diff options
| author | Peter Zijlstra <peterz@infradead.org> | 2015-08-01 19:25:08 +0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2016-05-05 09:23:59 +0200 |
| commit | e7904a28f5331c21d17af638cb477c83662e3cb6 (patch) | |
| tree | 4fd496dcdf41f61964125682664f57d50f3527e2 /kernel/sched/rt.c | |
| parent | eb58075149b7f0300ff19142e6245fe75db2a081 (diff) | |
| download | linux-e7904a28f5331c21d17af638cb477c83662e3cb6.tar.bz2 | |
locking/lockdep, sched/core: Implement a better lock pinning scheme
The problem with the existing lock pinning is that each pin is of
value 1; this mean you can simply unpin if you know its pinned,
without having any extra information.
This scheme generates a random (16 bit) cookie for each pin and
requires this same cookie to unpin. This means you have to keep the
cookie in context.
No objsize difference for !LOCKDEP kernels.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'kernel/sched/rt.c')
| -rw-r--r-- | kernel/sched/rt.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c index 19e13060fcd5..68deaf901a12 100644 --- a/kernel/sched/rt.c +++ b/kernel/sched/rt.c @@ -1524,7 +1524,7 @@ static struct task_struct *_pick_next_task_rt(struct rq *rq) } static struct task_struct * -pick_next_task_rt(struct rq *rq, struct task_struct *prev) +pick_next_task_rt(struct rq *rq, struct task_struct *prev, struct pin_cookie cookie) { struct task_struct *p; struct rt_rq *rt_rq = &rq->rt; @@ -1536,9 +1536,9 @@ pick_next_task_rt(struct rq *rq, struct task_struct *prev) * disabled avoiding further scheduler activity on it and we're * being very careful to re-start the picking loop. */ - lockdep_unpin_lock(&rq->lock); + lockdep_unpin_lock(&rq->lock, cookie); pull_rt_task(rq); - lockdep_pin_lock(&rq->lock); + lockdep_repin_lock(&rq->lock, cookie); /* * pull_rt_task() can drop (and re-acquire) rq->lock; this * means a dl or stop task can slip in, in which case we need |