drm/i915: Make i915_gem_context_mark_guilty() safe for unlocked updates
Since we make call i915_gem_context_mark_guilty() concurrently when
resetting different engines in parallel, we need to make sure that our
updates are safe for the unlocked access.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Michel Thierry <michel.thierry@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170721123238.16428-12-chris@chris-wilson.co.uk
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/i915_gem_request.c b/drivers/gpu/drm/i915/i915_gem_request.c
index d93a185..68e406a 100644
--- a/drivers/gpu/drm/i915/i915_gem_request.c
+++ b/drivers/gpu/drm/i915/i915_gem_request.c
@@ -374,8 +374,7 @@ static void i915_gem_request_retire(struct drm_i915_gem_request *request)
i915_gem_request_remove_from_client(request);
/* Retirement decays the ban score as it is a sign of ctx progress */
- if (request->ctx->ban_score > 0)
- request->ctx->ban_score--;
+ atomic_dec_if_positive(&request->ctx->ban_score);
/* The backing object for the context is done after switching to the
* *next* context. Therefore we cannot retire the previous context until