From 3bed5e2166a5e433bf62162f3cd3c5174d335934 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Mon, 3 Oct 2016 16:35:32 +0200 Subject: [PATCH] sched/core: Add missing update_rq_clock() call for task_hot() Add the update_rq_clock() call at the top of the callstack instead of at the bottom where we find it missing, this to aid later effort to minimize the number of update_rq_lock() calls. WARNING: CPU: 30 PID: 194 at ../kernel/sched/sched.h:797 assert_clock_updated() rq->clock_update_flags < RQCF_ACT_SKIP Call Trace: dump_stack() __warn() warn_slowpath_fmt() assert_clock_updated.isra.63.part.64() can_migrate_task() load_balance() pick_next_task_fair() __schedule() schedule() worker_thread() kthread() Signed-off-by: Peter Zijlstra (Intel) Cc: Linus Torvalds Cc: Mike Galbraith Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar --- kernel/sched/fair.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 972b67622922..b3bfe3fb4e13 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -8070,6 +8070,7 @@ redo: more_balance: raw_spin_lock_irqsave(&busiest->lock, flags); + update_rq_clock(busiest); /* * cur_ld_moved - load moved in current iteration @@ -8446,6 +8447,7 @@ static int active_load_balance_cpu_stop(void *data) }; schedstat_inc(sd->alb_count); + update_rq_clock(busiest_rq); p = detach_one_task(&env); if (p) {