[POWERPC] spufs: use cancel_rearming_delayed_workqueue when stopping spu contexts

The scheduler workqueue may rearm itself and deadlock when we try to stop
it.  Put a flag in place to avoid skip the work if we're tearing down
the context.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
This commit is contained in:
Christoph Hellwig 2007-04-23 21:08:06 +02:00 committed by Arnd Bergmann
parent 390cbb56a7
commit 0887309589
2 changed files with 23 additions and 4 deletions

View File

@ -71,14 +71,25 @@ static inline int node_allowed(int node)
void spu_start_tick(struct spu_context *ctx)
{
if (ctx->policy == SCHED_RR)
if (ctx->policy == SCHED_RR) {
/*
* Make sure the exiting bit is cleared.
*/
clear_bit(SPU_SCHED_EXITING, &ctx->sched_flags);
queue_delayed_work(spu_sched_wq, &ctx->sched_work, SPU_TIMESLICE);
}
}
void spu_stop_tick(struct spu_context *ctx)
{
if (ctx->policy == SCHED_RR)
if (ctx->policy == SCHED_RR) {
/*
* While the work can be rearming normally setting this flag
* makes sure it does not rearm itself anymore.
*/
set_bit(SPU_SCHED_EXITING, &ctx->sched_flags);
cancel_delayed_work(&ctx->sched_work);
}
}
void spu_sched_tick(struct work_struct *work)
@ -88,6 +99,14 @@ void spu_sched_tick(struct work_struct *work)
struct spu *spu;
int rearm = 1;
/*
* If this context is being stopped avoid rescheduling from the
* scheduler tick because we would block on the state_mutex.
* The caller will yield the spu later on anyway.
*/
if (test_bit(SPU_SCHED_EXITING, &ctx->sched_flags))
return;
mutex_lock(&ctx->state_mutex);
spu = ctx->spu;
if (spu) {
@ -377,7 +396,7 @@ static struct spu *find_victim(struct spu_context *ctx)
* @ctx: spu context to schedule
* @flags: flags (currently ignored)
*
* Tries to find a free spu to run @ctx. If no free spu is availble
* Tries to find a free spu to run @ctx. If no free spu is available
* add the context to the runqueue so it gets woken up once an spu
* is available.
*/

View File

@ -41,7 +41,7 @@ struct spu_gang;
/* ctx->sched_flags */
enum {
SPU_SCHED_WAKE = 0, /* currently unused */
SPU_SCHED_EXITING = 0,
};
struct spu_context {