Messages in this thread Patch in this message | | | Date | Sat, 29 Apr 2017 14:45:44 -0700 | From | "Paul E. McKenney" <> | Subject | Re: [patch] timer: Fix timers_update_migration(), and call it in tmigr_init() |
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On Sat, Apr 29, 2017 at 08:20:33PM +0200, Mike Galbraith wrote: > On Sat, 2017-04-29 at 11:06 -0700, Paul E. McKenney wrote: > > > If someone will either repost a fresh series or point me at exactly > > the set of patches to use, I will run it through rcutorture again. > > Patchlet is against x86-tip/master.today.
So today's (as in Saturday April 29) x86-tip/master with the following patch applied?
Thanx, Paul
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timers_update_migration() is called by tick_nohz_activate() before the late initcall tmigr_init() sets tmigr_enabled to true, resulting in it updating neither timer_base.nohz_active nor .migration_enabled, meaning we'll not kick an idling cpu in add_timer_on().
Remove redundant loop avoidance such that tick_nohz_activate() updates timer_bases[].nohz_active as intended, and call it in tmigr_init() to update timer_bases[].migration_enabled.
Signed-off-by: Mike Galbraith <efault@gmx.de> Fixes: ec2206b91d43 timer: Implement the hierarchical pull model --- kernel/time/timer.c | 4 ---- kernel/time/timer_migration.c | 1 + 2 files changed, 1 insertion(+), 4 deletions(-)
--- a/kernel/time/timer.c +++ b/kernel/time/timer.c @@ -224,10 +224,6 @@ void timers_update_migration(bool update bool on = sysctl_timer_migration && tick_nohz_active && tmigr_enabled; unsigned int cpu;
- /* Avoid the loop, if nothing to update */ - if (this_cpu_read(timer_bases[BASE_GLOBAL].migration_enabled) == on) - return; - for_each_possible_cpu(cpu) { per_cpu(timer_bases[BASE_LOCAL].migration_enabled, cpu) = on; per_cpu(timer_bases[BASE_GLOBAL].migration_enabled, cpu) = on; --- a/kernel/time/timer_migration.c +++ b/kernel/time/timer_migration.c @@ -649,6 +649,7 @@ static int __init tmigr_init(void) goto hp_err;
tmigr_enabled = true; + timers_update_migration(false); pr_info("Timer migration: %d hierarchy levels\n", tmigr_hierarchy_levels); return 0;
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