gpu: nvgpu: cde: allow duplicate finish signals

Channel update callback for a channel that has no more cde jobs signals
that a cde context is free. Spurious channel updates may still happen
from at least nonstalling semaphore wait interrupts. Instead of scary
WARNs, use only gk20a_dbg_info() for info prints in these harmless
situations, and double check that only the first update starts a deleter
work for temporary contexts.

Change-Id: I68de8f35e2c366206c6efac3ee97025239e8bba2
Signed-off-by: Konsta Holtta <kholtta@nvidia.com>
(cherry-picked from commit f56a941b4962c5479291cae48e2abca6067e3f13)
Reviewed-on: http://git-master/r/660849
Reviewed-by: Terje Bergstrom <tbergstrom@nvidia.com>
Tested-by: Terje Bergstrom <tbergstrom@nvidia.com>

1 files changed, 7 insertions, 5 deletions

diff --git a/drivers/gpu/nvgpu/gk20a/cde_gk20a.c b/drivers/gpu/nvgpu/gk20a/cde_gk20a.c
index d2384257..f3185dd9 100644
--- a/drivers/gpu/nvgpu/gk20a/cde_gk20a.c
+++ b/drivers/gpu/nvgpu/gk20a/cde_gk20a.c
@@ -759,7 +759,8 @@ __releases(&cde_app->mutex)
 
         mutex_lock(&cde_app->mutex);
 
-        WARN(!cde_ctx->in_use, "double release cde context %p", cde_ctx);
+        if (!cde_ctx->in_use)
+                gk20a_dbg_info("double release cde context %p", cde_ctx);
 
         cde_ctx->in_use = false;
         list_move(&cde_ctx->list, &cde_app->free_contexts);
@@ -1073,8 +1074,9 @@ __releases(&cde_app->mutex)
 
         trace_gk20a_cde_finished_ctx_cb(cde_ctx);
         gk20a_dbg(gpu_dbg_fn | gpu_dbg_cde_ctx, "cde: finished %p", cde_ctx);
-        WARN(!cde_ctx->in_use, "double finish cde context %p on channel %p",
-                        cde_ctx, ch);
+        if (!cde_ctx->in_use)
+                gk20a_dbg_info("double finish cde context %p on channel %p",
+                                cde_ctx, ch);
 
         if (ch->has_timedout) {
                 if (cde_ctx->is_temporary) {
@@ -1097,8 +1099,8 @@ __releases(&cde_app->mutex)
                 }
         }
 
-        /* delete temporary contexts later */
-        if (cde_ctx->is_temporary) {
+        /* delete temporary contexts later (watch for doubles) */
+        if (cde_ctx->is_temporary && cde_ctx->in_use) {
                 WARN_ON(delayed_work_pending(&cde_ctx->ctx_deleter_work));
                 schedule_delayed_work(&cde_ctx->ctx_deleter_work,
                         msecs_to_jiffies(CTX_DELETE_TIME));