diff options
author | Deepak Nibade <dnibade@nvidia.com> | 2014-07-03 09:02:20 -0400 |
---|---|---|
committer | Dan Willemsen <dwillemsen@nvidia.com> | 2015-03-18 15:10:24 -0400 |
commit | 7c5404fa426c6f38b8330b2f70db552e1bfaba72 (patch) | |
tree | 9dedd18f2e1cdac3f1a151aad794f2a43e40d2c9 /drivers/gpu/nvgpu/gk20a/channel_gk20a.c | |
parent | 0b1f9e427205190dc5e651f78ff7f8be8641037e (diff) |
gpu: nvgpu: remove redundant busy()/idle() calls
gk20a_busy() call in channel_syncpt_incr() and corresponding
gk20a_idle() call in channel_update() are redundant since they
are already encapsulated inside another pair of busy/idle calls
This busy/idle pair will be called only from submit_gpfifo()
and submit_gpfifo() already has its own busy/idle which it
preserves for whole path and hence this redundant pair can be
removed
Also, this prevents a dead lock scenario while do_idle() is in
progress as follows :
- in submit_gpfifo() we call first gk20a_busy() which acquires
busy read semaphore
- in do_idle() we acquire busy write semaphore and wait for
current jobs to finish
- now submit_gpfifo() encounters second gk20a_busy() and requests
busy read semaphore again
- this results in dead lock where do_idle() is waiting for
submit_gpfifo() to complete and submit_gpfifo() is waiting for
busy lock held by do_idle() and hence it cannot complete
bug 1529160
Change-Id: I96e4368352f693e93524f0f61689b4447e5331ea
Signed-off-by: Deepak Nibade <dnibade@nvidia.com>
Reviewed-on: http://git-master/r/434191
(cherry picked from commit c4315c6caa42bab72ba6017c7ded25f4e9363dec)
Reviewed-on: http://git-master/r/435132
Reviewed-by: Sachin Nikam <snikam@nvidia.com>
Tested-by: Sachin Nikam <snikam@nvidia.com>
Diffstat (limited to 'drivers/gpu/nvgpu/gk20a/channel_gk20a.c')
-rw-r--r-- | drivers/gpu/nvgpu/gk20a/channel_gk20a.c | 7 |
1 files changed, 1 insertions, 6 deletions
diff --git a/drivers/gpu/nvgpu/gk20a/channel_gk20a.c b/drivers/gpu/nvgpu/gk20a/channel_gk20a.c index 78e52c62..c43798b5 100644 --- a/drivers/gpu/nvgpu/gk20a/channel_gk20a.c +++ b/drivers/gpu/nvgpu/gk20a/channel_gk20a.c | |||
@@ -1414,10 +1414,8 @@ static int gk20a_channel_add_job(struct channel_gk20a *c, | |||
1414 | 1414 | ||
1415 | void gk20a_channel_update(struct channel_gk20a *c, int nr_completed) | 1415 | void gk20a_channel_update(struct channel_gk20a *c, int nr_completed) |
1416 | { | 1416 | { |
1417 | struct gk20a *g = c->g; | ||
1418 | struct vm_gk20a *vm = c->vm; | 1417 | struct vm_gk20a *vm = c->vm; |
1419 | struct channel_gk20a_job *job, *n; | 1418 | struct channel_gk20a_job *job, *n; |
1420 | int i; | ||
1421 | 1419 | ||
1422 | wake_up(&c->submit_wq); | 1420 | wake_up(&c->submit_wq); |
1423 | 1421 | ||
@@ -1442,7 +1440,7 @@ void gk20a_channel_update(struct channel_gk20a *c, int nr_completed) | |||
1442 | 1440 | ||
1443 | list_del_init(&job->list); | 1441 | list_del_init(&job->list); |
1444 | kfree(job); | 1442 | kfree(job); |
1445 | gk20a_idle(g->dev); | 1443 | gk20a_idle(c->g->dev); |
1446 | } | 1444 | } |
1447 | 1445 | ||
1448 | /* | 1446 | /* |
@@ -1460,9 +1458,6 @@ void gk20a_channel_update(struct channel_gk20a *c, int nr_completed) | |||
1460 | } | 1458 | } |
1461 | mutex_unlock(&c->jobs_lock); | 1459 | mutex_unlock(&c->jobs_lock); |
1462 | mutex_unlock(&c->submit_lock); | 1460 | mutex_unlock(&c->submit_lock); |
1463 | |||
1464 | for (i = 0; i < nr_completed; i++) | ||
1465 | gk20a_idle(c->g->dev); | ||
1466 | } | 1461 | } |
1467 | 1462 | ||
1468 | void add_wait_cmd(u32 *ptr, u32 id, u32 thresh) | 1463 | void add_wait_cmd(u32 *ptr, u32 id, u32 thresh) |