diff options
| author | Chris Wilson <chris@chris-wilson.co.uk> | 2016-07-26 12:01:50 +0100 |
|---|---|---|
| committer | Chris Wilson <chris@chris-wilson.co.uk> | 2016-07-26 13:00:58 +0100 |
| commit | 4a50d20e105a4a8e46a641e4779e9431e0aabc84 (patch) | |
| tree | 7c8dae4a719186f150e2e6721cb4b8ba9de9b0f3 | |
| parent | d2b9448f96b566d19f4759afc0364c9d23634390 (diff) | |
drm/i915: Reduce breadcrumb lock coverage for intel_engine_enable_signaling()
Since intel_engine_enable_signaling() is now only called via
fence_enable_sw_signaling(), we can rely on it to provide serialisation
and run-once for us and so make ourselves slightly simpler.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/1469432687-22756-2-git-send-email-chris@chris-wilson.co.uk
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1469530913-17180-1-git-send-email-chris@chris-wilson.co.uk
| -rw-r--r-- | drivers/gpu/drm/i915/intel_breadcrumbs.c | 13 |
1 files changed, 4 insertions, 9 deletions
diff --git a/drivers/gpu/drm/i915/intel_breadcrumbs.c b/drivers/gpu/drm/i915/intel_breadcrumbs.c index d893ccdd62ac..90867446f1a5 100644 --- a/drivers/gpu/drm/i915/intel_breadcrumbs.c +++ b/drivers/gpu/drm/i915/intel_breadcrumbs.c @@ -480,19 +480,15 @@ void intel_engine_enable_signaling(struct drm_i915_gem_request *request) struct rb_node *parent, **p; bool first, wakeup; - if (unlikely(READ_ONCE(request->signaling.wait.tsk))) - return; - - spin_lock(&b->lock); - if (unlikely(request->signaling.wait.tsk)) { - wakeup = false; - goto unlock; - } + /* locked by fence_enable_sw_signaling() */ + assert_spin_locked(&request->lock); request->signaling.wait.tsk = b->signaler; request->signaling.wait.seqno = request->fence.seqno; i915_gem_request_get(request); + spin_lock(&b->lock); + /* First add ourselves into the list of waiters, but register our * bottom-half as the signaller thread. As per usual, only the oldest * waiter (not just signaller) is tasked as the bottom-half waking @@ -525,7 +521,6 @@ void intel_engine_enable_signaling(struct drm_i915_gem_request *request) if (first) smp_store_mb(b->first_signal, request); -unlock: spin_unlock(&b->lock); if (wakeup) |