diff options
| author | Olav Haugan <ohaugan@codeaurora.org> | 2016-11-27 19:17:28 -0800 |
|---|---|---|
| committer | Olav Haugan <ohaugan@codeaurora.org> | 2016-11-28 11:00:29 -0800 |
| commit | e5c095a2c715f7dd1ac71194db5cb5bc2e98ab19 (patch) | |
| tree | 8339427847034aa97d4f48fd5b4551995c0b66e9 | |
| parent | 841264c5051b8cbd44b2e1b12db94f8cbcd0c43a (diff) | |
sched/core: Do not free task while holding rq lock
Clearing the hmp request can cause a task to be freed. When a task is
freed the free call might wake up a kworker which will cause a
spinlock lockup (rq lock). Fix this by avoiding calling put_task_struct
when holding the rq lock.
In addition move call to clear_hmp_request out of stopper thread context
since it is not necessary to do this on the cpu being isolated.
Change-Id: Ie577db4701a88849560df385869ff7cf73695a05
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
| -rw-r--r-- | kernel/sched/core.c | 2 | ||||
| -rw-r--r-- | kernel/sched/hmp.c | 6 |
2 files changed, 6 insertions, 2 deletions
diff --git a/kernel/sched/core.c b/kernel/sched/core.c index a5d101e8a5f2..e60093ea6d68 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -5600,7 +5600,6 @@ int do_isolation_work_cpu_stop(void *data) */ nohz_balance_clear_nohz_mask(cpu); - clear_hmp_request(cpu); local_irq_enable(); return 0; } @@ -5725,6 +5724,7 @@ int sched_isolate_cpu(int cpu) migrate_sync_cpu(cpu, cpumask_first(&avail_cpus)); stop_cpus(cpumask_of(cpu), do_isolation_work_cpu_stop, 0); + clear_hmp_request(cpu); calc_load_migrate(rq); update_max_interval(); diff --git a/kernel/sched/hmp.c b/kernel/sched/hmp.c index 968a41e0e81e..a9ccb63c8e23 100644 --- a/kernel/sched/hmp.c +++ b/kernel/sched/hmp.c @@ -641,14 +641,18 @@ void clear_hmp_request(int cpu) clear_boost_kick(cpu); clear_reserved(cpu); if (rq->push_task) { + struct task_struct *push_task = NULL; + raw_spin_lock_irqsave(&rq->lock, flags); if (rq->push_task) { clear_reserved(rq->push_cpu); - put_task_struct(rq->push_task); + push_task = rq->push_task; rq->push_task = NULL; } rq->active_balance = 0; raw_spin_unlock_irqrestore(&rq->lock, flags); + if (push_task) + put_task_struct(push_task); } } |