gpu: nvgpu: gk20a: Use spin_lock for jobs_lock

This is done to boost performance of the GPU submit time, which
is critical for compute use-cases.

Bug 200215465
Bug 1804898

Conflicts:
	drivers/gpu/nvgpu/gk20a/channel_gk20a.c

Change-Id: Ic4884ee4eac910b92b84a47fdc1b2e9f26b2f1f0
Signed-off-by: Bharat Nihalani <bnihalani@nvidia.com>
Reviewed-on: http://git-master/r/1199860
Reviewed-on: http://git-master/r/1209834
Reviewed-by: Automatic_Commit_Validation_User
GVS: Gerrit_Virtual_Submit
Reviewed-by: Deepak Nibade <dnibade@nvidia.com>
Reviewed-by: Terje Bergstrom <tbergstrom@nvidia.com>

4 files changed, 17 insertions, 17 deletions

diff --git a/drivers/gpu/nvgpu/gk20a/cde_gk20a.c b/drivers/gpu/nvgpu/gk20a/cde_gk20a.c
index f5b68e72..6f8c160c 100644
--- a/drivers/gpu/nvgpu/gk20a/cde_gk20a.c
+++ b/drivers/gpu/nvgpu/gk20a/cde_gk20a.c
@@ -1125,9 +1125,9 @@ __releases(&cde_app->mutex)
         struct gk20a_cde_app *cde_app = &g->cde_app;
         bool channel_idle;
 
-        mutex_lock(&ch->jobs_lock);
+        spin_lock(&ch->jobs_lock);
         channel_idle = list_empty(&ch->jobs);
-        mutex_unlock(&ch->jobs_lock);
+        spin_unlock(&ch->jobs_lock);
 
         if (!channel_idle)
                 return;
diff --git a/drivers/gpu/nvgpu/gk20a/ce2_gk20a.c b/drivers/gpu/nvgpu/gk20a/ce2_gk20a.c
index 8ea0b2d5..9be37a5e 100644
--- a/drivers/gpu/nvgpu/gk20a/ce2_gk20a.c
+++ b/drivers/gpu/nvgpu/gk20a/ce2_gk20a.c
@@ -126,9 +126,9 @@ static void gk20a_ce_finished_ctx_cb(struct channel_gk20a *ch, void *data)
         bool channel_idle;
         u32 event;
 
-        mutex_lock(&ch->jobs_lock);
+        spin_lock(&ch->jobs_lock);
         channel_idle = list_empty(&ch->jobs);
-        mutex_unlock(&ch->jobs_lock);
+        spin_unlock(&ch->jobs_lock);
 
         if (!channel_idle)
                 return;
diff --git a/drivers/gpu/nvgpu/gk20a/channel_gk20a.c b/drivers/gpu/nvgpu/gk20a/channel_gk20a.c
index d4cf6915..e45f7501 100644
--- a/drivers/gpu/nvgpu/gk20a/channel_gk20a.c
+++ b/drivers/gpu/nvgpu/gk20a/channel_gk20a.c
@@ -472,14 +472,14 @@ void gk20a_channel_abort_clean_up(struct channel_gk20a *ch)
 
         /* release all job semaphores (applies only to jobs that use
            semaphore synchronization) */
-        mutex_lock(&ch->jobs_lock);
+        spin_lock(&ch->jobs_lock);
         list_for_each_entry_safe(job, n, &ch->jobs, list) {
                 if (job->post_fence->semaphore) {
                         gk20a_semaphore_release(job->post_fence->semaphore);
                         released_job_semaphore = true;
                 }
         }
-        mutex_unlock(&ch->jobs_lock);
+        spin_unlock(&ch->jobs_lock);
 
         if (released_job_semaphore)
                 wake_up_interruptible_all(&ch->semaphore_wq);
@@ -512,9 +512,9 @@ int gk20a_wait_channel_idle(struct channel_gk20a *ch)
                 msecs_to_jiffies(gk20a_get_gr_idle_timeout(ch->g));
 
         do {
-                mutex_lock(&ch->jobs_lock);
+                spin_lock(&ch->jobs_lock);
                 channel_idle = list_empty(&ch->jobs);
-                mutex_unlock(&ch->jobs_lock);
+                spin_unlock(&ch->jobs_lock);
                 if (channel_idle)
                         break;
 
@@ -1850,9 +1850,9 @@ static int gk20a_channel_add_job(struct channel_gk20a *c,
 
                 gk20a_channel_timeout_start(c, job);
 
-                mutex_lock(&c->jobs_lock);
+                spin_lock(&c->jobs_lock);
                 list_add_tail(&job->list, &c->jobs);
-                mutex_unlock(&c->jobs_lock);
+                spin_unlock(&c->jobs_lock);
         } else {
                 err = -ETIMEDOUT;
                 goto err_free_job;
@@ -1898,14 +1898,14 @@ static void gk20a_channel_clean_up_jobs(struct work_struct *work)
         while (1) {
                 bool completed;
 
-                mutex_lock(&c->jobs_lock);
+                spin_lock(&c->jobs_lock);
                 if (list_empty(&c->jobs)) {
-                        mutex_unlock(&c->jobs_lock);
+                        spin_unlock(&c->jobs_lock);
                         break;
                 }
                 job = list_first_entry(&c->jobs,
                                        struct channel_gk20a_job, list);
-                mutex_unlock(&c->jobs_lock);
+                spin_unlock(&c->jobs_lock);
 
                 completed = gk20a_fence_is_expired(job->post_fence);
                 if (!completed) {
@@ -1948,9 +1948,9 @@ static void gk20a_channel_clean_up_jobs(struct work_struct *work)
                  * so this wouldn't get freed here. */
                 gk20a_channel_put(c);
 
-                mutex_lock(&c->jobs_lock);
+                spin_lock(&c->jobs_lock);
                 list_del_init(&job->list);
-                mutex_unlock(&c->jobs_lock);
+                spin_unlock(&c->jobs_lock);
 
                 kfree(job);
                 job_finished = 1;
@@ -2331,7 +2331,7 @@ int gk20a_init_channel_support(struct gk20a *g, u32 chid)
         c->referenceable = false;
         init_waitqueue_head(&c->ref_count_dec_wq);
         mutex_init(&c->ioctl_lock);
-        mutex_init(&c->jobs_lock);
+        spin_lock_init(&c->jobs_lock);
         mutex_init(&c->last_submit.fence_lock);
         mutex_init(&c->timeout.lock);
         mutex_init(&c->sync_lock);
diff --git a/drivers/gpu/nvgpu/gk20a/channel_gk20a.h b/drivers/gpu/nvgpu/gk20a/channel_gk20a.h
index 6469603b..4b2019dd 100644
--- a/drivers/gpu/nvgpu/gk20a/channel_gk20a.h
+++ b/drivers/gpu/nvgpu/gk20a/channel_gk20a.h
@@ -124,7 +124,7 @@ struct channel_gk20a {
         struct list_head ch_entry; /* channel's entry in TSG */
 
         struct list_head jobs;
-        struct mutex jobs_lock;
+        spinlock_t jobs_lock;
 
         struct vm_gk20a *vm;