Revision 2548d546d40c0014efdde88a53bf7896e917dcce authored by Peter Zijlstra on 21 April 2016, 16:03:15 UTC, committed by Ingo Molnar on 28 April 2016, 08:28:55 UTC
Chris Metcalf reported a that sched_can_stop_tick() sometimes fails to re-enable the tick. His observed problem is that rq->cfs.nr_running can be 1 even though there are multiple runnable CFS tasks. This happens in the cgroup case, in which case cfs.nr_running is the number of runnable entities for that level. If there is a single runnable cgroup (which can have an arbitrary number of runnable child entries itself) rq->cfs.nr_running will be 1. However, looking at that function I think there's more problems with it. It seems to assume that if there's FIFO tasks, those will run. This is incorrect. The FIFO task can have a lower prio than an RR task, in which case the RR task will run. So the whole fifo_nr_running test seems misplaced, it should go after the rr_nr_running tests. That is, only if !rr_nr_running, can we use fifo_nr_running like this. Reported-by: Chris Metcalf <cmetcalf@mellanox.com> Tested-by: Chris Metcalf <cmetcalf@mellanox.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Christoph Lameter <cl@linux.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Luiz Capitulino <lcapitulino@redhat.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: Viresh Kumar <viresh.kumar@linaro.org> Cc: Wanpeng Li <kernellwp@gmail.com> Fixes: 76d92ac305f2 ("sched: Migrate sched to use new tick dependency mask model") Link: http://lkml.kernel.org/r/20160421160315.GK24771@twins.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
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dmasound | ||
.gitignore | -rw-r--r-- | 47 bytes |
CHANGELOG | -rw-r--r-- | 13.4 KB |
Kconfig | -rw-r--r-- | 19.1 KB |
Makefile | -rw-r--r-- | 3.3 KB |
README.FIRST | -rw-r--r-- | 246 bytes |
ad1848.c | -rw-r--r-- | 74.2 KB |
ad1848.h | -rw-r--r-- | 982 bytes |
ad1848_mixer.h | -rw-r--r-- | 10.7 KB |
aedsp16.c | -rw-r--r-- | 35.6 KB |
audio.c | -rw-r--r-- | 25.0 KB |
bin2hex.c | -rw-r--r-- | 755 bytes |
coproc.h | -rw-r--r-- | 361 bytes |
dev_table.c | -rw-r--r-- | 5.5 KB |
dev_table.h | -rw-r--r-- | 10.6 KB |
dmabuf.c | -rw-r--r-- | 34.9 KB |
hex2hex.c | -rw-r--r-- | 1.9 KB |
kahlua.c | -rw-r--r-- | 4.9 KB |
midi_ctrl.h | -rw-r--r-- | 1.0 KB |
midi_synth.c | -rw-r--r-- | 14.8 KB |
midi_synth.h | -rw-r--r-- | 1.7 KB |
midibuf.c | -rw-r--r-- | 8.6 KB |
mpu401.c | -rw-r--r-- | 37.6 KB |
mpu401.h | -rw-r--r-- | 419 bytes |
msnd.c | -rw-r--r-- | 8.2 KB |
msnd.h | -rw-r--r-- | 7.2 KB |
msnd_classic.c | -rw-r--r-- | 122 bytes |
msnd_classic.h | -rw-r--r-- | 5.3 KB |
msnd_pinnacle.c | -rw-r--r-- | 47.5 KB |
msnd_pinnacle.h | -rw-r--r-- | 7.4 KB |
opl3.c | -rw-r--r-- | 27.0 KB |
opl3_hw.h | -rw-r--r-- | 6.9 KB |
os.h | -rw-r--r-- | 942 bytes |
pas2.h | -rw-r--r-- | 500 bytes |
pas2_card.c | -rw-r--r-- | 9.4 KB |
pas2_midi.c | -rw-r--r-- | 4.9 KB |
pas2_mixer.c | -rw-r--r-- | 7.8 KB |
pas2_pcm.c | -rw-r--r-- | 8.7 KB |
pss.c | -rw-r--r-- | 32.3 KB |
sb.h | -rw-r--r-- | 5.2 KB |
sb_audio.c | -rw-r--r-- | 26.6 KB |
sb_card.c | -rw-r--r-- | 9.7 KB |
sb_card.h | -rw-r--r-- | 5.7 KB |
sb_common.c | -rw-r--r-- | 28.9 KB |
sb_ess.c | -rw-r--r-- | 51.2 KB |
sb_ess.h | -rw-r--r-- | 887 bytes |
sb_midi.c | -rw-r--r-- | 4.2 KB |
sb_mixer.c | -rw-r--r-- | 19.3 KB |
sb_mixer.h | -rw-r--r-- | 2.1 KB |
sequencer.c | -rw-r--r-- | 33.4 KB |
sleep.h | -rw-r--r-- | 464 bytes |
sound_calls.h | -rw-r--r-- | 3.4 KB |
sound_config.h | -rw-r--r-- | 3.1 KB |
sound_firmware.h | -rw-r--r-- | 58 bytes |
sound_timer.c | -rw-r--r-- | 6.1 KB |
soundcard.c | -rw-r--r-- | 16.4 KB |
soundvers.h | -rw-r--r-- | 86 bytes |
swarm_cs4297a.c | -rw-r--r-- | 88.4 KB |
sys_timer.c | -rw-r--r-- | 5.2 KB |
trix.c | -rw-r--r-- | 10.9 KB |
tuning.h | -rw-r--r-- | 1.1 KB |
uart401.c | -rw-r--r-- | 10.4 KB |
uart6850.c | -rw-r--r-- | 7.1 KB |
ulaw.h | -rw-r--r-- | 3.2 KB |
v_midi.c | -rw-r--r-- | 6.3 KB |
v_midi.h | -rw-r--r-- | 281 bytes |
vidc.c | -rw-r--r-- | 12.1 KB |
vidc.h | -rw-r--r-- | 1.8 KB |
vidc_fill.S | -rw-r--r-- | 4.3 KB |
waveartist.c | -rw-r--r-- | 46.6 KB |
waveartist.h | -rw-r--r-- | 2.3 KB |
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