[ANNOUNCE] v4.11.12-rt13

[ANNOUNCE] v4.11.12-rt13

[Sebastian Andrzej Siewior]

Dear RT folks!

I'm pleased to announce the v4.11.12-rt13 patch set. 

Changes since v4.11.12-rt12:

  - Merging Anna-Maria's "hrtimer: Provide softirq context hrtimers"
    series. Merging this series enables the removal of almost all
    hrtimer related patches in the queue. What is left is the "force
    switch" of all timers to the softirq context (except a few special
    ones) and a wait-queue to wait until a timer is completed.
    The overall diffstat compared to -rt12 is
      21 files changed, 573 insertions(+), 651 deletions(-)
    amazing. We have RT wise the same functionality with 78 lines less
    of code.

Known issues
	- There was a report regarding a deadlock within the rtmutex code.

The delta patch against v4.11.12-rt12 is huge can be found here:
 
     https://cdn.kernel.org/pub/linux/kernel/projects/rt/4.11/incr/patch-4.11.12-rt12-rt13.patch.xz
     https://git.kernel.org/rt/linux-rt-devel/d/v4.11.12-rt13/v4.11.12-rt12

You can get this release via the git tree at:

    git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git v4.11.12-rt13

The RT patch against v4.11.12 can be found here:

    https://cdn.kernel.org/pub/linux/kernel/projects/rt/4.11/older/patch-4.11.12-rt13.patch.xz

The split quilt queue is available at:

    https://cdn.kernel.org/pub/linux/kernel/projects/rt/4.11/older/patches-4.11.12-rt13.tar.xz

Sebastian

Re: [ANNOUNCE] v4.11.12-rt13

[Mike Galbraith]

On Tue, 2017-09-05 at 16:52 +0200, Sebastian Andrzej Siewior wrote:
> Dear RT folks!
> 
> I'm pleased to announce the v4.11.12-rt13 patch set. 
> 
> Changes since v4.11.12-rt12:
> 
>   - Merging Anna-Maria's "hrtimer: Provide softirq context hrtimers"
>     series. Merging this series enables the removal of almost all
>     hrtimer related patches in the queue. What is left is the "force
>     switch" of all timers to the softirq context (except a few special
>     ones) and a wait-queue to wait until a timer is completed.
>     The overall diffstat compared to -rt12 is
>       21 files changed, 573 insertions(+), 651 deletions(-)
>     amazing. We have RT wise the same functionality with 78 lines less
>     of code.

(post lazy sod mode [vacation] testing...) 

Seems combo-patch induced some ltp posix conformance test grumbling.

+clock_settime_8_1 ... ... FAILED 
+clock_settime_4_2 ... ... FAILED 
+clock_settime_speculative_4_3 ... ... FAILED 
+timer_settime_5_2 ... ... FAILED 
+timer_settime_5_1 ... ... FAILED 
+timer_settime_5_3 ... ... FAILED 

rtbox:/root # /usr/local/ltp/conformance/interfaces/clock_settime/clock_settime_8-1.run-test
Ended too late.  1507131910 >> 1507131908
Test FAILED
rtbox:/root # /usr/local/ltp/conformance/interfaces/clock_settime/clock_settime_4-2.run-test
timer should have expired _immediately_
rtbox:/root # /usr/local/ltp/conformance/interfaces/clock_settime/speculative/clock_settime_speculative_4-3.run-test
Overrun count =0, not # of repeating timer expirys
FAIL:  Caught 0 signals, not 1
Test FAILED
rtbox:/root # /opt/ltp/conformance/interfaces/timer_settime/timer_settime_5-2.run-test
signal was not sent

Re: [ANNOUNCE] v4.11.12-rt13

[Sebastian Andrzej Siewior]

On 2017-10-04 18:07:59 [+0200], Mike Galbraith wrote:
> Seems combo-patch induced some ltp posix conformance test grumbling.
> 
> +clock_settime_8_1 ... ... FAILED 
> +clock_settime_4_2 ... ... FAILED 
> +clock_settime_speculative_4_3 ... ... FAILED 
> +timer_settime_5_2 ... ... FAILED 
> +timer_settime_5_1 ... ... FAILED 
> +timer_settime_5_3 ... ... FAILED 
> 
> rtbox:/root # /usr/local/ltp/conformance/interfaces/clock_settime/clock_settime_8-1.run-test
> Ended too late.  1507131910 >> 1507131908
> Test FAILED
> rtbox:/root # /usr/local/ltp/conformance/interfaces/clock_settime/clock_settime_4-2.run-test
> timer should have expired _immediately_
> rtbox:/root # /usr/local/ltp/conformance/interfaces/clock_settime/speculative/clock_settime_speculative_4-3.run-test
> Overrun count =0, not # of repeating timer expirys
> FAIL:  Caught 0 signals, not 1
> Test FAILED
> rtbox:/root # /opt/ltp/conformance/interfaces/timer_settime/timer_settime_5-2.run-test
> signal was not sent

So the last triggers here, too and I have an idea.

Sebastian

Re: [ANNOUNCE] v4.11.12-rt13

[Mike Galbraith]

On Thu, 2017-10-05 at 17:54 +0200, Sebastian Andrzej Siewior wrote:
> On 2017-10-04 18:07:59 [+0200], Mike Galbraith wrote:
> > Seems combo-patch induced some ltp posix conformance test grumbling.
> > 
> > +clock_settime_8_1 ... ... FAILED 
> > +clock_settime_4_2 ... ... FAILED 
> > +clock_settime_speculative_4_3 ... ... FAILED 
> > +timer_settime_5_2 ... ... FAILED 
> > +timer_settime_5_1 ... ... FAILED 
> > +timer_settime_5_3 ... ... FAILED 
> > 
> > rtbox:/root # /usr/local/ltp/conformance/interfaces/clock_settime/clock_settime_8-1.run-test
> > Ended too late.  1507131910 >> 1507131908
> > Test FAILED
> > rtbox:/root # /usr/local/ltp/conformance/interfaces/clock_settime/clock_settime_4-2.run-test
> > timer should have expired _immediately_
> > rtbox:/root # /usr/local/ltp/conformance/interfaces/clock_settime/speculative/clock_settime_speculative_4-3.run-test
> > Overrun count =0, not # of repeating timer expirys
> > FAIL:  Caught 0 signals, not 1
> > Test FAILED
> > rtbox:/root # /opt/ltp/conformance/interfaces/timer_settime/timer_settime_5-2.run-test
> > signal was not sent
> 
> So the last triggers here, too and I have an idea.

I ran a trace of clock_settime_4-2.run-test, which arms a timer for
now+9 seconds, then clock_settime to advance 4 seconds past timer
expiration, which should cause the timer to fire.  Going through
SyS_clock_settime..retrigger_next_event..lapic_next_deadline does not
trigger interrupt, but does without the culprit patch applied.

 clock_settime_4-6453  [003] .......   384.288883: SyS_clock_settime <-entry_SYSCALL_64_fastpath
 clock_settime_4-6453  [003] .......   384.288883: __might_fault <-SyS_clock_settime
 clock_settime_4-6453  [003] .......   384.288883: __might_sleep <-__might_fault
 clock_settime_4-6453  [003] .......   384.288883: ___might_sleep <-__might_fault
 clock_settime_4-6453  [003] .......   384.288883: _copy_from_user <-SyS_clock_settime
 clock_settime_4-6453  [003] .......   384.288884: __might_fault <-_copy_from_user
 clock_settime_4-6453  [003] .......   384.288884: __might_sleep <-__might_fault
 clock_settime_4-6453  [003] .......   384.288884: ___might_sleep <-__might_fault
 clock_settime_4-6453  [003] .......   384.288884: posix_clock_realtime_set <-SyS_clock_settime
 clock_settime_4-6453  [003] .......   384.288884: do_sys_settimeofday64 <-posix_clock_realtime_set
 clock_settime_4-6453  [003] .......   384.288884: security_settime64 <-do_sys_settimeofday64
 clock_settime_4-6453  [003] .......   384.288884: cap_settime <-security_settime64
 clock_settime_4-6453  [003] .......   384.288885: capable <-cap_settime
 clock_settime_4-6453  [003] .......   384.288885: ns_capable_common <-cap_settime
 clock_settime_4-6453  [003] .......   384.288885: security_capable <-ns_capable_common
 clock_settime_4-6453  [003] .......   384.288885: cap_capable <-security_capable
 clock_settime_4-6453  [003] .......   384.288885: apparmor_capable <-security_capable
 clock_settime_4-6453  [003] .......   384.288885: do_settimeofday64 <-do_sys_settimeofday64
 clock_settime_4-6453  [003] .......   384.288886: _raw_spin_lock_irqsave <-do_settimeofday64
 clock_settime_4-6453  [003] d......   384.288886: preempt_count_add <-_raw_spin_lock_irqsave
 clock_settime_4-6453  [003] d...1..   384.288886: preempt_count_add <-do_settimeofday64
 clock_settime_4-6453  [003] d...2..   384.288886: timekeeping_forward_now.constprop.12 <-do_settimeofday64
 clock_settime_4-6453  [003] d...2..   384.288886: set_normalized_timespec <-do_settimeofday64
 clock_settime_4-6453  [003] d...2..   384.288886: tk_set_wall_to_mono <-do_settimeofday64
 clock_settime_4-6453  [003] d...2..   384.288886: set_normalized_timespec <-tk_set_wall_to_mono
 clock_settime_4-6453  [003] d...2..   384.288886: set_normalized_timespec <-tk_set_wall_to_mono
 clock_settime_4-6453  [003] d...2..   384.288886: timekeeping_update <-do_settimeofday64
 clock_settime_4-6453  [003] d...2..   384.288887: ntp_clear <-timekeeping_update
 clock_settime_4-6453  [003] d...2..   384.288887: ntp_update_frequency <-ntp_clear
 clock_settime_4-6453  [003] d...2..   384.288887: ntp_get_next_leap <-timekeeping_update
 clock_settime_4-6453  [003] d...2..   384.288887: update_vsyscall <-timekeeping_update
 clock_settime_4-6453  [003] d...2..   384.288887: raw_notifier_call_chain <-timekeeping_update
 clock_settime_4-6453  [003] d...2..   384.288887: notifier_call_chain <-timekeeping_update
 clock_settime_4-6453  [003] d...2..   384.288887: pvclock_gtod_notify <-notifier_call_chain
 clock_settime_4-6453  [003] d...2..   384.288888: preempt_count_add <-pvclock_gtod_notify
 clock_settime_4-6453  [003] d...3..   384.288888: preempt_count_sub <-pvclock_gtod_notify
 clock_settime_4-6453  [003] d...2..   384.288888: update_fast_timekeeper <-timekeeping_update
 clock_settime_4-6453  [003] d...2..   384.288888: update_fast_timekeeper <-timekeeping_update
 clock_settime_4-6453  [003] d...2..   384.288888: preempt_count_sub <-do_settimeofday64
 clock_settime_4-6453  [003] d...1..   384.288888: _raw_spin_unlock_irqrestore <-do_settimeofday64
 clock_settime_4-6453  [003] ....1..   384.288888: preempt_count_sub <-_raw_spin_unlock_irqrestore
 clock_settime_4-6453  [003] .......   384.288888: clock_was_set <-do_settimeofday64
 clock_settime_4-6453  [003] .......   384.288888: on_each_cpu <-clock_was_set
 clock_settime_4-6453  [003] .......   384.288889: preempt_count_add <-on_each_cpu
 clock_settime_4-6453  [003] ....1..   384.288889: smp_call_function <-on_each_cpu
 clock_settime_4-6453  [003] ....1..   384.288889: preempt_count_add <-smp_call_function
 clock_settime_4-6453  [003] ....2..   384.288889: smp_call_function_many <-smp_call_function
 clock_settime_4-6453  [003] ....2..   384.288890: native_send_call_func_ipi <-smp_call_function_many
 clock_settime_4-6453  [003] ....2..   384.288890: x2apic_send_IPI_allbutself <-native_send_call_func_ipi
 clock_settime_4-6453  [003] ....2..   384.288890: __x2apic_send_IPI_mask <-native_send_call_func_ipi
 clock_settime_4-6453  [003] ....2..   384.288914: preempt_count_sub <-smp_call_function
 clock_settime_4-6453  [003] d...1..   384.288914: retrigger_next_event <-on_each_cpu
 clock_settime_4-6453  [003] d...1..   384.288915: _raw_spin_lock <-retrigger_next_event
 clock_settime_4-6453  [003] d...1..   384.288915: preempt_count_add <-_raw_spin_lock
 clock_settime_4-6453  [003] d...2..   384.288915: ktime_get_update_offsets_now <-retrigger_next_event
 clock_settime_4-6453  [003] d...2..   384.288915: __hrtimer_get_next_event <-retrigger_next_event
 clock_settime_4-6453  [003] d...2..   384.288915: __hrtimer_next_event_base <-__hrtimer_get_next_event
 clock_settime_4-6453  [003] d...2..   384.288915: __hrtimer_next_event_base <-retrigger_next_event
 clock_settime_4-6453  [003] d...2..   384.288915: tick_program_event <-retrigger_next_event
 clock_settime_4-6453  [003] d...2..   384.288915: clockevents_program_event <-retrigger_next_event
 clock_settime_4-6453  [003] d...2..   384.288915: ktime_get <-clockevents_program_event
 clock_settime_4-6453  [003] d...2..   384.288916: lapic_next_deadline <-clockevents_program_event
 clock_settime_4-6453  [003] d...2..   384.288916: preempt_count_sub <-retrigger_next_event

Re: [ANNOUNCE] v4.11.12-rt13

[Sebastian Andrzej Siewior]

On 2017-10-06 04:20:31 [+0200], Mike Galbraith wrote:
> On Thu, 2017-10-05 at 17:54 +0200, Sebastian Andrzej Siewior wrote:
> > On 2017-10-04 18:07:59 [+0200], Mike Galbraith wrote:
> > > Seems combo-patch induced some ltp posix conformance test grumbling.
> > > 
> > > +clock_settime_8_1 ... ... FAILED 
> > > +clock_settime_4_2 ... ... FAILED 
> > > +clock_settime_speculative_4_3 ... ... FAILED 
> > > +timer_settime_5_2 ... ... FAILED 
> > > +timer_settime_5_1 ... ... FAILED 
> > > +timer_settime_5_3 ... ... FAILED 
> > > 
> > > rtbox:/root # /usr/local/ltp/conformance/interfaces/clock_settime/clock_settime_8-1.run-test
> > > Ended too late.  1507131910 >> 1507131908
> > > Test FAILED
> > > rtbox:/root # /usr/local/ltp/conformance/interfaces/clock_settime/clock_settime_4-2.run-test
> > > timer should have expired _immediately_
> > > rtbox:/root # /usr/local/ltp/conformance/interfaces/clock_settime/speculative/clock_settime_speculative_4-3.run-test
> > > Overrun count =0, not # of repeating timer expirys
> > > FAIL:  Caught 0 signals, not 1
> > > Test FAILED
> > > rtbox:/root # /opt/ltp/conformance/interfaces/timer_settime/timer_settime_5-2.run-test
> > > signal was not sent
> > 
> > So the last triggers here, too and I have an idea.
> 
> I ran a trace of clock_settime_4-2.run-test, which arms a timer for
> now+9 seconds, then clock_settime to advance 4 seconds past timer
> expiration, which should cause the timer to fire.  Going through
> SyS_clock_settime..retrigger_next_event..lapic_next_deadline does not
> trigger interrupt, but does without the culprit patch applied.

This seems to fix this.

Subject: hrtimer: Update offset for soft bases
From: Anna-Maria Gleixner <anna-maria@linutronix.de>
Date: Fri, 06 Oct 2017 11:28:38 +0200

The offset of the clock bases is done via timekeeping mechanisms. The
offsets of the soft bases has to be considered as well.

Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
---
 kernel/time/hrtimer.c |    8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

--- a/kernel/time/hrtimer.c
+++ b/kernel/time/hrtimer.c
@@ -551,8 +551,14 @@ static inline ktime_t hrtimer_update_bas
 	ktime_t *offs_boot = &base->clock_base[HRTIMER_BASE_BOOTTIME].offset;
 	ktime_t *offs_tai = &base->clock_base[HRTIMER_BASE_TAI].offset;
 
-	return ktime_get_update_offsets_now(&base->clock_was_set_seq,
+	ktime_t now = ktime_get_update_offsets_now(&base->clock_was_set_seq,
 					    offs_real, offs_boot, offs_tai);
+
+	base->clock_base[HRTIMER_BASE_REALTIME_SOFT].offset = *offs_real;
+	base->clock_base[HRTIMER_BASE_BOOTTIME_SOFT].offset = *offs_boot;
+	base->clock_base[HRTIMER_BASE_TAI_SOFT].offset = *offs_tai;
+
+	return now;
 }
 
 /*

Sebastian

Re: [ANNOUNCE] v4.11.12-rt13

[Mike Galbraith]

On Fri, 2017-10-06 at 12:28 +0200, Sebastian Andrzej Siewior wrote:
> On 2017-10-06 04:20:31 [+0200], Mike Galbraith wrote:
> > On Thu, 2017-10-05 at 17:54 +0200, Sebastian Andrzej Siewior wrote:
> > > On 2017-10-04 18:07:59 [+0200], Mike Galbraith wrote:
> > > > Seems combo-patch induced some ltp posix conformance test grumbling.
> > > > 
> > > > +clock_settime_8_1 ... ... FAILED 
> > > > +clock_settime_4_2 ... ... FAILED 
> > > > +clock_settime_speculative_4_3 ... ... FAILED 
> > > > +timer_settime_5_2 ... ... FAILED 
> > > > +timer_settime_5_1 ... ... FAILED 
> > > > +timer_settime_5_3 ... ... FAILED 
> > > > 
> > > > rtbox:/root # /usr/local/ltp/conformance/interfaces/clock_settime/clock_settime_8-1.run-test
> > > > Ended too late.  1507131910 >> 1507131908
> > > > Test FAILED
> > > > rtbox:/root # /usr/local/ltp/conformance/interfaces/clock_settime/clock_settime_4-2.run-test
> > > > timer should have expired _immediately_
> > > > rtbox:/root # /usr/local/ltp/conformance/interfaces/clock_settime/speculative/clock_settime_speculative_4-3.run-test
> > > > Overrun count =0, not # of repeating timer expirys
> > > > FAIL:  Caught 0 signals, not 1
> > > > Test FAILED
> > > > rtbox:/root # /opt/ltp/conformance/interfaces/timer_settime/timer_settime_5-2.run-test
> > > > signal was not sent
> > > 
> > > So the last triggers here, too and I have an idea.
> > 
> > I ran a trace of clock_settime_4-2.run-test, which arms a timer for
> > now+9 seconds, then clock_settime to advance 4 seconds past timer
> > expiration, which should cause the timer to fire.  Going through
> > SyS_clock_settime..retrigger_next_event..lapic_next_deadline does not
> > trigger interrupt, but does without the culprit patch applied.
> 
> This seems to fix this.

Yup, with this, when we get to clockevents_program_event(), we take the
proper if (delta <= 0) path again, and are rewarded with an interrupt.

I'll run full ltp again, make sure there are no new failure deltas.

> Subject: hrtimer: Update offset for soft bases
> From: Anna-Maria Gleixner <anna-maria@linutronix.de>
> Date: Fri, 06 Oct 2017 11:28:38 +0200
> 
> The offset of the clock bases is done via timekeeping mechanisms. The
> offsets of the soft bases has to be considered as well.
> 
> Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
> ---
>  kernel/time/hrtimer.c |    8 +++++++-
>  1 file changed, 7 insertions(+), 1 deletion(-)
> 
> --- a/kernel/time/hrtimer.c
> +++ b/kernel/time/hrtimer.c
> @@ -551,8 +551,14 @@ static inline ktime_t hrtimer_update_bas
>  	ktime_t *offs_boot = &base->clock_base[HRTIMER_BASE_BOOTTIME].offset;
>  	ktime_t *offs_tai = &base->clock_base[HRTIMER_BASE_TAI].offset;
>  
> -	return ktime_get_update_offsets_now(&base->clock_was_set_seq,
> +	ktime_t now = ktime_get_update_offsets_now(&base->clock_was_set_seq,
>  					    offs_real, offs_boot, offs_tai);
> +
> +	base->clock_base[HRTIMER_BASE_REALTIME_SOFT].offset = *offs_real;
> +	base->clock_base[HRTIMER_BASE_BOOTTIME_SOFT].offset = *offs_boot;
> +	base->clock_base[HRTIMER_BASE_TAI_SOFT].offset = *offs_tai;
> +
> +	return now;
>  }
>  
>  /*
> 
> Sebastian

Re: [ANNOUNCE] v4.11.12-rt13

[Mike Galbraith]

On Fri, 2017-10-06 at 15:33 +0200, Mike Galbraith wrote:
> 
> I'll run full ltp again, make sure there are no new failure deltas.

Haven't done that yet, but I have checked all of the reported failures.

time-hrtimer:-Use-softirq-based-wakeups-for-non-RT-threads.patch fixes
clock_settime_8-1.run-test, hrtimer:-Update-offset-for-soft-bases.patch 
fixes the rest.

However...

homer:..debug/tracing # /usr/local/ltp/conformance/interfaces/clock_settime/clock_settime_8-1.run-test
Test PASSED
homer:..debug/tracing # chrt -f 1 /usr/local/ltp/conformance/interfaces/clock_settime/clock_settime_8-1.run-test
Ended too late.  1507308976 >> 1507308974
Test FAILED

That's a bit troubling.  No earlier kernel, rt or not, cares about
policy.  Either now getting a NAK is less than wonderful, but
SCHED_FIFO gets a NAK while SCHED_OTHER walks away with an ACK?

	-Mike

Re: [ANNOUNCE] v4.11.12-rt13

[Mike Galbraith]

On Fri, 2017-10-06 at 19:38 +0200, Mike Galbraith wrote:
> On Fri, 2017-10-06 at 15:33 +0200, Mike Galbraith wrote:
> > 
> > I'll run full ltp again, make sure there are no new failure deltas.
> 
> Haven't done that yet, but I have checked all of the reported failures.
> 
> time-hrtimer:-Use-softirq-based-wakeups-for-non-RT-threads.patch fixes
> clock_settime_8-1.run-test, hrtimer:-Update-offset-for-soft-bases.patch 
> fixes the rest.
> 
> However...

testcases/open_posix_testsuite/conformance/interfaces/clock_settime/8-1.c:
 * Steps:
 * - get time T0
 * - in child:  set clock_nanosleep() to sleep for SLEEPSEC seconds
 * - in parent:  sleep SMALLTIME (< SLEEPSEC)
 * - in parent:  set time back to T0
 * - in child:  ensure time when clock_nanosleep() expires is within
 *   ACCEPTABLEDELTA of T0+(SLEEPSEC-SMALLTIME)
...
#define SLEEPSEC 5
#define SMALLTIME 2
#define ACCEPTABLEDELTA 1

homer:..debug/tracing # time chrt -o 0 /usr/local/ltp/conformance/interfaces/clock_settime/clock_settime_8-1.run-test
Test PASSED

real    0m5.002s
user    0m0.000s
sys     0m0.001s
homer:..debug/tracing # time chrt -f 1 /usr/local/ltp/conformance/interfaces/clock_settime/clock_settime_8-1.run-test
Ended too late.  1507351636 >> 1507351634
Test FAILED

real    0m7.002s
user    0m0.000s
sys     0m0.002s

Re: [ANNOUNCE] v4.11.12-rt13

[Sebastian Andrzej Siewior]

On 2017-10-07 06:50:53 [+0200], Mike Galbraith wrote:
> > However...
> 
> testcases/open_posix_testsuite/conformance/interfaces/clock_settime/8-1.c:
>  * Steps:
>  * - get time T0
>  * - in child:  set clock_nanosleep() to sleep for SLEEPSEC seconds
>  * - in parent:  sleep SMALLTIME (< SLEEPSEC)
>  * - in parent:  set time back to T0
>  * - in child:  ensure time when clock_nanosleep() expires is within
>  *   ACCEPTABLEDELTA of T0+(SLEEPSEC-SMALLTIME)
> ...
> #define SLEEPSEC 5
> #define SMALLTIME 2
> #define ACCEPTABLEDELTA 1
> 
> homer:..debug/tracing # time chrt -o 0 /usr/local/ltp/conformance/interfaces/clock_settime/clock_settime_8-1.run-test
> Test PASSED
> 
> real    0m5.002s
> user    0m0.000s
> sys     0m0.001s
> homer:..debug/tracing # time chrt -f 1 /usr/local/ltp/conformance/interfaces/clock_settime/clock_settime_8-1.run-test
> Ended too late.  1507351636 >> 1507351634
> Test FAILED
> 
> real    0m7.002s
> user    0m0.000s
> sys     0m0.002s

As per POSIX we should sleep only 5 secs despite the CLOCK_REALTIME
change. In RT case however we sleep 7 so we somehow account it which is
wrong.

Sebastian

Re: [ANNOUNCE] v4.11.12-rt13

[Sebastian Andrzej Siewior]

On 2017-10-10 18:24:55 [+0200], To Mike Galbraith wrote:
> > homer:..debug/tracing # time chrt -f 1 /usr/local/ltp/conformance/interfaces/clock_settime/clock_settime_8-1.run-test
> > Ended too late.  1507351636 >> 1507351634
> > Test FAILED
> > 
> > real    0m7.002s
> > user    0m0.000s
> > sys     0m0.002s
> 
> As per POSIX we should sleep only 5 secs despite the CLOCK_REALTIME
> change. In RT case however we sleep 7 so we somehow account it which is
> wrong.

This should cure it:

diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c
--- a/kernel/time/hrtimer.c
+++ b/kernel/time/hrtimer.c
@@ -1258,6 +1258,8 @@ static void __hrtimer_init(struct hrtimer *timer, clockid_t clock_id,
 			clock_id = CLOCK_MONOTONIC;
 		else if (clock_id == CLOCK_REALTIME_SOFT)
 			clock_id = CLOCK_MONOTONIC_SOFT;
+		else if (clock_id == CLOCK_REALTIME_HARD)
+			clock_id = CLOCK_MONOTONIC;
 	}
 
 	base = hrtimer_clockid_to_base(clock_id);
 
Sebastian

Re: [ANNOUNCE] v4.11.12-rt13

[Mike Galbraith]

On Tue, 2017-10-10 at 18:47 +0200, Sebastian Andrzej Siewior wrote:
> On 2017-10-10 18:24:55 [+0200], To Mike Galbraith wrote:
> > > homer:..debug/tracing # time chrt -f 1 /usr/local/ltp/conformance/interfaces/clock_settime/clock_settime_8-1.run-test
> > > Ended too late.  1507351636 >> 1507351634
> > > Test FAILED
> > > 
> > > real    0m7.002s
> > > user    0m0.000s
> > > sys     0m0.002s
> > 
> > As per POSIX we should sleep only 5 secs despite the CLOCK_REALTIME
> > change. In RT case however we sleep 7 so we somehow account it which is
> > wrong.
> 
> This should cure it:

Yup, nailed it.  I hadn't gotten around to chasing this one (4 weeks
vacation === baaaackloooog), but did do the promised full ltp run with
fixes applied, and there were no shiny new failures.  So tree should
now be perfect.. modulo the pile of bugs nobody has as yet noticed :)

> diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c
> --- a/kernel/time/hrtimer.c
> +++ b/kernel/time/hrtimer.c
> @@ -1258,6 +1258,8 @@ static void __hrtimer_init(struct hrtimer *timer, clockid_t clock_id,
>  			clock_id = CLOCK_MONOTONIC;
>  		else if (clock_id == CLOCK_REALTIME_SOFT)
>  			clock_id = CLOCK_MONOTONIC_SOFT;
> +		else if (clock_id == CLOCK_REALTIME_HARD)
> +			clock_id = CLOCK_MONOTONIC;
>  	}
>  
>  	base = hrtimer_clockid_to_base(clock_id);
>  
> Sebastian