sfrench/cifs-2.6.git
4 months agoposix-cpu-timers: Move state tracking to struct posix_cputimers
Thomas Gleixner [Wed, 21 Aug 2019 19:09:24 +0000 (21:09 +0200)]
posix-cpu-timers: Move state tracking to struct posix_cputimers

Put it where it belongs and clean up the ifdeffery in fork completely.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190821192922.743229404@linutronix.de
4 months agoposix-cpu-timers: Deduplicate rlimit handling
Thomas Gleixner [Wed, 21 Aug 2019 19:09:23 +0000 (21:09 +0200)]
posix-cpu-timers: Deduplicate rlimit handling

Both thread and process expiry functions have the same functionality for
sending signals for soft and hard RLIMITs duplicated in 4 different
ways.

Split it out into a common function and cleanup the callsites.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192922.653276779@linutronix.de
4 months agoposix-cpu-timers: Remove pointless comparisons
Thomas Gleixner [Wed, 21 Aug 2019 19:09:22 +0000 (21:09 +0200)]
posix-cpu-timers: Remove pointless comparisons

The soft RLIMIT expiry code checks whether the soft limit is greater than
the hard limit. That's pointless because if the soft RLIMIT is greater than
the hard RLIMIT then that code cannot be reached as the hard RLIMIT check
is before that and already killed the process.

Remove it.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192922.548747613@linutronix.de
4 months agoposix-cpu-timers: Get rid of 64bit divisions
Thomas Gleixner [Wed, 21 Aug 2019 19:09:21 +0000 (21:09 +0200)]
posix-cpu-timers: Get rid of 64bit divisions

Instead of dividing A to match the units of B it's more efficient to
multiply B to match the units of A.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192922.458286860@linutronix.de
4 months agoposix-cpu-timers: Consolidate timer expiry further
Thomas Gleixner [Wed, 21 Aug 2019 19:09:20 +0000 (21:09 +0200)]
posix-cpu-timers: Consolidate timer expiry further

With the array based samples and expiry cache, the expiry function can use
a loop to collect timers from the clock specific lists.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192922.365469982@linutronix.de
4 months agoposix-cpu-timers: Get rid of zero checks
Thomas Gleixner [Wed, 21 Aug 2019 19:09:19 +0000 (21:09 +0200)]
posix-cpu-timers: Get rid of zero checks

Deactivation of the expiry cache is done by setting all clock caches to
0. That requires to have a check for zero in all places which update the
expiry cache:

if (cache == 0 || new < cache)
cache = new;

Use U64_MAX as the deactivated value, which allows to remove the zero
checks when updating the cache and reduces it to the obvious check:

if (new < cache)
cache = new;

This also removes the weird workaround in do_prlimit() which was required
to convert a RLIMIT_CPU value of 0 (immediate expiry) to 1 because handing
in 0 to the posix CPU timer code would have effectively disarmed it.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192922.275086128@linutronix.de
4 months agorlimit: Rewrite non-sensical RLIMIT_CPU comment
Thomas Gleixner [Wed, 21 Aug 2019 19:09:18 +0000 (21:09 +0200)]
rlimit: Rewrite non-sensical RLIMIT_CPU comment

The comment above the function which arms RLIMIT_CPU in the posix CPU timer
code makes no sense at all. It claims that the kernel does not return an
error code when it rejected the attempt to set RLIMIT_CPU. That's clearly
bogus as the code does an error check and the rlimit is only set and
activated when the permission checks are ok. In case of a rejection an
appropriate error code is returned.

This is a historical and outdated comment which got dragged along even when
the rlimit handling code was rewritten.

Replace it with an explanation why the setup function is not called when
the rlimit value is RLIM_INFINITY and how the 'disarming' is handled.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192922.185511287@linutronix.de
4 months agoposix-cpu-timers: Respect INFINITY for hard RTTIME limit
Thomas Gleixner [Wed, 21 Aug 2019 19:09:17 +0000 (21:09 +0200)]
posix-cpu-timers: Respect INFINITY for hard RTTIME limit

The RTIME limit expiry code does not check the hard RTTIME limit for
INFINITY, i.e. being disabled.  Add it.

While this could be considered an ABI breakage if something would depend on
this behaviour. Though it's highly unlikely to have an effect because
RLIM_INFINITY is at minimum INT_MAX and the RTTIME limit is in seconds, so
the timer would fire after ~68 years.

Adding this obvious correct limit check also allows further consolidation
of that code and is a prerequisite for cleaning up the 0 based checks and
the rlimit setter code.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192922.078293002@linutronix.de
4 months agoposix-cpu-timers: Switch thread group sampling to array
Thomas Gleixner [Wed, 21 Aug 2019 19:09:16 +0000 (21:09 +0200)]
posix-cpu-timers: Switch thread group sampling to array

That allows more simplifications in various places.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192921.988426956@linutronix.de
4 months agoposix-cpu-timers: Restructure expiry array
Thomas Gleixner [Mon, 26 Aug 2019 18:22:24 +0000 (20:22 +0200)]
posix-cpu-timers: Restructure expiry array

Now that the abused struct task_cputime is gone, it's more natural to
bundle the expiry cache and the list head of each clock into a struct and
have an array of those structs.

Follow the hrtimer naming convention of 'bases' and rename the expiry cache
to 'nextevt' and adapt all usage sites.

Generates also better code .text size shrinks by 80 bytes.

Suggested-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/alpine.DEB.2.21.1908262021140.1939@nanos.tec.linutronix.de
4 months agoposix-cpu-timers: Remove cputime_expires
Thomas Gleixner [Wed, 21 Aug 2019 19:09:14 +0000 (21:09 +0200)]
posix-cpu-timers: Remove cputime_expires

The last users of the magic struct cputime based expiry cache are
gone. Remove the leftovers.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192921.790209622@linutronix.de
4 months agoposix-cpu-timers: Make expiry checks array based
Thomas Gleixner [Wed, 21 Aug 2019 19:09:13 +0000 (21:09 +0200)]
posix-cpu-timers: Make expiry checks array based

The expiry cache is an array indexed by clock ids. The new sample functions
allow to retrieve a corresponding array of samples.

Convert the fastpath expiry checks to make use of the new sample functions
and do the comparisons on the sample and the expiry array.

Make the check for the expiry array being zero array based as well.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192921.695481430@linutronix.de
4 months agoposix-cpu-timers: Provide array based sample functions
Thomas Gleixner [Wed, 21 Aug 2019 19:09:12 +0000 (21:09 +0200)]
posix-cpu-timers: Provide array based sample functions

Instead of using task_cputime and doing the addition of utime and stime at
all call sites, it's way simpler to have a sample array which allows
indexed based checks against the expiry cache array.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192921.590362974@linutronix.de
4 months agoposix-cpu-timers: Remove the odd field rename defines
Thomas Gleixner [Wed, 21 Aug 2019 19:09:11 +0000 (21:09 +0200)]
posix-cpu-timers: Remove the odd field rename defines

The last users of the odd define based renaming of struct task_cputime
members are gone. Good riddance.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192921.499058279@linutronix.de
4 months agoposix-cpu-timers: Switch check_*_timers() to array cache
Thomas Gleixner [Wed, 21 Aug 2019 19:09:10 +0000 (21:09 +0200)]
posix-cpu-timers: Switch check_*_timers() to array cache

Use the array based expiry cache in check_thread_timers() and convert the
store in check_process_timers() for consistency.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192921.408222378@linutronix.de
4 months agoposix-cpu-timers: Simplify set_process_cpu_timer()
Thomas Gleixner [Wed, 21 Aug 2019 19:09:09 +0000 (21:09 +0200)]
posix-cpu-timers: Simplify set_process_cpu_timer()

The expiry cache can now be accessed as an array. Replace the per clock
checks with a simple comparison of the clock indexed array member.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192921.303316423@linutronix.de
4 months agoposix-cpu-timers: Simplify timer queueing
Thomas Gleixner [Wed, 21 Aug 2019 19:09:08 +0000 (21:09 +0200)]
posix-cpu-timers: Simplify timer queueing

Now that the expiry cache can be accessed as an array, the per clock
checking can be reduced to just comparing the corresponding array elements.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192921.212129449@linutronix.de
4 months agoposix-cpu-timers: Provide array based access to expiry cache
Thomas Gleixner [Wed, 21 Aug 2019 19:09:07 +0000 (21:09 +0200)]
posix-cpu-timers: Provide array based access to expiry cache

Using struct task_cputime for the expiry cache is a pretty odd choice and
comes with magic defines to rename the fields for usage in the expiry
cache.

struct task_cputime is basically a u64 array with 3 members, but it has
distinct members.

The expiry cache content is different than the content of task_cputime
because

  expiry[PROF]  = task_cputime.stime + task_cputime.utime
  expiry[VIRT]  = task_cputime.utime
  expiry[SCHED] = task_cputime.sum_exec_runtime

So there is no direct mapping between task_cputime and the expiry cache and
the #define based remapping is just a horrible hack.

Having the expiry cache array based allows further simplification of the
expiry code.

To avoid an all in one cleanup which is hard to review add a temporary
anonymous union into struct task_cputime which allows array based access to
it. That requires to reorder the members. Add a build time sanity check to
validate that the members are at the same place.

The union and the build time checks will be removed after conversion.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192921.105793824@linutronix.de
4 months agoposix-cpu-timers: Move expiry cache into struct posix_cputimers
Thomas Gleixner [Wed, 21 Aug 2019 19:09:06 +0000 (21:09 +0200)]
posix-cpu-timers: Move expiry cache into struct posix_cputimers

The expiry cache belongs into the posix_cputimers container where the other
cpu timers information is.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192921.014444012@linutronix.de
4 months agosched: Move struct task_cputime to types.h
Thomas Gleixner [Wed, 21 Aug 2019 19:09:05 +0000 (21:09 +0200)]
sched: Move struct task_cputime to types.h

For upcoming posix-timer changes to avoid include recursion hell.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190821192920.909530418@linutronix.de
4 months agoposix-cpu-timers: Create a container struct
Thomas Gleixner [Wed, 21 Aug 2019 19:09:04 +0000 (21:09 +0200)]
posix-cpu-timers: Create a container struct

Per task/process data of posix CPU timers is all over the place which
makes the code hard to follow and requires ifdeffery.

Create a container to hold all this information in one place, so data is
consolidated and the ifdeffery can be confined to the posix timer header
file and removed from places like fork.

As a first step, move the cpu_timers list head array into the new struct
and clean up the initializers and simplify fork. The remaining #ifdef in
fork will be removed later.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192920.819418976@linutronix.de
4 months agoposix-cpu-timers: Move prof/virt_ticks into caller
Thomas Gleixner [Wed, 21 Aug 2019 19:09:03 +0000 (21:09 +0200)]
posix-cpu-timers: Move prof/virt_ticks into caller

The functions have only one caller left. No point in having them.

Move the almost duplicated code into the caller and simplify it.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192920.729298382@linutronix.de
4 months agoposix-cpu-timers: Sample task times once in expiry check
Thomas Gleixner [Wed, 21 Aug 2019 19:09:02 +0000 (21:09 +0200)]
posix-cpu-timers: Sample task times once in expiry check

Sampling the task times twice does not make sense. Do it once.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192920.639878168@linutronix.de
4 months agoposix-cpu-timers: Get rid of pointer indirection
Thomas Gleixner [Wed, 21 Aug 2019 19:09:01 +0000 (21:09 +0200)]
posix-cpu-timers: Get rid of pointer indirection

Now that the sample functions have no return value anymore, the result can
simply be returned instead of using pointer indirection.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192920.535079278@linutronix.de
4 months agoposix-cpu-timers: Simplify sample functions
Thomas Gleixner [Wed, 21 Aug 2019 19:09:00 +0000 (21:09 +0200)]
posix-cpu-timers: Simplify sample functions

All callers hand in a valdiated clock id. Remove the return value which was
unchecked in most places anyway.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192920.430475832@linutronix.de
4 months agoposix-cpu-timers: Remove pointless return value check
Thomas Gleixner [Wed, 21 Aug 2019 19:08:59 +0000 (21:08 +0200)]
posix-cpu-timers: Remove pointless return value check

set_process_cpu_timer() checks already whether the clock id is valid. No
point in checking the return value of the sample function. That allows to
simplify the sample function later.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192920.339725769@linutronix.de
4 months agoposix-cpu-timers: Use clock ID in posix_cpu_timer_rearm()
Thomas Gleixner [Wed, 21 Aug 2019 19:08:58 +0000 (21:08 +0200)]
posix-cpu-timers: Use clock ID in posix_cpu_timer_rearm()

Extract the clock ID (PROF/VIRT/SCHED) from the clock selector and use it
as argument to the sample functions. That allows to simplify them once all
callers are fixed.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192920.245357769@linutronix.de
4 months agoposix-cpu-timers: Use clock ID in posix_cpu_timer_get()
Thomas Gleixner [Wed, 21 Aug 2019 19:08:57 +0000 (21:08 +0200)]
posix-cpu-timers: Use clock ID in posix_cpu_timer_get()

Extract the clock ID (PROF/VIRT/SCHED) from the clock selector and use it
as argument to the sample functions. That allows to simplify them once all
callers are fixed.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192920.155487201@linutronix.de
4 months agoposix-cpu-timers: Use clock ID in posix_cpu_timer_set()
Thomas Gleixner [Wed, 21 Aug 2019 19:08:56 +0000 (21:08 +0200)]
posix-cpu-timers: Use clock ID in posix_cpu_timer_set()

Extract the clock ID (PROF/VIRT/SCHED) from the clock selector and use it
as argument to the sample functions. That allows to simplify them once all
callers are fixed.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192920.050770464@linutronix.de
4 months agoposix-cpu-timers: Consolidate thread group sample code
Thomas Gleixner [Wed, 21 Aug 2019 19:08:55 +0000 (21:08 +0200)]
posix-cpu-timers: Consolidate thread group sample code

cpu_clock_sample_group() and cpu_timer_sample_group() are almost the
same. Before the rename one called thread_group_cputimer() and the other
thread_group_cputime(). Really intuitive function names.

Consolidate the functions and also avoid the thread traversal when
the thread group's accounting is already active.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192919.960966884@linutronix.de
4 months agoposix-cpu-timers: Rename thread_group_cputimer() and make it static
Thomas Gleixner [Wed, 21 Aug 2019 19:08:54 +0000 (21:08 +0200)]
posix-cpu-timers: Rename thread_group_cputimer() and make it static

thread_group_cputimer() is a complete misnomer. The function does two things:

 - For arming process wide timers it makes sure that the atomic time
   storage is up to date. If no cpu timer is armed yet, then the atomic
   time storage is not updated by the scheduler for performance reasons.

   In that case a full summing up of all threads needs to be done and the
   update needs to be enabled.

- Samples the current time into the caller supplied storage.

Rename it to thread_group_start_cputime(), make it static and fixup the
callsite.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192919.869350319@linutronix.de
4 months agoposix-cpu-timers: Sample directly in timer check
Thomas Gleixner [Wed, 21 Aug 2019 19:08:53 +0000 (21:08 +0200)]
posix-cpu-timers: Sample directly in timer check

The thread group accounting is active, otherwise the expiry function would
not be running. Sample the thread group time directly.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192919.780348088@linutronix.de
4 months agoitimers: Use quick sample function
Thomas Gleixner [Wed, 21 Aug 2019 19:08:52 +0000 (21:08 +0200)]
itimers: Use quick sample function

get_itimer() locks sighand lock and checks whether the timer is already
expired. If it is not expired then the thread group cputime accounting is
already enabled. Use the sampling function not the one which is meant for
starting a timer.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192919.689713638@linutronix.de
4 months agoposix-cpu-timers: Provide quick sample function for itimer
Thomas Gleixner [Wed, 21 Aug 2019 19:08:51 +0000 (21:08 +0200)]
posix-cpu-timers: Provide quick sample function for itimer

get_itimer() needs a sample of the current thread group cputime. It invokes
thread_group_cputimer() - which is a misnomer. That function also starts
eventually the group cputime accouting which is bogus because the
accounting is already active when a timer is armed.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192919.599658199@linutronix.de
4 months agoposix-cpu-timers: Use common permission check in posix_cpu_timer_create()
Thomas Gleixner [Wed, 21 Aug 2019 19:08:50 +0000 (21:08 +0200)]
posix-cpu-timers: Use common permission check in posix_cpu_timer_create()

Yet another copy of the same thing gone...

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192919.505833418@linutronix.de
4 months agoposix-cpu-timers: Use common permission check in posix_cpu_clock_get()
Thomas Gleixner [Wed, 21 Aug 2019 19:08:49 +0000 (21:08 +0200)]
posix-cpu-timers: Use common permission check in posix_cpu_clock_get()

Replace the next slightly different copy of permission checks. That also
removes the necessarity to check the return value of the sample functions
because the clock id is already validated.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192919.414813172@linutronix.de
4 months agoposix-cpu-timers: Provide task validation functions
Thomas Gleixner [Wed, 21 Aug 2019 19:08:48 +0000 (21:08 +0200)]
posix-cpu-timers: Provide task validation functions

The code contains three slightly different copies of validating whether a
given clock resolves to a valid task and whether the current caller has
permissions to access it.

Create central functions. Replace check_clock() as a first step and rename
it to something sensible.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190821192919.326097175@linutronix.de
4 months agoMerge tag 'timers-v5.4' of https://git.linaro.org/people/daniel.lezcano/linux into...
Thomas Gleixner [Mon, 26 Aug 2019 22:42:06 +0000 (00:42 +0200)]
Merge tag 'timers-v5.4' of https://git.linaro.org/people/daniel.lezcano/linux into timers/core

Pull clocksource/events updates from Daniel Lezcano:

 - Remove dev_err() when used with platform_get_irq (Stephen Boyd)

 - Add DT binding and new compatible for Allwinner sun4i (Maxime Ripard)

 - Register the Atmel tcb clocksource for delays (Alexandre Belloni)

 - Add a clock divider for the Freescale imx platforms and new timer node
   in the DT (Anson Huang)

 - Use DIV_ROUND_CLOSEST macro for the Renesas OSTM (Geert Uytterhoeven)

 - Fix GENMASK and timer operation for the npcm timer (Avi Fishman)

 - Fix timer-of showing an error message when EPROBE_DEFER is
   returned (Jon Hunter)

 - Add new SoC DT binding and match for Renesas timers (Magnus Damm)

4 months agoclocksource/drivers/sh_cmt: Document "cmt-48" as deprecated
Magnus Damm [Tue, 20 Aug 2019 12:36:07 +0000 (21:36 +0900)]
clocksource/drivers/sh_cmt: Document "cmt-48" as deprecated

Update the CMT driver to mark "renesas,cmt-48" as deprecated.

Instead of documenting a theoretical hardware device based on current software
support level, define DT bindings top-down based on available data sheet
information and make use of part numbers in the DT compat string.

In case of the only in-tree users r8a7740 and sh73a0 the compat strings
"renesas,r8a7740-cmt1" and "renesas,sh73a0-cmt1" may be used instead.

Signed-off-by: Magnus Damm <damm+renesas@opensource.se>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
4 months agoclocksource/drivers/sh_cmt: r8a7740 and sh73a0 SoC-specific match
Magnus Damm [Tue, 20 Aug 2019 12:35:56 +0000 (21:35 +0900)]
clocksource/drivers/sh_cmt: r8a7740 and sh73a0 SoC-specific match

Add SoC-specific matching for CMT1 on r8a7740 and sh73a0.

This allows us to move away from the old DT bindings such as
 - "renesas,cmt-48-sh73a0"
 - "renesas,cmt-48-r8a7740"
 - "renesas,cmt-48"
in favour for the now commonly used format "renesas,<soc>-<device>"

Signed-off-by: Magnus Damm <damm+renesas@opensource.se>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
4 months agodt-bindings: timer: renesas, cmt: Update R-Car Gen3 CMT1 usage
Magnus Damm [Tue, 20 Aug 2019 12:35:46 +0000 (21:35 +0900)]
dt-bindings: timer: renesas, cmt: Update R-Car Gen3 CMT1 usage

The R-Car Gen3 SoCs so far come with a total for 4 on-chip CMT devices:
 - CMT0
 - CMT1
 - CMT2
 - CMT3

CMT0 includes two rather basic 32-bit timer channels. The rest of the on-chip
CMT devices support 48-bit counters and have 8 channels each.

Based on the data sheet information "CMT2/3 are exactly same as CMT1"
it seems that CMT2 and CMT3 now use the CMT1 compat string in the DTSI.

Clarify this in the DT binding documentation by describing R-Car Gen3 and
RZ/G2 CMT1 as "48-bit CMT devices".

Signed-off-by: Magnus Damm <damm+renesas@opensource.se>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Rob Herring <robh@kernel.org>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
4 months agodt-bindings: timer: renesas, cmt: Add CMT0 and CMT1 to r8a77995
Magnus Damm [Tue, 20 Aug 2019 12:35:36 +0000 (21:35 +0900)]
dt-bindings: timer: renesas, cmt: Add CMT0 and CMT1 to r8a77995

This patch adds DT binding documentation for the CMT devices on
the R-Car Gen3 D3 (r8a77995) SoC.

Signed-off-by: Magnus Damm <damm+renesas@opensource.se>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Rob Herring <robh@kernel.org>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
4 months agodt-bindings: timer: renesas, cmt: Add CMT0 and CMT1 to r8a7792
Magnus Damm [Tue, 20 Aug 2019 12:35:25 +0000 (21:35 +0900)]
dt-bindings: timer: renesas, cmt: Add CMT0 and CMT1 to r8a7792

This patch adds DT binding documentation for the CMT devices on
the R-Car Gen2 V2H (r8a7792) SoC.

Signed-off-by: Magnus Damm <damm+renesas@opensource.se>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Rob Herring <robh@kernel.org>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
4 months agodt-bindings: timer: renesas, cmt: Update CMT1 on sh73a0 and r8a7740
Magnus Damm [Tue, 20 Aug 2019 12:35:14 +0000 (21:35 +0900)]
dt-bindings: timer: renesas, cmt: Update CMT1 on sh73a0 and r8a7740

This patch reworks the DT binding documentation for the 6-channel
48-bit CMTs known as CMT1 on r8a7740 and sh73a0.

After the update the same style of DT binding as the rest of the upstream
SoCs will now also be used by r8a7740 and sh73a0. The DT binding "cmt-48"
is removed from the DT binding documentation, however software support for
this deprecated binding will still remain in the CMT driver for some time.

Signed-off-by: Magnus Damm <damm+renesas@opensource.se>
Reviewed-by: Rob Herring <robh@kernel.org>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
4 months agodt-bindings: timer: renesas, cmt: Add CMT0234 to sh73a0 and r8a7740
Magnus Damm [Tue, 20 Aug 2019 12:35:03 +0000 (21:35 +0900)]
dt-bindings: timer: renesas, cmt: Add CMT0234 to sh73a0 and r8a7740

Document the on-chip CMT devices included in r8a7740 and sh73a0.

Included in this patch is DT binding documentation for 32-bit CMTs
CMT0, CMT2, CMT3 and CMT4. They all contain a single channel and are
quite similar however some minor differences still exist:
 - "Counter input clock" (clock input and on-device divider)
    One example is that RCLK 1/1 is supported by CMT2, CMT3 and CMT4.
 - "Wakeup request" (supported by CMT0 and CMT2)

Because of this one unique compat string per CMT device is selected.

Signed-off-by: Magnus Damm <damm+renesas@opensource.se>
Reviewed-by: Rob Herring <robh@kernel.org>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
4 months agoclocksource/drivers: Do not warn on probe defer
Jon Hunter [Wed, 21 Aug 2019 15:02:41 +0000 (16:02 +0100)]
clocksource/drivers: Do not warn on probe defer

Deferred probe is an expected return value on many platforms and so
there's no need to output a warning that may potentially confuse users.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
4 months agoclocksource/drivers/timer-of: Do not warn on deferred probe
Jon Hunter [Wed, 21 Aug 2019 15:02:40 +0000 (16:02 +0100)]
clocksource/drivers/timer-of: Do not warn on deferred probe

Deferred probe is an expected return value for clk_get() on many
platforms. The driver deals with it properly, so there's no need
to output a warning that may potentially confuse users.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
4 months agoclocksource/drivers/npcm: Fix GENMASK and timer operation
Avi Fishman [Mon, 29 Jul 2019 17:03:54 +0000 (20:03 +0300)]
clocksource/drivers/npcm: Fix GENMASK and timer operation

NPCM7XX_Tx_OPER GENMASK bits are wrong, fix them.

Hopefully the NPCM7XX_REG_TICR0 register reset value of those bits was 0,
so it did not cause an issue.

The function npcm7xx_timer_oneshot() reads the register
NPCM7XX_REG_TCSR0, modifies it and then reads it again overwriting the
previous changes. Remove the extra read which is pointless.

The function npcm7xx_timer_periodic() is correct but the code writes
to the NPCM7XX_REG_TICR0 register while it is dealing with the
NPCM7XX_REG_TCSR0 register, that is confusing. Separate the write to
the registers in the code for the sake of clarity.

Fixes: 1c00289ecd12 ("clocksource/drivers/npcm: Add NPCM7xx timer driver")
Signed-off-by: Avi Fishman <avifishman70@gmail.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
4 months agoclocksource/drivers/renesas-ostm: Use DIV_ROUND_CLOSEST() helper
Geert Uytterhoeven [Wed, 7 Aug 2019 08:46:33 +0000 (10:46 +0200)]
clocksource/drivers/renesas-ostm: Use DIV_ROUND_CLOSEST() helper

Use the DIV_ROUND_CLOSEST() helper instead of open-coding the same
operation.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
4 months agoarm64: dts: imx8mq: Add system counter node
Anson Huang [Fri, 16 Aug 2019 00:38:44 +0000 (20:38 -0400)]
arm64: dts: imx8mq: Add system counter node

Add i.MX8MQ system counter node to enable timer-imx-sysctr
broadcast timer driver.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
4 months agoarm64: dts: imx8mm: Add system counter node
Anson Huang [Fri, 16 Aug 2019 00:38:43 +0000 (20:38 -0400)]
arm64: dts: imx8mm: Add system counter node

Add i.MX8MM system counter node to enable timer-imx-sysctr
broadcast timer driver.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
4 months agoclocksource/drivers/imx-sysctr: Add internal clock divider handle
Anson Huang [Fri, 16 Aug 2019 00:38:42 +0000 (20:38 -0400)]
clocksource/drivers/imx-sysctr: Add internal clock divider handle

The system counter block guide states that the base clock is
internally divided by 3 before use, that means the clock input of
system counter defined in DT should be base clock which is normally
from OSC, and then internally divided by 3 before use.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
4 months agoclocksource/drivers/tcb_clksrc: Register delay timer
Alexandre Belloni [Tue, 13 Aug 2019 13:30:50 +0000 (15:30 +0200)]
clocksource/drivers/tcb_clksrc: Register delay timer

Implement and register delay timer to allow get_cycles() to work properly.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
4 months agodt-bindings: timer: Convert Allwinner A13 HSTimer to a schema
Maxime Ripard [Mon, 22 Jul 2019 08:12:22 +0000 (10:12 +0200)]
dt-bindings: timer: Convert Allwinner A13 HSTimer to a schema

The newer Allwinner SoCs have a High Speed Timer supported in Linux, with a
matching Device Tree binding.

Now that we have the DT validation in place, let's convert the device tree
bindings for that controller over to a YAML schemas.

Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
4 months agoclocksource: sun4i: Add missing compatibles
Maxime Ripard [Mon, 22 Jul 2019 08:12:21 +0000 (10:12 +0200)]
clocksource: sun4i: Add missing compatibles

Newer Allwinner SoCs have different number of interrupts, let's add
different compatibles for all of them to deal with this properly.

Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
4 months agodt-bindings: timer: Add missing compatibles
Maxime Ripard [Mon, 22 Jul 2019 08:12:20 +0000 (10:12 +0200)]
dt-bindings: timer: Add missing compatibles

Newer Allwinner SoCs have different number of interrupts, let's add
different compatibles for all of them to deal with this properly.

Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
4 months agodt-bindings: timer: Convert Allwinner A10 Timer to a schema
Maxime Ripard [Mon, 22 Jul 2019 08:12:19 +0000 (10:12 +0200)]
dt-bindings: timer: Convert Allwinner A10 Timer to a schema

The older Allwinner SoCs have a Timer supported in Linux, with a matching
Device Tree binding.

While the original binding only mentions one interrupt, the timer actually
has 6 of them.

Now that we have the DT validation in place, let's convert the device tree
bindings for that controller over to a YAML schemas.

Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
4 months agoclocksource: Remove dev_err() usage after platform_get_irq()
Stephen Boyd [Tue, 30 Jul 2019 18:15:04 +0000 (11:15 -0700)]
clocksource: Remove dev_err() usage after platform_get_irq()

We don't need dev_err() messages when platform_get_irq() fails now that
platform_get_irq() prints an error message itself when something goes
wrong. Let's remove these prints with a simple semantic patch.

// <smpl>
@@
expression ret;
struct platform_device *E;
@@

ret =
(
platform_get_irq(E, ...)
|
platform_get_irq_byname(E, ...)
);

if ( \( ret < 0 \| ret <= 0 \) )
{
(
-if (ret != -EPROBE_DEFER)
-{ ...
-dev_err(...);
-... }
|
...
-dev_err(...);
)
...
}
// </smpl>

While we're here, remove braces on if statements that only have one
statement (manually).

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
5 months agoclocksource/drivers/hyperv: Enable TSC page clocksource on 32bit
Vitaly Kuznetsov [Thu, 22 Aug 2019 08:36:30 +0000 (10:36 +0200)]
clocksource/drivers/hyperv: Enable TSC page clocksource on 32bit

There is no particular reason to not enable TSC page clocksource on
32-bit. mul_u64_u64_shr() is available and despite the increased
computational complexity (compared to 64bit) TSC page is still a huge win
compared to MSR-based clocksource.

In-kernel reads:
  MSR based clocksource: 3361 cycles
  TSC page clocksource: 49 cycles

Reads from userspace (utilizing vDSO in case of TSC page):
  MSR based clocksource: 5664 cycles
  TSC page clocksource: 131 cycles

Enabling TSC page on 32bits allows to get rid of CONFIG_HYPERV_TSCPAGE as
it is now not any different from CONFIG_HYPERV_TIMER.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Link: https://lkml.kernel.org/r/20190822083630.17059-1-vkuznets@redhat.com
5 months agoclocksource/drivers/hyperv: Add Hyper-V specific sched clock function
Tianyu Lan [Wed, 14 Aug 2019 12:32:16 +0000 (20:32 +0800)]
clocksource/drivers/hyperv: Add Hyper-V specific sched clock function

Hyper-V guests use the default native_sched_clock() in
pv_ops.time.sched_clock on x86. But native_sched_clock() directly uses the
raw TSC value, which can be discontinuous in a Hyper-V VM.

Add the generic hv_setup_sched_clock() to set the sched clock function
appropriately. On x86, this sets pv_ops.time.sched_clock to read the
Hyper-V reference TSC value that is scaled and adjusted to be continuous.

Also move the Hyper-V reference TSC initialization much earlier in the boot
process so no discontinuity is observed when pv_ops.time.sched_clock
calculates its offset.

[ tglx: Folded build fix ]

Signed-off-by: Tianyu Lan <Tianyu.Lan@microsoft.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Link: https://lkml.kernel.org/r/20190814123216.32245-3-Tianyu.Lan@microsoft.com
5 months agoclocksource/drivers/hyperv: Allocate Hyper-V TSC page statically
Tianyu Lan [Wed, 14 Aug 2019 12:32:15 +0000 (20:32 +0800)]
clocksource/drivers/hyperv: Allocate Hyper-V TSC page statically

Prepare to add Hyper-V sched clock callback and move Hyper-V Reference TSC
initialization much earlier in the boot process.  Earlier initialization is
needed so that it happens while the timestamp value is still 0 and no
discontinuity in the timestamp will occur when pv_ops.time.sched_clock
calculates its offset.

The earlier initialization requires that the Hyper-V TSC page be allocated
statically instead of with vmalloc(), so fixup the references to the TSC
page and the method of getting its physical address.

Signed-off-by: Tianyu Lan <Tianyu.Lan@microsoft.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lkml.kernel.org/r/20190814123216.32245-2-Tianyu.Lan@microsoft.com
5 months agoposix-cpu-timers: Remove tsk argument from run_posix_cpu_timers()
Thomas Gleixner [Mon, 19 Aug 2019 14:31:47 +0000 (16:31 +0200)]
posix-cpu-timers: Remove tsk argument from run_posix_cpu_timers()

It's always current. Don't give people wrong ideas.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190819143801.945469967@linutronix.de
5 months agoposix-cpu-timers: Sanitize bogus WARNONS
Thomas Gleixner [Mon, 19 Aug 2019 14:31:46 +0000 (16:31 +0200)]
posix-cpu-timers: Sanitize bogus WARNONS

Warning when p == NULL and then proceeding and dereferencing p does not
make any sense as the kernel will crash with a NULL pointer dereference
right away.

Bailing out when p == NULL and returning an error code does not cure the
underlying problem which caused p to be NULL. Though it might allow to
do proper debugging.

Same applies to the clock id check in set_process_cpu_timer().

Clean them up and make them return without trying to do further damage.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190819143801.846497772@linutronix.de
5 months agohrtimer: Don't take expiry_lock when timer is currently migrated
Julien Grall [Wed, 21 Aug 2019 09:24:09 +0000 (10:24 +0100)]
hrtimer: Don't take expiry_lock when timer is currently migrated

migration_base is used as a placeholder when an hrtimer is migrated to a
different CPU. In the case that hrtimer_cancel_wait_running() hits a timer
which is currently migrated it would pointlessly acquire the expiry lock of
the migration base, which is even not initialized.

Surely it could be initialized, but there is absolutely no point in
acquiring this lock because the timer is guaranteed not to run it's
callback for which the caller waits to finish on that base. So it would
just do the inc/lock/dec/unlock dance for nothing.

As the base switch is short and non-preemptible, there is no issue when the
wait function returns immediately.

The timer base and base->cpu_base cannot be NULL in the code path which is
invoking that, so just replace those checks with a check whether base is
migration base.

[ tglx: Updated from RT patch. Massaged changelog. Added comment. ]

Signed-off-by: Julien Grall <julien.grall@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190821092409.13225-4-julien.grall@arm.com
5 months agohrtimer: Protect lockless access to timer->base
Julien Grall [Wed, 21 Aug 2019 09:24:07 +0000 (10:24 +0100)]
hrtimer: Protect lockless access to timer->base

The update to timer->base is protected by the base->cpu_base->lock().
However, hrtimer_cancel_wait_running() does access it lockless.  So the
compiler is allowed to refetch timer->base which can cause havoc when the
timer base is changed concurrently.

Use READ_ONCE() to prevent this.

[ tglx: Adapted from a RT patch ]

Signed-off-by: Julien Grall <julien.grall@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190821092409.13225-2-julien.grall@arm.com
5 months agoposix-cpu-timers: Fixup stale comment
Thomas Gleixner [Mon, 19 Aug 2019 14:31:45 +0000 (16:31 +0200)]
posix-cpu-timers: Fixup stale comment

The comment above cleanup_timers() is outdated. The timers are only removed
from the task/process list heads but not modified in any other way.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190819143801.747233612@linutronix.de
5 months agoalarmtimers: Avoid rtc.h include
Thomas Gleixner [Mon, 19 Aug 2019 14:31:43 +0000 (16:31 +0200)]
alarmtimers: Avoid rtc.h include

rtc.h is not needed in alarmtimers when a forward declaration of struct
rtc_device is provided. That allows to include posix-timers.h without
adding more includes to alarmtimer.h or creating circular include
dependencies.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190819143801.565389536@linutronix.de
5 months agoposix-timers: Cleanup forward declarations and includes
Thomas Gleixner [Mon, 19 Aug 2019 14:31:42 +0000 (16:31 +0200)]
posix-timers: Cleanup forward declarations and includes

 - Rename struct siginfo to kernel_siginfo as that is used and required
 - Add a forward declaration for task_struct and remove sched.h include
 - Remove timex.h include as it is not needed

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190819143801.472005793@linutronix.de
5 months agohrtimer: Improve comments on handling priority inversion against softirq kthread
Frederic Weisbecker [Tue, 20 Aug 2019 13:12:23 +0000 (15:12 +0200)]
hrtimer: Improve comments on handling priority inversion against softirq kthread

The handling of a priority inversion between timer cancelling and a a not
well defined possible preemption of softirq kthread is not very clear.

Especially in the posix timers side it's unclear why there is a specific RT
wait callback.

All the nice explanations can be found in the initial changelog of
f61eff83cec9 (hrtimer: Prepare support for PREEMPT_RT").

Extract the detailed informations from there and put it into comments.

Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190820132656.GC2093@lenoir
5 months agoposix-timers: Use a callback for cancel synchronization on PREEMPT_RT
Thomas Gleixner [Fri, 2 Aug 2019 05:35:59 +0000 (07:35 +0200)]
posix-timers: Use a callback for cancel synchronization on PREEMPT_RT

Posix timer delete retry loops are affected by the same priority inversion
and live lock issues as the other timers.

Provide a RT specific synchronization function which keeps a reference to
the timer by holding rcu read lock to prevent the timer from being freed,
dropping the timer lock and invoking the timer specific wait function via a
new callback.

This does not yet cover posix CPU timers because they need more special
treatment on PREEMPT_RT.

[ This is folded into the original attempt which did not use a callback. ]

Originally-by: Anna-Maria Gleixenr <anna-maria@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190819143801.656864506@linutronix.de
5 months agoposix-timers: Move rcu_head out of it union
Sebastian Andrzej Siewior [Tue, 30 Jul 2019 22:33:54 +0000 (00:33 +0200)]
posix-timers: Move rcu_head out of it union

Timer deletion on PREEMPT_RT is prone to priority inversion and live
locks. The hrtimer code has a synchronization mechanism for this. Posix CPU
timers will grow one.

But that mechanism cannot be invoked while holding the k_itimer lock
because that can deadlock against the running timer callback. So the lock
must be dropped which allows the timer to be freed.

The timer free can be prevented by taking RCU readlock before dropping the
lock, but because the rcu_head is part of the 'it' union a concurrent free
will overwrite the hrtimer on which the task is trying to synchronize.

Move the rcu_head out of the union to prevent this.

[ tglx: Fixed up kernel-doc. Rewrote changelog ]

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190730223828.965541887@linutronix.de
5 months agoposix-timers: Rework cancel retry loops
Thomas Gleixner [Tue, 30 Jul 2019 22:33:53 +0000 (00:33 +0200)]
posix-timers: Rework cancel retry loops

As a preparatory step for adding the PREEMPT RT specific synchronization
mechanism to wait for a running timer callback, rework the timer cancel
retry loops so they call a common function. This allows trivial
substitution in one place.

Originally-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190730223828.874901027@linutronix.de
5 months agoposix-timers: Cleanup the flag/flags confusion
Thomas Gleixner [Tue, 30 Jul 2019 22:33:52 +0000 (00:33 +0200)]
posix-timers: Cleanup the flag/flags confusion

do_timer_settime() has a 'flags' argument and uses 'flag' for the interrupt
flags, which is confusing at best.

Rename the argument so 'flags' can be used for interrupt flags as usual.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190730223828.782664411@linutronix.de
5 months agoitimers: Prepare for PREEMPT_RT
Anna-Maria Gleixner [Tue, 30 Jul 2019 22:33:51 +0000 (00:33 +0200)]
itimers: Prepare for PREEMPT_RT

Use the hrtimer_cancel_wait_running() synchronization mechanism to prevent
priority inversion and live locks on PREEMPT_RT.

As a benefit the retry loop gains the missing cpu_relax() on !RT.

[ tglx: Split out of combo patch ]

Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190730223828.690771827@linutronix.de
5 months agotimerfd: Prepare for PREEMPT_RT
Anna-Maria Gleixner [Tue, 30 Jul 2019 22:33:50 +0000 (00:33 +0200)]
timerfd: Prepare for PREEMPT_RT

Use the hrtimer_cancel_wait_running() synchronization mechanism to prevent
priority inversion and live locks on PREEMPT_RT.

[ tglx: Split out of combo patch ]

Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190730223828.600085866@linutronix.de
5 months agoalarmtimer: Prepare for PREEMPT_RT
Anna-Maria Gleixner [Tue, 30 Jul 2019 22:33:49 +0000 (00:33 +0200)]
alarmtimer: Prepare for PREEMPT_RT

Use the hrtimer_cancel_wait_running() synchronization mechanism to prevent
priority inversion and live locks on PREEMPT_RT.

[ tglx: Split out of combo patch ]

Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190730223828.508744705@linutronix.de
5 months agosched/deadline: Ensure inactive_timer runs in hardirq context
Juri Lelli [Wed, 31 Jul 2019 10:37:15 +0000 (12:37 +0200)]
sched/deadline: Ensure inactive_timer runs in hardirq context

SCHED_DEADLINE inactive timer needs to run in hardirq context (as
dl_task_timer already does) on PREEMPT_RT

Change the mode to HRTIMER_MODE_REL_HARD.

[ tglx: Fixed up the start site, so mode debugging works ]

Signed-off-by: Juri Lelli <juri.lelli@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190731103715.4047-1-juri.lelli@redhat.com
5 months agotimers: Prepare support for PREEMPT_RT
Anna-Maria Gleixner [Fri, 26 Jul 2019 18:31:00 +0000 (20:31 +0200)]
timers: Prepare support for PREEMPT_RT

When PREEMPT_RT is enabled, the soft interrupt thread can be preempted.  If
the soft interrupt thread is preempted in the middle of a timer callback,
then calling del_timer_sync() can lead to two issues:

  - If the caller is on a remote CPU then it has to spin wait for the timer
    handler to complete. This can result in unbound priority inversion.

  - If the caller originates from the task which preempted the timer
    handler on the same CPU, then spin waiting for the timer handler to
    complete is never going to end.

To avoid these issues, add a new lock to the timer base which is held
around the execution of the timer callbacks. If del_timer_sync() detects
that the timer callback is currently running, it blocks on the expiry
lock. When the callback is finished, the expiry lock is dropped by the
softirq thread which wakes up the waiter and the system makes progress.

This addresses both the priority inversion and the life lock issues.

This mechanism is not used for timers which are marked IRQSAFE as for those
preemption is disabled accross the callback and therefore this situation
cannot happen. The callbacks for such timers need to be individually
audited for RT compliance.

The same issue can happen in virtual machines when the vCPU which runs a
timer callback is scheduled out. If a second vCPU of the same guest calls
del_timer_sync() it will spin wait for the other vCPU to be scheduled back
in. The expiry lock mechanism would avoid that. It'd be trivial to enable
this when paravirt spinlocks are enabled in a guest, but it's not clear
whether this is an actual problem in the wild, so for now it's an RT only
mechanism.

As the softirq thread can be preempted with PREEMPT_RT=y, the SMP variant
of del_timer_sync() needs to be used on UP as well.

[ tglx: Refactored it for mainline ]

Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190726185753.832418500@linutronix.de
5 months agohrtimer: Prepare support for PREEMPT_RT
Anna-Maria Gleixner [Fri, 26 Jul 2019 18:30:59 +0000 (20:30 +0200)]
hrtimer: Prepare support for PREEMPT_RT

When PREEMPT_RT is enabled, the soft interrupt thread can be preempted.  If
the soft interrupt thread is preempted in the middle of a timer callback,
then calling hrtimer_cancel() can lead to two issues:

  - If the caller is on a remote CPU then it has to spin wait for the timer
    handler to complete. This can result in unbound priority inversion.

  - If the caller originates from the task which preempted the timer
    handler on the same CPU, then spin waiting for the timer handler to
    complete is never going to end.

To avoid these issues, add a new lock to the timer base which is held
around the execution of the timer callbacks. If hrtimer_cancel() detects
that the timer callback is currently running, it blocks on the expiry
lock. When the callback is finished, the expiry lock is dropped by the
softirq thread which wakes up the waiter and the system makes progress.

This addresses both the priority inversion and the life lock issues.

The same issue can happen in virtual machines when the vCPU which runs a
timer callback is scheduled out. If a second vCPU of the same guest calls
hrtimer_cancel() it will spin wait for the other vCPU to be scheduled back
in. The expiry lock mechanism would avoid that. It'd be trivial to enable
this when paravirt spinlocks are enabled in a guest, but it's not clear
whether this is an actual problem in the wild, so for now it's an RT only
mechanism.

[ tglx: Refactored it for mainline ]

Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190726185753.737767218@linutronix.de
5 months agohrtimer: Determine hard/soft expiry mode for hrtimer sleepers on RT
Sebastian Andrzej Siewior [Fri, 26 Jul 2019 18:30:58 +0000 (20:30 +0200)]
hrtimer: Determine hard/soft expiry mode for hrtimer sleepers on RT

On PREEMPT_RT enabled kernels hrtimers which are not explicitely marked for
hard interrupt expiry mode are moved into soft interrupt context either for
latency reasons or because the hrtimer callback takes regular spinlocks or
invokes other functions which are not suitable for hard interrupt context
on PREEMPT_RT.

The hrtimer_sleeper callback is RT compatible in hard interrupt context,
but there is a latency concern: Untrusted userspace can spawn many threads
which arm timers for the same expiry time on the same CPU. On expiry that
causes a latency spike due to the wakeup of a gazillion threads.

OTOH, priviledged real-time user space applications rely on the low latency
of hard interrupt wakeups. These syscall related wakeups are all based on
hrtimer sleepers.

If the current task is in a real-time scheduling class, mark the mode for
hard interrupt expiry.

[ tglx: Split out of a larger combo patch. Added changelog ]

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190726185753.645792403@linutronix.de
5 months agohrtimer: Move unmarked hrtimers to soft interrupt expiry on RT
Sebastian Andrzej Siewior [Fri, 26 Jul 2019 18:30:57 +0000 (20:30 +0200)]
hrtimer: Move unmarked hrtimers to soft interrupt expiry on RT

On PREEMPT_RT not all hrtimers can be expired in hard interrupt context
even if that is perfectly fine on a PREEMPT_RT=n kernel, e.g. because they
take regular spinlocks. Also for latency reasons PREEMPT_RT tries to defer
most hrtimers' expiry into softirq context.

hrtimers marked with HRTIMER_MODE_HARD must be kept in hard interrupt
context expiry mode. Add the required logic.

No functional change for PREEMPT_RT=n kernels.

[ tglx: Split out of a larger combo patch. Added changelog ]

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190726185753.551967692@linutronix.de
5 months agotick: Mark tick related hrtimers to expiry in hard interrupt context
Sebastian Andrzej Siewior [Fri, 26 Jul 2019 18:30:56 +0000 (20:30 +0200)]
tick: Mark tick related hrtimers to expiry in hard interrupt context

The tick related hrtimers, which drive the scheduler tick and hrtimer based
broadcasting are required to expire in hard interrupt context for obvious
reasons.

Mark them so PREEMPT_RT kernels wont move them to soft interrupt expiry.

Make the horribly formatted RCU_NONIDLE bracket maze readable while at it.

No functional change,

[ tglx: Split out from larger combo patch. Add changelog ]

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190726185753.459144407@linutronix.de
5 months agoKVM: LAPIC: Mark hrtimer to expire in hard interrupt context
Sebastian Andrzej Siewior [Fri, 26 Jul 2019 18:30:55 +0000 (20:30 +0200)]
KVM: LAPIC: Mark hrtimer to expire in hard interrupt context

On PREEMPT_RT enabled kernels unmarked hrtimers are moved into soft
interrupt expiry mode by default.

While that's not a functional requirement for the KVM local APIC timer
emulation, it's a latency issue which can be avoided by marking the timer
so hard interrupt context expiry is enforced.

No functional change.

[ tglx: Split out from larger combo patch. Add changelog. ]

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190726185753.363363474@linutronix.de
5 months agowatchdog: Mark watchdog_hrtimer to expire in hard interrupt context
Sebastian Andrzej Siewior [Fri, 26 Jul 2019 18:30:54 +0000 (20:30 +0200)]
watchdog: Mark watchdog_hrtimer to expire in hard interrupt context

The watchdog hrtimer must expire in hard interrupt context even on
PREEMPT_RT=y kernels as otherwise the hard/softlockup detection logic would
not work.

No functional change.

[ tglx: Split out from larger combo patch. Added changelog ]

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190726185753.262895510@linutronix.de
5 months agoperf/core: Mark hrtimers to expire in hard interrupt context
Sebastian Andrzej Siewior [Fri, 26 Jul 2019 18:30:53 +0000 (20:30 +0200)]
perf/core: Mark hrtimers to expire in hard interrupt context

To guarantee that the multiplexing mechanism and the hrtimer driven events
work on PREEMPT_RT enabled kernels it's required that the related hrtimers
expire in hard interrupt context. Mark them so PREEMPT_RT kernels wont
defer them to soft interrupt context.

No functional change.

[ tglx: Split out of larger combo patch. Added changelog ]

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190726185753.169509224@linutronix.de
5 months agosched: Mark hrtimers to expire in hard interrupt context
Sebastian Andrzej Siewior [Fri, 26 Jul 2019 18:30:52 +0000 (20:30 +0200)]
sched: Mark hrtimers to expire in hard interrupt context

The scheduler related hrtimers need to expire in hard interrupt context
even on PREEMPT_RT enabled kernels. Mark then as such.

No functional change.

[ tglx: Split out from larger combo patch. Add changelog. ]

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190726185753.077004842@linutronix.de
5 months agohrtimer: Make enqueue mode check work on RT
Thomas Gleixner [Tue, 30 Jul 2019 18:15:25 +0000 (20:15 +0200)]
hrtimer: Make enqueue mode check work on RT

hrtimer_start_range_ns() has a WARN_ONCE() which verifies that a timer
which is marker for softirq expiry is not queued in the hard interrupt base
and vice versa.

When PREEMPT_RT is enabled, timers which are not explicitely marked to
expire in hard interrupt context are deferrred to the soft interrupt. So
the regular check would trigger.

Change the check, so when PREEMPT_RT is enabled, it is verified that the
timers marked for hard interrupt expiry are not tried to be queued for soft
interrupt expiry or any of the unmarked and softirq marked is tried to be
expired in hard interrupt context.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
5 months agohrtimer: Introduce HARD expiry mode
Sebastian Andrzej Siewior [Fri, 26 Jul 2019 18:30:51 +0000 (20:30 +0200)]
hrtimer: Introduce HARD expiry mode

On PREEMPT_RT not all hrtimers can be expired in hard interrupt context
even if that is perfectly fine on a PREEMPT_RT=n kernel, e.g. because they
take regular spinlocks. Also for latency reasons PREEMPT_RT tries to defer
most hrtimers' expiry into soft interrupt context.

But there are hrtimers which must be expired in hard interrupt context even
when PREEMPT_RT is enabled:

  - hrtimers which must expiry in hard interrupt context, e.g. scheduler,
    perf, watchdog related hrtimers

  - latency critical hrtimers, e.g. nanosleep, ..., kvm lapic timer

Add a new mode flag HRTIMER_MODE_HARD which allows to mark these timers so
PREEMPT_RT will not move them into softirq expiry mode.

[ tglx: Split out of a larger combo patch. Added changelog ]

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190726185752.981398465@linutronix.de
5 months agohrtimer/treewide: Use hrtimer_sleeper_start_expires()
Thomas Gleixner [Tue, 30 Jul 2019 19:16:55 +0000 (21:16 +0200)]
hrtimer/treewide: Use hrtimer_sleeper_start_expires()

hrtimer_sleepers will gain a scheduling class dependent treatment on
PREEMPT_RT. Use the new hrtimer_sleeper_start_expires() function to make
that possible.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
5 months agohrtimer: Provide hrtimer_sleeper_start_expires()
Thomas Gleixner [Tue, 30 Jul 2019 19:03:53 +0000 (21:03 +0200)]
hrtimer: Provide hrtimer_sleeper_start_expires()

hrtimer_sleepers will gain a scheduling class dependent treatment on
PREEMPT_RT. Create a wrapper around hrtimer_start_expires() to make that
possible.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
5 months agohrtimer: Consolidate hrtimer_init() + hrtimer_init_sleeper() calls
Sebastian Andrzej Siewior [Fri, 26 Jul 2019 18:30:50 +0000 (20:30 +0200)]
hrtimer: Consolidate hrtimer_init() + hrtimer_init_sleeper() calls

hrtimer_init_sleeper() calls require prior initialisation of the hrtimer
object which is embedded into the hrtimer_sleeper.

Combine the initialization and spare a function call. Fixup all call sites.

This is also a preparatory change for PREEMPT_RT to do hrtimer sleeper
specific initializations of the embedded hrtimer without modifying any of
the call sites.

No functional change.

[ anna-maria: Minor cleanups ]
[ tglx: Adopted to the removal of the task argument of
   hrtimer_init_sleeper() and trivial polishing.
Folded a fix from Stephen Rothwell for the vsoc code ]

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190726185752.887468908@linutronix.de
5 months agohrtimer: Remove task argument from hrtimer_init_sleeper()
Thomas Gleixner [Fri, 26 Jul 2019 18:30:49 +0000 (20:30 +0200)]
hrtimer: Remove task argument from hrtimer_init_sleeper()

All callers hand in 'current' and that's the only task pointer which
actually makes sense. Remove the task argument and set current in the
function.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190726185752.791885290@linutronix.de
5 months agolib/timerqueue: Rely on rbtree semantics for next timer
Davidlohr Bueso [Wed, 24 Jul 2019 15:23:23 +0000 (08:23 -0700)]
lib/timerqueue: Rely on rbtree semantics for next timer

Simplify the timerqueue code by using cached rbtrees and rely on the tree
leftmost node semantics to get the timer with earliest expiration time.
This is a drop in conversion, and therefore semantics remain untouched.

The runtime overhead of cached rbtrees is be pretty much the same as the
current head->next method, noting that when removing the leftmost node,
a common operation for the timerqueue, the rb_next(leftmost) is O(1) as
well, so the next timer will either be the right node or its parent.
Therefore no extra pointer chasing. Finally, the size of the struct
timerqueue_head remains the same.

Passes several hours of rcutorture.

Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190724152323.bojciei3muvfxalm@linux-r8p5
6 months agoMerge branch 'parisc-5.3-3' of git://git.kernel.org/pub/scm/linux/kernel/git/deller...
Linus Torvalds [Tue, 23 Jul 2019 22:34:59 +0000 (15:34 -0700)]
Merge branch 'parisc-5.3-3' of git://git./linux/kernel/git/deller/parisc-linux

Pull parisc fixes from Helge Deller:

 - Fix build issues when kprobes are enabled

 - Speed up ITLB/DTLB cache flushes when running on machines with
   combined TLBs

* 'parisc-5.3-3' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
  parisc: Flush ITLB in flush_tlb_all_local() only on split TLB machines
  parisc: add kprobe_fault_handler()

6 months agoMerge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...
Linus Torvalds [Mon, 22 Jul 2019 16:30:34 +0000 (09:30 -0700)]
Merge branch 'sched-urgent-for-linus' of git://git./linux/kernel/git/tip/tip

Pull preemption Kconfig fix from Thomas Gleixner:
 "The PREEMPT_RT stub config renamed PREEMPT to PREEMPT_LL and defined
  PREEMPT outside of the menu and made it selectable by both PREEMPT_LL
  and PREEMPT_RT.

  Stupid me missed that 114 defconfigs select CONFIG_PREEMPT which
  obviously can't work anymore. oldconfig builds are affected as well,
  but it's more obvious as the user gets asked. [old]defconfig silently
  fixes it up and selects PREEMPT_NONE.

  Unbreak it by undoing the rename and adding a intermediate config
  symbol which is selected by both PREEMPT and PREEMPT_RT. That requires
  to chase down a few #ifdefs, but it's better than tweaking 114
  defconfigs and annoying users"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/rt, Kconfig: Unbreak def/oldconfig with CONFIG_PREEMPT=y

6 months agoMerge tag 'for-linus-20190722' of git://git.kernel.org/pub/scm/linux/kernel/git/braun...
Linus Torvalds [Mon, 22 Jul 2019 16:14:19 +0000 (09:14 -0700)]
Merge tag 'for-linus-20190722' of git://git./linux/kernel/git/brauner/linux

Pull pidfd polling fix from Christian Brauner:
 "A fix for pidfd polling. It ensures that the task's exit state is
  visible to all waiters"

* tag 'for-linus-20190722' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
  pidfd: fix a poll race when setting exit_state

6 months agoMerge tag 'for-5.3-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave...
Linus Torvalds [Mon, 22 Jul 2019 16:08:38 +0000 (09:08 -0700)]
Merge tag 'for-5.3-rc1-tag' of git://git./linux/kernel/git/kdave/linux

Pull btrfs fixes from David Sterba:

 - fixes for leaks caused by recently merged patches

 - one build fix

 - a fix to prevent mixing of incompatible features

* tag 'for-5.3-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: don't leak extent_map in btrfs_get_io_geometry()
  btrfs: free checksum hash on in close_ctree
  btrfs: Fix build error while LIBCRC32C is module
  btrfs: inode: Don't compress if NODATASUM or NODATACOW set

6 months agosched/rt, Kconfig: Unbreak def/oldconfig with CONFIG_PREEMPT=y
Thomas Gleixner [Mon, 22 Jul 2019 15:59:19 +0000 (17:59 +0200)]
sched/rt, Kconfig: Unbreak def/oldconfig with CONFIG_PREEMPT=y

The merge of the CONFIG_PREEMPT_RT stub renamed CONFIG_PREEMPT to
CONFIG_PREEMPT_LL which causes all defconfigs which have CONFIG_PREEMPT=y
set to fall back to CONFIG_PREEMPT_NONE because CONFIG_PREEMPT depends on
the preemption mode choice wich defaults to NONE. This also affects
oldconfig builds.

So rather than changing 114 defconfig files and being an annoyance to
users, revert the rename and select a new config symbol PREEMPTION. That
keeps everything working smoothly and the revelant ifdef's are going to be
fixed up step by step.

Reported-by: Mark Rutland <mark.rutland@arm.com>
Fixes: a50a3f4b6a31 ("sched/rt, Kconfig: Introduce CONFIG_PREEMPT_RT")
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
6 months agoMerge tag 'media/v5.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab...
Linus Torvalds [Mon, 22 Jul 2019 16:01:47 +0000 (09:01 -0700)]
Merge tag 'media/v5.3-2' of git://git./linux/kernel/git/mchehab/linux-media

Pull media fixes from Mauro Carvalho Chehab:
 "For two regressions in media core:

   - v4l2-subdev: fix regression in check_pad()

   - videodev2.h: change V4L2_PIX_FMT_BGRA444 define: fourcc was already
     in use"

* tag 'media/v5.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media:
  media: videodev2.h: change V4L2_PIX_FMT_BGRA444 define: fourcc was already in use
  media: v4l2-subdev: fix regression in check_pad()

6 months agoMerge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Linus Torvalds [Mon, 22 Jul 2019 15:49:22 +0000 (08:49 -0700)]
Merge git://git./linux/kernel/git/davem/net

Pull networking fixes from David Miller:

 1) Several netfilter fixes including a nfnetlink deadlock fix from
    Florian Westphal and fix for dropping VRF packets from Miaohe Lin.

 2) Flow offload fixes from Pablo Neira Ayuso including a fix to restore
    proper block sharing.

 3) Fix r8169 PHY init from Thomas Voegtle.

 4) Fix memory leak in mac80211, from Lorenzo Bianconi.

 5) Missing NULL check on object allocation in cxgb4, from Navid
    Emamdoost.

 6) Fix scaling of RX power in sfp phy driver, from Andrew Lunn.

 7) Check that there is actually an ip header to access in skb->data in
    VRF, from Peter Kosyh.

 8) Remove spurious rcu unlock in hv_netvsc, from Haiyang Zhang.

 9) One more tweak the the TCP fragmentation memory limit changes, to be
    less harmful to applications setting small SO_SNDBUF values. From
    Eric Dumazet.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (40 commits)
  tcp: be more careful in tcp_fragment()
  hv_netvsc: Fix extra rcu_read_unlock in netvsc_recv_callback()
  vrf: make sure skb->data contains ip header to make routing
  connector: remove redundant input callback from cn_dev
  qed: Prefer pcie_capability_read_word()
  igc: Prefer pcie_capability_read_word()
  cxgb4: Prefer pcie_capability_read_word()
  be2net: Synchronize be_update_queues with dev_watchdog
  bnx2x: Prevent load reordering in tx completion processing
  net: phy: sfp: hwmon: Fix scaling of RX power
  net: sched: verify that q!=NULL before setting q->flags
  chelsio: Fix a typo in a function name
  allocate_flower_entry: should check for null deref
  net: hns3: typo in the name of a constant
  kbuild: add net/netfilter/nf_tables_offload.h to header-test blacklist.
  tipc: Fix a typo
  mac80211: don't warn about CW params when not using them
  mac80211: fix possible memory leak in ieee80211_assign_beacon
  nl80211: fix NL80211_HE_MAX_CAPABILITY_LEN
  nl80211: fix VENDOR_CMD_RAW_DATA
  ...