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| author |   Valentin Schneider <valentin.schneider@arm.com> | 2019-07-15 11:25:07 +0100 |
|---|---|---|
| committer |   Ingo Molnar <mingo@kernel.org> | 2019-07-25 15:51:51 +0200 |
| commit | b34920d4ce6e6fc9424c20a4be98676eb543122f (patch) | |
| tree | c6292e5bb17d82ae7d3929e11f07a6732b03f79a /kernel/sched/fair.c | |
| parent | sched/fair: Move init_numa_balancing() below task_numa_work() (diff) | |
| download | wireguard-linux-b34920d4ce6e6fc9424c20a4be98676eb543122f.tar.xz wireguard-linux-b34920d4ce6e6fc9424c20a4be98676eb543122f.zip | |
sched/fair: Move task_numa_work() init to init_numa_balancing()
We only need to set the callback_head worker function once, do it
during sched_fork().
While at it, move the comment regarding double task_work addition to
init_numa_balancing(), since the double add sentinel is first set there.
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: mgorman@suse.de
Cc: riel@surriel.com
Link: https://lkml.kernel.org/r/20190715102508.32434-3-valentin.schneider@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'kernel/sched/fair.c')
| -rw-r--r-- | kernel/sched/fair.c | 9 |
1 files changed, 5 insertions, 4 deletions
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index f0c488015649..fd391fc00ed8 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -2495,7 +2495,7 @@ void task_numa_work(struct callback_head *work) SCHED_WARN_ON(p != container_of(work, struct task_struct, numa_work)); - work->next = work; /* protect against double add */ + work->next = work; /* * Who cares about NUMA placement when they're dying. * @@ -2639,12 +2639,15 @@ void init_numa_balancing(unsigned long clone_flags, struct task_struct *p) p->node_stamp = 0; p->numa_scan_seq = mm ? mm->numa_scan_seq : 0; p->numa_scan_period = sysctl_numa_balancing_scan_delay; + /* Protect against double add, see task_tick_numa and task_numa_work */ p->numa_work.next = &p->numa_work; p->numa_faults = NULL; RCU_INIT_POINTER(p->numa_group, NULL); p->last_task_numa_placement = 0; p->last_sum_exec_runtime = 0; + init_task_work(&p->numa_work, task_numa_work); + /* New address space, reset the preferred nid */ if (!(clone_flags & CLONE_VM)) { p->numa_preferred_nid = NUMA_NO_NODE; @@ -2693,10 +2696,8 @@ static void task_tick_numa(struct rq *rq, struct task_struct *curr) curr->numa_scan_period = task_scan_start(curr); curr->node_stamp += period; - if (!time_before(jiffies, curr->mm->numa_next_scan)) { - init_task_work(work, task_numa_work); /* TODO: move this into sched_fork() */ + if (!time_before(jiffies, curr->mm->numa_next_scan)) task_work_add(curr, work, true); - } } } |