIG_TEST_VMALLOC_MODULE
Uladzislau Rezki (Sony) [Tue, 5 Mar 2019 23:43:30 +0000 (15:43 -0800)]
vmalloc: export __vmalloc_node_range for CONFIG_TEST_VMALLOC_MODULE

Export __vmaloc_node_range() function if CONFIG_TEST_VMALLOC_MODULE is
enabled.  Some test cases in vmalloc test suite module require and make
use of that function.  Please note, that it is not supposed to be used
for other purposes.

We need it only for performance analysis, stressing and stability check
of vmalloc allocator.

Link: http://lkml.kernel.org/r/20190103142108.20744-2-urezki@gmail.com
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Oleksiy Avramchenko <oleksiy.avramchenko@sonymobile.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm/vmalloc: pass VM_USERMAP flags directly to __vmalloc_node_range()
Roman Penyaev [Tue, 5 Mar 2019 23:43:27 +0000 (15:43 -0800)]
mm/vmalloc: pass VM_USERMAP flags directly to __vmalloc_node_range()

vmalloc_user*() calls differ from normal vmalloc() only in that they set
VM_USERMAP flags for the area.  During the whole history of vmalloc.c
changes now it is possible simply to pass VM_USERMAP flags directly to
__vmalloc_node_range() call instead of finding the area (which obviously
takes time) after the allocation.

Link: http://lkml.kernel.org/r/20190103145954.16942-4-rpenyaev@suse.de
Signed-off-by: Roman Penyaev <rpenyaev@suse.de>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Joe Perches <joe@perches.com>
Cc: "Luis R. Rodriguez" <mcgrof@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm/vmalloc: do not call kmemleak_free() on not yet accounted memory
Roman Penyaev [Tue, 5 Mar 2019 23:43:24 +0000 (15:43 -0800)]
mm/vmalloc: do not call kmemleak_free() on not yet accounted memory

__vmalloc_area_node() calls vfree() on error path, which in turn calls
kmemleak_free(), but area is not yet accounted by kmemleak_vmalloc().

Link: http://lkml.kernel.org/r/20190103145954.16942-3-rpenyaev@suse.de
Signed-off-by: Roman Penyaev <rpenyaev@suse.de>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Joe Perches <joe@perches.com>
Cc: "Luis R. Rodriguez" <mcgrof@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm/vmalloc: fix size check for remap_vmalloc_range_partial()
Roman Penyaev [Tue, 5 Mar 2019 23:43:20 +0000 (15:43 -0800)]
mm/vmalloc: fix size check for remap_vmalloc_range_partial()

When VM_NO_GUARD is not set area->size includes adjacent guard page,
thus for correct size checking get_vm_area_size() should be used, but
not area->size.

This fixes possible kernel oops when userspace tries to mmap an area on
1 page bigger than was allocated by vmalloc_user() call: the size check
inside remap_vmalloc_range_partial() accounts non-existing guard page
also, so check successfully passes but vmalloc_to_page() returns NULL
(guard page does not physically exist).

The following code pattern example should trigger an oops:

  static int oops_mmap(struct file *file, struct vm_area_struct *vma)
  {
        void *mem;

        mem = vmalloc_user(4096);
        BUG_ON(!mem);
        /* Do not care about mem leak */

        return remap_vmalloc_range(vma, mem, 0);
  }

And userspace simply mmaps size + PAGE_SIZE:

  mmap(NULL, 8192, PROT_WRITE|PROT_READ, MAP_PRIVATE, fd, 0);

Possible candidates for oops which do not have any explicit size
checks:

   *** drivers/media/usb/stkwebcam/stk-webcam.c:
   v4l_stk_mmap[789]   ret = remap_vmalloc_range(vma, sbuf->buffer, 0);

Or the following one:

   *** drivers/video/fbdev/core/fbmem.c
   static int
   fb_mmap(struct file *file, struct vm_area_struct * vma)
        ...
        res = fb->fb_mmap(info, vma);

Where fb_mmap callback calls remap_vmalloc_range() directly without any
explicit checks:

   *** drivers/video/fbdev/vfb.c
   static int vfb_mmap(struct fb_info *info,
             struct vm_area_struct *vma)
   {
       return remap_vmalloc_range(vma, (void *)info->fix.smem_start, vma->vm_pgoff);
   }

Link: http://lkml.kernel.org/r/20190103145954.16942-2-rpenyaev@suse.de
Signed-off-by: Roman Penyaev <rpenyaev@suse.de>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Joe Perches <joe@perches.com>
Cc: "Luis R. Rodriguez" <mcgrof@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm/vmalloc.c: make vmalloc_32_user() align base kernel virtual address to SHMLBA
Roman Penyaev [Tue, 5 Mar 2019 23:43:17 +0000 (15:43 -0800)]
mm/vmalloc.c: make vmalloc_32_user() align base kernel virtual address to SHMLBA

This patch repeats the original one from David S Miller:

  2dca6999eed5 ("mm, perf_event: Make vmalloc_user() align base kernel virtual address to SHMLBA")

but for missed vmalloc_32_user() case, which also requires correct
alignment of virtual address on kernel side to avoid D-caches aliases.
A bit of copy-paste from original patch to recover in memory of what is
all about:

  When a vmalloc'd area is mmap'd into userspace, some kind of
  co-ordination is necessary for this to work on platforms with cpu
  D-caches which can have aliases.

  Otherwise kernel side writes won't be seen properly in userspace and
  vice versa.

  If the kernel side mapping and the user side one have the same
  alignment, modulo SHMLBA, this can work as long as VM_SHARED is shared
  of VMA and for all current users this is true. VM_SHARED will force
  SHMLBA alignment of the user side mmap on platforms with D-cache
  aliasing matters.

  David S. Miller

> What are the user-visible runtime effects of this change?

In simple words: proper alignment avoids possible difference in data,
seen by different virtual mapings: userspace and kernel in our case.
I.e. userspace reads cache line A, kernel writes to cache line B.  Both
cache lines correspond to the same physical memory (thus aliases).

So this should fix data corruption for archs with vivt and vipt caches,
e.g. armv6.  Personally I've never worked with this archs, I just
spotted the strange difference in code: for one case we do alignment,
for another - not.  I have a strong feeling that David simply missed
vmalloc_32_user() case.

>
> Is a -stable backport needed?

No, I do not think so.  The only one user of vmalloc_32_user() is
virtual frame buffer device drivers/video/fbdev/vfb.c, which has in the
description "The main use of this frame buffer device is testing and
debugging the frame buffer subsystem.  Do NOT enable it for normal
systems!".

And it seems to me that this vfb.c does not need 32bit addressable pages
(vmalloc_32_user() case), because it is virtual device and should not
care about things like dma32 zones, etc.  Probably is better to clean
the code and switch vfb.c from vmalloc_32_user() to vmalloc_user() case
and wipe out vmalloc_32_user() from vmalloc.c completely.  But I'm not
very much sure that this is worth to do, that's so minor, so we can
leave it as is.

Link: http://lkml.kernel.org/r/20190108110944.23591-1-rpenyaev@suse.de
Signed-off-by: Roman Penyaev <rpenyaev@suse.de>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Michal Hocko <mhocko@suse.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomemcg: localize memcg_kmem_enabled() check
Shakeel Butt [Tue, 5 Mar 2019 23:43:13 +0000 (15:43 -0800)]
memcg: localize memcg_kmem_enabled() check

Move the memcg_kmem_enabled() checks into memcg kmem charge/uncharge
functions, so, the users don't have to explicitly check that condition.

This is purely code cleanup patch without any functional change.  Only
the order of checks in memcg_charge_slab() can potentially be changed
but the functionally it will be same.  This should not matter as
memcg_charge_slab() is not in the hot path.

Link: http://lkml.kernel.org/r/20190103161203.162375-1-shakeelb@google.com
Signed-off-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Roman Gushchin <guro@fb.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm, slub: make the comment of put_cpu_partial() complete
Wei Yang [Tue, 5 Mar 2019 23:43:10 +0000 (15:43 -0800)]
mm, slub: make the comment of put_cpu_partial() complete

There are two cases when put_cpu_partial() is invoked.

    * __slab_free
    * get_partial_node

This patch just makes it cover these two cases.

Link: http://lkml.kernel.org/r/20181025094437.18951-3-richard.weiyang@gmail.com
Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
Acked-by: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm: reuse only-pte-mapped KSM page in do_wp_page()
Kirill Tkhai [Tue, 5 Mar 2019 23:43:06 +0000 (15:43 -0800)]
mm: reuse only-pte-mapped KSM page in do_wp_page()

Add an optimization for KSM pages almost in the same way that we have
for ordinary anonymous pages.  If there is a write fault in a page,
which is mapped to an only pte, and it is not related to swap cache; the
page may be reused without copying its content.

[ Note that we do not consider PageSwapCache() pages at least for now,
  since we don't want to complicate __get_ksm_page(), which has nice
  optimization based on this (for the migration case). Currenly it is
  spinning on PageSwapCache() pages, waiting for when they have
  unfreezed counters (i.e., for the migration finish). But we don't want
  to make it also spinning on swap cache pages, which we try to reuse,
  since there is not a very high probability to reuse them. So, for now
  we do not consider PageSwapCache() pages at all. ]

So in reuse_ksm_page() we check for 1) PageSwapCache() and 2)
page_stable_node(), to skip a page, which KSM is currently trying to
link to stable tree.  Then we do page_ref_freeze() to prohibit KSM to
merge one more page into the page, we are reusing.  After that, nobody
can refer to the reusing page: KSM skips !PageSwapCache() pages with
zero refcount; and the protection against of all other participants is
the same as for reused ordinary anon pages pte lock, page lock and
mmap_sem.

[akpm@linux-foundation.org: replace BUG_ON()s with WARN_ON()s]
Link: http://lkml.kernel.org/r/154471491016.31352.1168978849911555609.stgit@localhost.localdomain
Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Reviewed-by: Yang Shi <yang.shi@linux.alibaba.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Hugh Dickins <hughd@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Christian Koenig <christian.koenig@amd.com>
Cc: Claudio Imbrenda <imbrenda@linux.vnet.ibm.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agotools/: replace open encodings for NUMA_NO_NODE
Stephen Rothwell [Tue, 5 Mar 2019 23:43:01 +0000 (15:43 -0800)]
tools/: replace open encodings for NUMA_NO_NODE

This replaces all open encodings in tools with NUMA_NO_NODE.  Also
linux/numa.h is now needed for the perf build.

[sfr@canb.auug.org.au: fix for replace open encodings for NUMA_NO_NODE]
Link: http://lkml.kernel.org/r/20190108131141.730e9c4f@canb.auug.org.au
Link: http://lkml.kernel.org/r/1545127933-10711-3-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: David Hildenbrand <david@redhat.com>
Cc: Doug Ledford <dledford@redhat.com> [drivers/infiniband]
Cc: Hans Verkuil <hverkuil@xs4all.nl>
Cc: Jeff Kirsher <jeffrey.t.kirsher@intel.com> [ixgbe]
Cc: Jens Axboe <axboe@kernel.dk> [mtip32xx]
Cc: Joseph Qi <jiangqi903@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au> [powerpc]
Cc: Vinod Koul <vkoul@kernel.org> [dmaengine.c]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm: replace all open encodings for NUMA_NO_NODE
Anshuman Khandual [Tue, 5 Mar 2019 23:42:58 +0000 (15:42 -0800)]
mm: replace all open encodings for NUMA_NO_NODE

Patch series "Replace all open encodings for NUMA_NO_NODE", v3.

All these places for replacement were found by running the following
grep patterns on the entire kernel code.  Please let me know if this
might have missed some instances.  This might also have replaced some
false positives.  I will appreciate suggestions, inputs and review.

1. git grep "nid == -1"
2. git grep "node == -1"
3. git grep "nid = -1"
4. git grep "node = -1"

This patch (of 2):

At present there are multiple places where invalid node number is
encoded as -1.  Even though implicitly understood it is always better to
have macros in there.  Replace these open encodings for an invalid node
number with the global macro NUMA_NO_NODE.  This helps remove NUMA
related assumptions like 'invalid node' from various places redirecting
them to a common definition.

Link: http://lkml.kernel.org/r/1545127933-10711-2-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Acked-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> [ixgbe]
Acked-by: Jens Axboe <axboe@kernel.dk> [mtip32xx]
Acked-by: Vinod Koul <vkoul@kernel.org> [dmaengine.c]
Acked-by: Michael Ellerman <mpe@ellerman.id.au> [powerpc]
Acked-by: Doug Ledford <dledford@redhat.com> [drivers/infiniband]
Cc: Joseph Qi <jiangqi903@gmail.com>
Cc: Hans Verkuil <hverkuil@xs4all.nl>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm/vmalloc.c: don't dereference possible NULL pointer in __vunmap()
Liviu Dudau [Tue, 5 Mar 2019 23:42:54 +0000 (15:42 -0800)]
mm/vmalloc.c: don't dereference possible NULL pointer in __vunmap()

find_vmap_area() can return a NULL pointer and we're going to
dereference it without checking it first.  Use the existing
find_vm_area() function which does exactly what we want and checks for
the NULL pointer.

Link: http://lkml.kernel.org/r/20181228171009.22269-1-liviu@dudau.co.uk
Fixes: f3c01d2f3ade ("mm: vmalloc: avoid racy handling of debugobjects in vunmap")
Signed-off-by: Liviu Dudau <liviu@dudau.co.uk>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Chintan Pandya <cpandya@codeaurora.org>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agoPM/Hibernate: exclude all PageOffline() pages
David Hildenbrand [Tue, 5 Mar 2019 23:42:50 +0000 (15:42 -0800)]
PM/Hibernate: exclude all PageOffline() pages

The content of pages that are marked PG_offline is not of interest (e.g.
inflated by a balloon driver), let's skip these pages.

In saveable_highmem_page(), move the PageReserved() check to a new check
along with the PageOffline() check to separate it from the swsusp
checks.

[david@redhat.com: v2]
Link: http://lkml.kernel.org/r/20181122100627.5189-9-david@redhat.com
Link: http://lkml.kernel.org/r/20181119101616.8901-9-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Len Brown <len.brown@intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Christian Hansen <chansen3@cisco.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Juergen Gross <jgross@suse.com>
Cc: Julien Freche <jfreche@vmware.com>
Cc: Kairui Song <kasong@redhat.com>
Cc: Kazuhito Hagio <k-hagio@ab.jp.nec.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Lianbo Jiang <lijiang@redhat.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Miles Chen <miles.chen@mediatek.com>
Cc: Nadav Amit <namit@vmware.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Omar Sandoval <osandov@fb.com>
Cc: Pankaj gupta <pagupta@redhat.com>
Cc: Pavel Tatashin <pasha.tatashin@oracle.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Xavier Deguillard <xdeguillard@vmware.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agoPM/Hibernate: use pfn_to_online_page()
David Hildenbrand [Tue, 5 Mar 2019 23:42:45 +0000 (15:42 -0800)]
PM/Hibernate: use pfn_to_online_page()

Let's use pfn_to_online_page() instead of pfn_to_page() when checking
for saveable pages to not save/restore offline memory sections.

Link: http://lkml.kernel.org/r/20181119101616.8901-8-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Suggested-by: Michal Hocko <mhocko@kernel.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Len Brown <len.brown@intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Christian Hansen <chansen3@cisco.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Juergen Gross <jgross@suse.com>
Cc: Julien Freche <jfreche@vmware.com>
Cc: Kairui Song <kasong@redhat.com>
Cc: Kazuhito Hagio <k-hagio@ab.jp.nec.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Lianbo Jiang <lijiang@redhat.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Miles Chen <miles.chen@mediatek.com>
Cc: Nadav Amit <namit@vmware.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Omar Sandoval <osandov@fb.com>
Cc: Pankaj gupta <pagupta@redhat.com>
Cc: Pavel Tatashin <pasha.tatashin@oracle.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Xavier Deguillard <xdeguillard@vmware.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agovmw_balloon: mark inflated pages PG_offline
David Hildenbrand [Tue, 5 Mar 2019 23:42:41 +0000 (15:42 -0800)]
vmw_balloon: mark inflated pages PG_offline

Mark inflated and never onlined pages PG_offline, to tell the world that
the content is stale and should not be dumped.

[david@redhat.com: use vmballoon_page_in_frames more widely]
Link: http://lkml.kernel.org/r/20181122100627.5189-7-david@redhat.com
Link: http://lkml.kernel.org/r/20181119101616.8901-7-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Acked-by: Nadav Amit <namit@vmware.com>
Cc: Xavier Deguillard <xdeguillard@vmware.com>
Cc: Nadav Amit <namit@vmware.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Julien Freche <jfreche@vmware.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Christian Hansen <chansen3@cisco.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kairui Song <kasong@redhat.com>
Cc: Kazuhito Hagio <k-hagio@ab.jp.nec.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Len Brown <len.brown@intel.com>
Cc: Lianbo Jiang <lijiang@redhat.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Miles Chen <miles.chen@mediatek.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Omar Sandoval <osandov@fb.com>
Cc: Pankaj gupta <pagupta@redhat.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Pavel Tatashin <pasha.tatashin@oracle.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agohv_balloon: mark inflated pages PG_offline
David Hildenbrand [Tue, 5 Mar 2019 23:42:36 +0000 (15:42 -0800)]
hv_balloon: mark inflated pages PG_offline

Mark inflated and never onlined pages PG_offline, to tell the world that
the content is stale and should not be dumped.

Link: http://lkml.kernel.org/r/20181119101616.8901-6-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Acked-by: Pankaj gupta <pagupta@redhat.com>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Kairui Song <kasong@redhat.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Christian Hansen <chansen3@cisco.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Juergen Gross <jgross@suse.com>
Cc: Julien Freche <jfreche@vmware.com>
Cc: Kazuhito Hagio <k-hagio@ab.jp.nec.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Len Brown <len.brown@intel.com>
Cc: Lianbo Jiang <lijiang@redhat.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Miles Chen <miles.chen@mediatek.com>
Cc: Nadav Amit <namit@vmware.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Omar Sandoval <osandov@fb.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Pavel Tatashin <pasha.tatashin@oracle.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Xavier Deguillard <xdeguillard@vmware.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agoxen/balloon: mark inflated pages PG_offline
David Hildenbrand [Tue, 5 Mar 2019 23:42:32 +0000 (15:42 -0800)]
xen/balloon: mark inflated pages PG_offline

Mark inflated and never onlined pages PG_offline, to tell the world that
the content is stale and should not be dumped.

Link: http://lkml.kernel.org/r/20181119101616.8901-5-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Christian Hansen <chansen3@cisco.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Julien Freche <jfreche@vmware.com>
Cc: Kairui Song <kasong@redhat.com>
Cc: Kazuhito Hagio <k-hagio@ab.jp.nec.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Len Brown <len.brown@intel.com>
Cc: Lianbo Jiang <lijiang@redhat.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Miles Chen <miles.chen@mediatek.com>
Cc: Nadav Amit <namit@vmware.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Omar Sandoval <osandov@fb.com>
Cc: Pankaj gupta <pagupta@redhat.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Pavel Tatashin <pasha.tatashin@oracle.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Xavier Deguillard <xdeguillard@vmware.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agokexec: export PG_offline to VMCOREINFO
David Hildenbrand [Tue, 5 Mar 2019 23:42:27 +0000 (15:42 -0800)]
kexec: export PG_offline to VMCOREINFO

Right now, pages inflated as part of a balloon driver will be dumped by
dump tools like makedumpfile.  While XEN is able to check in the crash
kernel whether a certain pfn is actuall backed by memory in the
hypervisor (see xen_oldmem_pfn_is_ram) and optimize this case, dumps of
other balloon inflated memory will essentially result in zero pages
getting allocated by the hypervisor and the dump getting filled with
this data.

The allocation and reading of zero pages can directly be avoided if a
dumping tool could know which pages only contain stale information not
to be dumped.

We now have PG_offline which can be (and already is by virtio-balloon)
used for marking pages as logically offline.  Follow up patches will
make use of this flag also in other balloon implementations.

Let's export PG_offline via PAGE_OFFLINE_MAPCOUNT_VALUE, so makedumpfile
can directly skip pages that are logically offline and the content
therefore stale.

Please note that this is also helpful for a problem we were seeing under
Hyper-V: Dumping logically offline memory (pages kept fake offline while
onlining a section via online_page_callback) would under some condicions
result in a kernel panic when dumping them.

Link: http://lkml.kernel.org/r/20181119101616.8901-4-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Dave Young <dyoung@redhat.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Omar Sandoval <osandov@fb.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Lianbo Jiang <lijiang@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Kazuhito Hagio <k-hagio@ab.jp.nec.com>
Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Christian Hansen <chansen3@cisco.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Juergen Gross <jgross@suse.com>
Cc: Julien Freche <jfreche@vmware.com>
Cc: Kairui Song <kasong@redhat.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Len Brown <len.brown@intel.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Miles Chen <miles.chen@mediatek.com>
Cc: Nadav Amit <namit@vmware.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Pankaj gupta <pagupta@redhat.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Pavel Tatashin <pasha.tatashin@oracle.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Xavier Deguillard <xdeguillard@vmware.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm: convert PG_balloon to PG_offline
David Hildenbrand [Tue, 5 Mar 2019 23:42:23 +0000 (15:42 -0800)]
mm: convert PG_balloon to PG_offline

PG_balloon was introduced to implement page migration/compaction for
pages inflated in virtio-balloon.  Nowadays, it is only a marker that a
page is part of virtio-balloon and therefore logically offline.

We also want to make use of this flag in other balloon drivers - for
inflated pages or when onlining a section but keeping some pages offline
(e.g.  used right now by XEN and Hyper-V via set_online_page_callback()).

We are going to expose this flag to dump tools like makedumpfile.  But
instead of exposing PG_balloon, let's generalize the concept of marking
pages as logically offline, so it can be reused for other purposes later
on.

Rename PG_balloon to PG_offline.  This is an indicator that the page is
logically offline, the content stale and that it should not be touched
(e.g.  a hypervisor would have to allocate backing storage in order for
the guest to dump an unused page).  We can then e.g.  exclude such pages
from dumps.

We replace and reuse KPF_BALLOON (23), as this shouldn't really harm
(and for now the semantics stay the same).  In following patches, we
will make use of this bit also in other balloon drivers.  While at it,
document PGTABLE.

[akpm@linux-foundation.org: fix comment text, per David]
Link: http://lkml.kernel.org/r/20181119101616.8901-3-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Acked-by: Konstantin Khlebnikov <koct9i@gmail.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Pankaj gupta <pagupta@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Christian Hansen <chansen3@cisco.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Pavel Tatashin <pasha.tatashin@oracle.com>
Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Miles Chen <miles.chen@mediatek.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Kazuhito Hagio <k-hagio@ab.jp.nec.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Julien Freche <jfreche@vmware.com>
Cc: Kairui Song <kasong@redhat.com>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Len Brown <len.brown@intel.com>
Cc: Lianbo Jiang <lijiang@redhat.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Nadav Amit <namit@vmware.com>
Cc: Omar Sandoval <osandov@fb.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Xavier Deguillard <xdeguillard@vmware.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm: balloon: update comment about isolation/migration/compaction
David Hildenbrand [Tue, 5 Mar 2019 23:42:18 +0000 (15:42 -0800)]
mm: balloon: update comment about isolation/migration/compaction

Patch series "mm/kdump: allow to exclude pages that are logically
offline"

Right now, pages inflated as part of a balloon driver will be dumped by
dump tools like makedumpfile.  While XEN is able to check in the crash
kernel whether a certain pfn is actuall backed by memory in the
hypervisor (see xen_oldmem_pfn_is_ram) and optimize this case, dumps of
virtio-balloon, hv-balloon and VMWare balloon inflated memory will
essentially result in zero pages getting allocated by the hypervisor and
the dump getting filled with this data.

The allocation and reading of zero pages can directly be avoided if a
dumping tool could know which pages only contain stale information not
to be dumped.

Also for XEN, calling into the kernel and asking the hypervisor if a pfn
is backed can be avoided if the duming tool would skip such pages right
from the beginning.

Dumping tools have no idea whether a given page is part of a balloon
driver and shall not be dumped.  Esp.  PG_reserved cannot be used for
that purpose as all memory allocated during early boot is also
PG_reserved, see discussion at [1].  So some other way of indication is
required and a new page flag is frowned upon.

We have PG_balloon (MAPCOUNT value), which is essentially unused now.  I
suggest renaming it to something more generic (PG_offline) to mark pages
as logically offline.  This flag can than e.g.  also be used by
virtio-mem in the future to mark subsections as offline.  Or by other
code that wants to put pages logically offline (e.g.  later maybe
poisoned pages that shall no longer be used).

This series converts PG_balloon to PG_offline, allows dumping tools to
query the value to detect such pages and marks pages in the hv-balloon
and XEN balloon properly as PG_offline.  Note that virtio-balloon
already set pages to PG_balloon (and now PG_offline).

Please note that this is also helpful for a problem we were seeing under
Hyper-V: Dumping logically offline memory (pages kept fake offline while
onlining a section via online_page_callback) would under some condicions
result in a kernel panic when dumping them.

As I don't have access to neither XEN nor Hyper-V nor VMWare
installations, this was only tested with the virtio-balloon and pages
were properly skipped when dumping.  I'll also attach the makedumpfile
patch to this series.

[1] https://lkml.org/lkml/2018/7/20/566

This patch (of 8):

Commit b1123ea6d3b3 ("mm: balloon: use general non-lru movable page
feature") reworked balloon handling to make use of the general non-lru
movable page feature.  The big comment block in balloon_compaction.h
contains quite some outdated information.  Let's fix this.

Link: http://lkml.kernel.org/r/20181119101616.8901-2-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Christian Hansen <chansen3@cisco.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Juergen Gross <jgross@suse.com>
Cc: Julien Freche <jfreche@vmware.com>
Cc: Kairui Song <kasong@redhat.com>
Cc: Kazuhito Hagio <k-hagio@ab.jp.nec.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Len Brown <len.brown@intel.com>
Cc: Lianbo Jiang <lijiang@redhat.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Miles Chen <miles.chen@mediatek.com>
Cc: Nadav Amit <namit@vmware.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Omar Sandoval <osandov@fb.com>
Cc: Pankaj gupta <pagupta@redhat.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Pavel Tatashin <pasha.tatashin@oracle.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Xavier Deguillard <xdeguillard@vmware.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm/page_alloc.c: memory hotplug: free pages as higher order
Arun KS [Tue, 5 Mar 2019 23:42:14 +0000 (15:42 -0800)]
mm/page_alloc.c: memory hotplug: free pages as higher order

When freeing pages are done with higher order, time spent on coalescing
pages by buddy allocator can be reduced.  With section size of 256MB,
hot add latency of a single section shows improvement from 50-60 ms to
less than 1 ms, hence improving the hot add latency by 60 times.  Modify
external providers of online callback to align with the change.

[arunks@codeaurora.org: v11]
Link: http://lkml.kernel.org/r/1547792588-18032-1-git-send-email-arunks@codeaurora.org
[akpm@linux-foundation.org: remove unused local, per Arun]
[akpm@linux-foundation.org: avoid return of void-returning __free_pages_core(), per Oscar]
[akpm@linux-foundation.org: fix it for mm-convert-totalram_pages-and-totalhigh_pages-variables-to-atomic.patch]
[arunks@codeaurora.org: v8]
Link: http://lkml.kernel.org/r/1547032395-24582-1-git-send-email-arunks@codeaurora.org
[arunks@codeaurora.org: v9]
Link: http://lkml.kernel.org/r/1547098543-26452-1-git-send-email-arunks@codeaurora.org
Link: http://lkml.kernel.org/r/1538727006-5727-1-git-send-email-arunks@codeaurora.org
Signed-off-by: Arun KS <arunks@codeaurora.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Reviewed-by: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Cc: K. Y. Srinivasan <kys@microsoft.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Mathieu Malaterre <malat@debian.org>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Souptick Joarder <jrdr.linux@gmail.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Aaron Lu <aaron.lu@intel.com>
Cc: Srivatsa Vaddagiri <vatsa@codeaurora.org>
Cc: Vinayak Menon <vinmenon@codeaurora.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm/slub.c: remove an unused addr argument
Qian Cai [Tue, 5 Mar 2019 23:42:10 +0000 (15:42 -0800)]
mm/slub.c: remove an unused addr argument

"addr" function argument is not used in alloc_consistency_checks() at
all, so remove it.

Link: http://lkml.kernel.org/r/20190211123214.35592-1-cai@lca.pw
Fixes: becfda68abca ("slub: convert SLAB_DEBUG_FREE to SLAB_CONSISTENCY_CHECKS")
Signed-off-by: Qian Cai <cai@lca.pw>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agoinclude/linux/slub_def.h: comment fixes
Tobin C. Harding [Tue, 5 Mar 2019 23:42:07 +0000 (15:42 -0800)]
include/linux/slub_def.h: comment fixes

Capitialize comment string, use C89 comment style, correct
grammar/punctuation in comments.

Link: http://lkml.kernel.org/r/20190204005713.9463-2-tobin@kernel.org
Link: http://lkml.kernel.org/r/20190204005713.9463-3-tobin@kernel.org
Link: http://lkml.kernel.org/r/20190204005713.9463-4-tobin@kernel.org
Signed-off-by: Tobin C. Harding <tobin@kernel.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: William Kucharski <william.kucharski@oracle.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm/slab.c: kmemleak no scan alien caches
Qian Cai [Tue, 5 Mar 2019 23:42:03 +0000 (15:42 -0800)]
mm/slab.c: kmemleak no scan alien caches

Kmemleak throws endless warnings during boot due to in
__alloc_alien_cache(),

    alc = kmalloc_node(memsize, gfp, node);
    init_arraycache(&alc->ac, entries, batch);
    kmemleak_no_scan(ac);

Kmemleak does not track the array cache (alc->ac) but the alien cache
(alc) instead, so let it track the latter by lifting kmemleak_no_scan()
out of init_arraycache().

There is another place that calls init_arraycache(), but
alloc_kmem_cache_cpus() uses the percpu allocation where will never be
considered as a leak.

  kmemleak: Found object by alias at 0xffff8007b9aa7e38
  CPU: 190 PID: 1 Comm: swapper/0 Not tainted 5.0.0-rc2+ #2
  Call trace:
   dump_backtrace+0x0/0x168
   show_stack+0x24/0x30
   dump_stack+0x88/0xb0
   lookup_object+0x84/0xac
   find_and_get_object+0x84/0xe4
   kmemleak_no_scan+0x74/0xf4
   setup_kmem_cache_node+0x2b4/0x35c
   __do_tune_cpucache+0x250/0x2d4
   do_tune_cpucache+0x4c/0xe4
   enable_cpucache+0xc8/0x110
   setup_cpu_cache+0x40/0x1b8
   __kmem_cache_create+0x240/0x358
   create_cache+0xc0/0x198
   kmem_cache_create_usercopy+0x158/0x20c
   kmem_cache_create+0x50/0x64
   fsnotify_init+0x58/0x6c
   do_one_initcall+0x194/0x388
   kernel_init_freeable+0x668/0x688
   kernel_init+0x18/0x124
   ret_from_fork+0x10/0x18
  kmemleak: Object 0xffff8007b9aa7e00 (size 256):
  kmemleak:   comm "swapper/0", pid 1, jiffies 4294697137
  kmemleak:   min_count = 1
  kmemleak:   count = 0
  kmemleak:   flags = 0x1
  kmemleak:   checksum = 0
  kmemleak:   backtrace:
       kmemleak_alloc+0x84/0xb8
       kmem_cache_alloc_node_trace+0x31c/0x3a0
       __kmalloc_node+0x58/0x78
       setup_kmem_cache_node+0x26c/0x35c
       __do_tune_cpucache+0x250/0x2d4
       do_tune_cpucache+0x4c/0xe4
       enable_cpucache+0xc8/0x110
       setup_cpu_cache+0x40/0x1b8
       __kmem_cache_create+0x240/0x358
       create_cache+0xc0/0x198
       kmem_cache_create_usercopy+0x158/0x20c
       kmem_cache_create+0x50/0x64
       fsnotify_init+0x58/0x6c
       do_one_initcall+0x194/0x388
       kernel_init_freeable+0x668/0x688
       kernel_init+0x18/0x124
  kmemleak: Not scanning unknown object at 0xffff8007b9aa7e38
  CPU: 190 PID: 1 Comm: swapper/0 Not tainted 5.0.0-rc2+ #2
  Call trace:
   dump_backtrace+0x0/0x168
   show_stack+0x24/0x30
   dump_stack+0x88/0xb0
   kmemleak_no_scan+0x90/0xf4
   setup_kmem_cache_node+0x2b4/0x35c
   __do_tune_cpucache+0x250/0x2d4
   do_tune_cpucache+0x4c/0xe4
   enable_cpucache+0xc8/0x110
   setup_cpu_cache+0x40/0x1b8
   __kmem_cache_create+0x240/0x358
   create_cache+0xc0/0x198
   kmem_cache_create_usercopy+0x158/0x20c
   kmem_cache_create+0x50/0x64
   fsnotify_init+0x58/0x6c
   do_one_initcall+0x194/0x388
   kernel_init_freeable+0x668/0x688
   kernel_init+0x18/0x124
   ret_from_fork+0x10/0x18

Link: http://lkml.kernel.org/r/20190129184518.39808-1-cai@lca.pw
Fixes: 1fe00d50a9e8 ("slab: factor out initialization of array cache")
Signed-off-by: Qian Cai <cai@lca.pw>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm/slub.c: freelist is ensured to be NULL when new_slab() fails
Peng Wang [Tue, 5 Mar 2019 23:42:00 +0000 (15:42 -0800)]
mm/slub.c: freelist is ensured to be NULL when new_slab() fails

new_slab_objects() will return immediately if freelist is not NULL.

         if (freelist)
                 return freelist;

One more assignment operation could be avoided.

Link: http://lkml.kernel.org/r/20181229062512.30469-1-rocking@whu.edu.cn
Signed-off-by: Peng Wang <rocking@whu.edu.cn>
Reviewed-by: Pekka Enberg <penberg@kernel.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agofs/file.c: initialize init_files.resize_wait
Shuriyc Chu [Tue, 5 Mar 2019 23:41:56 +0000 (15:41 -0800)]
fs/file.c: initialize init_files.resize_wait

(Taken from https://bugzilla.kernel.org/show_bug.cgi?id=200647)

'get_unused_fd_flags' in kthread cause kernel crash.  It works fine on
4.1, but causes crash after get 64 fds.  It also cause crash on
ubuntu1404/1604/1804, centos7.5, and the crash messages are almost the
same.

The crash message on centos7.5 shows below:

  start fd 61
  start fd 62
  start fd 63
  BUG: unable to handle kernel NULL pointer dereference at           (null)
  IP: __wake_up_common+0x2e/0x90
  PGD 0
  Oops: 0000 [#1] SMP
  Modules linked in: test(OE) xt_CHECKSUM iptable_mangle ipt_MASQUERADE nf_nat_masquerade_ipv4 iptable_nat nf_nat_ipv4 nf_nat nf_conntrack_ipv4 nf_defrag_ipv4 xt_conntrack nf_conntrack ipt_REJECT nf_reject_ipv4 tun bridge stp llc ebtable_filter ebtables ip6table_filter ip6_tables iptable_filter devlink sunrpc kvm_intel kvm irqbypass crc32_pclmul ghash_clmulni_intel aesni_intel lrw gf128mul glue_helper ablk_helper cryptd sg ppdev pcspkr virtio_balloon parport_pc parport i2c_piix4 joydev ip_tables xfs libcrc32c sr_mod cdrom sd_mod crc_t10dif crct10dif_generic ata_generic pata_acpi virtio_scsi virtio_console virtio_net cirrus drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops ttm crct10dif_pclmul crct10dif_common crc32c_intel drm ata_piix serio_raw libata virtio_pci virtio_ring i2c_core
   virtio floppy dm_mirror dm_region_hash dm_log dm_mod
  CPU: 2 PID: 1820 Comm: test_fd Kdump: loaded Tainted: G           OE  ------------   3.10.0-862.3.3.el7.x86_64 #1
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.10.2-0-g5f4c7b1-prebuilt.qemu-project.org 04/01/2014
  task: ffff8e92b9431fa0 ti: ffff8e94247a0000 task.ti: ffff8e94247a0000
  RIP: 0010:__wake_up_common+0x2e/0x90
  RSP: 0018:ffff8e94247a2d18  EFLAGS: 00010086
  RAX: 0000000000000000 RBX: ffffffff9d09daa0 RCX: 0000000000000000
  RDX: 0000000000000000 RSI: 0000000000000003 RDI: ffffffff9d09daa0
  RBP: ffff8e94247a2d50 R08: 0000000000000000 R09: ffff8e92b95dfda8
  R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff9d09daa8
  R13: 0000000000000003 R14: 0000000000000000 R15: 0000000000000003
  FS:  0000000000000000(0000) GS:ffff8e9434e80000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 0000000000000000 CR3: 000000017c686000 CR4: 00000000000207e0
  Call Trace:
    __wake_up+0x39/0x50
    expand_files+0x131/0x250
    __alloc_fd+0x47/0x170
    get_unused_fd_flags+0x30/0x40
    test_fd+0x12a/0x1c0 [test]
    kthread+0xd1/0xe0
    ret_from_fork_nospec_begin+0x21/0x21
  Code: 66 90 55 48 89 e5 41 57 41 89 f7 41 56 41 89 ce 41 55 41 54 49 89 fc 49 83 c4 08 53 48 83 ec 10 48 8b 47 08 89 55 cc 4c 89 45 d0 <48> 8b 08 49 39 c4 48 8d 78 e8 4c 8d 69 e8 75 08 eb 3b 4c 89 ef
  RIP   __wake_up_common+0x2e/0x90
   RSP <ffff8e94247a2d18>
  CR2: 0000000000000000

This issue exists since CentOS 7.5 3.10.0-862 and CentOS 7.4
(3.10.0-693.21.1 ) is ok.  Root cause: the item 'resize_wait' is not
initialized before being used.

Reported-by: Richard Zhang <zhang.zijian@h3c.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agofs/inode.c: inode_set_flags(): replace opencoded set_mask_bits()
Vineet Gupta [Tue, 5 Mar 2019 23:41:52 +0000 (15:41 -0800)]
fs/inode.c: inode_set_flags(): replace opencoded set_mask_bits()

It seems that commits 5f16f3225b0624 and 00a1a053ebe5, both with same
commitlog ("ext4: atomically set inode->i_flags in ext4_set_inode_flags()")
introduced the set_mask_bits API, but somehow missed not using it in ext4
in the end.

Also, set_mask_bits() is used in fs quite a bit and we can possibly come
up with a generic llsc based implementation (w/o the cmpxchg loop)

Link: http://lkml.kernel.org/r/1548275584-18096-3-git-send-email-vgupta@synopsys.com
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Reviewed-by: Anthony Yznaga <anthony.yznaga@oracle.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Miklos Szeredi <mszeredi@redhat.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agoocfs2: Use zero-sized array and struct_size() in kzalloc()
Gustavo A. R. Silva [Tue, 5 Mar 2019 23:41:48 +0000 (15:41 -0800)]
ocfs2: Use zero-sized array and struct_size() in kzalloc()

Update the code to use a zero-sized array instead of a pointer in
structure ocfs2_slot_info and use struct_size() in kzalloc().

Notice that one of the more common cases of allocation size calculations
is finding the size of a structure that has a zero-sized array at the
end, along with memory for some number of elements for that array.  For
example:

  struct foo {
      int stuff;
      void *entry[];
  };

  instance = kzalloc(sizeof(struct foo) + sizeof(void *) * count, GFP_KERNEL);

Instead of leaving these open-coded and prone to type mistakes, we can
now use the new struct_size() helper:

  instance = kzalloc(struct_size(instance, entry, count), GFP_KERNEL);

This code was detected with the help of Coccinelle.

Link: http://lkml.kernel.org/r/20190108191903.GA22056@embeddedor
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Mark Fasheh <mfasheh@versity.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Joseph Qi <joseph.qi@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agoocfs2: fix the application IO timeout when fstrim is running
Gang He [Tue, 5 Mar 2019 23:41:45 +0000 (15:41 -0800)]
ocfs2: fix the application IO timeout when fstrim is running

The user reported this problem, the upper application IO was timeout
when fstrim was running on this ocfs2 partition.  the application
monitoring resource agent considered that this application did not work,
then this node was fenced by the cluster brain (e.g.  pacemaker).

The root cause is that fstrim thread always holds main_bm meta-file
related locks until all the cluster groups are trimmed.  This patch will
make fstrim thread release main_bm meta-file related locks when each
cluster group is trimmed, this will let the current application IO has a
chance to claim the clusters from main_bm meta-file.

Link: http://lkml.kernel.org/r/20190111090014.31645-1-ghe@suse.com
Signed-off-by: Gang He <ghe@suse.com>
Reviewed-by: Changwei Ge <ge.changwei@h3c.com>
Cc: Mark Fasheh <mfasheh@versity.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Joseph Qi <joseph.qi@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agoocfs2: fix a panic problem caused by o2cb_ctl
Jia Guo [Tue, 5 Mar 2019 23:41:41 +0000 (15:41 -0800)]
ocfs2: fix a panic problem caused by o2cb_ctl

In the process of creating a node, it will cause NULL pointer
dereference in kernel if o2cb_ctl failed in the interval (mkdir,
o2cb_set_node_attribute(node_num)] in function o2cb_add_node.

The node num is initialized to 0 in function o2nm_node_group_make_item,
o2nm_node_group_drop_item will mistake the node number 0 for a valid
node number when we delete the node before the node number is set
correctly.  If the local node number of the current host happens to be
0, cluster->cl_local_node will be set to O2NM_INVALID_NODE_NUM while
o2hb_thread still running.  The panic stack is generated as follows:

  o2hb_thread
      \-o2hb_do_disk_heartbeat
          \-o2hb_check_own_slot
              |-slot = &reg->hr_slots[o2nm_this_node()];
              //o2nm_this_node() return O2NM_INVALID_NODE_NUM

We need to check whether the node number is set when we delete the node.

Link: http://lkml.kernel.org/r/133d8045-72cc-863e-8eae-5013f9f6bc51@huawei.com
Signed-off-by: Jia Guo <guojia12@huawei.com>
Reviewed-by: Joseph Qi <jiangqi903@gmail.com>
Acked-by: Jun Piao <piaojun@huawei.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <ge.changwei@h3c.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agosh: remove nargs from __SYSCALL
Firoz Khan [Tue, 5 Mar 2019 23:41:37 +0000 (15:41 -0800)]
sh: remove nargs from __SYSCALL

The __SYSCALL macro's arguments are system call number, system call
entry name and number of arguments for the system call.

Argument- nargs in __SYSCALL(nr, entry, nargs) is neither calculated nor
used anywhere.  So it would be better to keep the implementation as
__SYSCALL(nr, entry).  This unifies the implementation with some other
architectures too.

Link: http://lkml.kernel.org/r/1546443445-21075-2-git-send-email-firoz.khan@linaro.org
Signed-off-by: Firoz Khan <firoz.khan@linaro.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Cc: Simon Horman <horms+renesas@verge.net.au>
Cc: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agoscripts/decode_stacktrace.sh: handle RIP address with segment
Konstantin Khlebnikov [Tue, 5 Mar 2019 23:41:34 +0000 (15:41 -0800)]
scripts/decode_stacktrace.sh: handle RIP address with segment

decode line:

  RIP: 0010:khugepaged+0x2a2/0x2280

into

  RIP: 0010:khugepaged (mm/khugepaged.c:1885)

Link: http://lkml.kernel.org/r/154660071227.52726.15645307951282727605.stgit@buzz
Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agokasan: fix coccinelle warnings in kasan_p*_table
Andrey Konovalov [Tue, 5 Mar 2019 23:41:31 +0000 (15:41 -0800)]
kasan: fix coccinelle warnings in kasan_p*_table

kasan_p4d_table(), kasan_pmd_table() and kasan_pud_table() are declared
as returning bool, but return 0 instead of false, which produces a
coccinelle warning.  Fix it.

Link: http://lkml.kernel.org/r/1fa6fadf644859e8a6a8ecce258444b49be8c7ee.1551716733.git.andreyknvl@google.com
Fixes: 0207df4fa1a8 ("kernel/memremap, kasan: make ZONE_DEVICE with work with KASAN")
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reported-by: kbuild test robot <lkp@intel.com>
Acked-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agokasan: fix kasan_check_read/write definitions
Arnd Bergmann [Tue, 5 Mar 2019 23:41:27 +0000 (15:41 -0800)]
kasan: fix kasan_check_read/write definitions

Building little-endian allmodconfig kernels on arm64 started failing
with the generated atomic.h implementation, since we now try to call
kasan helpers from the EFI stub:

  aarch64-linux-gnu-ld: drivers/firmware/efi/libstub/arm-stub.stub.o: in function `atomic_set':
  include/generated/atomic-instrumented.h:44: undefined reference to `__efistub_kasan_check_write'

I suspect that we get similar problems in other files that explicitly
disable KASAN for some reason but call atomic_t based helper functions.

We can fix this by checking the predefined __SANITIZE_ADDRESS__ macro
that the compiler sets instead of checking CONFIG_KASAN, but this in
turn requires a small hack in mm/kasan/common.c so we do see the extern
declaration there instead of the inline function.

Link: http://lkml.kernel.org/r/20181211133453.2835077-1-arnd@arndb.de
Fixes: b1864b828644 ("locking/atomics: build atomic headers as required")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reported-by: Anders Roxell <anders.roxell@linaro.org>
Acked-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>,
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agopage_poison: play nicely with KASAN
Qian Cai [Tue, 5 Mar 2019 23:41:24 +0000 (15:41 -0800)]
page_poison: play nicely with KASAN

KASAN does not play well with the page poisoning (CONFIG_PAGE_POISONING).
It triggers false positives in the allocation path:

  BUG: KASAN: use-after-free in memchr_inv+0x2ea/0x330
  Read of size 8 at addr ffff88881f800000 by task swapper/0
  CPU: 0 PID: 0 Comm: swapper Not tainted 5.0.0-rc1+ #54
  Call Trace:
   dump_stack+0xe0/0x19a
   print_address_description.cold.2+0x9/0x28b
   kasan_report.cold.3+0x7a/0xb5
   __asan_report_load8_noabort+0x19/0x20
   memchr_inv+0x2ea/0x330
   kernel_poison_pages+0x103/0x3d5
   get_page_from_freelist+0x15e7/0x4d90

because KASAN has not yet unpoisoned the shadow page for allocation
before it checks memchr_inv() but only found a stale poison pattern.

Also, false positives in free path,

  BUG: KASAN: slab-out-of-bounds in kernel_poison_pages+0x29e/0x3d5
  Write of size 4096 at addr ffff8888112cc000 by task swapper/0/1
  CPU: 5 PID: 1 Comm: swapper/0 Not tainted 5.0.0-rc1+ #55
  Call Trace:
   dump_stack+0xe0/0x19a
   print_address_description.cold.2+0x9/0x28b
   kasan_report.cold.3+0x7a/0xb5
   check_memory_region+0x22d/0x250
   memset+0x28/0x40
   kernel_poison_pages+0x29e/0x3d5
   __free_pages_ok+0x75f/0x13e0

due to KASAN adds poisoned redzones around slab objects, but the page
poisoning needs to poison the whole page.

Link: http://lkml.kernel.org/r/20190114233405.67843-1-cai@lca.pw
Signed-off-by: Qian Cai <cai@lca.pw>
Acked-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agokasan: remove use after scope bugs detection.
Andrey Ryabinin [Tue, 5 Mar 2019 23:41:20 +0000 (15:41 -0800)]
kasan: remove use after scope bugs detection.

Use after scope bugs detector seems to be almost entirely useless for
the linux kernel.  It exists over two years, but I've seen only one
valid bug so far [1].  And the bug was fixed before it has been
reported.  There were some other use-after-scope reports, but they were
false-positives due to different reasons like incompatibility with
structleak plugin.

This feature significantly increases stack usage, especially with GCC <
9 version, and causes a 32K stack overflow.  It probably adds
performance penalty too.

Given all that, let's remove use-after-scope detector entirely.

While preparing this patch I've noticed that we mistakenly enable
use-after-scope detection for clang compiler regardless of
CONFIG_KASAN_EXTRA setting.  This is also fixed now.

[1] http://lkml.kernel.org/r/<20171129052106.rhgbjhhis53hkgfn@wfg-t540p.sh.intel.com>

Link: http://lkml.kernel.org/r/20190111185842.13978-1-aryabinin@virtuozzo.com
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Acked-by: Will Deacon <will.deacon@arm.com> [arm64]
Cc: Qian Cai <cai@lca.pw>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agomm: hwpoison: fix thp split handing in soft_offline_in_use_page()
zhongjiang [Tue, 5 Mar 2019 23:41:16 +0000 (15:41 -0800)]
mm: hwpoison: fix thp split handing in soft_offline_in_use_page()

When soft_offline_in_use_page() runs on a thp tail page after pmd is
split, we trigger the following VM_BUG_ON_PAGE():

  Memory failure: 0x3755ff: non anonymous thp
  __get_any_page: 0x3755ff: unknown zero refcount page type 2fffff80000000
  Soft offlining pfn 0x34d805 at process virtual address 0x20fff000
  page:ffffea000d360140 count:0 mapcount:0 mapping:0000000000000000 index:0x1
  flags: 0x2fffff80000000()
  raw: 002fffff80000000 ffffea000d360108 ffffea000d360188 0000000000000000
  raw: 0000000000000001 0000000000000000 00000000ffffffff 0000000000000000
  page dumped because: VM_BUG_ON_PAGE(page_ref_count(page) == 0)
  ------------[ cut here ]------------
  kernel BUG at ./include/linux/mm.h:519!

soft_offline_in_use_page() passed refcount and page lock from tail page
to head page, which is not needed because we can pass any subpage to
split_huge_page().

Naoya had fixed a similar issue in c3901e722b29 ("mm: hwpoison: fix thp
split handling in memory_failure()").  But he missed fixing soft
offline.

Link: http://lkml.kernel.org/r/1551452476-24000-1-git-send-email-zhongjiang@huawei.com
Fixes: 61f5d698cc97 ("mm: re-enable THP")
Signed-off-by: zhongjiang <zhongjiang@huawei.com>
Acked-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: <stable@vger.kernel.org> [4.5+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 months agoMerge tag 'mips_5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux
Linus Torvalds [Tue, 5 Mar 2019 19:28:25 +0000 (11:28 -0800)]
Merge tag 'mips_5.1' of git://git./linux/kernel/git/mips/linux

Pull MIPS updates from Paul Burton:

 - Support for the MIPSr6 MemoryMapID register & Global INValidate TLB
   (GINVT) instructions, allowing for more efficient TLB maintenance
   when running on a CPU such as the I6500 that supports these.

 - Enable huge page support for MIPS64r6.

 - Optimize post-DMA cache sync by removing that code entirely for
   kernel configurations in which we know it won't be needed.

 - The number of pages allocated for interrupt stacks is now calculated
   correctly, where before we would wastefully allocate too much memory
   in some configurations.

 - The ath79 platform migrates to devicetree.

 - The bcm47xx platform sees fixes for the Buffalo WHR-G54S board.

 - The ingenic/jz4740 platform gains support for appended devicetrees.

 - The cavium_octeon, lantiq, loongson32 & sgi-ip27 platforms all see
   cleanups as do various pieces of core architecture code.

* tag 'mips_5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux: (66 commits)
  MIPS: lantiq: Remove separate GPHY Firmware loader
  MIPS: ingenic: Add support for appended devicetree
  MIPS: SGI-IP27: rework HUB interrupts
  MIPS: SGI-IP27: do boot CPU init later
  MIPS: SGI-IP27: do xtalk scanning later
  MIPS: SGI-IP27: use pr_info/pr_emerg and pr_cont to fix output
  MIPS: SGI-IP27: clean up bridge access and header files
  MIPS: SGI-IP27: get rid of volatile and hubreg_t
  MIPS: irq: Allocate accurate order pages for irq stack
  MIPS: dma-noncoherent: Remove bogus condition in dma_sync_phys()
  MIPS: eBPF: Remove REG_32BIT_ZERO_EX
  MIPS: eBPF: Always return sign extended 32b values
  MIPS: CM: Fix indentation
  MIPS: BCM47XX: Fix/improve Buffalo WHR-G54S support
  MIPS: OCTEON: program rx/tx-delay always from DT
  MIPS: OCTEON: delete board-specific link status
  MIPS: OCTEON: don't lie about interface type of CN3005 board
  MIPS: OCTEON: warn if deprecated link status is being used
  MIPS: OCTEON: add fixed-link nodes to in-kernel device tree
  MIPS: Delete unused flush_cache_sigtramp()
  ...

12 months agoMerge branch 'parisc-5.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller...
Linus Torvalds [Tue, 5 Mar 2019 19:17:23 +0000 (11:17 -0800)]
Merge branch 'parisc-5.1-1' of git://git./linux/kernel/git/deller/parisc-linux

Pull parisc updates from Helge Deller:
 "The most important changes in this patch set are:

   - DMA-related cleanups for parisc with the aim to move anything not
     required by drivers out of <asm/dma-mapping.h>, by Christoph
     Hellwig

   - Switch to memblock_alloc(), by Mike Rapoport

   - Makefile cleanups by Masahiro Yamada

   - Switch to bust_spinlocks(), by Sergey Senozhatsky

   - Improved initial SMP affinity selection for IRQs

   - Added IPI- and rescheduling interrupts in /proc/interrupts output"

* 'parisc-5.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux: (21 commits)
  parisc: use memblock_alloc() instead of custom get_memblock()
  parisc: Add constants for various PDC firmware calls
  parisc: Add constant for PDC_PAT_COMPLEX firmware call
  parisc: Show machine product number during boot
  parisc: Add constants for PDC_RELOCATE PDC call
  parisc: Add PDC_CRASH_PREP PDC function number
  parisc: Use F_EXTEND() macro in iosapic code
  parisc: remove the HBA_DATA macro
  parisc/lba_pci: use container_of in LBA_DEV
  parisc/dino: use container_of in DINO_DEV
  parisc: properly type the return value of parisc_walk_tree
  parisc: properly type the iommu field in struct pci_hba_data
  parisc: turn GET_IOC into an inline function
  parisc: move internal implementation details out of <asm/dma-mapping.h>
  parisc: don't include <asm/cacheflush.h> in <asm/dma-mapping.h>
  parisc: remove meaningless ccflags-y in arch/parisc/boot/Makefile
  parisc: replace oops_in_progress manipulation with bust_spinlocks()
  parisc: Improve initial IRQ to CPU assignment
  parisc: Count IPI function call interrupts
  parisc: Show rescheduling interrupts on SMP machines only
  ...