linux-stable/kernel/sched
Peter Zijlstra ae79270232 sched: Optimize finish_lock_switch()
The kernel test robot measured a -1.6% performance regression on
will-it-scale/sched_yield due to commit:

  2558aacff8 ("sched/hotplug: Ensure only per-cpu kthreads run during hotplug")

Even though we were careful to replace a single load with another
single load from the same cacheline.

Restore finish_lock_switch() to the exact state before the offending
patch and solve the problem differently.

Fixes: 2558aacff8 ("sched/hotplug: Ensure only per-cpu kthreads run during hotplug")
Reported-by: kernel test robot <oliver.sang@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20201210161408.GX3021@hirez.programming.kicks-ass.net
2020-12-15 11:27:53 +01:00
..
autogroup.c sched/autogroup: Make autogroup_path() always available 2019-06-24 19:23:40 +02:00
autogroup.h
clock.c sched/clock: Use static_branch_likely() with sched_clock_running 2019-11-29 08:10:54 +01:00
completion.c completion: Use lockdep_assert_RT_in_threaded_ctx() in complete_all() 2020-03-23 18:40:25 +01:00
core.c sched: Optimize finish_lock_switch() 2020-12-15 11:27:53 +01:00
cpuacct.c sched/cpuacct: Fix charge cpuacct.usage_sys 2020-05-19 20:34:14 +02:00
cpudeadline.c sched,rt: Use the full cpumask for balancing 2020-11-10 18:39:00 +01:00
cpudeadline.h
cpufreq.c cpufreq: Avoid leaving stale IRQ work items during CPU offline 2019-12-12 17:59:43 +01:00
cpufreq_schedutil.c Merge branch 'linus' into sched/core, to resolve semantic conflict 2020-11-27 11:10:50 +01:00
cpupri.c Merge branch 'sched/migrate-disable' 2020-11-10 18:39:04 +01:00
cpupri.h sched/cpupri: Add CPUPRI_HIGHER 2020-10-29 11:00:30 +01:00
cputime.c sched/cputime: Improve cputime_adjust() 2020-06-15 14:10:00 +02:00
deadline.c Merge branch 'linus' into sched/core, to resolve semantic conflict 2020-11-27 11:10:50 +01:00
debug.c sched/debug: Fix memory corruption caused by multiple small reads of flags 2020-11-10 18:38:49 +01:00
fair.c sched/fair: Trivial correction of the newidle_balance() comment 2020-12-11 10:30:44 +01:00
features.h sched/rt: Disable RT_RUNTIME_SHARE by default 2020-09-25 14:23:24 +02:00
idle.c sched: Remove select_task_rq()'s sd_flag parameter 2020-11-10 18:39:06 +01:00
isolation.c isolcpus: Affine unbound kernel threads to housekeeping cpus 2020-06-15 14:10:03 +02:00
loadavg.c sched: nohz: stop passing around unused "ticks" parameter. 2020-07-22 10:22:04 +02:00
Makefile kcsan: Improve various small stylistic details 2019-11-20 10:47:23 +01:00
membarrier.c sched: membarrier: document memory ordering scenarios 2020-10-29 11:00:31 +01:00
pelt.c sched: Add a tracepoint to track rq->nr_running 2020-07-08 11:39:02 +02:00
pelt.h sched/pelt: Cleanup PELT divider 2020-06-15 14:10:06 +02:00
psi.c sched,psi: Convert to sched_set_fifo_low() 2020-06-15 14:10:25 +02:00
rt.c sched: Remove select_task_rq()'s sd_flag parameter 2020-11-10 18:39:06 +01:00
sched-pelt.h sched/fair: Fix "runnable_avg_yN_inv" not used warnings 2019-06-17 12:15:58 +02:00
sched.h sched: Optimize finish_lock_switch() 2020-12-15 11:27:53 +01:00
smp.h sched/headers: Split out open-coded prototypes into kernel/sched/smp.h 2020-05-28 11:03:20 +02:00
stats.c proc: introduce proc_create_seq{,_data} 2018-05-16 07:23:35 +02:00
stats.h psi: Move PF_MEMSTALL out of task->flags 2020-03-20 13:06:19 +01:00
stop_task.c sched: Remove select_task_rq()'s sd_flag parameter 2020-11-10 18:39:06 +01:00
swait.c sched/swait: Prepare usage in completions 2020-03-21 16:00:23 +01:00
topology.c sched/topology: Condition EAS enablement on FIE support 2020-11-19 11:25:47 +01:00
wait.c list: add "list_del_init_careful()" to go with "list_empty_careful()" 2020-08-02 20:39:44 -07:00
wait_bit.c sched/wait: fix ___wait_var_event(exclusive) 2019-12-17 13:32:50 +01:00