diff options
Diffstat (limited to 'kernel/sched/core.c')
| -rw-r--r-- | kernel/sched/core.c | 25 |
1 files changed, 25 insertions, 0 deletions
diff --git a/kernel/sched/core.c b/kernel/sched/core.c index cb55d4247e65..a0b11201a7b4 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -6654,6 +6654,23 @@ find_proxy_task(struct rq *rq, struct task_struct *donor, struct rq_flags *rf) } #endif /* SCHED_PROXY_EXEC */ +static inline void proxy_tag_curr(struct rq *rq, struct task_struct *owner) +{ + if (!sched_proxy_exec()) + return; + /* + * pick_next_task() calls set_next_task() on the chosen task + * at some point, which ensures it is not push/pullable. + * However, the chosen/donor task *and* the mutex owner form an + * atomic pair wrt push/pull. + * + * Make sure owner we run is not pushable. Unfortunately we can + * only deal with that by means of a dequeue/enqueue cycle. :-/ + */ + dequeue_task(rq, owner, DEQUEUE_NOCLOCK | DEQUEUE_SAVE); + enqueue_task(rq, owner, ENQUEUE_NOCLOCK | ENQUEUE_RESTORE); +} + /* * __schedule() is the main scheduler function. * @@ -6798,6 +6815,10 @@ picked: * changes to task_struct made by pick_next_task(). */ RCU_INIT_POINTER(rq->curr, next); + + if (!task_current_donor(rq, next)) + proxy_tag_curr(rq, next); + /* * The membarrier system call requires each architecture * to have a full memory barrier after updating @@ -6832,6 +6853,10 @@ picked: /* Also unlocks the rq: */ rq = context_switch(rq, prev, next, &rf); } else { + /* In case next was already curr but just got blocked_donor */ + if (!task_current_donor(rq, next)) + proxy_tag_curr(rq, next); + rq_unpin_lock(rq, &rf); __balance_callbacks(rq); raw_spin_rq_unlock_irq(rq); |