linux.git/kernel/time, branch v4.13 Linux kernel source tree time: Fix ktime_get_raw() incorrect base accumulation 2017-08-26T14:06:12+00:00 John Stultz john.stultz@linaro.org 2017-08-25T22:57:04+00:00 0bcdc0987cce9880436b70836c6a92bb8e744fd1 In comqit fc6eead7c1e2 ("time: Clean up CLOCK_MONOTONIC_RAW time handling"), the following code got mistakenly added to the update of the raw timekeeper: /* Update the monotonic raw base */ seconds = tk->raw_sec; nsec = (u32)(tk->tkr_raw.xtime_nsec >> tk->tkr_raw.shift); tk->tkr_raw.base = ns_to_ktime(seconds * NSEC_PER_SEC + nsec); Which adds the raw_sec value and the shifted down raw xtime_nsec to the base value. But the read function adds the shifted down tk->tkr_raw.xtime_nsec value another time, The result of this is that ktime_get_raw() users (which are all internal users) see the raw time move faster then it should (the rate at which can vary with the current size of tkr_raw.xtime_nsec), which has resulted in at least problems with graphics rendering performance. The change tried to match the monotonic base update logic: seconds = (u64)(tk->xtime_sec + tk->wall_to_monotonic.tv_sec); nsec = (u32) tk->wall_to_monotonic.tv_nsec; tk->tkr_mono.base = ns_to_ktime(seconds * NSEC_PER_SEC + nsec); Which adds the wall_to_monotonic.tv_nsec value, but not the tk->tkr_mono.xtime_nsec value to the base. To fix this, simplify the tkr_raw.base accumulation to only accumulate the raw_sec portion, and do not include the tkr_raw.xtime_nsec portion, which will be added at read time. Fixes: fc6eead7c1e2 ("time: Clean up CLOCK_MONOTONIC_RAW time handling") Reported-and-tested-by: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: John Stultz <john.stultz@linaro.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Kevin Brodsky <kevin.brodsky@arm.com> Cc: Richard Cochran <richardcochran@gmail.com> Cc: Stephen Boyd <stephen.boyd@linaro.org> Cc: Will Deacon <will.deacon@arm.com> Cc: Miroslav Lichvar <mlichvar@redhat.com> Cc: Daniel Mentz <danielmentz@google.com> Link: http://lkml.kernel.org/r/1503701824-1645-1-git-send-email-john.stultz@linaro.org 
In comqit fc6eead7c1e2 ("time: Clean up CLOCK_MONOTONIC_RAW time
handling"), the following code got mistakenly added to the update of the
raw timekeeper:

 /* Update the monotonic raw base */
 seconds = tk->raw_sec;
 nsec = (u32)(tk->tkr_raw.xtime_nsec >> tk->tkr_raw.shift);
 tk->tkr_raw.base = ns_to_ktime(seconds * NSEC_PER_SEC + nsec);

Which adds the raw_sec value and the shifted down raw xtime_nsec to the
base value.

But the read function adds the shifted down tk->tkr_raw.xtime_nsec value
another time, The result of this is that ktime_get_raw() users (which are
all internal users) see the raw time move faster then it should (the rate
at which can vary with the current size of tkr_raw.xtime_nsec), which has
resulted in at least problems with graphics rendering performance.

The change tried to match the monotonic base update logic:

 seconds = (u64)(tk->xtime_sec + tk->wall_to_monotonic.tv_sec);
 nsec = (u32) tk->wall_to_monotonic.tv_nsec;
 tk->tkr_mono.base = ns_to_ktime(seconds * NSEC_PER_SEC + nsec);

Which adds the wall_to_monotonic.tv_nsec value, but not the
tk->tkr_mono.xtime_nsec value to the base.

To fix this, simplify the tkr_raw.base accumulation to only accumulate the
raw_sec portion, and do not include the tkr_raw.xtime_nsec portion, which
will be added at read time.

Fixes: fc6eead7c1e2 ("time: Clean up CLOCK_MONOTONIC_RAW time handling")
Reported-and-tested-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Stephen Boyd <stephen.boyd@linaro.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Miroslav Lichvar <mlichvar@redhat.com>
Cc: Daniel Mentz <danielmentz@google.com>
Link: http://lkml.kernel.org/r/1503701824-1645-1-git-send-email-john.stultz@linaro.org
timers: Fix excessive granularity of new timers after a nohz idle 2017-08-24T09:40:18+00:00 Nicholas Piggin npiggin@gmail.com 2017-08-22T08:43:48+00:00 2fe59f507a65dbd734b990a11ebc7488f6f87a24 When a timer base is idle, it is forwarded when a new timer is added to ensure that granularity does not become excessive. When not idle, the timer tick is expected to increment the base. However there are several problems: - If an existing timer is modified, the base is forwarded only after the index is calculated. - The base is not forwarded by add_timer_on. - There is a window after a timer is restarted from a nohz idle, after it is marked not-idle and before the timer tick on this CPU, where a timer may be added but the ancient base does not get forwarded. These result in excessive granularity (a 1 jiffy timeout can blow out to 100s of jiffies), which cause the rcu lockup detector to trigger, among other things. Fix this by keeping track of whether the timer base has been idle since it was last run or forwarded, and if so then forward it before adding a new timer. There is still a case where mod_timer optimises the case of a pending timer mod with the same expiry time, where the timer can see excessive granularity relative to the new, shorter interval. A comment is added, but it's not changed because it is an important fastpath for networking. This has been tested and found to fix the RCU softlockup messages. Testing was also done with tracing to measure requested versus achieved wakeup latencies for all non-deferrable timers in an idle system (with no lockup watchdogs running). Wakeup latency relative to absolute latency is calculated (note this suffers from round-up skew at low absolute times) and analysed: max avg std upstream 506.0 1.20 4.68 patched 2.0 1.08 0.15 The bug was noticed due to the lockup detector Kconfig changes dropping it out of people's .configs and resulting in larger base clk skew When the lockup detectors are enabled, no CPU can go idle for longer than 4 seconds, which limits the granularity errors. Sub-optimal timer behaviour is observable on a smaller scale in that case: max avg std upstream 9.0 1.05 0.19 patched 2.0 1.04 0.11 Fixes: Fixes: a683f390b93f ("timers: Forward the wheel clock whenever possible") Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Tested-by: David Miller <davem@davemloft.net> Cc: dzickus@redhat.com Cc: sfr@canb.auug.org.au Cc: mpe@ellerman.id.au Cc: Stephen Boyd <sboyd@codeaurora.org> Cc: linuxarm@huawei.com Cc: abdhalee@linux.vnet.ibm.com Cc: John Stultz <john.stultz@linaro.org> Cc: akpm@linux-foundation.org Cc: paulmck@linux.vnet.ibm.com Cc: torvalds@linux-foundation.org Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/20170822084348.21436-1-npiggin@gmail.com 
When a timer base is idle, it is forwarded when a new timer is added
to ensure that granularity does not become excessive. When not idle,
the timer tick is expected to increment the base.

However there are several problems:

- If an existing timer is modified, the base is forwarded only after
  the index is calculated.

- The base is not forwarded by add_timer_on.

- There is a window after a timer is restarted from a nohz idle, after
  it is marked not-idle and before the timer tick on this CPU, where a
  timer may be added but the ancient base does not get forwarded.

These result in excessive granularity (a 1 jiffy timeout can blow out
to 100s of jiffies), which cause the rcu lockup detector to trigger,
among other things.

Fix this by keeping track of whether the timer base has been idle
since it was last run or forwarded, and if so then forward it before
adding a new timer.

There is still a case where mod_timer optimises the case of a pending
timer mod with the same expiry time, where the timer can see excessive
granularity relative to the new, shorter interval. A comment is added,
but it's not changed because it is an important fastpath for
networking.

This has been tested and found to fix the RCU softlockup messages.

Testing was also done with tracing to measure requested versus
achieved wakeup latencies for all non-deferrable timers in an idle
system (with no lockup watchdogs running). Wakeup latency relative to
absolute latency is calculated (note this suffers from round-up skew
at low absolute times) and analysed:

             max     avg      std
upstream   506.0    1.20     4.68
patched      2.0    1.08     0.15

The bug was noticed due to the lockup detector Kconfig changes
dropping it out of people's .configs and resulting in larger base
clk skew When the lockup detectors are enabled, no CPU can go idle for
longer than 4 seconds, which limits the granularity errors.
Sub-optimal timer behaviour is observable on a smaller scale in that
case:

	     max     avg      std
upstream     9.0    1.05     0.19
patched      2.0    1.04     0.11

Fixes: Fixes: a683f390b93f ("timers: Forward the wheel clock whenever possible")
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Tested-by: David Miller <davem@davemloft.net>
Cc: dzickus@redhat.com
Cc: sfr@canb.auug.org.au
Cc: mpe@ellerman.id.au
Cc: Stephen Boyd <sboyd@codeaurora.org>
Cc: linuxarm@huawei.com
Cc: abdhalee@linux.vnet.ibm.com
Cc: John Stultz <john.stultz@linaro.org>
Cc: akpm@linux-foundation.org
Cc: paulmck@linux.vnet.ibm.com
Cc: torvalds@linux-foundation.org
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/20170822084348.21436-1-npiggin@gmail.com
timers: Fix overflow in get_next_timer_interrupt 2017-08-01T12:20:53+00:00 Matija Glavinic Pecotic matija.glavinic-pecotic.ext@nokia.com 2017-08-01T07:11:52+00:00 34f41c0316ed52b0b44542491d89278efdaa70e4 For e.g. HZ=100, timer being 430 jiffies in the future, and 32 bit unsigned int, there is an overflow on unsigned int right-hand side of the expression which results with wrong values being returned. Type cast the multiplier to 64bit to avoid that issue. Fixes: 46c8f0b077a8 ("timers: Fix get_next_timer_interrupt() computation") Signed-off-by: Matija Glavinic Pecotic <matija.glavinic-pecotic.ext@nokia.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexander Sverdlin <alexander.sverdlin@nokia.com> Cc: khilman@baylibre.com Cc: akpm@linux-foundation.org Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/a7900f04-2a21-c9fd-67be-ab334d459ee5@nokia.com 
For e.g. HZ=100, timer being 430 jiffies in the future, and 32 bit
unsigned int, there is an overflow on unsigned int right-hand side
of the expression which results with wrong values being returned.

Type cast the multiplier to 64bit to avoid that issue.

Fixes: 46c8f0b077a8 ("timers: Fix get_next_timer_interrupt() computation")
Signed-off-by: Matija Glavinic Pecotic <matija.glavinic-pecotic.ext@nokia.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Cc: khilman@baylibre.com
Cc: akpm@linux-foundation.org
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/a7900f04-2a21-c9fd-67be-ab334d459ee5@nokia.com
Merge branch 'timers-compat' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2017-07-05T22:34:35+00:00 Linus Torvalds torvalds@linux-foundation.org 2017-07-05T22:34:35+00:00 ea3b25e1320df4e575c323b6ab22a5fc79976fbe Pull timer-related user access updates from Al Viro: "Continuation of timers-related stuff (there had been more, but my parts of that series are already merged via timers/core). This is more of y2038 work by Deepa Dinamani, partially disrupted by the unification of native and compat timers-related syscalls" * 'timers-compat' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: posix_clocks: Use get_itimerspec64() and put_itimerspec64() timerfd: Use get_itimerspec64() and put_itimerspec64() nanosleep: Use get_timespec64() and put_timespec64() posix-timers: Use get_timespec64() and put_timespec64() posix-stubs: Conditionally include COMPAT_SYS_NI defines time: introduce {get,put}_itimerspec64 time: add get_timespec64 and put_timespec64 
Pull timer-related user access updates from Al Viro:
 "Continuation of timers-related stuff (there had been more, but my
  parts of that series are already merged via timers/core). This is more
  of y2038 work by Deepa Dinamani, partially disrupted by the
  unification of native and compat timers-related syscalls"

* 'timers-compat' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  posix_clocks: Use get_itimerspec64() and put_itimerspec64()
  timerfd: Use get_itimerspec64() and put_itimerspec64()
  nanosleep: Use get_timespec64() and put_timespec64()
  posix-timers: Use get_timespec64() and put_timespec64()
  posix-stubs: Conditionally include COMPAT_SYS_NI defines
  time: introduce {get,put}_itimerspec64
  time: add get_timespec64 and put_timespec64
Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-07-03T23:14:51+00:00 Linus Torvalds torvalds@linux-foundation.org 2017-07-03T23:14:51+00:00 1b044f1cfc65a7d90b209dfabd57e16d98b58c5b Pull timer updates from Thomas Gleixner: "A rather large update for timers/timekeeping: - compat syscall consolidation (Al Viro) - Posix timer consolidation (Christoph Helwig / Thomas Gleixner) - Cleanup of the device tree based initialization for clockevents and clocksources (Daniel Lezcano) - Consolidation of the FTTMR010 clocksource/event driver (Linus Walleij) - The usual set of small fixes and updates all over the place" * 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (93 commits) timers: Make the cpu base lock raw clocksource/drivers/mips-gic-timer: Fix an error code in 'gic_clocksource_of_init()' clocksource/drivers/fsl_ftm_timer: Unmap region obtained by of_iomap clocksource/drivers/tcb_clksrc: Make IO endian agnostic clocksource/drivers/sun4i: Switch to the timer-of common init clocksource/drivers/timer-of: Fix invalid iomap check Revert "ktime: Simplify ktime_compare implementation" clocksource/drivers: Fix uninitialized variable use in timer_of_init kselftests: timers: Add test for frequency step kselftests: timers: Fix inconsistency-check to not ignore first timestamp time: Add warning about imminent deprecation of CONFIG_GENERIC_TIME_VSYSCALL_OLD time: Clean up CLOCK_MONOTONIC_RAW time handling posix-cpu-timers: Make timespec to nsec conversion safe itimer: Make timeval to nsec conversion range limited timers: Fix parameter description of try_to_del_timer_sync() ktime: Simplify ktime_compare implementation clocksource/drivers/fttmr010: Factor out clock read code clocksource/drivers/fttmr010: Implement delay timer clocksource/drivers: Add timer-of common init routine clocksource/drivers/tcb_clksrc: Save timer context on suspend/resume ... 
Pull timer updates from Thomas Gleixner:
 "A rather large update for timers/timekeeping:

   - compat syscall consolidation (Al Viro)

   - Posix timer consolidation (Christoph Helwig / Thomas Gleixner)

   - Cleanup of the device tree based initialization for clockevents and
     clocksources (Daniel Lezcano)

   - Consolidation of the FTTMR010 clocksource/event driver (Linus
     Walleij)

   - The usual set of small fixes and updates all over the place"

* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (93 commits)
  timers: Make the cpu base lock raw
  clocksource/drivers/mips-gic-timer: Fix an error code in 'gic_clocksource_of_init()'
  clocksource/drivers/fsl_ftm_timer: Unmap region obtained by of_iomap
  clocksource/drivers/tcb_clksrc: Make IO endian agnostic
  clocksource/drivers/sun4i: Switch to the timer-of common init
  clocksource/drivers/timer-of: Fix invalid iomap check
  Revert "ktime: Simplify ktime_compare implementation"
  clocksource/drivers: Fix uninitialized variable use in timer_of_init
  kselftests: timers: Add test for frequency step
  kselftests: timers: Fix inconsistency-check to not ignore first timestamp
  time: Add warning about imminent deprecation of CONFIG_GENERIC_TIME_VSYSCALL_OLD
  time: Clean up CLOCK_MONOTONIC_RAW time handling
  posix-cpu-timers: Make timespec to nsec conversion safe
  itimer: Make timeval to nsec conversion range limited
  timers: Fix parameter description of try_to_del_timer_sync()
  ktime: Simplify ktime_compare implementation
  clocksource/drivers/fttmr010: Factor out clock read code
  clocksource/drivers/fttmr010: Implement delay timer
  clocksource/drivers: Add timer-of common init routine
  clocksource/drivers/tcb_clksrc: Save timer context on suspend/resume
  ...
Merge branch 'timers-nohz-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-07-03T20:33:57+00:00 Linus Torvalds torvalds@linux-foundation.org 2017-07-03T20:33:57+00:00 59b60185b4a1adc46b115291dc34af2186cc9678 Pull nohz updates from Ingo Molnar: "The main changes in this cycle relate to fixing another bad (but sporadic and hard to detect) interaction between the dynticks scheduler tick and hrtimers, plus related improvements to better detection and handling of similar problems - by Frédéric Weisbecker" * 'timers-nohz-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: nohz: Fix spurious warning when hrtimer and clockevent get out of sync nohz: Fix buggy tick delay on IRQ storms nohz: Reset next_tick cache even when the timer has no regs nohz: Fix collision between tick and other hrtimers, again nohz: Add hrtimer sanity check 
Pull nohz updates from Ingo Molnar:
 "The main changes in this cycle relate to fixing another bad (but
  sporadic and hard to detect) interaction between the dynticks
  scheduler tick and hrtimers, plus related improvements to better
  detection and handling of similar problems - by Frédéric Weisbecker"

* 'timers-nohz-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  nohz: Fix spurious warning when hrtimer and clockevent get out of sync
  nohz: Fix buggy tick delay on IRQ storms
  nohz: Reset next_tick cache even when the timer has no regs
  nohz: Fix collision between tick and other hrtimers, again
  nohz: Add hrtimer sanity check
Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-07-03T20:08:04+00:00 Linus Torvalds torvalds@linux-foundation.org 2017-07-03T20:08:04+00:00 9bd42183b951051f73de121f7ee17091e7d26fbb Pull scheduler updates from Ingo Molnar: "The main changes in this cycle were: - Add the SYSTEM_SCHEDULING bootup state to move various scheduler debug checks earlier into the bootup. This turns silent and sporadically deadly bugs into nice, deterministic splats. Fix some of the splats that triggered. (Thomas Gleixner) - A round of restructuring and refactoring of the load-balancing and topology code (Peter Zijlstra) - Another round of consolidating ~20 of incremental scheduler code history: this time in terms of wait-queue nomenclature. (I didn't get much feedback on these renaming patches, and we can still easily change any names I might have misplaced, so if anyone hates a new name, please holler and I'll fix it.) (Ingo Molnar) - sched/numa improvements, fixes and updates (Rik van Riel) - Another round of x86/tsc scheduler clock code improvements, in hope of making it more robust (Peter Zijlstra) - Improve NOHZ behavior (Frederic Weisbecker) - Deadline scheduler improvements and fixes (Luca Abeni, Daniel Bristot de Oliveira) - Simplify and optimize the topology setup code (Lauro Ramos Venancio) - Debloat and decouple scheduler code some more (Nicolas Pitre) - Simplify code by making better use of llist primitives (Byungchul Park) - ... plus other fixes and improvements" * 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (103 commits) sched/cputime: Refactor the cputime_adjust() code sched/debug: Expose the number of RT/DL tasks that can migrate sched/numa: Hide numa_wake_affine() from UP build sched/fair: Remove effective_load() sched/numa: Implement NUMA node level wake_affine() sched/fair: Simplify wake_affine() for the single socket case sched/numa: Override part of migrate_degrades_locality() when idle balancing sched/rt: Move RT related code from sched/core.c to sched/rt.c sched/deadline: Move DL related code from sched/core.c to sched/deadline.c sched/cpuset: Only offer CONFIG_CPUSETS if SMP is enabled sched/fair: Spare idle load balancing on nohz_full CPUs nohz: Move idle balancer registration to the idle path sched/loadavg: Generalize "_idle" naming to "_nohz" sched/core: Drop the unused try_get_task_struct() helper function sched/fair: WARN() and refuse to set buddy when !se->on_rq sched/debug: Fix SCHED_WARN_ON() to return a value on !CONFIG_SCHED_DEBUG as well sched/wait: Disambiguate wq_entry->task_list and wq_head->task_list naming sched/wait: Move bit_wait_table[] and related functionality from sched/core.c to sched/wait_bit.c sched/wait: Split out the wait_bit*() APIs from <linux/wait.h> into <linux/wait_bit.h> sched/wait: Re-adjust macro line continuation backslashes in <linux/wait.h> ... 
Pull scheduler updates from Ingo Molnar:
 "The main changes in this cycle were:

   - Add the SYSTEM_SCHEDULING bootup state to move various scheduler
     debug checks earlier into the bootup. This turns silent and
     sporadically deadly bugs into nice, deterministic splats. Fix some
     of the splats that triggered. (Thomas Gleixner)

   - A round of restructuring and refactoring of the load-balancing and
     topology code (Peter Zijlstra)

   - Another round of consolidating ~20 of incremental scheduler code
     history: this time in terms of wait-queue nomenclature. (I didn't
     get much feedback on these renaming patches, and we can still
     easily change any names I might have misplaced, so if anyone hates
     a new name, please holler and I'll fix it.) (Ingo Molnar)

   - sched/numa improvements, fixes and updates (Rik van Riel)

   - Another round of x86/tsc scheduler clock code improvements, in hope
     of making it more robust (Peter Zijlstra)

   - Improve NOHZ behavior (Frederic Weisbecker)

   - Deadline scheduler improvements and fixes (Luca Abeni, Daniel
     Bristot de Oliveira)

   - Simplify and optimize the topology setup code (Lauro Ramos
     Venancio)

   - Debloat and decouple scheduler code some more (Nicolas Pitre)

   - Simplify code by making better use of llist primitives (Byungchul
     Park)

   - ... plus other fixes and improvements"

* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (103 commits)
  sched/cputime: Refactor the cputime_adjust() code
  sched/debug: Expose the number of RT/DL tasks that can migrate
  sched/numa: Hide numa_wake_affine() from UP build
  sched/fair: Remove effective_load()
  sched/numa: Implement NUMA node level wake_affine()
  sched/fair: Simplify wake_affine() for the single socket case
  sched/numa: Override part of migrate_degrades_locality() when idle balancing
  sched/rt: Move RT related code from sched/core.c to sched/rt.c
  sched/deadline: Move DL related code from sched/core.c to sched/deadline.c
  sched/cpuset: Only offer CONFIG_CPUSETS if SMP is enabled
  sched/fair: Spare idle load balancing on nohz_full CPUs
  nohz: Move idle balancer registration to the idle path
  sched/loadavg: Generalize "_idle" naming to "_nohz"
  sched/core: Drop the unused try_get_task_struct() helper function
  sched/fair: WARN() and refuse to set buddy when !se->on_rq
  sched/debug: Fix SCHED_WARN_ON() to return a value on !CONFIG_SCHED_DEBUG as well
  sched/wait: Disambiguate wq_entry->task_list and wq_head->task_list naming
  sched/wait: Move bit_wait_table[] and related functionality from sched/core.c to sched/wait_bit.c
  sched/wait: Split out the wait_bit*() APIs from <linux/wait.h> into <linux/wait_bit.h>
  sched/wait: Re-adjust macro line continuation backslashes in <linux/wait.h>
  ...
Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-07-03T18:34:53+00:00 Linus Torvalds torvalds@linux-foundation.org 2017-07-03T18:34:53+00:00 330e9e46253cbfab178450c976aa90ef0f3ae940 Pull RCU updates from Ingo Molnar: "The sole purpose of these changes is to shrink and simplify the RCU code base, which has suffered from creeping bloat over the past couple of years. The end result is a net removal of ~2700 lines of code: 79 files changed, 1496 insertions(+), 4211 deletions(-) Plus there's a marked reduction in the Kconfig space complexity as well, here's the number of matches on 'grep RCU' in the .config: before after x86-defconfig 17 15 x86-allmodconfig 33 20" * 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (86 commits) rcu: Remove RCU CPU stall warnings from Tiny RCU rcu: Remove event tracing from Tiny RCU rcu: Move RCU debug Kconfig options to kernel/rcu rcu: Move RCU non-debug Kconfig options to kernel/rcu rcu: Eliminate NOCBs CPU-state Kconfig options rcu: Remove debugfs tracing srcu: Remove Classic SRCU srcu: Fix rcutorture-statistics typo rcu: Remove SPARSE_RCU_POINTER Kconfig option rcu: Remove the now-obsolete PROVE_RCU_REPEATEDLY Kconfig option rcu: Remove typecheck() from RCU locking wrapper functions rcu: Remove #ifdef moving rcu_end_inkernel_boot from rcupdate.h rcu: Remove nohz_full full-system-idle state machine rcu: Remove the RCU_KTHREAD_PRIO Kconfig option rcu: Remove *_SLOW_* Kconfig options srcu: Use rnp->lock wrappers to replace explicit memory barriers rcu: Move rnp->lock wrappers for SRCU use rcu: Convert rnp->lock wrappers to macros for SRCU use rcu: Refactor #includes from include/linux/rcupdate.h bcm47xx: Fix build regression ... 
Pull RCU updates from Ingo Molnar:
 "The sole purpose of these changes is to shrink and simplify the RCU
  code base, which has suffered from creeping bloat over the past couple
  of years. The end result is a net removal of ~2700 lines of code:

     79 files changed, 1496 insertions(+), 4211 deletions(-)

  Plus there's a marked reduction in the Kconfig space complexity as
  well, here's the number of matches on 'grep RCU' in the .config:

                               before       after

     x86-defconfig                 17          15
     x86-allmodconfig              33          20"

* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (86 commits)
  rcu: Remove RCU CPU stall warnings from Tiny RCU
  rcu: Remove event tracing from Tiny RCU
  rcu: Move RCU debug Kconfig options to kernel/rcu
  rcu: Move RCU non-debug Kconfig options to kernel/rcu
  rcu: Eliminate NOCBs CPU-state Kconfig options
  rcu: Remove debugfs tracing
  srcu: Remove Classic SRCU
  srcu: Fix rcutorture-statistics typo
  rcu: Remove SPARSE_RCU_POINTER Kconfig option
  rcu: Remove the now-obsolete PROVE_RCU_REPEATEDLY Kconfig option
  rcu: Remove typecheck() from RCU locking wrapper functions
  rcu: Remove #ifdef moving rcu_end_inkernel_boot from rcupdate.h
  rcu: Remove nohz_full full-system-idle state machine
  rcu: Remove the RCU_KTHREAD_PRIO Kconfig option
  rcu: Remove *_SLOW_* Kconfig options
  srcu: Use rnp->lock wrappers to replace explicit memory barriers
  rcu: Move rnp->lock wrappers for SRCU use
  rcu: Convert rnp->lock wrappers to macros for SRCU use
  rcu: Refactor #includes from include/linux/rcupdate.h
  bcm47xx: Fix build regression
  ...
posix_clocks: Use get_itimerspec64() and put_itimerspec64() 2017-06-30T08:15:02+00:00 Deepa Dinamani deepa.kernel@gmail.com 2017-06-24T18:45:08+00:00 725816e8aabb1c183baa2bc9572ab9a0d26b9ea1 Usage of these apis and their compat versions makes the syscalls: timer_settime and timer_gettime and their compat implementations simpler. This patch also serves as a preparatory patch for changing syscalls to use new time_t data types to support the y2038 effort by isolating the processing of user pointers through these apis. Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> 
Usage of these apis and their compat versions makes
the syscalls: timer_settime and timer_gettime and their
compat implementations simpler.

This patch also serves as a preparatory patch for changing
syscalls to use new time_t data types to support the
y2038 effort by isolating the processing of user pointers
through these apis.

Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
nanosleep: Use get_timespec64() and put_timespec64() 2017-06-30T08:14:14+00:00 Deepa Dinamani deepa.kernel@gmail.com 2017-06-24T18:45:06+00:00 c0edd7c9acd0eaee149ab6cb4441cc71a1af87f0 Usage of these apis and their compat versions makes the syscalls: clock_nanosleep and nanosleep and their compat implementations simpler. This is a preparatory patch to isolate data conversions to struct timespec64 at userspace boundaries. This helps contain the changes needed to transition to new y2038 safe types. Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> 
Usage of these apis and their compat versions makes
the syscalls: clock_nanosleep and nanosleep and
their compat implementations simpler.

This is a preparatory patch to isolate data conversions to
struct timespec64 at userspace boundaries. This helps contain
the changes needed to transition to new y2038 safe types.

Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>