sfrench/cifs-2.6.git
6 years agomm: rename global_page_state to global_zone_page_state
Michal Hocko [Wed, 6 Sep 2017 23:23:36 +0000 (16:23 -0700)]
mm: rename global_page_state to global_zone_page_state

global_page_state is error prone as a recent bug report pointed out [1].
It only returns proper values for zone based counters as the enum it
gets suggests.  We already have global_node_page_state so let's rename
global_page_state to global_zone_page_state to be more explicit here.
All existing users seems to be correct:

$ git grep "global_page_state(NR_" | sed 's@.*(\(NR_[A-Z_]*\)).*@\1@' | sort | uniq -c
      2 NR_BOUNCE
      2 NR_FREE_CMA_PAGES
     11 NR_FREE_PAGES
      1 NR_KERNEL_STACK_KB
      1 NR_MLOCK
      2 NR_PAGETABLE

This patch shouldn't introduce any functional change.

[1] http://lkml.kernel.org/r/201707260628.v6Q6SmaS030814@www262.sakura.ne.jp

Link: http://lkml.kernel.org/r/20170801134256.5400-2-hannes@cmpxchg.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Cc: Josef Bacik <josef@toxicpanda.com>
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>
6 years agomm: shm: use new hugetlb size encoding definitions
Mike Kravetz [Wed, 6 Sep 2017 23:23:33 +0000 (16:23 -0700)]
mm: shm: use new hugetlb size encoding definitions

Use the common definitions from hugetlb_encode.h header file for
encoding hugetlb size definitions in shmget system call flags.

In addition, move these definitions from the internal (kernel) to user
(uapi) header file.

Link: http://lkml.kernel.org/r/1501527386-10736-4-git-send-email-mike.kravetz@oracle.com
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Suggested-by: Matthew Wilcox <willy@infradead.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agomm: arch: consolidate mmap hugetlb size encodings
Mike Kravetz [Wed, 6 Sep 2017 23:23:29 +0000 (16:23 -0700)]
mm: arch: consolidate mmap hugetlb size encodings

A non-default huge page size can be encoded in the flags argument of the
mmap system call.  The definitions for these encodings are in arch
specific header files.  However, all architectures use the same values.

Consolidate all the definitions in the primary user header file
(uapi/linux/mman.h).  Include definitions for all known huge page sizes.
Use the generic encoding definitions in hugetlb_encode.h as the basis
for these definitions.

Link: http://lkml.kernel.org/r/1501527386-10736-3-git-send-email-mike.kravetz@oracle.com
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agomm: hugetlb: define system call hugetlb size encodings in single file
Mike Kravetz [Wed, 6 Sep 2017 23:23:25 +0000 (16:23 -0700)]
mm: hugetlb: define system call hugetlb size encodings in single file

Patch series "Consolidate system call hugetlb page size encodings".

These patches are the result of discussions in
https://lkml.org/lkml/2017/3/8/548.  The following changes are made in the
patch set:

1) Put all the log2 encoded huge page size definitions in a common
   header file.  The idea is have a set of definitions that can be use as
   the basis for system call specific definitions such as MAP_HUGE_* and
   SHM_HUGE_*.

2) Remove MAP_HUGE_* definitions in arch specific files.  All these
   definitions are the same.  Consolidate all definitions in the primary
   user header file (uapi/linux/mman.h).

3) Remove SHM_HUGE_* definitions intended for user space from kernel
   header file, and add to user (uapi/linux/shm.h) header file.  Add
   definitions for all known huge page size encodings as in mmap.

This patch (of 3):

If hugetlb pages are requested in mmap or shmget system calls, a huge
page size other than default can be requested.  This is accomplished by
encoding the log2 of the huge page size in the upper bits of the flag
argument.  asm-generic and arch specific headers all define the same
values for these encodings.

Put common definitions in a single header file.  The primary uapi header
files for mmap and shm will use these definitions as a basis for
definitions specific to those system calls.

Link: http://lkml.kernel.org/r/1501527386-10736-2-git-send-email-mike.kravetz@oracle.com
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agoinclude/linux/fs.h: remove unneeded forward definition of mm_struct
Jeff Layton [Wed, 6 Sep 2017 23:23:22 +0000 (16:23 -0700)]
include/linux/fs.h: remove unneeded forward definition of mm_struct

Link: http://lkml.kernel.org/r/20170525102927.6163-1-jlayton@redhat.com
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agofs/sync.c: remove unnecessary NULL f_mapping check in sync_file_range
Jeff Layton [Wed, 6 Sep 2017 23:23:19 +0000 (16:23 -0700)]
fs/sync.c: remove unnecessary NULL f_mapping check in sync_file_range

fsync codepath assumes that f_mapping can never be NULL, but
sync_file_range has a check for that.

Remove the one from sync_file_range as I don't see how you'd ever get a
NULL pointer in here.

Link: http://lkml.kernel.org/r/20170525110509.9434-1-jlayton@redhat.com
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agouserfaultfd: selftest: enable testing of UFFDIO_ZEROPAGE for shmem
Mike Rapoport [Wed, 6 Sep 2017 23:23:16 +0000 (16:23 -0700)]
userfaultfd: selftest: enable testing of UFFDIO_ZEROPAGE for shmem

Link: http://lkml.kernel.org/r/1497939652-16528-8-git-send-email-rppt@linux.vnet.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Pavel Emelyanov <xemul@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agouserfaultfd: report UFFDIO_ZEROPAGE as available for shmem VMAs
Mike Rapoport [Wed, 6 Sep 2017 23:23:12 +0000 (16:23 -0700)]
userfaultfd: report UFFDIO_ZEROPAGE as available for shmem VMAs

Now when shmem VMAs can be filled with zero page via userfaultfd we can
report that UFFDIO_ZEROPAGE is available for those VMAs

Link: http://lkml.kernel.org/r/1497939652-16528-7-git-send-email-rppt@linux.vnet.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Pavel Emelyanov <xemul@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agouserfaultfd: shmem: wire up shmem_mfill_zeropage_pte
Mike Rapoport [Wed, 6 Sep 2017 23:23:09 +0000 (16:23 -0700)]
userfaultfd: shmem: wire up shmem_mfill_zeropage_pte

For shmem VMAs we can use shmem_mfill_zeropage_pte for UFFDIO_ZEROPAGE

Link: http://lkml.kernel.org/r/1497939652-16528-6-git-send-email-rppt@linux.vnet.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Pavel Emelyanov <xemul@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agouserfaultfd: mcopy_atomic: introduce mfill_atomic_pte helper
Mike Rapoport [Wed, 6 Sep 2017 23:23:06 +0000 (16:23 -0700)]
userfaultfd: mcopy_atomic: introduce mfill_atomic_pte helper

Shuffle the code a bit to improve readability.

Link: http://lkml.kernel.org/r/1497939652-16528-5-git-send-email-rppt@linux.vnet.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Pavel Emelyanov <xemul@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agouserfaultfd: shmem: add shmem_mfill_zeropage_pte for userfaultfd support
Mike Rapoport [Wed, 6 Sep 2017 23:23:02 +0000 (16:23 -0700)]
userfaultfd: shmem: add shmem_mfill_zeropage_pte for userfaultfd support

shmem_mfill_zeropage_pte is the low level routine that implements the
userfaultfd UFFDIO_ZEROPAGE command.  Since for shmem mappings zero
pages are always allocated and accounted, the new method is a slight
extension of the existing shmem_mcopy_atomic_pte.

Link: http://lkml.kernel.org/r/1497939652-16528-4-git-send-email-rppt@linux.vnet.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Pavel Emelyanov <xemul@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agoshmem: introduce shmem_inode_acct_block
Mike Rapoport [Wed, 6 Sep 2017 23:22:59 +0000 (16:22 -0700)]
shmem: introduce shmem_inode_acct_block

The shmem_acct_block and the update of used_blocks are following one
another in all the places they are used.  Combine these two into a
helper function.

Link: http://lkml.kernel.org/r/1497939652-16528-3-git-send-email-rppt@linux.vnet.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Pavel Emelyanov <xemul@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agoshmem: shmem_charge: verify max_block is not exceeded before inode update
Mike Rapoport [Wed, 6 Sep 2017 23:22:56 +0000 (16:22 -0700)]
shmem: shmem_charge: verify max_block is not exceeded before inode update

Patch series "userfaultfd: enable zeropage support for shmem".

These patches enable support for UFFDIO_ZEROPAGE for shared memory.

The first two patches are not strictly related to userfaultfd, they are
just minor refactoring to reduce amount of code duplication.

This patch (of 7):

Currently we update inode and shmem_inode_info before verifying that
used_blocks will not exceed max_blocks.  In case it will, we undo the
update.  Let's switch the order and move the verification of the blocks
count before the inode and shmem_inode_info update.

Link: http://lkml.kernel.org/r/1497939652-16528-2-git-send-email-rppt@linux.vnet.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Pavel Emelyanov <xemul@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agomm, THP, swap: add THP swapping out fallback counting
Huang Ying [Wed, 6 Sep 2017 23:22:52 +0000 (16:22 -0700)]
mm, THP, swap: add THP swapping out fallback counting

When swapping out THP (Transparent Huge Page), instead of swapping out
the THP as a whole, sometimes we have to fallback to split the THP into
normal pages before swapping, because no free swap clusters are
available, or cgroup limit is exceeded, etc.  To count the number of the
fallback, a new VM event THP_SWPOUT_FALLBACK is added, and counted when
we fallback to split the THP.

Link: http://lkml.kernel.org/r/20170724051840.2309-13-ying.huang@intel.com
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Shaohua Li <shli@kernel.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Ross Zwisler <ross.zwisler@intel.com> [for brd.c, zram_drv.c, pmem.c]
Cc: Vishal L Verma <vishal.l.verma@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agomm, THP, swap: delay splitting THP after swapped out
Huang Ying [Wed, 6 Sep 2017 23:22:49 +0000 (16:22 -0700)]
mm, THP, swap: delay splitting THP after swapped out

In this patch, splitting transparent huge page (THP) during swapping out
is delayed from after adding the THP into the swap cache to after
swapping out finishes.  After the patch, more operations for the
anonymous THP reclaiming, such as writing the THP to the swap device,
removing the THP from the swap cache could be batched.  So that the
performance of anonymous THP swapping out could be improved.

This is the second step for the THP swap support.  The plan is to delay
splitting the THP step by step and avoid splitting the THP finally.

With the patchset, the swap out throughput improves 42% (from about
5.81GB/s to about 8.25GB/s) in the vm-scalability swap-w-seq test case
with 16 processes.  At the same time, the IPI (reflect TLB flushing)
reduced about 78.9%.  The test is done on a Xeon E5 v3 system.  The swap
device used is a RAM simulated PMEM (persistent memory) device.  To test
the sequential swapping out, the test case creates 8 processes, which
sequentially allocate and write to the anonymous pages until the RAM and
part of the swap device is used up.

Link: http://lkml.kernel.org/r/20170724051840.2309-12-ying.huang@intel.com
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Shaohua Li <shli@kernel.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Ross Zwisler <ross.zwisler@intel.com> [for brd.c, zram_drv.c, pmem.c]
Cc: Vishal L Verma <vishal.l.verma@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agomemcg, THP, swap: make mem_cgroup_swapout() support THP
Huang Ying [Wed, 6 Sep 2017 23:22:45 +0000 (16:22 -0700)]
memcg, THP, swap: make mem_cgroup_swapout() support THP

This patch makes mem_cgroup_swapout() works for the transparent huge
page (THP).  Which will move the memory cgroup charge from memory to
swap for a THP.

This will be used for the THP swap support.  Where a THP may be swapped
out as a whole to a set of (HPAGE_PMD_NR) continuous swap slots on the
swap device.

Link: http://lkml.kernel.org/r/20170724051840.2309-11-ying.huang@intel.com
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Rik van Riel <riel@redhat.com>
Cc: Ross Zwisler <ross.zwisler@intel.com> [for brd.c, zram_drv.c, pmem.c]
Cc: Shaohua Li <shli@kernel.org>
Cc: Vishal L Verma <vishal.l.verma@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agomemcg, THP, swap: avoid to duplicated charge THP in swap cache
Huang Ying [Wed, 6 Sep 2017 23:22:41 +0000 (16:22 -0700)]
memcg, THP, swap: avoid to duplicated charge THP in swap cache

For a THP (Transparent Huge Page), tail_page->mem_cgroup is NULL.  So to
check whether the page is charged already, we need to check the head
page.  This is not an issue before because it is impossible for a THP to
be in the swap cache before.  But after we add delaying splitting THP
after swapped out support, it is possible now.

Link: http://lkml.kernel.org/r/20170724051840.2309-10-ying.huang@intel.com
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Rik van Riel <riel@redhat.com>
Cc: Ross Zwisler <ross.zwisler@intel.com> [for brd.c, zram_drv.c, pmem.c]
Cc: Shaohua Li <shli@kernel.org>
Cc: Vishal L Verma <vishal.l.verma@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agomemcg, THP, swap: support move mem cgroup charge for THP swapped out
Huang Ying [Wed, 6 Sep 2017 23:22:37 +0000 (16:22 -0700)]
memcg, THP, swap: support move mem cgroup charge for THP swapped out

PTE mapped THP (Transparent Huge Page) will be ignored when moving
memory cgroup charge.  But for THP which is in the swap cache, the
memory cgroup charge for the swap of a tail-page may be moved in current
implementation.  That isn't correct, because the swap charge for all
sub-pages of a THP should be moved together.  Following the processing
of the PTE mapped THP, the mem cgroup charge moving for the swap entry
for a tail-page of a THP is ignored too.

Link: http://lkml.kernel.org/r/20170724051840.2309-9-ying.huang@intel.com
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Rik van Riel <riel@redhat.com>
Cc: Ross Zwisler <ross.zwisler@intel.com> [for brd.c, zram_drv.c, pmem.c]
Cc: Shaohua Li <shli@kernel.org>
Cc: Vishal L Verma <vishal.l.verma@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agomm, THP, swap: support splitting THP for THP swap out
Huang Ying [Wed, 6 Sep 2017 23:22:34 +0000 (16:22 -0700)]
mm, THP, swap: support splitting THP for THP swap out

After adding swapping out support for THP (Transparent Huge Page), it is
possible that a THP in swap cache (partly swapped out) need to be split.
To split such a THP, the swap cluster backing the THP need to be split
too, that is, the CLUSTER_FLAG_HUGE flag need to be cleared for the swap
cluster.  The patch implemented this.

And because the THP swap writing needs the THP keeps as huge page during
writing.  The PageWriteback flag is checked before splitting.

Link: http://lkml.kernel.org/r/20170724051840.2309-8-ying.huang@intel.com
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Shaohua Li <shli@kernel.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Ross Zwisler <ross.zwisler@intel.com> [for brd.c, zram_drv.c, pmem.c]
Cc: Vishal L Verma <vishal.l.verma@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agomm: test code to write THP to swap device as a whole
Huang Ying [Wed, 6 Sep 2017 23:22:30 +0000 (16:22 -0700)]
mm: test code to write THP to swap device as a whole

To support delay splitting THP (Transparent Huge Page) after swapped
out, we need to enhance swap writing code to support to write a THP as a
whole.  This will improve swap write IO performance.

As Ming Lei <ming.lei@redhat.com> pointed out, this should be based on
multipage bvec support, which hasn't been merged yet.  So this patch is
only for testing the functionality of the other patches in the series.
And will be reimplemented after multipage bvec support is merged.

Link: http://lkml.kernel.org/r/20170724051840.2309-7-ying.huang@intel.com
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Ross Zwisler <ross.zwisler@intel.com> [for brd.c, zram_drv.c, pmem.c]
Cc: Shaohua Li <shli@kernel.org>
Cc: Vishal L Verma <vishal.l.verma@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agoblock, THP: make block_device_operations.rw_page support THP
Huang Ying [Wed, 6 Sep 2017 23:22:27 +0000 (16:22 -0700)]
block, THP: make block_device_operations.rw_page support THP

The .rw_page in struct block_device_operations is used by the swap
subsystem to read/write the page contents from/into the corresponding
swap slot in the swap device.  To support the THP (Transparent Huge
Page) swap optimization, the .rw_page is enhanced to support to
read/write THP if possible.

Link: http://lkml.kernel.org/r/20170724051840.2309-6-ying.huang@intel.com
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Reviewed-by: Ross Zwisler <ross.zwisler@intel.com> [for brd.c, zram_drv.c, pmem.c]
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Vishal L Verma <vishal.l.verma@intel.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Shaohua Li <shli@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agomm, THP, swap: don't allocate huge cluster for file backed swap device
Huang Ying [Wed, 6 Sep 2017 23:22:23 +0000 (16:22 -0700)]
mm, THP, swap: don't allocate huge cluster for file backed swap device

It's hard to write a whole transparent huge page (THP) to a file backed
swap device during swapping out and the file backed swap device isn't
very popular.  So the huge cluster allocation for the file backed swap
device is disabled.

Link: http://lkml.kernel.org/r/20170724051840.2309-5-ying.huang@intel.com
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Shaohua Li <shli@kernel.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Ross Zwisler <ross.zwisler@intel.com> [for brd.c, zram_drv.c, pmem.c]
Cc: Vishal L Verma <vishal.l.verma@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agomm, THP, swap: make reuse_swap_page() works for THP swapped out
Huang Ying [Wed, 6 Sep 2017 23:22:19 +0000 (16:22 -0700)]
mm, THP, swap: make reuse_swap_page() works for THP swapped out

After supporting to delay THP (Transparent Huge Page) splitting after
swapped out, it is possible that some page table mappings of the THP are
turned into swap entries.  So reuse_swap_page() need to check the swap
count in addition to the map count as before.  This patch done that.

In the huge PMD write protect fault handler, in addition to the page map
count, the swap count need to be checked too, so the page lock need to
be acquired too when calling reuse_swap_page() in addition to the page
table lock.

[ying.huang@intel.com: silence a compiler warning]
Link: http://lkml.kernel.org/r/87bmnzizjy.fsf@yhuang-dev.intel.com
Link: http://lkml.kernel.org/r/20170724051840.2309-4-ying.huang@intel.com
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Shaohua Li <shli@kernel.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Ross Zwisler <ross.zwisler@intel.com> [for brd.c, zram_drv.c, pmem.c]
Cc: Vishal L Verma <vishal.l.verma@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agomm, THP, swap: support to reclaim swap space for THP swapped out
Huang Ying [Wed, 6 Sep 2017 23:22:16 +0000 (16:22 -0700)]
mm, THP, swap: support to reclaim swap space for THP swapped out

The normal swap slot reclaiming can be done when the swap count reaches
SWAP_HAS_CACHE.  But for the swap slot which is backing a THP, all swap
slots backing one THP must be reclaimed together, because the swap slot
may be used again when the THP is swapped out again later.  So the swap
slots backing one THP can be reclaimed together when the swap count for
all swap slots for the THP reached SWAP_HAS_CACHE.  In the patch, the
functions to check whether the swap count for all swap slots backing one
THP reached SWAP_HAS_CACHE are implemented and used when checking
whether a swap slot can be reclaimed.

To make it easier to determine whether a swap slot is backing a THP, a
new swap cluster flag named CLUSTER_FLAG_HUGE is added to mark a swap
cluster which is backing a THP (Transparent Huge Page).  Because THP
swap in as a whole isn't supported now.  After deleting the THP from the
swap cache (for example, swapping out finished), the CLUSTER_FLAG_HUGE
flag will be cleared.  So that, the normal pages inside THP can be
swapped in individually.

[ying.huang@intel.com: fix swap_page_trans_huge_swapped on HDD]
Link: http://lkml.kernel.org/r/874ltsm0bi.fsf@yhuang-dev.intel.com
Link: http://lkml.kernel.org/r/20170724051840.2309-3-ying.huang@intel.com
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Shaohua Li <shli@kernel.org>
Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Ross Zwisler <ross.zwisler@intel.com> [for brd.c, zram_drv.c, pmem.c]
Cc: Vishal L Verma <vishal.l.verma@intel.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agomm, THP, swap: support to clear swap cache flag for THP swapped out
Huang Ying [Wed, 6 Sep 2017 23:22:12 +0000 (16:22 -0700)]
mm, THP, swap: support to clear swap cache flag for THP swapped out

Patch series "mm, THP, swap: Delay splitting THP after swapped out", v3.

This is the second step of THP (Transparent Huge Page) swap
optimization.  In the first step, the splitting huge page is delayed
from almost the first step of swapping out to after allocating the swap
space for the THP and adding the THP into the swap cache.  In the second
step, the splitting is delayed further to after the swapping out
finished.  The plan is to delay splitting THP step by step, finally
avoid splitting THP for the THP swapping out and swap out/in the THP as
a whole.

In the patchset, more operations for the anonymous THP reclaiming, such
as TLB flushing, writing the THP to the swap device, removing the THP
from the swap cache are batched.  So that the performance of anonymous
THP swapping out are improved.

During the development, the following scenarios/code paths have been
checked,

 - swap out/in
 - swap off
 - write protect page fault
 - madvise_free
 - process exit
 - split huge page

With the patchset, the swap out throughput improves 42% (from about
5.81GB/s to about 8.25GB/s) in the vm-scalability swap-w-seq test case
with 16 processes.  At the same time, the IPI (reflect TLB flushing)
reduced about 78.9%.  The test is done on a Xeon E5 v3 system.  The swap
device used is a RAM simulated PMEM (persistent memory) device.  To test
the sequential swapping out, the test case creates 8 processes, which
sequentially allocate and write to the anonymous pages until the RAM and
part of the swap device is used up.

Below is the part of the cover letter for the first step patchset of THP
swap optimization which applies to all steps.

=========================

Recently, the performance of the storage devices improved so fast that
we cannot saturate the disk bandwidth with single logical CPU when do
page swap out even on a high-end server machine.  Because the
performance of the storage device improved faster than that of single
logical CPU.  And it seems that the trend will not change in the near
future.  On the other hand, the THP becomes more and more popular
because of increased memory size.  So it becomes necessary to optimize
THP swap performance.

The advantages of the THP swap support include:

 - Batch the swap operations for the THP to reduce TLB flushing and lock
   acquiring/releasing, including allocating/freeing the swap space,
   adding/deleting to/from the swap cache, and writing/reading the swap
   space, etc. This will help improve the performance of the THP swap.

 - The THP swap space read/write will be 2M sequential IO. It is
   particularly helpful for the swap read, which are usually 4k random
   IO. This will improve the performance of the THP swap too.

 - It will help the memory fragmentation, especially when the THP is
   heavily used by the applications. The 2M continuous pages will be
   free up after THP swapping out.

 - It will improve the THP utilization on the system with the swap
   turned on. Because the speed for khugepaged to collapse the normal
   pages into the THP is quite slow. After the THP is split during the
   swapping out, it will take quite long time for the normal pages to
   collapse back into the THP after being swapped in. The high THP
   utilization helps the efficiency of the page based memory management
   too.

There are some concerns regarding THP swap in, mainly because possible
enlarged read/write IO size (for swap in/out) may put more overhead on
the storage device.  To deal with that, the THP swap in should be turned
on only when necessary.

For example, it can be selected via "always/never/madvise" logic, to be
turned on globally, turned off globally, or turned on only for VMA with
MADV_HUGEPAGE, etc.

This patch (of 12):

Previously, swapcache_free_cluster() is used only in the error path of
shrink_page_list() to free the swap cluster just allocated if the THP
(Transparent Huge Page) is failed to be split.  In this patch, it is
enhanced to clear the swap cache flag (SWAP_HAS_CACHE) for the swap
cluster that holds the contents of THP swapped out.

This will be used in delaying splitting THP after swapping out support.
Because there is no THP swapping in as a whole support yet, after
clearing the swap cache flag, the swap cluster backing the THP swapped
out will be split.  So that the swap slots in the swap cluster can be
swapped in as normal pages later.

Link: http://lkml.kernel.org/r/20170724051840.2309-2-ying.huang@intel.com
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Shaohua Li <shli@kernel.org>
Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Ross Zwisler <ross.zwisler@intel.com> [for brd.c, zram_drv.c, pmem.c]
Cc: Vishal L Verma <vishal.l.verma@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agomm: memcontrol: use int for event/state parameter in several functions
Matthias Kaehlcke [Wed, 6 Sep 2017 23:22:09 +0000 (16:22 -0700)]
mm: memcontrol: use int for event/state parameter in several functions

Several functions use an enum type as parameter for an event/state, but
are called in some locations with an argument of a different enum type.
Adjust the interface of these functions to reality by changing the
parameter to int.

This fixes a ton of enum-conversion warnings that are generated when
building the kernel with clang.

[mka@chromium.org: also change parameter type of inc/dec/mod_memcg_page_state()]
Link: http://lkml.kernel.org/r/20170728213442.93823-1-mka@chromium.org
Link: http://lkml.kernel.org/r/20170727211004.34435-1-mka@chromium.org
Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Doug Anderson <dianders@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agomm/hugetlb.c: constify attribute_group structures
Arvind Yadav [Wed, 6 Sep 2017 23:22:06 +0000 (16:22 -0700)]
mm/hugetlb.c: constify attribute_group structures

attribute_group are not supposed to change at runtime.  All functions
working with attribute_group provided by <linux/sysfs.h> work with const
attribute_group.  So mark the non-const structs as const.

Link: http://lkml.kernel.org/r/1501157260-3922-1-git-send-email-arvind.yadav.cs@gmail.com
Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agomm/huge_memory.c: constify attribute_group structures
Arvind Yadav [Wed, 6 Sep 2017 23:22:03 +0000 (16:22 -0700)]
mm/huge_memory.c: constify attribute_group structures

attribute_group are not supposed to change at runtime.  All functions
working with attribute_group provided by <linux/sysfs.h> work with const
attribute_group.  So mark the non-const structs as const.

Link: http://lkml.kernel.org/r/1501157240-3876-1-git-send-email-arvind.yadav.cs@gmail.com
Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agomm/page_idle.c: constify attribute_group structures
Arvind Yadav [Wed, 6 Sep 2017 23:21:59 +0000 (16:21 -0700)]
mm/page_idle.c: constify attribute_group structures

attribute_group are not supposed to change at runtime.  All functions
working with attribute_group provided by <linux/sysfs.h> work with const
attribute_group.  So mark the non-const structs as const.

Link: http://lkml.kernel.org/r/1501157221-3832-1-git-send-email-arvind.yadav.cs@gmail.com
Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agomm/slub.c: constify attribute_group structures
Arvind Yadav [Wed, 6 Sep 2017 23:21:56 +0000 (16:21 -0700)]
mm/slub.c: constify attribute_group structures

attribute_group are not supposed to change at runtime.  All functions
working with attribute_group provided by <linux/sysfs.h> work with const
attribute_group.  So mark the non-const structs as const.

Link: http://lkml.kernel.org/r/1501157186-3749-1-git-send-email-arvind.yadav.cs@gmail.com
Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Acked-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agomm/ksm.c: constify attribute_group structures
Arvind Yadav [Wed, 6 Sep 2017 23:21:53 +0000 (16:21 -0700)]
mm/ksm.c: constify attribute_group structures

attribute_group are not supposed to change at runtime.  All functions
working with attribute_group provided by <linux/sysfs.h> work with const
attribute_group.  So mark the non-const structs as const.

Link: http://lkml.kernel.org/r/1501157167-3706-2-git-send-email-arvind.yadav.cs@gmail.com
Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agocgroup: revert fa06235b8eb0 ("cgroup: reset css on destruction")
Roman Gushchin [Wed, 6 Sep 2017 23:21:50 +0000 (16:21 -0700)]
cgroup: revert fa06235b8eb0 ("cgroup: reset css on destruction")

Commit fa06235b8eb0 ("cgroup: reset css on destruction") caused
css_reset callback to be called from the offlining path.  Although it
solves the problem mentioned in the commit description ("For instance,
memory cgroup needs to reset memory.low, otherwise pages charged to a
dead cgroup might never get reclaimed."), generally speaking, it's not
correct.

An offline cgroup can still be a resource domain, and we shouldn't grant
it more resources than it had before deletion.

For instance, if an offline memory cgroup has dirty pages, we should
still imply i/o limits during writeback.

The css_reset callback is designed to return the cgroup state into the
original state, that means reset all limits and counters.  It's
spomething different from the offlining, and we shouldn't use it from
the offlining path.  Instead, we should adjust necessary settings from
the per-controller css_offline callbacks (e.g.  reset memory.low).

Link: http://lkml.kernel.org/r/20170727130428.28856-2-guro@fb.com
Signed-off-by: Roman Gushchin <guro@fb.com>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Vladimir Davydov <vdavydov.dev@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>
6 years agomm, memcg: reset memory.low during memcg offlining
Roman Gushchin [Wed, 6 Sep 2017 23:21:47 +0000 (16:21 -0700)]
mm, memcg: reset memory.low during memcg offlining

A removed memory cgroup with a defined memory.low and some belonging
pagecache has very low chances to be freed.

If a cgroup has been removed, there is likely no memory pressure inside
the cgroup, and the pagecache is protected from the external pressure by
the defined low limit.  The cgroup will be freed only after the reclaim
of all belonging pages.  And it will not happen until there are any
reclaimable memory in the system.  That means, there is a good chance,
that a cold pagecache will reside in the memory for an undefined amount
of time, wasting system resources.

This problem was fixed earlier by fa06235b8eb0 ("cgroup: reset css on
destruction"), but it's not a best way to do it, as we can't really
reset all limits/counters during cgroup offlining.

Link: http://lkml.kernel.org/r/20170727130428.28856-1-guro@fb.com
Signed-off-by: Roman Gushchin <guro@fb.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agomm: remove nr_pages argument from pagevec_lookup{,_range}()
Jan Kara [Wed, 6 Sep 2017 23:21:43 +0000 (16:21 -0700)]
mm: remove nr_pages argument from pagevec_lookup{,_range}()

All users of pagevec_lookup() and pagevec_lookup_range() now pass
PAGEVEC_SIZE as a desired number of pages.

Just drop the argument.

Link: http://lkml.kernel.org/r/20170726114704.7626-11-jack@suse.cz
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agomm: use find_get_pages_range() in filemap_range_has_page()
Jan Kara [Wed, 6 Sep 2017 23:21:40 +0000 (16:21 -0700)]
mm: use find_get_pages_range() in filemap_range_has_page()

We want only pages from given range in filemap_range_has_page(),
furthermore we want at most a single page.

So use find_get_pages_range() instead of pagevec_lookup() and remove
unnecessary code.

Link: http://lkml.kernel.org/r/20170726114704.7626-10-jack@suse.cz
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agofs: use pagevec_lookup_range() in page_cache_seek_hole_data()
Jan Kara [Wed, 6 Sep 2017 23:21:37 +0000 (16:21 -0700)]
fs: use pagevec_lookup_range() in page_cache_seek_hole_data()

We want only pages from given range in page_cache_seek_hole_data().  Use
pagevec_lookup_range() instead of pagevec_lookup() and remove
unnecessary code.

Note that the check for getting less pages than desired can be removed
because index gets updated by pagevec_lookup_range().

Link: http://lkml.kernel.org/r/20170726114704.7626-9-jack@suse.cz
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agohugetlbfs: use pagevec_lookup_range() in remove_inode_hugepages()
Jan Kara [Wed, 6 Sep 2017 23:21:33 +0000 (16:21 -0700)]
hugetlbfs: use pagevec_lookup_range() in remove_inode_hugepages()

We want only pages from given range in remove_inode_hugepages().  Use
pagevec_lookup_range() instead of pagevec_lookup().

Link: http://lkml.kernel.org/r/20170726114704.7626-8-jack@suse.cz
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Nadia Yvette Chambers <nyc@holomorphy.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agoext4: use pagevec_lookup_range() in writeback code
Jan Kara [Wed, 6 Sep 2017 23:21:30 +0000 (16:21 -0700)]
ext4: use pagevec_lookup_range() in writeback code

Both occurences of pagevec_lookup() actually want only pages from a
given range.  Use pagevec_lookup_range() for the lookup.

Link: http://lkml.kernel.org/r/20170726114704.7626-7-jack@suse.cz
Signed-off-by: Jan Kara <jack@suse.cz>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agoext4: use pagevec_lookup_range() in ext4_find_unwritten_pgoff()
Jan Kara [Wed, 6 Sep 2017 23:21:27 +0000 (16:21 -0700)]
ext4: use pagevec_lookup_range() in ext4_find_unwritten_pgoff()

Use pagevec_lookup_range() in ext4_find_unwritten_pgoff() since we are
interested only in pages in the given range.  Simplify the logic as a
result of not getting pages out of range and index getting automatically
advanced.

Link: http://lkml.kernel.org/r/20170726114704.7626-6-jack@suse.cz
Signed-off-by: Jan Kara <jack@suse.cz>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agofs: fix performance regression in clean_bdev_aliases()
Jan Kara [Wed, 6 Sep 2017 23:21:24 +0000 (16:21 -0700)]
fs: fix performance regression in clean_bdev_aliases()

Commit e64855c6cfaa ("fs: Add helper to clean bdev aliases under a bh
and use it") added a wrapper for clean_bdev_aliases() that invalidates
bdev aliases underlying a single buffer head.

However this has caused a performance regression for bonnie++ benchmark
on ext4 filesystem when delayed allocation is turned off (ext3 mode) -
average of 3 runs:

  Hmean SeqOut Char  164787.55 (  0.00%) 107189.06 (-34.95%)
  Hmean SeqOut Block 219883.89 (  0.00%) 168870.32 (-23.20%)

The reason for this regression is that clean_bdev_aliases() is slower
when called for a single block because pagevec_lookup() it uses will end
up iterating through the radix tree until it finds a page (which may
take a while) but we are only interested whether there's a page at a
particular index.

Fix the problem by using pagevec_lookup_range() instead which avoids the
needless iteration.

Fixes: e64855c6cfaa ("fs: Add helper to clean bdev aliases under a bh and use it")
Link: http://lkml.kernel.org/r/20170726114704.7626-5-jack@suse.cz
Signed-off-by: Jan Kara <jack@suse.cz>
Cc: Jens Axboe <axboe@fb.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agomm: implement find_get_pages_range()
Jan Kara [Wed, 6 Sep 2017 23:21:21 +0000 (16:21 -0700)]
mm: implement find_get_pages_range()

Implement a variant of find_get_pages() that stops iterating at given
index.  This may be substantial performance gain if the mapping is
sparse.  See following commit for details.  Furthermore lots of users of
this function (through pagevec_lookup()) actually want a range lookup
and all of them are currently open-coding this.

Also create corresponding pagevec_lookup_range() function.

Link: http://lkml.kernel.org/r/20170726114704.7626-4-jack@suse.cz
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agomm: make pagevec_lookup() update index
Jan Kara [Wed, 6 Sep 2017 23:21:18 +0000 (16:21 -0700)]
mm: make pagevec_lookup() update index

Make pagevec_lookup() (and underlying find_get_pages()) update index to
the next page where iteration should continue.  Most callers want this
and also pagevec_lookup_tag() already does this.

Link: http://lkml.kernel.org/r/20170726114704.7626-3-jack@suse.cz
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agofscache: remove unused ->now_uncached callback
Jan Kara [Wed, 6 Sep 2017 23:21:15 +0000 (16:21 -0700)]
fscache: remove unused ->now_uncached callback

Patch series "Ranged pagevec lookup", v2.

In this series I make pagevec_lookup() update the index (to be
consistent with pagevec_lookup_tag() and also as a preparation for
ranged lookups), provide ranged variant of pagevec_lookup() and use it
in places where it makes sense.  This not only removes some common code
but is also a measurable performance win for some use cases (see patch
4/10) where radix tree is sparse and searching & grabing of a page after
the end of the range has measurable overhead.

This patch (of 10):

The callback doesn't ever get called.  Remove it.

Link: http://lkml.kernel.org/r/20170726114704.7626-2-jack@suse.cz
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agomm, vmscan: do not loop on too_many_isolated for ever
Michal Hocko [Wed, 6 Sep 2017 23:21:11 +0000 (16:21 -0700)]
mm, vmscan: do not loop on too_many_isolated for ever

Tetsuo Handa has reported[1][2][3] that direct reclaimers might get
stuck in too_many_isolated loop basically for ever because the last few
pages on the LRU lists are isolated by the kswapd which is stuck on fs
locks when doing the pageout or slab reclaim.  This in turn means that
there is nobody to actually trigger the oom killer and the system is
basically unusable.

too_many_isolated has been introduced by commit 35cd78156c49 ("vmscan:
throttle direct reclaim when too many pages are isolated already") to
prevent from pre-mature oom killer invocations because back then no
reclaim progress could indeed trigger the OOM killer too early.

But since the oom detection rework in commit 0a0337e0d1d1 ("mm, oom:
rework oom detection") the allocation/reclaim retry loop considers all
the reclaimable pages and throttles the allocation at that layer so we
can loosen the direct reclaim throttling.

Make shrink_inactive_list loop over too_many_isolated bounded and
returns immediately when the situation hasn't resolved after the first
sleep.

Replace congestion_wait by a simple schedule_timeout_interruptible
because we are not really waiting on the IO congestion in this path.

Please note that this patch can theoretically cause the OOM killer to
trigger earlier while there are many pages isolated for the reclaim
which makes progress only very slowly.  This would be obvious from the
oom report as the number of isolated pages are printed there.  If we
ever hit this should_reclaim_retry should consider those numbers in the
evaluation in one way or another.

[1] http://lkml.kernel.org/r/201602092349.ACG81273.OSVtMJQHLOFOFF@I-love.SAKURA.ne.jp
[2] http://lkml.kernel.org/r/201702212335.DJB30777.JOFMHSFtVLQOOF@I-love.SAKURA.ne.jp
[3] http://lkml.kernel.org/r/201706300914.CEH95859.FMQOLVFHJFtOOS@I-love.SAKURA.ne.jp

[mhocko@suse.com: switch to uninterruptible sleep]
Link: http://lkml.kernel.org/r/20170724065048.GB25221@dhcp22.suse.cz
Link: http://lkml.kernel.org/r/20170710074842.23175-1-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Tested-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Acked-by: Mel Gorman <mgorman@suse.de>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Rik van Riel <riel@redhat.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agozsmalloc: zs_page_migrate: skip unnecessary loops but not return -EBUSY if zspage...
Hui Zhu [Wed, 6 Sep 2017 23:21:08 +0000 (16:21 -0700)]
zsmalloc: zs_page_migrate: skip unnecessary loops but not return -EBUSY if zspage is not inuse

Getting -EBUSY from zs_page_migrate will make migration slow (retry) or
fail (zs_page_putback will schedule_work free_work, but it cannot ensure
the success).

I noticed this issue because my Kernel patched
(https://lkml.org/lkml/2014/5/28/113) that will remove retry in
__alloc_contig_migrate_range.

This retry will handle the -EBUSY because it will re-isolate the page
and re-call migrate_pages.  Without it will make cma_alloc fail at once
with -EBUSY.

According to the review from Minchan Kim in
https://lkml.org/lkml/2014/5/28/113, I update the patch to skip
unnecessary loops but not return -EBUSY if zspage is not inuse.

Following is what I got with highalloc-performance in a vbox with 2 cpu
1G memory 512 zram as swap.  And the swappiness is set to 100.

                                   ori          ne
                                  orig         new
Minor Faults                  50805113    50830235
Major Faults                     43918       56530
Swap Ins                         42087       55680
Swap Outs                        89718      104700
Allocation stalls                    0           0
DMA allocs                       57787       52364
DMA32 allocs                  47964599    48043563
Normal allocs                        0           0
Movable allocs                       0           0
Direct pages scanned             45493       23167
Kswapd pages scanned           1565222     1725078
Kswapd pages reclaimed         1342222     1503037
Direct pages reclaimed           45615       25186
Kswapd efficiency                  85%         87%
Kswapd velocity               1897.101    1949.042
Direct efficiency                 100%        108%
Direct velocity                 55.139      26.175
Percentage direct scans             2%          1%
Zone normal velocity          1952.240    1975.217
Zone dma32 velocity              0.000       0.000
Zone dma velocity                0.000       0.000
Page writes by reclaim       89764.000  105233.000
Page writes file                    46         533
Page writes anon                 89718      104700
Page reclaim immediate           21457        3699
Sector Reads                   3259688     3441368
Sector Writes                  3667252     3754836
Page rescued immediate               0           0
Slabs scanned                  1042872     1160855
Direct inode steals               8042       10089
Kswapd inode steals              54295       29170
Kswapd skipped wait                  0           0
THP fault alloc                    175         154
THP collapse alloc                 226         289
THP splits                           0           0
THP fault fallback                  11          14
THP collapse fail                    3           2
Compaction stalls                  536         646
Compaction success                 322         358
Compaction failures                214         288
Page migrate success            119608      111063
Page migrate failure              2723        2593
Compaction pages isolated       250179      232652
Compaction migrate scanned     9131832     9942306
Compaction free scanned        2093272     2613998
Compaction cost                    192         189
NUMA alloc hit                47124555    47193990
NUMA alloc miss                      0           0
NUMA interleave hit                  0           0
NUMA alloc local              47124555    47193990
NUMA base PTE updates                0           0
NUMA huge PMD updates                0           0
NUMA page range updates              0           0
NUMA hint faults                     0           0
NUMA hint local faults               0           0
NUMA hint local percent            100         100
NUMA pages migrated                  0           0
AutoNUMA cost                       0%          0%

[akpm@linux-foundation.org: remove newline, per Minchan]
Link: http://lkml.kernel.org/r/1500889535-19648-1-git-send-email-zhuhui@xiaomi.com
Signed-off-by: Hui Zhu <zhuhui@xiaomi.com>
Acked-by: Minchan Kim <minchan@kernel.org>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agomm: always flush VMA ranges affected by zap_page_range
Mel Gorman [Wed, 6 Sep 2017 23:21:05 +0000 (16:21 -0700)]
mm: always flush VMA ranges affected by zap_page_range

Nadav Amit report zap_page_range only specifies that the caller protect
the VMA list but does not specify whether it is held for read or write
with callers using either.  madvise holds mmap_sem for read meaning that
a parallel zap operation can unmap PTEs which are then potentially
skipped by madvise which potentially returns with stale TLB entries
present.  While the API could be extended, it would be a difficult API
to use.  This patch causes zap_page_range() to always consider flushing
the full affected range.  For small ranges or sparsely populated
mappings, this may result in one additional spurious TLB flush.  For
larger ranges, it is possible that the TLB has already been flushed and
the overhead is negligible.  Either way, this approach is safer overall
and avoids stale entries being present when madvise returns.

This can be illustrated with the following program provided by Nadav
Amit and slightly modified.  With the patch applied, it has an exit code
of 0 indicating a stale TLB entry did not leak to userspace.

---8<---

volatile int sync_step = 0;
volatile char *p;

static inline unsigned long rdtsc()
{
unsigned long hi, lo;
__asm__ __volatile__ ("rdtsc" : "=a"(lo), "=d"(hi));
 return lo | (hi << 32);
}

static inline void wait_rdtsc(unsigned long cycles)
{
unsigned long tsc = rdtsc();

while (rdtsc() - tsc < cycles);
}

void *big_madvise_thread(void *ign)
{
sync_step = 1;
while (sync_step != 2);
madvise((void*)p, PAGE_SIZE * N_PAGES, MADV_DONTNEED);
}

int main(void)
{
pthread_t aux_thread;

p = mmap(0, PAGE_SIZE * N_PAGES, PROT_READ|PROT_WRITE,
 MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);

memset((void*)p, 8, PAGE_SIZE * N_PAGES);

pthread_create(&aux_thread, NULL, big_madvise_thread, NULL);
while (sync_step != 1);

*p = 8; // Cache in TLB
sync_step = 2;
wait_rdtsc(100000);
madvise((void*)p, PAGE_SIZE, MADV_DONTNEED);
printf("data: %d (%s)\n", *p, (*p == 8 ? "stale, broken" : "cleared, fine"));
return *p == 8 ? -1 : 0;
}
---8<---

Link: http://lkml.kernel.org/r/20170725101230.5v7gvnjmcnkzzql3@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@suse.de>
Reported-by: Nadav Amit <nadav.amit@gmail.com>
Cc: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agomm/hugetlb.c: make huge_pte_offset() consistent and document behaviour
Punit Agrawal [Wed, 6 Sep 2017 23:21:01 +0000 (16:21 -0700)]
mm/hugetlb.c: make huge_pte_offset() consistent and document behaviour

When walking the page tables to resolve an address that points to
!p*d_present() entry, huge_pte_offset() returns inconsistent values
depending on the level of page table (PUD or PMD).

It returns NULL in the case of a PUD entry while in the case of a PMD
entry, it returns a pointer to the page table entry.

A similar inconsitency exists when handling swap entries - returns NULL
for a PUD entry while a pointer to the pte_t is retured for the PMD
entry.

Update huge_pte_offset() to make the behaviour consistent - return a
pointer to the pte_t for hugepage or swap entries.  Only return NULL in
instances where we have a p*d_none() entry and the size parameter
doesn't match the hugepage size at this level of the page table.

Document the behaviour to clarify the expected behaviour of this
function.  This is to set clear semantics for architecture specific
implementations of huge_pte_offset().

Discussions on the arm64 implementation of huge_pte_offset()
(http://www.spinics.net/lists/linux-mm/msg133699.html) showed that there
is benefit from returning a pte_t* in the case of p*d_none().

The fault handling code in hugetlb_fault() can handle p*d_none() entries
and saves an extra round trip to huge_pte_alloc().  Other callers of
huge_pte_offset() should be ok as well.

[punit.agrawal@arm.com: v2]
Link: http://lkml.kernel.org/r/20170725154114.24131-2-punit.agrawal@arm.com
Signed-off-by: Punit Agrawal <punit.agrawal@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Steve Capper <steve.capper@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agomm/gup: make __gup_device_* require THP
Oliver O'Halloran [Wed, 6 Sep 2017 23:20:58 +0000 (16:20 -0700)]
mm/gup: make __gup_device_* require THP

These functions are the only bits of generic code that use
{pud,pmd}_pfn() without checking for CONFIG_TRANSPARENT_HUGEPAGE.  This
works fine on x86, the only arch with devmap support, since the *_pfn()
functions are always defined there, but this isn't true for every
architecture.

Link: http://lkml.kernel.org/r/20170626063833.11094-1-oohall@gmail.com
Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agomm/mremap: fail map duplication attempts for private mappings
Mike Kravetz [Wed, 6 Sep 2017 23:20:55 +0000 (16:20 -0700)]
mm/mremap: fail map duplication attempts for private mappings

mremap will attempt to create a 'duplicate' mapping if old_size == 0 is
specified.  In the case of private mappings, mremap will actually create
a fresh separate private mapping unrelated to the original.  This does
not fit with the design semantics of mremap as the intention is to
create a new mapping based on the original.

Therefore, return EINVAL in the case where an attempt is made to
duplicate a private mapping.  Also, print a warning message (once) if
such an attempt is made.

Link: http://lkml.kernel.org/r/cb9d9f6a-7095-582f-15a5-62643d65c736@oracle.com
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Aaron Lu <aaron.lu@intel.com>
Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agomm, page_owner: don't grab zone->lock for init_pages_in_zone()
Vlastimil Babka [Wed, 6 Sep 2017 23:20:51 +0000 (16:20 -0700)]
mm, page_owner: don't grab zone->lock for init_pages_in_zone()

init_pages_in_zone() is run under zone->lock, which means a long lock
time and disabled interrupts on large machines.  This is currently not
an issue since it runs early in boot, but a later patch will change
that.

However, like other pfn scanners, we don't actually need zone->lock even
when other cpus are running.  The only potentially dangerous operation
here is reading bogus buddy page owner due to race, and we already know
how to handle that.  The worst that can happen is that we skip some
early allocated pages, which should not affect the debugging power of
page_owner noticeably.

Link: http://lkml.kernel.org/r/20170720134029.25268-4-vbabka@suse.cz
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Yang Shi <yang.shi@linaro.org>
Cc: Laura Abbott <labbott@redhat.com>
Cc: Vinayak Menon <vinmenon@codeaurora.org>
Cc: zhong jiang <zhongjiang@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agomm, page_ext: periodically reschedule during page_ext_init()
Vlastimil Babka [Wed, 6 Sep 2017 23:20:48 +0000 (16:20 -0700)]
mm, page_ext: periodically reschedule during page_ext_init()

page_ext_init() can take long on large machines, so add a cond_resched()
point after each section is processed.  This will allow moving the init
to a later point at boot without triggering lockup reports.

Link: http://lkml.kernel.org/r/20170720134029.25268-3-vbabka@suse.cz
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Yang Shi <yang.shi@linaro.org>
Cc: Laura Abbott <labbott@redhat.com>
Cc: Vinayak Menon <vinmenon@codeaurora.org>
Cc: zhong jiang <zhongjiang@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agomm, page_owner: make init_pages_in_zone() faster
Vlastimil Babka [Wed, 6 Sep 2017 23:20:44 +0000 (16:20 -0700)]
mm, page_owner: make init_pages_in_zone() faster

In init_pages_in_zone() we currently use the generic set_page_owner()
function to initialize page_owner info for early allocated pages.  This
means we needlessly do lookup_page_ext() twice for each page, and more
importantly save_stack(), which has to unwind the stack and find the
corresponding stack depot handle.  Because the stack is always the same
for the initialization, unwind it once in init_pages_in_zone() and reuse
the handle.  Also avoid the repeated lookup_page_ext().

This can significantly reduce boot times with page_owner=on on large
machines, especially for kernels built without frame pointer, where the
stack unwinding is noticeably slower.

[vbabka@suse.cz: don't duplicate code of __set_page_owner(), per Michal Hocko]
[akpm@linux-foundation.org: coding-style fixes]
[vbabka@suse.cz: create statically allocated fake stack trace for early allocated pages, per Michal]
Link: http://lkml.kernel.org/r/45813564-2342-fc8d-d31a-f4b68a724325@suse.cz
Link: http://lkml.kernel.org/r/20170720134029.25268-2-vbabka@suse.cz
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Yang Shi <yang.shi@linaro.org>
Cc: Laura Abbott <labbott@redhat.com>
Cc: Vinayak Menon <vinmenon@codeaurora.org>
Cc: zhong jiang <zhongjiang@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agomm, sparse, page_ext: drop ugly N_HIGH_MEMORY branches for allocations
Michal Hocko [Wed, 6 Sep 2017 23:20:41 +0000 (16:20 -0700)]
mm, sparse, page_ext: drop ugly N_HIGH_MEMORY branches for allocations

Commit f52407ce2dea ("memory hotplug: alloc page from other node in
memory online") has introduced N_HIGH_MEMORY checks to only use NUMA
aware allocations when there is some memory present because the
respective node might not have any memory yet at the time and so it
could fail or even OOM.

Things have changed since then though.  Zonelists are now always
initialized before we do any allocations even for hotplug (see
959ecc48fc75 ("mm/memory_hotplug.c: fix building of node hotplug
zonelist")).

Therefore these checks are not really needed.  In fact caller of the
allocator should never care about whether the node is populated because
that might change at any time.

Link: http://lkml.kernel.org/r/20170721143915.14161-10-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Shaohua Li <shaohua.li@intel.com>
Cc: Joonsoo Kim <js1304@gmail.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Toshi Kani <toshi.kani@hpe.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agomm, memory_hotplug: get rid of zonelists_mutex
Michal Hocko [Wed, 6 Sep 2017 23:20:37 +0000 (16:20 -0700)]
mm, memory_hotplug: get rid of zonelists_mutex

zonelists_mutex was introduced by commit 4eaf3f64397c ("mem-hotplug: fix
potential race while building zonelist for new populated zone") to
protect zonelist building from races.  This is no longer needed though
because both memory online and offline are fully serialized.  New users
have grown since then.

Notably setup_per_zone_wmarks wants to prevent from races between memory
hotplug, khugepaged setup and manual min_free_kbytes update via sysctl
(see cfd3da1e49bb ("mm: Serialize access to min_free_kbytes").  Let's
add a private lock for that purpose.  This will not prevent from seeing
halfway through memory hotplug operation but that shouldn't be a big
deal becuse memory hotplug will update watermarks explicitly so we will
eventually get a full picture.  The lock just makes sure we won't race
when updating watermarks leading to weird results.

Also __build_all_zonelists manipulates global data so add a private lock
for it as well.  This doesn't seem to be necessary today but it is more
robust to have a lock there.

While we are at it make sure we document that memory online/offline
depends on a full serialization either via mem_hotplug_begin() or
device_lock.

Link: http://lkml.kernel.org/r/20170721143915.14161-9-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Joonsoo Kim <js1304@gmail.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Shaohua Li <shaohua.li@intel.com>
Cc: Toshi Kani <toshi.kani@hpe.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Haicheng Li <haicheng.li@linux.intel.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agomm, page_alloc: remove stop_machine from build_all_zonelists
Michal Hocko [Wed, 6 Sep 2017 23:20:34 +0000 (16:20 -0700)]
mm, page_alloc: remove stop_machine from build_all_zonelists

build_all_zonelists has been (ab)using stop_machine to make sure that
zonelists do not change while somebody is looking at them.  This is is
just a gross hack because a) it complicates the context from which we
can call build_all_zonelists (see 3f906ba23689 ("mm/memory-hotplug:
switch locking to a percpu rwsem")) and b) is is not really necessary
especially after "mm, page_alloc: simplify zonelist initialization" and
c) it doesn't really provide the protection it claims (see below).

Updates of the zonelists happen very seldom, basically only when a zone
becomes populated during memory online or when it loses all the memory
during offline.  A racing iteration over zonelists could either miss a
zone or try to work on one zone twice.  Both of these are something we
can live with occasionally because there will always be at least one
zone visible so we are not likely to fail allocation too easily for
example.

Please note that the original stop_machine approach doesn't really
provide a better exclusion because the iteration might be interrupted
half way (unless the whole iteration is preempt disabled which is not
the case in most cases) so the some zones could still be seen twice or a
zone missed.

I have run the pathological online/offline of the single memblock in the
movable zone while stressing the same small node with some memory
pressure.

Node 1, zone      DMA
  pages free     0
        min      0
        low      0
        high     0
        spanned  0
        present  0
        managed  0
        protection: (0, 943, 943, 943)
Node 1, zone    DMA32
  pages free     227310
        min      8294
        low      10367
        high     12440
        spanned  262112
        present  262112
        managed  241436
        protection: (0, 0, 0, 0)
Node 1, zone   Normal
  pages free     0
        min      0
        low      0
        high     0
        spanned  0
        present  0
        managed  0
        protection: (0, 0, 0, 1024)
Node 1, zone  Movable
  pages free     32722
        min      85
        low      117
        high     149
        spanned  32768
        present  32768
        managed  32768
        protection: (0, 0, 0, 0)

root@test1:/sys/devices/system/node/node1# while true
do
echo offline > memory34/state
echo online_movable > memory34/state
done

root@test1:/mnt/data/test/linux-3.7-rc5# numactl --preferred=1 make -j4

and it survived without any unexpected behavior.  While this is not
really a great testing coverage it should exercise the allocation path
quite a lot.

Link: http://lkml.kernel.org/r/20170721143915.14161-8-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Joonsoo Kim <js1304@gmail.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Shaohua Li <shaohua.li@intel.com>
Cc: Toshi Kani <toshi.kani@hpe.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>
6 years agomm, page_alloc: simplify zonelist initialization
Michal Hocko [Wed, 6 Sep 2017 23:20:30 +0000 (16:20 -0700)]
mm, page_alloc: simplify zonelist initialization

build_zonelists gradually builds zonelists from the nearest to the most
distant node.  As we do not know how many populated zones we will have
in each node we rely on the _zoneref to terminate initialized part of
the zonelist by a NULL zone.  While this is functionally correct it is
quite suboptimal because we cannot allow updaters to race with zonelists
users because they could see an empty zonelist and fail the allocation
or hit the OOM killer in the worst case.

We can do much better, though.  We can store the node ordering into an
already existing node_order array and then give this array to
build_zonelists_in_node_order and do the whole initialization at once.
zonelists consumers still might see halfway initialized state but that
should be much more tolerateable because the list will not be empty and
they would either see some zone twice or skip over some zone(s) in the
worst case which shouldn't lead to immediate failures.

While at it let's simplify build_zonelists_node which is rather
confusing now.  It gets an index into the zoneref array and returns the
updated index for the next iteration.  Let's rename the function to
build_zonerefs_node to better reflect its purpose and give it zoneref
array to update.  The function doesn't the index anymore.  It just
returns the number of added zones so that the caller can advance the
zonered array start for the next update.

This patch alone doesn't introduce any functional change yet, though, it
is merely a preparatory work for later changes.

Link: http://lkml.kernel.org/r/20170721143915.14161-7-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Joonsoo Kim <js1304@gmail.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Shaohua Li <shaohua.li@intel.com>
Cc: Toshi Kani <toshi.kani@hpe.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agomm, memory_hotplug: remove explicit build_all_zonelists from try_online_node
Michal Hocko [Wed, 6 Sep 2017 23:20:27 +0000 (16:20 -0700)]
mm, memory_hotplug: remove explicit build_all_zonelists from try_online_node

try_online_node calls hotadd_new_pgdat which already calls
build_all_zonelists.  So the additional call is redundant.  Even though
hotadd_new_pgdat will only initialize zonelists of the new node this is
the right thing to do because such a node doesn't have any memory so
other zonelists would ignore all the zones from this node anyway.

Link: http://lkml.kernel.org/r/20170721143915.14161-6-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Toshi Kani <toshi.kani@hpe.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Joonsoo Kim <js1304@gmail.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agomm, memory_hotplug: drop zone from build_all_zonelists
Michal Hocko [Wed, 6 Sep 2017 23:20:24 +0000 (16:20 -0700)]
mm, memory_hotplug: drop zone from build_all_zonelists

build_all_zonelists gets a zone parameter to initialize zone's pagesets.
There is only a single user which gives a non-NULL zone parameter and
that one doesn't really need the rest of the build_all_zonelists (see
commit 6dcd73d7011b ("memory-hotplug: allocate zone's pcp before
onlining pages")).

Therefore remove setup_zone_pageset from build_all_zonelists and call it
from its only user directly.  This will also remove a pointless zonlists
rebuilding which is always good.

Link: http://lkml.kernel.org/r/20170721143915.14161-5-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Joonsoo Kim <js1304@gmail.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Shaohua Li <shaohua.li@intel.com>
Cc: Toshi Kani <toshi.kani@hpe.com>
Cc: Wen Congyang <wency@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agomm, page_alloc: do not set_cpu_numa_mem on empty nodes initialization
Michal Hocko [Wed, 6 Sep 2017 23:20:20 +0000 (16:20 -0700)]
mm, page_alloc: do not set_cpu_numa_mem on empty nodes initialization

__build_all_zonelists reinitializes each online cpu local node for
CONFIG_HAVE_MEMORYLESS_NODES.  This makes sense because previously
memory less nodes could gain some memory during memory hotplug and so
the local node should be changed for CPUs close to such a node.  It
makes less sense to do that unconditionally for a newly creaded NUMA
node which is still offline and without any memory.

Let's also simplify the cpu loop and use for_each_online_cpu instead of
an explicit cpu_online check for all possible cpus.

Link: http://lkml.kernel.org/r/20170721143915.14161-4-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Mel Gorman <mgorman@suse.de>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Joonsoo Kim <js1304@gmail.com>
Cc: Shaohua Li <shaohua.li@intel.com>
Cc: Toshi Kani <toshi.kani@hpe.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agomm, page_alloc: remove boot pageset initialization from memory hotplug
Michal Hocko [Wed, 6 Sep 2017 23:20:17 +0000 (16:20 -0700)]
mm, page_alloc: remove boot pageset initialization from memory hotplug

boot_pageset is a boot time hack which gets superseded by normal
pagesets later in the boot process.  It makes zero sense to reinitialize
it again and again during memory hotplug.

Link: http://lkml.kernel.org/r/20170721143915.14161-3-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Mel Gorman <mgorman@suse.de>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Joonsoo Kim <js1304@gmail.com>
Cc: Shaohua Li <shaohua.li@intel.com>
Cc: Toshi Kani <toshi.kani@hpe.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agomm, page_alloc: rip out ZONELIST_ORDER_ZONE
Michal Hocko [Wed, 6 Sep 2017 23:20:13 +0000 (16:20 -0700)]
mm, page_alloc: rip out ZONELIST_ORDER_ZONE

Patch series "cleanup zonelists initialization", v1.

This is aimed at cleaning up the zonelists initialization code we have
but the primary motivation was bug report [2] which got resolved but the
usage of stop_machine is just too ugly to live.  Most patches are
straightforward but 3 of them need a special consideration.

Patch 1 removes zone ordered zonelists completely.  I am CCing linux-api
because this is a user visible change.  As I argue in the patch
description I do not think we have a strong usecase for it these days.
I have kept sysctl in place and warn into the log if somebody tries to
configure zone lists ordering.  If somebody has a real usecase for it we
can revert this patch but I do not expect anybody will actually notice
runtime differences.  This patch is not strictly needed for the rest but
it made patch 6 easier to implement.

Patch 7 removes stop_machine from build_all_zonelists without adding any
special synchronization between iterators and updater which I _believe_
is acceptable as explained in the changelog.  I hope I am not missing
anything.

Patch 8 then removes zonelists_mutex which is kind of ugly as well and
not really needed AFAICS but a care should be taken when double checking
my thinking.

This patch (of 9):

Supporting zone ordered zonelists costs us just a lot of code while the
usefulness is arguable if existent at all.  Mel has already made node
ordering default on 64b systems.  32b systems are still using
ZONELIST_ORDER_ZONE because it is considered better to fallback to a
different NUMA node rather than consume precious lowmem zones.

This argument is, however, weaken by the fact that the memory reclaim
has been reworked to be node rather than zone oriented.  This means that
lowmem requests have to skip over all highmem pages on LRUs already and
so zone ordering doesn't save the reclaim time much.  So the only
advantage of the zone ordering is under a light memory pressure when
highmem requests do not ever hit into lowmem zones and the lowmem
pressure doesn't need to reclaim.

Considering that 32b NUMA systems are rather suboptimal already and it
is generally advisable to use 64b kernel on such a HW I believe we
should rather care about the code maintainability and just get rid of
ZONELIST_ORDER_ZONE altogether.  Keep systcl in place and warn if
somebody tries to set zone ordering either from kernel command line or
the sysctl.

[mhocko@suse.com: reading vm.numa_zonelist_order will never terminate]
Link: http://lkml.kernel.org/r/20170721143915.14161-2-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Mel Gorman <mgorman@suse.de>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Joonsoo Kim <js1304@gmail.com>
Cc: Shaohua Li <shaohua.li@intel.com>
Cc: Toshi Kani <toshi.kani@hpe.com>
Cc: Abdul Haleem <abdhalee@linux.vnet.ibm.com>
Cc: <linux-api@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agozram: add config and doc file for writeback feature
Minchan Kim [Wed, 6 Sep 2017 23:20:10 +0000 (16:20 -0700)]
zram: add config and doc file for writeback feature

This patch adds document and kconfig for using of writeback feature.

Link: http://lkml.kernel.org/r/1498459987-24562-10-git-send-email-minchan@kernel.org
Signed-off-by: Minchan Kim <minchan@kernel.org>
Cc: Juneho Choi <juno.choi@lge.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agozram: read page from backing device
Minchan Kim [Wed, 6 Sep 2017 23:20:07 +0000 (16:20 -0700)]
zram: read page from backing device

This patch enables read IO from backing device.  For the feature, it
implements two IO read functions to transfer data from backing storage.

One is asynchronous IO function and other is synchronous one.

A reason I need synchrnous IO is due to partial write which need to
complete read IO before the overwriting partial data.

We can make the partial IO's case asynchronous, too but at the moment, I
don't feel adding more complexity to support such rare use cases so want
to go with simple.

[xieyisheng1@huawei.com: read_from_bdev_async(): return 1 to avoid call page_endio() in zram_rw_page()]
Link: http://lkml.kernel.org/r/1502707447-6944-1-git-send-email-xieyisheng1@huawei.com
Link: http://lkml.kernel.org/r/1498459987-24562-9-git-send-email-minchan@kernel.org
Signed-off-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Yisheng Xie <xieyisheng1@huawei.com>
Cc: Juneho Choi <juno.choi@lge.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agozram: write incompressible pages to backing device
Minchan Kim [Wed, 6 Sep 2017 23:20:03 +0000 (16:20 -0700)]
zram: write incompressible pages to backing device

This patch enables write IO to transfer data to backing device.  For
that, it implements write_to_bdev function which creates new bio and
chaining with parent bio to make the parent bio asynchrnous.

For rw_page which don't have parent bio, it submit owned bio and handle
IO completion by zram_page_end_io.

Also, this patch defines new flag ZRAM_WB to mark written page for later
read IO.

[xieyisheng1@huawei.com: fix typo in comment]
Link: http://lkml.kernel.org/r/1502707447-6944-2-git-send-email-xieyisheng1@huawei.com
Link: http://lkml.kernel.org/r/1498459987-24562-8-git-send-email-minchan@kernel.org
Signed-off-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Yisheng Xie <xieyisheng1@huawei.com>
Cc: Juneho Choi <juno.choi@lge.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agozram: identify asynchronous IO's return value
Minchan Kim [Wed, 6 Sep 2017 23:20:00 +0000 (16:20 -0700)]
zram: identify asynchronous IO's return value

For upcoming asynchronous IO like writeback, zram_rw_page should be
aware of that whether requested IO was completed or submitted
successfully, otherwise error.

For the goal, zram_bvec_rw has three return values.

-errno: returns error number
     0: IO request is done synchronously
     1: IO request is issued successfully.

Link: http://lkml.kernel.org/r/1498459987-24562-7-git-send-email-minchan@kernel.org
Signed-off-by: Minchan Kim <minchan@kernel.org>
Cc: Juneho Choi <juno.choi@lge.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agozram: add free space management in backing device
Minchan Kim [Wed, 6 Sep 2017 23:19:57 +0000 (16:19 -0700)]
zram: add free space management in backing device

With backing device, zram needs management of free space of backing
device.

This patch adds bitmap logic to manage free space which is very naive.
However, it would be simple enough as considering uncompressible pages's
frequenty in zram.

Link: http://lkml.kernel.org/r/1498459987-24562-6-git-send-email-minchan@kernel.org
Signed-off-by: Minchan Kim <minchan@kernel.org>
Cc: Juneho Choi <juno.choi@lge.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agozram: add interface to specif backing device
Minchan Kim [Wed, 6 Sep 2017 23:19:54 +0000 (16:19 -0700)]
zram: add interface to specif backing device

For writeback feature, user should set up backing device before the zram
working.

This patch enables the interface via /sys/block/zramX/backing_dev.

Currently, it supports block device only but it could be enhanced for
file as well.

Link: http://lkml.kernel.org/r/1498459987-24562-5-git-send-email-minchan@kernel.org
Signed-off-by: Minchan Kim <minchan@kernel.org>
Cc: Juneho Choi <juno.choi@lge.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agozram: rename zram_decompress_page to __zram_bvec_read
Minchan Kim [Wed, 6 Sep 2017 23:19:50 +0000 (16:19 -0700)]
zram: rename zram_decompress_page to __zram_bvec_read

zram_decompress_page naming is not proper because it doesn't decompress
if page was dedup hit or stored with compression.

Use more abstract term and consistent with write path function
__zram_bvec_write.

Link: http://lkml.kernel.org/r/1498459987-24562-4-git-send-email-minchan@kernel.org
Signed-off-by: Minchan Kim <minchan@kernel.org>
Cc: Juneho Choi <juno.choi@lge.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agozram: inline zram_compress
Minchan Kim [Wed, 6 Sep 2017 23:19:47 +0000 (16:19 -0700)]
zram: inline zram_compress

zram_compress does several things, compress, entry alloc and check
limitation.  I did for just readbility but it hurts modulization.:(

So this patch removes zram_compress functions and inline it in
__zram_bvec_write for upcoming patches.

Link: http://lkml.kernel.org/r/1498459987-24562-3-git-send-email-minchan@kernel.org
Signed-off-by: Minchan Kim <minchan@kernel.org>
Cc: Juneho Choi <juno.choi@lge.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agozram: clean up duplicated codes in __zram_bvec_write
Minchan Kim [Wed, 6 Sep 2017 23:19:44 +0000 (16:19 -0700)]
zram: clean up duplicated codes in __zram_bvec_write

Patch series "writeback incompressible pages to storage", v1.

zRam is useful for memory saving with compressible pages but sometime,
workload can be changed and system has lots of incompressible pages
which is very harmful for zram.

This patch supports writeback feature of zram so admin can set up a
block device and with it, zram can save the memory via writing out the
incompressile pages once it found it's incompressible pages (1/4 comp
ratio) instead of keeping the page in memory.

[1-3] is just clean up and [4-8] is step by step feature enablement.
[4-8] is logically not bisectable(ie, logical unit separation)
although I tried to compiled out without breaking but I think it would
be better to review.

This patch (of 9):

__zram_bvec_write has some of duplicated logic for zram meta data
handling of same_page|compressed_page.  This patch aims to clean it up
without behavior change.

[xieyisheng1@huawei.com: fix compr_data_size stat]
Link: http://lkml.kernel.org/r/1502707447-6944-1-git-send-email-xieyisheng1@huawei.com
Link: http://lkml.kernel.org/r/1496019048-27016-1-git-send-email-minchan@kernel.org
Link: http://lkml.kernel.org/r/1498459987-24562-2-git-send-email-minchan@kernel.org
Signed-off-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Yisheng Xie <xieyisheng1@huawei.com>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Juneho Choi <juno.choi@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agomm, memory_hotplug: remove zone restrictions
Michal Hocko [Wed, 6 Sep 2017 23:19:40 +0000 (16:19 -0700)]
mm, memory_hotplug: remove zone restrictions

Historically we have enforced that any kernel zone (e.g ZONE_NORMAL) has
to precede the Movable zone in the physical memory range.  The purpose
of the movable zone is, however, not bound to any physical memory
restriction.  It merely defines a class of migrateable and reclaimable
memory.

There are users (e.g.  CMA) who might want to reserve specific physical
memory ranges for their own purpose.  Moreover our pfn walkers have to
be prepared for zones overlapping in the physical range already because
we do support interleaving NUMA nodes and therefore zones can interleave
as well.  This means we can allow each memory block to be associated
with a different zone.

Loosen the current onlining semantic and allow explicit onlining type on
any memblock.  That means that online_{kernel,movable} will be allowed
regardless of the physical address of the memblock as long as it is
offline of course.  This might result in moveble zone overlapping with
other kernel zones.  Default onlining then becomes a bit tricky but
still sensible.  echo online > memoryXY/state will online the given
block to

1) the default zone if the given range is outside of any zone
2) the enclosing zone if such a zone doesn't interleave with
   any other zone
        3) the default zone if more zones interleave for this range

where default zone is movable zone only if movable_node is enabled
otherwise it is a kernel zone.

Here is an example of the semantic with (movable_node is not present but
it work in an analogous way). We start with following memblocks, all of
them offline:

  memory34/valid_zones:Normal Movable
  memory35/valid_zones:Normal Movable
  memory36/valid_zones:Normal Movable
  memory37/valid_zones:Normal Movable
  memory38/valid_zones:Normal Movable
  memory39/valid_zones:Normal Movable
  memory40/valid_zones:Normal Movable
  memory41/valid_zones:Normal Movable

Now, we online block 34 in default mode and block 37 as movable

  root@test1:/sys/devices/system/node/node1# echo online > memory34/state
  root@test1:/sys/devices/system/node/node1# echo online_movable > memory37/state
  memory34/valid_zones:Normal
  memory35/valid_zones:Normal Movable
  memory36/valid_zones:Normal Movable
  memory37/valid_zones:Movable
  memory38/valid_zones:Normal Movable
  memory39/valid_zones:Normal Movable
  memory40/valid_zones:Normal Movable
  memory41/valid_zones:Normal Movable

As we can see all other blocks can still be onlined both into Normal and
Movable zones and the Normal is default because the Movable zone spans
only block37 now.

  root@test1:/sys/devices/system/node/node1# echo online_movable > memory41/state
  memory34/valid_zones:Normal
  memory35/valid_zones:Normal Movable
  memory36/valid_zones:Normal Movable
  memory37/valid_zones:Movable
  memory38/valid_zones:Movable Normal
  memory39/valid_zones:Movable Normal
  memory40/valid_zones:Movable Normal
  memory41/valid_zones:Movable

Now the default zone for blocks 37-41 has changed because movable zone
spans that range.

  root@test1:/sys/devices/system/node/node1# echo online_kernel > memory39/state
  memory34/valid_zones:Normal
  memory35/valid_zones:Normal Movable
  memory36/valid_zones:Normal Movable
  memory37/valid_zones:Movable
  memory38/valid_zones:Normal Movable
  memory39/valid_zones:Normal
  memory40/valid_zones:Movable Normal
  memory41/valid_zones:Movable

Note that the block 39 now belongs to the zone Normal and so block38
falls into Normal by default as well.

For completness

  root@test1:/sys/devices/system/node/node1# for i in memory[34]?
  do
echo online > $i/state 2>/dev/null
  done

  memory34/valid_zones:Normal
  memory35/valid_zones:Normal
  memory36/valid_zones:Normal
  memory37/valid_zones:Movable
  memory38/valid_zones:Normal
  memory39/valid_zones:Normal
  memory40/valid_zones:Movable
  memory41/valid_zones:Movable

Implementation wise the change is quite straightforward.  We can get rid
of allow_online_pfn_range altogether.  online_pages allows only offline
nodes already.  The original default_zone_for_pfn will become
default_kernel_zone_for_pfn.  New default_zone_for_pfn implements the
above semantic.  zone_for_pfn_range is slightly reorganized to implement
kernel and movable online type explicitly and MMOP_ONLINE_KEEP becomes a
catch all default behavior.

Link: http://lkml.kernel.org/r/20170714121233.16861-3-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Reza Arbab <arbab@linux.vnet.ibm.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Yasuaki Ishimatsu <yasu.isimatu@gmail.com>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Cc: Kani Toshimitsu <toshi.kani@hpe.com>
Cc: <slaoub@gmail.com>
Cc: Daniel Kiper <daniel.kiper@oracle.com>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: <linux-api@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agomm, memory_hotplug: display allowed zones in the preferred ordering
Michal Hocko [Wed, 6 Sep 2017 23:19:37 +0000 (16:19 -0700)]
mm, memory_hotplug: display allowed zones in the preferred ordering

Prior to commit f1dd2cd13c4b ("mm, memory_hotplug: do not associate
hotadded memory to zones until online") we used to allow to change the
valid zone types of a memory block if it is adjacent to a different zone
type.

This fact was reflected in memoryNN/valid_zones by the ordering of
printed zones.  The first one was default (echo online > memoryNN/state)
and the other one could be onlined explicitly by online_{movable,kernel}.

This behavior was removed by the said patch and as such the ordering was
not all that important.  In most cases a kernel zone would be default
anyway.  The only exception is movable_node handled by "mm,
memory_hotplug: support movable_node for hotpluggable nodes".

Let's reintroduce this behavior again because later patch will remove
the zone overlap restriction and so user will be allowed to online
kernel resp.  movable block regardless of its placement.  Original
behavior will then become significant again because it would be
non-trivial for users to see what is the default zone to online into.

Implementation is really simple.  Pull out zone selection out of
move_pfn_range into zone_for_pfn_range helper and use it in
show_valid_zones to display the zone for default onlining and then both
kernel and movable if they are allowed.  Default online zone is not
duplicated.

Link: http://lkml.kernel.org/r/20170714121233.16861-2-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Reza Arbab <arbab@linux.vnet.ibm.com>
Cc: Yasuaki Ishimatsu <yasu.isimatu@gmail.com>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Cc: Kani Toshimitsu <toshi.kani@hpe.com>
Cc: <slaoub@gmail.com>
Cc: Daniel Kiper <daniel.kiper@oracle.com>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agomm/memory_hotplug: just build zonelist for newly added node
Wei Yang [Wed, 6 Sep 2017 23:19:33 +0000 (16:19 -0700)]
mm/memory_hotplug: just build zonelist for newly added node

Commit 9adb62a5df9c ("mm/hotplug: correctly setup fallback zonelists
when creating new pgdat") tries to build the correct zonelist for a
newly added node, while it is not necessary to rebuild it for already
exist nodes.

In build_zonelists(), it will iterate on nodes with memory.  For a newly
added node, it will have memory until node_states_set_node() is called
in online_pages().

This patch avoids rebuilding the zonelists for already existing nodes.

build_zonelists_node() uses managed_zone(zone) checks, so it should not
include empty zones anyway.  So effectively we avoid some pointless work
under stop_machine().

[akpm@linux-foundation.org: tweak comment text]
[akpm@linux-foundation.org: coding-style tweak, per Vlastimil]
Link: http://lkml.kernel.org/r/20170626035822.50155-1-richard.weiyang@gmail.com
Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Jiang Liu <liuj97@gmail.com>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agodrm/i915: wire up shrinkctl->nr_scanned
Chris Wilson [Wed, 6 Sep 2017 23:19:30 +0000 (16:19 -0700)]
drm/i915: wire up shrinkctl->nr_scanned

shrink_slab() allows us to report back the number of objects we
successfully scanned (out of the target shrinkctl->nr_to_scan).  As
report the number of pages owned by each GEM object as a separate item
to the shrinker, we cannot precisely control the number of shrinker
objects we scan on each pass; and indeed may free more than requested.
If we fail to tell the shrinker about the number of objects we process,
it will continue to hold a grudge against us as any objects left
unscanned are added to the next reclaim -- and so we will keep on
"unfairly" shrinking our own slab in comparison to other slabs.

Link: http://lkml.kernel.org/r/20170822135325.9191-2-chris@chris-wilson.co.uk
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Shaohua Li <shli@fb.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Pekka Enberg <penberg@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agomm: track actual nr_scanned during shrink_slab()
Chris Wilson [Wed, 6 Sep 2017 23:19:26 +0000 (16:19 -0700)]
mm: track actual nr_scanned during shrink_slab()

Some shrinkers may only be able to free a bunch of objects at a time,
and so free more than the requested nr_to_scan in one pass.

Whilst other shrinkers may find themselves even unable to scan as many
objects as they counted, and so underreport.  Account for the extra
freed/scanned objects against the total number of objects we intend to
scan, otherwise we may end up penalising the slab far more than
intended.  Similarly, we want to add the underperforming scan to the
deferred pass so that we try harder and harder in future passes.

Link: http://lkml.kernel.org/r/20170822135325.9191-1-chris@chris-wilson.co.uk
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Shaohua Li <shli@fb.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>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agomm/slub.c: add a naive detection of double free or corruption
Alexander Popov [Wed, 6 Sep 2017 23:19:22 +0000 (16:19 -0700)]
mm/slub.c: add a naive detection of double free or corruption

Add an assertion similar to "fasttop" check in GNU C Library allocator
as a part of SLAB_FREELIST_HARDENED feature.  An object added to a
singly linked freelist should not point to itself.  That helps to detect
some double free errors (e.g. CVE-2017-2636) without slub_debug and
KASAN.

Link: http://lkml.kernel.org/r/1502468246-1262-1-git-send-email-alex.popov@linux.com
Signed-off-by: Alexander Popov <alex.popov@linux.com>
Acked-by: Christoph Lameter <cl@linux.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Paul E McKenney <paulmck@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Nicolas Pitre <nicolas.pitre@linaro.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Tycho Andersen <tycho@docker.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agomm: add SLUB free list pointer obfuscation
Kees Cook [Wed, 6 Sep 2017 23:19:18 +0000 (16:19 -0700)]
mm: add SLUB free list pointer obfuscation

This SLUB free list pointer obfuscation code is modified from Brad
Spengler/PaX Team's code in the last public patch of grsecurity/PaX
based on my understanding of the code.  Changes or omissions from the
original code are mine and don't reflect the original grsecurity/PaX
code.

This adds a per-cache random value to SLUB caches that is XORed with
their freelist pointer address and value.  This adds nearly zero
overhead and frustrates the very common heap overflow exploitation
method of overwriting freelist pointers.

A recent example of the attack is written up here:

  http://cyseclabs.com/blog/cve-2016-6187-heap-off-by-one-exploit

and there is a section dedicated to the technique the book "A Guide to
Kernel Exploitation: Attacking the Core".

This is based on patches by Daniel Micay, and refactored to minimize the
use of #ifdef.

With 200-count cycles of "hackbench -g 20 -l 1000" I saw the following
run times:

 before:
  mean 10.11882499999999999995
variance .03320378329145728642
stdev .18221905304181911048

  after:
mean 10.12654000000000000014
variance .04700556623115577889
stdev .21680767106160192064

The difference gets lost in the noise, but if the above is to be taken
literally, using CONFIG_FREELIST_HARDENED is 0.07% slower.

Link: http://lkml.kernel.org/r/20170802180609.GA66807@beast
Signed-off-by: Kees Cook <keescook@chromium.org>
Suggested-by: Daniel Micay <danielmicay@gmail.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Tycho Andersen <tycho@docker.com>
Cc: Alexander Popov <alex.popov@linux.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>
6 years agoslub: tidy up initialization ordering
Alexander Potapenko [Wed, 6 Sep 2017 23:19:15 +0000 (16:19 -0700)]
slub: tidy up initialization ordering

 - free_kmem_cache_nodes() frees the cache node before nulling out a
   reference to it

 - init_kmem_cache_nodes() publishes the cache node before initializing
   it

Neither of these matter at runtime because the cache nodes cannot be
looked up by any other thread.  But it's neater and more consistent to
reorder these.

Link: http://lkml.kernel.org/r/20170707083408.40410-1-glider@google.com
Signed-off-by: Alexander Potapenko <glider@google.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>
6 years agoocfs2: clean up some dead code
Jun Piao [Wed, 6 Sep 2017 23:19:11 +0000 (16:19 -0700)]
ocfs2: clean up some dead code

clean up some unused functions and parameters.

Link: http://lkml.kernel.org/r/598A5E21.2080807@huawei.com
Signed-off-by: Jun Piao <piaojun@huawei.com>
Reviewed-by: Alex Chen <alex.chen@huawei.com>
Cc: Mark Fasheh <mfasheh@versity.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Joseph Qi <jiangqi903@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agoocfs2: make ocfs2_set_acl() static
Jan Kara [Wed, 6 Sep 2017 23:19:08 +0000 (16:19 -0700)]
ocfs2: make ocfs2_set_acl() static

The function is never called outside of fs/ocfs2/acl.c.

Link: http://lkml.kernel.org/r/20170801141252.19675-2-jack@suse.cz
Signed-off-by: Jan Kara <jack@suse.cz>
Cc: Mark Fasheh <mfasheh@versity.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Joseph Qi <jiangqi903@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agomodpost: simplify sec_name()
Masahiro Yamada [Wed, 6 Sep 2017 23:19:05 +0000 (16:19 -0700)]
modpost: simplify sec_name()

There is code duplication between sec_name() and sech_name().  Simplify
sec_name() by re-using sech_name().  Also, move them up to remove the
forward declaration of sec_name().

Link: http://lkml.kernel.org/r/1502248721-22009-1-git-send-email-yamada.masahiro@socionext.com
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Jessica Yu <jeyu@redhat.com>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Heinrich Schuchardt <xypron.glpk@gmx.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agodax: initialize variable pfn before using it
Nicolas Iooss [Wed, 6 Sep 2017 23:19:01 +0000 (16:19 -0700)]
dax: initialize variable pfn before using it

dax_pmd_insert_mapping() contains the following code:

        pfn_t pfn;
        if (bdev_dax_pgoff(bdev, sector, size, &pgoff) != 0)
            goto fallback;
        /* ... */
    fallback:
      trace_dax_pmd_insert_mapping_fallback(inode, vmf, length, pfn, ret);

When the condition in the if statement fails, the function calls
trace_dax_pmd_insert_mapping_fallback() with an uninitialized pfn value.

This issue has been found while building the kernel with clang.  The
compiler reported:

    fs/dax.c:1280:6: error: variable 'pfn' is used uninitialized
    whenever 'if' condition is true [-Werror,-Wsometimes-uninitialized]
        if (bdev_dax_pgoff(bdev, sector, size, &pgoff) != 0)
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    fs/dax.c:1310:60: note: uninitialized use occurs here
      trace_dax_pmd_insert_mapping_fallback(inode, vmf, length, pfn, ret);
                                                                     ^~~

Link: http://lkml.kernel.org/r/20170903083000.587-1-nicolas.iooss_linux@m4x.org
Signed-off-by: Nicolas Iooss <nicolas.iooss_linux@m4x.org>
Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agodax: use PG_PMD_COLOUR instead of open coding
Ross Zwisler [Wed, 6 Sep 2017 23:18:58 +0000 (16:18 -0700)]
dax: use PG_PMD_COLOUR instead of open coding

Use ~PG_PMD_COLOUR in dax_entry_waitqueue() instead of open coding an
equivalent page offset mask.

Link: http://lkml.kernel.org/r/20170822222436.18926-2-ross.zwisler@linux.intel.com
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: "Slusarz, Marcin" <marcin.slusarz@intel.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agodax: explain how read(2)/write(2) addresses are validated
Ross Zwisler [Wed, 6 Sep 2017 23:18:54 +0000 (16:18 -0700)]
dax: explain how read(2)/write(2) addresses are validated

Add a comment explaining how the user addresses provided to read(2) and
write(2) are validated in the DAX I/O path.

We call dax_copy_from_iter() or copy_to_iter() on these without calling
access_ok() first in the DAX code, and there was a concern that the user
might be able to read/write to arbitrary kernel addresses with this
path.

Link: http://lkml.kernel.org/r/20170816173615.10098-1-ross.zwisler@linux.intel.com
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agodax: move all DAX radix tree defs to fs/dax.c
Ross Zwisler [Wed, 6 Sep 2017 23:18:51 +0000 (16:18 -0700)]
dax: move all DAX radix tree defs to fs/dax.c

Now that we no longer insert struct page pointers in DAX radix trees the
page cache code no longer needs to know anything about DAX exceptional
entries.  Move all the DAX exceptional entry definitions from dax.h to
fs/dax.c.

Link: http://lkml.kernel.org/r/20170724170616.25810-6-ross.zwisler@linux.intel.com
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Suggested-by: Jan Kara <jack@suse.cz>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: "Darrick J. Wong" <darrick.wong@oracle.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agodax: remove DAX code from page_cache_tree_insert()
Ross Zwisler [Wed, 6 Sep 2017 23:18:47 +0000 (16:18 -0700)]
dax: remove DAX code from page_cache_tree_insert()

Now that we no longer insert struct page pointers in DAX radix trees we
can remove the special casing for DAX in page_cache_tree_insert().

This also allows us to make dax_wake_mapping_entry_waiter() local to
fs/dax.c, removing it from dax.h.

Link: http://lkml.kernel.org/r/20170724170616.25810-5-ross.zwisler@linux.intel.com
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Suggested-by: Jan Kara <jack@suse.cz>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: "Darrick J. Wong" <darrick.wong@oracle.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agodax: use common 4k zero page for dax mmap reads
Ross Zwisler [Wed, 6 Sep 2017 23:18:43 +0000 (16:18 -0700)]
dax: use common 4k zero page for dax mmap reads

When servicing mmap() reads from file holes the current DAX code
allocates a page cache page of all zeroes and places the struct page
pointer in the mapping->page_tree radix tree.

This has three major drawbacks:

1) It consumes memory unnecessarily. For every 4k page that is read via
   a DAX mmap() over a hole, we allocate a new page cache page. This
   means that if you read 1GiB worth of pages, you end up using 1GiB of
   zeroed memory. This is easily visible by looking at the overall
   memory consumption of the system or by looking at /proc/[pid]/smaps:

7f62e72b3000-7f63272b3000 rw-s 00000000 103:00 12   /root/dax/data
Size:            1048576 kB
Rss:             1048576 kB
Pss:             1048576 kB
Shared_Clean:          0 kB
Shared_Dirty:          0 kB
Private_Clean:   1048576 kB
Private_Dirty:         0 kB
Referenced:      1048576 kB
Anonymous:             0 kB
LazyFree:              0 kB
AnonHugePages:         0 kB
ShmemPmdMapped:        0 kB
Shared_Hugetlb:        0 kB
Private_Hugetlb:       0 kB
Swap:                  0 kB
SwapPss:               0 kB
KernelPageSize:        4 kB
MMUPageSize:           4 kB
Locked:                0 kB

2) It is slower than using a common zero page because each page fault
   has more work to do. Instead of just inserting a common zero page we
   have to allocate a page cache page, zero it, and then insert it. Here
   are the average latencies of dax_load_hole() as measured by ftrace on
   a random test box:

    Old method, using zeroed page cache pages: 3.4 us
    New method, using the common 4k zero page: 0.8 us

   This was the average latency over 1 GiB of sequential reads done by
   this simple fio script:

     [global]
     size=1G
     filename=/root/dax/data
     fallocate=none
     [io]
     rw=read
     ioengine=mmap

3) The fact that we had to check for both DAX exceptional entries and
   for page cache pages in the radix tree made the DAX code more
   complex.

Solve these issues by following the lead of the DAX PMD code and using a
common 4k zero page instead.  As with the PMD code we will now insert a
DAX exceptional entry into the radix tree instead of a struct page
pointer which allows us to remove all the special casing in the DAX
code.

Note that we do still pretty aggressively check for regular pages in the
DAX radix tree, especially where we take action based on the bits set in
the page.  If we ever find a regular page in our radix tree now that
most likely means that someone besides DAX is inserting pages (which has
happened lots of times in the past), and we want to find that out early
and fail loudly.

This solution also removes the extra memory consumption.  Here is that
same /proc/[pid]/smaps after 1GiB of reading from a hole with the new
code:

7f2054a74000-7f2094a74000 rw-s 00000000 103:00 12   /root/dax/data
Size:            1048576 kB
Rss:                   0 kB
Pss:                   0 kB
Shared_Clean:          0 kB
Shared_Dirty:          0 kB
Private_Clean:         0 kB
Private_Dirty:         0 kB
Referenced:            0 kB
Anonymous:             0 kB
LazyFree:              0 kB
AnonHugePages:         0 kB
ShmemPmdMapped:        0 kB
Shared_Hugetlb:        0 kB
Private_Hugetlb:       0 kB
Swap:                  0 kB
SwapPss:               0 kB
KernelPageSize:        4 kB
MMUPageSize:           4 kB
Locked:                0 kB

Overall system memory consumption is similarly improved.

Another major change is that we remove dax_pfn_mkwrite() from our fault
flow, and instead rely on the page fault itself to make the PTE dirty
and writeable.  The following description from the patch adding the
vm_insert_mixed_mkwrite() call explains this a little more:

   "To be able to use the common 4k zero page in DAX we need to have our
    PTE fault path look more like our PMD fault path where a PTE entry
    can be marked as dirty and writeable as it is first inserted rather
    than waiting for a follow-up dax_pfn_mkwrite() =>
    finish_mkwrite_fault() call.

    Right now we can rely on having a dax_pfn_mkwrite() call because we
    can distinguish between these two cases in do_wp_page():

            case 1: 4k zero page => writable DAX storage
            case 2: read-only DAX storage => writeable DAX storage

    This distinction is made by via vm_normal_page(). vm_normal_page()
    returns false for the common 4k zero page, though, just as it does
    for DAX ptes. Instead of special casing the DAX + 4k zero page case
    we will simplify our DAX PTE page fault sequence so that it matches
    our DAX PMD sequence, and get rid of the dax_pfn_mkwrite() helper.
    We will instead use dax_iomap_fault() to handle write-protection
    faults.

    This means that insert_pfn() needs to follow the lead of
    insert_pfn_pmd() and allow us to pass in a 'mkwrite' flag. If
    'mkwrite' is set insert_pfn() will do the work that was previously
    done by wp_page_reuse() as part of the dax_pfn_mkwrite() call path"

Link: http://lkml.kernel.org/r/20170724170616.25810-4-ross.zwisler@linux.intel.com
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: "Darrick J. Wong" <darrick.wong@oracle.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agodax: relocate some dax functions
Ross Zwisler [Wed, 6 Sep 2017 23:18:39 +0000 (16:18 -0700)]
dax: relocate some dax functions

dax_load_hole() will soon need to call dax_insert_mapping_entry(), so it
needs to be moved lower in dax.c so the definition exists.

dax_wake_mapping_entry_waiter() will soon be removed from dax.h and be
made static to dax.c, so we need to move its definition above all its
callers.

Link: http://lkml.kernel.org/r/20170724170616.25810-3-ross.zwisler@linux.intel.com
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: "Darrick J. Wong" <darrick.wong@oracle.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agomm: add vm_insert_mixed_mkwrite()
Ross Zwisler [Wed, 6 Sep 2017 23:18:35 +0000 (16:18 -0700)]
mm: add vm_insert_mixed_mkwrite()

When servicing mmap() reads from file holes the current DAX code
allocates a page cache page of all zeroes and places the struct page
pointer in the mapping->page_tree radix tree.  This has three major
drawbacks:

1) It consumes memory unnecessarily. For every 4k page that is read via
   a DAX mmap() over a hole, we allocate a new page cache page. This
   means that if you read 1GiB worth of pages, you end up using 1GiB of
   zeroed memory.

2) It is slower than using a common zero page because each page fault
   has more work to do. Instead of just inserting a common zero page we
   have to allocate a page cache page, zero it, and then insert it.

3) The fact that we had to check for both DAX exceptional entries and
   for page cache pages in the radix tree made the DAX code more
   complex.

This series solves these issues by following the lead of the DAX PMD
code and using a common 4k zero page instead.  This reduces memory usage
and decreases latencies for some workloads, and it simplifies the DAX
code, removing over 100 lines in total.

This patch (of 5):

To be able to use the common 4k zero page in DAX we need to have our PTE
fault path look more like our PMD fault path where a PTE entry can be
marked as dirty and writeable as it is first inserted rather than
waiting for a follow-up dax_pfn_mkwrite() => finish_mkwrite_fault()
call.

Right now we can rely on having a dax_pfn_mkwrite() call because we can
distinguish between these two cases in do_wp_page():

case 1: 4k zero page => writable DAX storage
case 2: read-only DAX storage => writeable DAX storage

This distinction is made by via vm_normal_page().  vm_normal_page()
returns false for the common 4k zero page, though, just as it does for
DAX ptes.  Instead of special casing the DAX + 4k zero page case we will
simplify our DAX PTE page fault sequence so that it matches our DAX PMD
sequence, and get rid of the dax_pfn_mkwrite() helper.  We will instead
use dax_iomap_fault() to handle write-protection faults.

This means that insert_pfn() needs to follow the lead of
insert_pfn_pmd() and allow us to pass in a 'mkwrite' flag.  If 'mkwrite'
is set insert_pfn() will do the work that was previously done by
wp_page_reuse() as part of the dax_pfn_mkwrite() call path.

Link: http://lkml.kernel.org/r/20170724170616.25810-2-ross.zwisler@linux.intel.com
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: "Darrick J. Wong" <darrick.wong@oracle.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agometag/numa: remove the unused parent_node() macro
Dou Liyang [Wed, 6 Sep 2017 23:18:32 +0000 (16:18 -0700)]
metag/numa: remove the unused parent_node() macro

Commit a7be6e5a7f8d ("mm: drop useless local parameters of
__register_one_node()") removes the last user of parent_node().

The parent_node() macro in METAG architecture is unnecessary.

Remove it for cleanup.

Link: http://lkml.kernel.org/r/1501076076-1974-4-git-send-email-douly.fnst@cn.fujitsu.com
Signed-off-by: Dou Liyang <douly.fnst@cn.fujitsu.com>
Reported-by: Michael Ellerman <mpe@ellerman.id.au>
Cc: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agoMerge tag 'devprop-4.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael...
Linus Torvalds [Tue, 5 Sep 2017 19:50:00 +0000 (12:50 -0700)]
Merge tag 'devprop-4.14-rc1' of git://git./linux/kernel/git/rafael/linux-pm

Pull device properties framework updates from Rafael Wysocki:
 "These introduce fwnode operations for all of the separate types of
  'firmware nodes' that can be handled by the device properties
  framework, make the framework use const fwnode arguments all over, add
  a helper for the consolidated handling of node references and switch
  over the framework to the new UUID API.

  Specifics:

   - Introduce fwnode operations for all of the separate types of
     'firmware nodes' that can be handled by the device properties
     framework and drop the type field from struct fwnode_handle (Sakari
     Ailus, Arnd Bergmann).

   - Make the device properties framework use const fwnode arguments
     where possible (Sakari Ailus).

   - Add a helper for the consolidated handling of node references to
     the device properties framework (Sakari Ailus).

   - Switch over the ACPI part of the device properties framework to the
     new UUID API (Andy Shevchenko)"

* tag 'devprop-4.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPI: device property: Switch to use new generic UUID API
  device property: export irqchip_fwnode_ops
  device property: Introduce fwnode_property_get_reference_args
  device property: Constify fwnode property API
  device property: Constify argument to pset fwnode backend
  ACPI: Constify internal fwnode arguments
  ACPI: Constify acpi_bus helper functions, switch to macros
  ACPI: Prepare for constifying acpi_get_next_subnode() fwnode argument
  device property: Get rid of struct fwnode_handle type field
  ACPI: Use IS_ERR_OR_NULL() instead of non-NULL check in is_acpi_data_node()

6 years agoMerge tag 'acpi-4.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael...
Linus Torvalds [Tue, 5 Sep 2017 19:45:03 +0000 (12:45 -0700)]
Merge tag 'acpi-4.14-rc1' of git://git./linux/kernel/git/rafael/linux-pm

Pull ACPI updates from Rafael Wysocki:
 "These include a usual ACPICA code update (this time to upstream
  revision 20170728), a fix for a boot crash on some systems with
  Thunderbolt devices connected at boot time, a rework of the handling
  of PCI bridges when setting up device wakeup, new support for Apple
  device properties, support for DMA configurations reported via ACPI on
  ARM64, APEI-related updates, ACPI EC driver updates and assorted minor
  modifications in several places.

  Specifics:

   - Update the ACPICA code in the kernel to upstream revision 20170728
     including:
      * Alias operator handling update (Bob Moore).
      * Deferred resolution of reference package elements (Bob Moore).
      * Support for the _DMA method in walk resources (Bob Moore).
      * Tables handling update and support for deferred table
        verification (Lv Zheng).
      * Update of SMMU models for IORT (Robin Murphy).
      * Compiler and disassembler updates (Alex James, Erik Schmauss,
        Ganapatrao Kulkarni, James Morse).
      * Tools updates (Erik Schmauss, Lv Zheng).
      * Assorted minor fixes and cleanups (Bob Moore, Kees Cook, Lv
        Zheng, Shao Ming).

   - Rework the initialization of non-wakeup GPEs with method handlers
     in order to address a boot crash on some systems with Thunderbolt
     devices connected at boot time where we miss an early hotplug event
     due to a delay in GPE enabling (Rafael Wysocki).

   - Rework the handling of PCI bridges when setting up ACPI-based
     device wakeup in order to avoid disabling wakeup for bridges
     prematurely (Rafael Wysocki).

   - Consolidate Apple DMI checks throughout the tree, add support for
     Apple device properties to the device properties framework and use
     these properties for the handling of I2C and SPI devices on Apple
     systems (Lukas Wunner).

   - Add support for _DMA to the ACPI-based device properties lookup
     code and make it possible to use the information from there to
     configure DMA regions on ARM64 systems (Lorenzo Pieralisi).

   - Fix several issues in the APEI code, add support for exporting the
     BERT error region over sysfs and update APEI MAINTAINERS entry with
     reviewers information (Borislav Petkov, Dongjiu Geng, Loc Ho, Punit
     Agrawal, Tony Luck, Yazen Ghannam).

   - Fix a potential initialization ordering issue in the ACPI EC driver
     and clean it up somewhat (Lv Zheng).

   - Update the ACPI SPCR driver to extend the existing XGENE 8250
     workaround in it to a new platform (m400) and to work around an
     Xgene UART clock issue (Graeme Gregory).

   - Add a new utility function to the ACPI core to support using ACPI
     OEM ID / OEM Table ID / Revision for system identification in
     blacklisting or similar and switch over the existing code already
     using this information to this new interface (Toshi Kani).

   - Fix an xpower PMIC issue related to GPADC reads that always return
     0 without extra pin manipulations (Hans de Goede).

   - Add statements to print debug messages in a couple of places in the
     ACPI core for easier diagnostics (Rafael Wysocki).

   - Clean up the ACPI processor driver slightly (Colin Ian King, Hanjun
     Guo).

   - Clean up the ACPI x86 boot code somewhat (Andy Shevchenko).

   - Add a quirk for Dell OptiPlex 9020M to the ACPI backlight driver
     (Alex Hung).

   - Assorted fixes, cleanups and updates related to ACPI (Amitoj Kaur
     Chawla, Bhumika Goyal, Frank Rowand, Jean Delvare, Punit Agrawal,
     Ronald Tschalär, Sumeet Pawnikar)"

* tag 'acpi-4.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (75 commits)
  ACPI / APEI: Suppress message if HEST not present
  intel_pstate: convert to use acpi_match_platform_list()
  ACPI / blacklist: add acpi_match_platform_list()
  ACPI, APEI, EINJ: Subtract any matching Register Region from Trigger resources
  ACPI: make device_attribute const
  ACPI / sysfs: Extend ACPI sysfs to provide access to boot error region
  ACPI: APEI: fix the wrong iteration of generic error status block
  ACPI / processor: make function acpi_processor_check_duplicates() static
  ACPI / EC: Clean up EC GPE mask flag
  ACPI: EC: Fix possible issues related to EC initialization order
  ACPI / PM: Add debug statements to acpi_pm_notify_handler()
  ACPI: Add debug statements to acpi_global_event_handler()
  ACPI / scan: Enable GPEs before scanning the namespace
  ACPICA: Make it possible to enable runtime GPEs earlier
  ACPICA: Dispatch active GPEs at init time
  ACPI: SPCR: work around clock issue on xgene UART
  ACPI: SPCR: extend XGENE 8250 workaround to m400
  ACPI / LPSS: Don't abort ACPI scan on missing mem resource
  mailbox: pcc: Drop uninformative output during boot
  ACPI/IORT: Add IORT named component memory address limits
  ...

6 years agoMerge tag 'pm-4.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Linus Torvalds [Tue, 5 Sep 2017 19:19:08 +0000 (12:19 -0700)]
Merge tag 'pm-4.14-rc1' of git://git./linux/kernel/git/rafael/linux-pm

Pull power management updates from Rafael Wysocki:
 "This time (again) cpufreq gets the majority of changes which mostly
  are driver updates (including a major consolidation of intel_pstate),
  some schedutil governor modifications and core cleanups.

  There also are some changes in the system suspend area, mostly related
  to diagnostics and debug messages plus some renames of things related
  to suspend-to-idle. One major change here is that suspend-to-idle is
  now going to be preferred over S3 on systems where the ACPI tables
  indicate to do so and provide requsite support (the Low Power Idle S0
  _DSM in particular). The system sleep documentation and the tools
  related to it are updated too.

  The rest is a few cpuidle changes (nothing major), devfreq updates,
  generic power domains (genpd) framework updates and a few assorted
  modifications elsewhere.

  Specifics:

   - Drop the P-state selection algorithm based on a PID controller from
     intel_pstate and make it use the same P-state selection method
     (based on the CPU load) for all types of systems in the active mode
     (Rafael Wysocki, Srinivas Pandruvada).

   - Rework the cpufreq core and governors to make it possible to take
     cross-CPU utilization updates into account and modify the schedutil
     governor to actually do so (Viresh Kumar).

   - Clean up the handling of transition latency information in the
     cpufreq core and untangle it from the information on which drivers
     cannot do dynamic frequency switching (Viresh Kumar).

   - Add support for new SoCs (MT2701/MT7623 and MT7622) to the mediatek
     cpufreq driver and update its DT bindings (Sean Wang).

   - Modify the cpufreq dt-platdev driver to autimatically create
     cpufreq devices for the new (v2) Operating Performance Points (OPP)
     DT bindings and update its whitelist of supported systems (Viresh
     Kumar, Shubhrajyoti Datta, Marc Gonzalez, Khiem Nguyen, Finley
     Xiao).

   - Add support for Ux500 to the cpufreq-dt driver and drop the
     obsolete dbx500 cpufreq driver (Linus Walleij, Arnd Bergmann).

   - Add new SoC (R8A7795) support to the cpufreq rcar driver (Khiem
     Nguyen).

   - Fix and clean up assorted issues in the cpufreq drivers and core
     (Arvind Yadav, Christophe Jaillet, Colin Ian King, Gustavo Silva,
     Julia Lawall, Leonard Crestez, Rob Herring, Sudeep Holla).

   - Update the IO-wait boost handling in the schedutil governor to make
     it less aggressive (Joel Fernandes).

   - Rework system suspend diagnostics to make it print fewer messages
     to the kernel log by default, add a sysfs knob to allow more
     suspend-related messages to be printed and add Low Power S0 Idle
     constraints checks to the ACPI suspend-to-idle code (Rafael
     Wysocki, Srinivas Pandruvada).

   - Prefer suspend-to-idle over S3 on ACPI-based systems with the
     ACPI_FADT_LOW_POWER_S0 flag set and the Low Power Idle S0 _DSM
     interface present in the ACPI tables (Rafael Wysocki).

   - Update documentation related to system sleep and rename a number of
     items in the code to make it cleare that they are related to
     suspend-to-idle (Rafael Wysocki).

   - Export a variable allowing device drivers to check the target
     system sleep state from the core system suspend code (Florian
     Fainelli).

   - Clean up the cpuidle subsystem to handle the polling state on x86
     in a more straightforward way and to use %pOF instead of full_name
     (Rafael Wysocki, Rob Herring).

   - Update the devfreq framework to fix and clean up a few minor issues
     (Chanwoo Choi, Rob Herring).

   - Extend diagnostics in the generic power domains (genpd) framework
     and clean it up slightly (Thara Gopinath, Rob Herring).

   - Fix and clean up a couple of issues in the operating performance
     points (OPP) framework (Viresh Kumar, Waldemar Rymarkiewicz).

   - Add support for RV1108 to the rockchip-io Adaptive Voltage Scaling
     (AVS) driver (David Wu).

   - Fix the usage of notifiers in CPU power management on some
     platforms (Alex Shi).

   - Update the pm-graph system suspend/hibernation and boot profiling
     utility (Todd Brandt).

   - Make it possible to run the cpupower utility without CPU0 (Prarit
     Bhargava)"

* tag 'pm-4.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (87 commits)
  cpuidle: Make drivers initialize polling state
  cpuidle: Move polling state initialization code to separate file
  cpuidle: Eliminate the CPUIDLE_DRIVER_STATE_START symbol
  cpufreq: imx6q: Fix imx6sx low frequency support
  cpufreq: speedstep-lib: make several arrays static, makes code smaller
  PM: docs: Delete the obsolete states.txt document
  PM: docs: Describe high-level PM strategies and sleep states
  PM / devfreq: Fix memory leak when fail to register device
  PM / devfreq: Add dependency on PM_OPP
  PM / devfreq: Move private devfreq_update_stats() into devfreq
  PM / devfreq: Convert to using %pOF instead of full_name
  PM / AVS: rockchip-io: add io selectors and supplies for RV1108
  cpufreq: ti: Fix 'of_node_put' being called twice in error handling path
  cpufreq: dt-platdev: Drop few entries from whitelist
  cpufreq: dt-platdev: Automatically create cpufreq device with OPP v2
  ARM: ux500: don't select CPUFREQ_DT
  cpuidle: Convert to using %pOF instead of full_name
  cpufreq: Convert to using %pOF instead of full_name
  PM / Domains: Convert to using %pOF instead of full_name
  cpufreq: Cap the default transition delay value to 10 ms
  ...

6 years agoMerge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid
Linus Torvalds [Tue, 5 Sep 2017 18:54:41 +0000 (11:54 -0700)]
Merge branch 'for-linus' of git://git./linux/kernel/git/jikos/hid

Pull HID update from Jiri Kosina:

 - Wacom driver fixes/updates (device name generation improvements,
   touch ring status support) from Jason Gerecke

 - T100 touchpad support from Hans de Goede

 - support for batteries driven by HID input reports, from Dmitry
   Torokhov

 - Arnd pointed out that driver_lock semaphore is superfluous, as driver
   core already provides all the necessary concurency protection.
   Removal patch from Binoy Jayan

 - logical minimum numbering improvements in sensor-hub driver, from
   Srinivas Pandruvada

 - support for Microsoft Win8 Wireless Radio Controls extensions from
   João Paulo Rechi Vita

 - assorted small fixes and device ID additions

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid: (28 commits)
  HID: prodikeys: constify snd_rawmidi_ops structures
  HID: sensor: constify platform_device_id
  HID: input: throttle battery uevents
  HID: usbmouse: constify usb_device_id and fix space before '[' error
  HID: usbkbd: constify usb_device_id and fix space before '[' error.
  HID: hid-sensor-hub: Force logical minimum to 1 for power and report state
  HID: wacom: Do not completely map WACOM_HID_WD_TOUCHRINGSTATUS usage
  HID: asus: Add T100CHI bluetooth keyboard dock touchpad support
  HID: ntrig: constify attribute_group structures.
  HID: logitech-hidpp: constify attribute_group structures.
  HID: sensor: constify attribute_group structures.
  HID: multitouch: constify attribute_group structures.
  HID: multitouch: use proper symbolic constant for 0xff310076 application
  HID: multitouch: Support Asus T304UA media keys
  HID: multitouch: Support HID_GD_WIRELESS_RADIO_CTLS
  HID: input: optionally use device id in battery name
  HID: input: map digitizer battery usage
  HID: Remove the semaphore driver_lock
  HID: wacom: add USB_HID dependency
  HID: add ALWAYS_POLL quirk for Logitech 0xc077
  ...

6 years agoMerge tag 'gpio-v4.14-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw...
Linus Torvalds [Tue, 5 Sep 2017 18:49:48 +0000 (11:49 -0700)]
Merge tag 'gpio-v4.14-1' of git://git./linux/kernel/git/linusw/linux-gpio

Pull GPIO updates from Linus Walleij:
 "This is the bulk of the GPIO changes for the v4.14 cycle.

  Not so much changes this time, phew. David Daney and Bartosz
  Golaszewski did all the really interesting work in infrastructure
  improvement across GPIO and IRQ core, hats off for them and to tglx
  and Marc Z for general help with these patch sets.

  Core changes:

   - Allow the GPIO irqchip to allocate IRQs dynamically. This is an
     important change on systems where only a restricted number of IRQs,
     lesser than the number of GPIO lines, can be utilized. Now we can
     allocate these on a first-come-first-served basis instead of
     hogging up valuable IRQ lines.

   - Serious fix-up of the kerneldoc documentation and inclusion into
     the kerneldoc builds.

   - Pulled in the IRQ simulator from the IRQ core tree and use this in
     the GPIO mockup driver for exhaustive testing of interrupt
     abilities.

  New drivers:

   - New driver for ThunderX and OCTEON-TX. This is especially
     interesting as it picks up improvements from the IRQ core that
     allow us to handle fasteoi ACKs upwards in a hierarchy when there
     are IRQ flag latches on several levels in a hierarchy. Very
     interesting work here.

   - New subdriver for Renesas R-Car r8a7745 (RZ/G1E).

  Misc:

   - Several fixes and improvements for Xilinx Zynq GPIO.

   - Support an enablement GPIO for the 74x164 GPIO.

   - Switch a bunch of chips to use devres to allocate irq descriptors.

   - A bunch of constification fixes"

* tag 'gpio-v4.14-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (63 commits)
  gpio: mockup: remove unused variable gc
  gpio: pl061: constify amba_id
  Revert "gpiolib: request the gpio before querying its direction"
  gpio: twl6040: remove unneeded forward declaration
  gpio: zevio: make gpio_chip const
  gpio: add gpio_add_lookup_tables() to add several tables at once
  gpio: rcar: Add r8a7745 (RZ/G1E) support
  gpio: brcmstb: check return value of gpiochip_irqchip_add()
  MAINTAINERS: Add entry for THUNDERX GPIO Driver.
  gpio: Add gpio driver support for ThunderX and OCTEON-TX
  gpio: mockup: use irq_sim
  gpio: mxs: use devres for irq generic chip
  gpio: mxc: use devres for irq generic chip
  gpio: pch: use devres for irq generic chip
  gpio: ml-ioh: use devres for irq generic chip
  gpio: sta2x11: use devres for irq generic chip
  gpio: sta2x11: disallow unbinding the driver
  gpio: mxs: disallow unbinding the driver
  gpio: mxc: disallow unbinding the driver
  gpio: aspeed: Remove reference to clock name in debounce warning message
  ...

6 years agoMerge tag 'pinctrl-v4.14-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw...
Linus Torvalds [Tue, 5 Sep 2017 18:45:33 +0000 (11:45 -0700)]
Merge tag 'pinctrl-v4.14-1' of git://git./linux/kernel/git/linusw/linux-pinctrl

Pull pin control updates from Linus Walleij:
 "This is the big bulk of pin control changes for the v4.14 kernel.
  There are just a few bigger changes (new drivers mostly) and then a
  lot of small patches all over the place.

  Core changes:
   - Decision to wrap the sleep mode of the Spreadtrum and in the future
     others into a specially tagged state. The generic DT bindings and
     the new Spreadtrum driver conforms to this. Others should be moved
     over if possible.

  New drivers:
   - Spreadtrum SoCs especially the SC9860 SoC.
   - Storlink/Cortina Gemini 3512 and 3516 SoCs.

  New subdrivers:
   - Intel Denverton subdriver.
   - Intel Cannon Lake subdriver.
   - Intel Lewisburg subdriver.
   - Allwinner sunxi: R40 subdriver for A10.
   - Socionext uniphier PXs3 subdriver.
   - Rockchip RK3128 subdriver.
   - Renesas SH-PFC R8A77995 subdriver.

  Miscellaneous:
   - Qualcomm APQ8064 can handle general purpose clock muxing.
   - Mediatek MT7623 PCIe mux data fixed up.
   - Intel GPIO IRQs are disabled during suspend.
   - Several fixes and addtions to Renesas r8a7796.
   - Qualcomm SPMI GPIO supports dtest route and LV/MV subtype.
   - Input schmitt trigger support in Rockchip RV1108.
   - Aspeed G4 and G5 USB host/device pin control control added.
   - Qualcomm IPQ4019 has matured with a few missing pin groups and
     control bits put in place.
   - Lots of constification, this is the latest in cocinelle fixes"

* tag 'pinctrl-v4.14-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl: (147 commits)
  Revert "pinctrl: sunxi: Don't enforce bias disable (for now)"
  pinctrl: uniphier: fix members of rmii group for Pro4
  pinctrl: Delete an error message
  pinctrl: core: Delete an error message
  pinctrl: intel: Read back TX buffer state
  pinctrl: rockchip: Add rv1108 recalculated iomux support
  pinctrl: intel: Decrease indentation in intel_gpio_set()
  pinctrl: rza1: Remove suffix from gpiochip label
  pinctrl: qcom: spmi-gpio: Correct power_source range check
  pinctrl: freescale: make mxs_regs const
  pinctrl: aspeed: Rework strap register write logic for the AST2500
  pinctrl: rza1: off by one in rza1_parse_gpiochip()
  pinctrl: qcom: General Purpose clocks for apq8064
  pinctrl: sprd: Add Spreadtrum pin control driver
  dt-bindings: pinctrl: Add DT bindings for Spreadtrum SC9860
  pinctrl: Add sleep related state to indicate sleep related configs
  pinctrl: mediatek: update PCIe mux data for MT7623
  pinctrl: intel: Add Intel Lewisburg GPIO support
  pinctrl: intel: Add Intel Cannon Lake PCH-H pin controller support
  pinctrl: aspeed: Fix ast2500 strap register write logic
  ...

6 years agoMerge tag 'regulator-v4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie...
Linus Torvalds [Tue, 5 Sep 2017 18:43:30 +0000 (11:43 -0700)]
Merge tag 'regulator-v4.14' of git://git./linux/kernel/git/broonie/regulator

Pull regulator updates from Mark Brown:
 "This is an extremely quiet release for the regulator subsystem, it's
  all fairly minor fixes and cleanups plus a few new drivers and ddevice
  ID additions:

   - Support for MediaTek MT6380, Ricoh RC5T619 and ST Voltage Reference
     Buffers"

* tag 'regulator-v4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator: (24 commits)
  regulator: Add support for stm32-vrefbuf
  regulator: Add STM32 Voltage Reference Buffer
  regulator: pv88090: Exception handling for out of bounds
  regulator: da9063: Return an error code on probe failure
  regulator: rn5t618: add RC5T619 PMIC support
  regulator: ltc3589: constify i2c_device_id
  regulator: fan53555: fix I2C device ids
  regulator: add fixes with MT6397 dt-bindings shouldn't reference driver
  regulator: add fixes with MT6323 dt-bindings shouldn't reference driver
  regulator: add fixes with MT6311 dt-bindings shouldn't reference driver
  regulator: Add document for MediaTek MT6380 regulator
  regulator: mt6380: Add support for MT6380
  regulator: pwm-regulator: Remove unneeded gpiod NULL check
  regulator: core: fix a possible race in disable_work handling
  regulator: fan53555: Use of_device_get_match_data() to simplify probe
  regulator: of: regulator_of_get_init_data() missing of_node_get()
  regulator: pwm-regulator: fix example syntax
  regulator: Convert to using %pOF instead of full_name
  regulator: cpcap: Add OF mode mapping
  regulator: cpcap: Fix standby mode
  ...

6 years agoMerge tag 'spi-v4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi
Linus Torvalds [Tue, 5 Sep 2017 18:40:38 +0000 (11:40 -0700)]
Merge tag 'spi-v4.14' of git://git./linux/kernel/git/broonie/spi

Pull spi updates from Mark Brown:
 "A fairly quiet release for the SPI subsystem:

   - Move to using IDR for allocating bus numbers

   - Modernisation of the ep93xx driver, removing a lot of open coding
     and using the framework more

   - The tools have been moved to use the standard tools build system
     and an install target added (there will be a fairly trivial
     conflict with tip resulting from the changes in the main tools
     Makefile)

   - A refactoring of the Qualcomm QUP driver which enables new variants
     to be supported

   - Explicit support for the Freescale i.MX53 and i.MX6 SPI, Renesas
     R-Car H3 and Rockchip RV1108 controllers"

* tag 'spi-v4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi: (71 commits)
  spi: spi-falcon: drop check of boot select
  spi: imx: fix use of native chip-selects with devicetree
  spi: pl022: constify amba_id
  spi: imx: fix little-endian build
  spi: omap: Allocate bus number from spi framework
  spi: Kernel coding style fixes
  spi: imx: dynamic burst length adjust for PIO mode
  spi: Pick spi bus number from Linux idr or spi alias
  spi: rockchip: configure CTRLR1 according to size and data frame
  spi: altera: Consolidate TX/RX data register access
  spi: altera: Switch to SPI core transfer queue management
  spi: rockchip: add compatible string for rv1108 spi
  spi: qup: fix 64-bit build warning
  spi: qup: hide warning for uninitialized variable
  spi: spi-ep93xx: use the default master transfer queueing mechanism
  spi: spi-ep93xx: remove private data 'current_msg'
  spi: spi-ep93xx: pass the spi_master pointer around
  spi: spi-ep93xx: absorb the interrupt enable/disable helpers
  spi: spi-ep93xx: add spi master prepare_transfer_hardware()
  spi: spi-ep93xx: use 32-bit read/write for all registers
  ...

6 years agoMerge tag 'edac_for_4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/bp/bp
Linus Torvalds [Tue, 5 Sep 2017 18:35:16 +0000 (11:35 -0700)]
Merge tag 'edac_for_4.14' of git://git./linux/kernel/git/bp/bp

Pull EDAC updates from Borislav Petkov:

 - pnd2_edac: A minimal sideband driver (Tony Luck)

 - small-ish cleanups and fixes all over the place

* tag 'edac_for_4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/bp/bp:
  EDAC, mce_amd: Get rid of local var in amd_filter_mce()
  EDAC, mce_amd: Get rid of most struct cpuinfo_x86 uses
  EDAC, mce_amd: Rename decode_smca_errors() to decode_smca_error()
  EDAC: Make device_type const
  EDAC, pnd2: Properly toggle hidden state for P2SB PCI device
  EDAC, pnd2: Conditionally unhide/hide the P2SB PCI device to read BAR
  EDAC, pnd2: Mask off the lower four bits of a BAR
  EDAC, thunderx: Fix error handling path in thunderx_lmc_probe()
  EDAC, altera: Fix error handling path in altr_edac_device_probe()
  EDAC, pnd2: Build in a minimal sideband driver for Apollo Lake
  EDAC, sb_edac: Classify memory mirroring modes
  EDAC, cpc925, ppc4xx: Convert to using %pOF instead of full_name
  EDAC: Get rid of mci->mod_ver
  EDAC: Constify attribute_group structures
  EDAC, mce_amd: Use cpu_to_node() to find the node ID

6 years agoMerge tag 'char-misc-4.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregk...
Linus Torvalds [Tue, 5 Sep 2017 18:08:17 +0000 (11:08 -0700)]
Merge tag 'char-misc-4.14-rc1' of git://git./linux/kernel/git/gregkh/char-misc

Pull char/misc driver updates from Greg KH:
 "Here is the big char/misc driver update for 4.14-rc1.

  Lots of different stuff in here, it's been an active development cycle
  for some reason. Highlights are:

   - updated binder driver, this brings binder up to date with what
     shipped in the Android O release, plus some more changes that
     happened since then that are in the Android development trees.

   - coresight updates and fixes

   - mux driver file renames to be a bit "nicer"

   - intel_th driver updates

   - normal set of hyper-v updates and changes

   - small fpga subsystem and driver updates

   - lots of const code changes all over the driver trees

   - extcon driver updates

   - fmc driver subsystem upadates

   - w1 subsystem minor reworks and new features and drivers added

   - spmi driver updates

  Plus a smattering of other minor driver updates and fixes.

  All of these have been in linux-next with no reported issues for a
  while"

* tag 'char-misc-4.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (244 commits)
  ANDROID: binder: don't queue async transactions to thread.
  ANDROID: binder: don't enqueue death notifications to thread todo.
  ANDROID: binder: Don't BUG_ON(!spin_is_locked()).
  ANDROID: binder: Add BINDER_GET_NODE_DEBUG_INFO ioctl
  ANDROID: binder: push new transactions to waiting threads.
  ANDROID: binder: remove proc waitqueue
  android: binder: Add page usage in binder stats
  android: binder: fixup crash introduced by moving buffer hdr
  drivers: w1: add hwmon temp support for w1_therm
  drivers: w1: refactor w1_slave_show to make the temp reading functionality separate
  drivers: w1: add hwmon support structures
  eeprom: idt_89hpesx: Support both ACPI and OF probing
  mcb: Fix an error handling path in 'chameleon_parse_cells()'
  MCB: add support for SC31 to mcb-lpc
  mux: make device_type const
  char: virtio: constify attribute_group structures.
  Documentation/ABI: document the nvmem sysfs files
  lkdtm: fix spelling mistake: "incremeted" -> "incremented"
  perf: cs-etm: Fix ETMv4 CONFIGR entry in perf.data file
  nvmem: include linux/err.h from header
  ...