gpu: nvgpu: implement sync refcounting

We currently free sync when we find job list empty
If aggressive_sync is set to true, we try to free
sync during channel unbind() call

But we rarely free sync from channel_unbind() call
since freeing it when job list is empty is
aggressive enough

Hence remove sync free code from channel_unbind()

Implement refcounting for sync:
- get a refcount while submitting a job (and
  allocate sync if it is not allocated already)
- put a refcount while freeing the job
- if refcount==0 and if aggressive_sync_destroy is
  set, free the sync
- if aggressive_sync_destroy is not set, we will
  free the sync during channel close time

Bug 200187553

Change-Id: I74e24adb15dc26a375ebca1fdd017b3ad6d57b61
Signed-off-by: Deepak Nibade <dnibade@nvidia.com>
Reviewed-on: http://git-master/r/1120410
Reviewed-by: Terje Bergstrom <tbergstrom@nvidia.com>
Tested-by: Terje Bergstrom <tbergstrom@nvidia.com>

1 files changed, 0 insertions, 10 deletions

diff --git a/drivers/gpu/nvgpu/vgpu/fifo_vgpu.c b/drivers/gpu/nvgpu/vgpu/fifo_vgpu.c
index 535de851..294581b9 100644
--- a/drivers/gpu/nvgpu/vgpu/fifo_vgpu.c
+++ b/drivers/gpu/nvgpu/vgpu/fifo_vgpu.c
@@ -59,16 +59,6 @@ static void vgpu_channel_unbind(struct channel_gk20a *ch)
         }
 
         ch->bound = false;
-
-        /*
-         * if we are agrressive then we can destroy the syncpt
-         * resource at this point
-         * if not, then it will be destroyed at channel_free()
-         */
-        if (ch->sync && platform->aggressive_sync_destroy) {
-                ch->sync->destroy(ch->sync);
-                ch->sync = NULL;
-        }
 }
 
 static int vgpu_channel_alloc_inst(struct gk20a *g, struct channel_gk20a *ch)