From a53ce18cacb477dd0513c607f187d16f0fa96f71 Mon Sep 17 00:00:00 2001 From: Vincent Guittot Date: Fri, 17 Mar 2023 17:08:10 +0100 Subject: sched/fair: Sanitize vruntime of entity being migrated Commit 829c1651e9c4 ("sched/fair: sanitize vruntime of entity being placed") fixes an overflowing bug, but ignore a case that se->exec_start is reset after a migration. For fixing this case, we delay the reset of se->exec_start after placing the entity which se->exec_start to detect long sleeping task. In order to take into account a possible divergence between the clock_task of 2 rqs, we increase the threshold to around 104 days. Fixes: 829c1651e9c4 ("sched/fair: sanitize vruntime of entity being placed") Originally-by: Zhang Qiao Signed-off-by: Vincent Guittot Signed-off-by: Peter Zijlstra (Intel) Tested-by: Zhang Qiao Link: https://lore.kernel.org/r/20230317160810.107988-1-vincent.guittot@linaro.org --- kernel/sched/core.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'kernel/sched/core.c') diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 488655f2319f..0d18c3969f90 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -2084,6 +2084,9 @@ static inline void dequeue_task(struct rq *rq, struct task_struct *p, int flags) void activate_task(struct rq *rq, struct task_struct *p, int flags) { + if (task_on_rq_migrating(p)) + flags |= ENQUEUE_MIGRATED; + enqueue_task(rq, p, flags); p->on_rq = TASK_ON_RQ_QUEUED; -- cgit v1.2.3