From: Chris Wilson Date: Thu, 18 May 2017 09:46:18 +0000 (+0100) Subject: drm/i915: Reinstate reservation_object zapping for batch_pool objects X-Git-Tag: v4.13-rc1~45^2~13^2~45 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=9ee82d783eef3177928a586c1df3f08d9ced72a8;p=platform%2Fkernel%2Flinux-exynos.git drm/i915: Reinstate reservation_object zapping for batch_pool objects I removed the zapping of the reservation_object->fence array of shared fences prematurely. We don't yet have the code to zap that array when retiring the object, and so currently it remains possible to continually grow the shared array trapping requests when reusing the batch_pool object across many timelines. Signed-off-by: Chris Wilson Cc: Tvrtko Ursulin Cc: Joonas Lahtinen Cc: Mika Kuoppala Cc: Matthew Auld Reviewed-by: Tvrtko Ursulin Link: http://patchwork.freedesktop.org/patch/msgid/20170518094638.5469-4-chris@chris-wilson.co.uk --- diff --git a/drivers/gpu/drm/i915/i915_gem_batch_pool.c b/drivers/gpu/drm/i915/i915_gem_batch_pool.c index 41aa598..c93005c 100644 --- a/drivers/gpu/drm/i915/i915_gem_batch_pool.c +++ b/drivers/gpu/drm/i915/i915_gem_batch_pool.c @@ -114,12 +114,27 @@ i915_gem_batch_pool_get(struct i915_gem_batch_pool *pool, list_for_each_entry(obj, list, batch_pool_link) { /* The batches are strictly LRU ordered */ if (i915_gem_object_is_active(obj)) { - if (!reservation_object_test_signaled_rcu(obj->resv, - true)) + struct reservation_object *resv = obj->resv; + + if (!reservation_object_test_signaled_rcu(resv, true)) break; i915_gem_retire_requests(pool->engine->i915); GEM_BUG_ON(i915_gem_object_is_active(obj)); + + /* + * The object is now idle, clear the array of shared + * fences before we add a new request. Although, we + * remain on the same engine, we may be on a different + * timeline and so may continually grow the array, + * trapping a reference to all the old fences, rather + * than replace the existing fence. + */ + if (rcu_access_pointer(resv->fence)) { + reservation_object_lock(resv, NULL); + reservation_object_add_excl_fence(resv, NULL); + reservation_object_unlock(resv); + } } GEM_BUG_ON(!reservation_object_test_signaled_rcu(obj->resv,