Re: [PATCH 2/3] drm/scheduler: Don't call wait_event_killable for signaled process.

From: Andrey Grodzovsky
Date: Tue Apr 24 2018 - 11:52:26 EST




On 04/24/2018 11:46 AM, Michel DÃnzer wrote:
Adding the dri-devel list, since this is driver independent code.

Thanks, so many addresses that this one slipped out...


On 2018-04-24 05:30 PM, Andrey Grodzovsky wrote:
Avoid calling wait_event_killable when you are possibly being called
from get_signal routine since in that case you end up in a deadlock
where you are alreay blocked in singla processing any trying to wait
Multiple typos here, "[...] already blocked in signal processing and [...]"?

I don't understand where are the typos.

Andrey



on a new signal.

Signed-off-by: Andrey Grodzovsky <andrey.grodzovsky@xxxxxxx>
---
drivers/gpu/drm/scheduler/gpu_scheduler.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/scheduler/gpu_scheduler.c b/drivers/gpu/drm/scheduler/gpu_scheduler.c
index 088ff2b..09fd258 100644
--- a/drivers/gpu/drm/scheduler/gpu_scheduler.c
+++ b/drivers/gpu/drm/scheduler/gpu_scheduler.c
@@ -227,9 +227,10 @@ void drm_sched_entity_do_release(struct drm_gpu_scheduler *sched,
return;
/**
* The client will not queue more IBs during this fini, consume existing
- * queued IBs or discard them on SIGKILL
+ * queued IBs or discard them when in death signal state since
+ * wait_event_killable can't receive signals in that state.
*/
- if ((current->flags & PF_SIGNALED) && current->exit_code == SIGKILL)
+ if (current->flags & PF_SIGNALED)
entity->fini_status = -ERESTARTSYS;
else
entity->fini_status = wait_event_killable(sched->job_scheduled,