gpu: nvgpu: Base channel watchdog on gp_get

Instead of checking if a job is complete, only check that channel is
making progress by checking its gp_get is advancing.

This will make the watchdog conservative. Previously a whole job had
x seconds to complete. Now channel has x seconds to get host to
consume each push buffer segment.

Bug 1861838
Bug 200273419
Bug 200263100

Change-Id: I70adc1f50301bce8db7dac675771c251c0f11b70
Signed-off-by: Terje Bergstrom <tbergstrom@nvidia.com>
Reviewed-on: http://git-master/r/1294850
Reviewed-by: Automatic_Commit_Validation_User

1 files changed, 9 insertions, 15 deletions

diff --git a/drivers/gpu/nvgpu/gk20a/channel_gk20a.c b/drivers/gpu/nvgpu/gk20a/channel_gk20a.c
index 1ee9b59a..e272b130 100644
--- a/drivers/gpu/nvgpu/gk20a/channel_gk20a.c
+++ b/drivers/gpu/nvgpu/gk20a/channel_gk20a.c
@@ -2078,8 +2078,7 @@ static void trace_write_pushbuffer_range(struct channel_gk20a *c,
                 nvgpu_kfree(g);
 }
 
-static void gk20a_channel_timeout_start(struct channel_gk20a *ch,
-                struct channel_gk20a_job *job)
+static void gk20a_channel_timeout_start(struct channel_gk20a *ch)
 {
         struct gk20a_platform *platform = gk20a_get_platform(ch->g->dev);
 
@@ -2096,7 +2095,7 @@ static void gk20a_channel_timeout_start(struct channel_gk20a *ch,
                 return;
         }
 
-        ch->timeout.job = job;
+        ch->timeout.gp_get = gk20a_userd_gp_get(ch->g, ch);
         ch->timeout.initialized = true;
         raw_spin_unlock(&ch->timeout.lock);
 
@@ -2150,7 +2149,7 @@ void gk20a_channel_timeout_restart_all_channels(struct gk20a *g)
 
 static void gk20a_channel_timeout_handler(struct work_struct *work)
 {
-        struct channel_gk20a_job *job;
+        u32 gp_get;
         struct gk20a *g;
         struct channel_gk20a *ch;
 
@@ -2170,23 +2169,18 @@ static void gk20a_channel_timeout_handler(struct work_struct *work)
         /* Need global lock since multiple channels can timeout at a time */
         mutex_lock(&g->ch_wdt_lock);
 
-        gk20a_err(dev_from_gk20a(g), "Possible job timeout on ch=%d",
-                  ch->hw_chid);
-
         /* Get timed out job and reset the timer */
         raw_spin_lock(&ch->timeout.lock);
-        job = ch->timeout.job;
+        gp_get = ch->timeout.gp_get;
         ch->timeout.initialized = false;
         raw_spin_unlock(&ch->timeout.lock);
 
-        if (gk20a_fence_is_expired(job->post_fence)) {
-                gk20a_err(dev_from_gk20a(g),
-                          "Timed out fence is expired on c=%d!",
-                          ch->hw_chid);
+        if (gk20a_userd_gp_get(ch->g, ch) != gp_get) {
+                gk20a_channel_timeout_start(ch);
                 goto fail_unlock;
         }
 
-        gk20a_err(dev_from_gk20a(g), "Confirmed: job on channel %d timed out",
+        gk20a_err(dev_from_gk20a(g), "Job on channel %d timed out",
                   ch->hw_chid);
 
         gk20a_debug_dump(g->dev);
@@ -2275,7 +2269,7 @@ static int gk20a_channel_add_job(struct channel_gk20a *c,
                 job->num_mapped_buffers = num_mapped_buffers;
                 job->mapped_buffers = mapped_buffers;
 
-                gk20a_channel_timeout_start(c, job);
+                gk20a_channel_timeout_start(c);
 
                 if (!pre_alloc_enabled)
                         channel_gk20a_joblist_lock(c);
@@ -2357,7 +2351,7 @@ static void gk20a_channel_clean_up_jobs(struct channel_gk20a *c,
 
                 completed = gk20a_fence_is_expired(job->post_fence);
                 if (!completed) {
-                        gk20a_channel_timeout_start(c, job);
+                        gk20a_channel_timeout_start(c);
                         break;
                 }