From 4c2488cfaa997e396aeb9d6496db94c25b97c671 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Christian=20K=C3=B6nig?= Date: Mon, 5 Aug 2019 13:18:43 +0200 Subject: [PATCH] drm/i915: stop using seqcount for fence pruning MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit After waiting for a reservation object use reservation_object_test_signaled_rcu to opportunistically prune the fences on the object. This allows removal of the seqcount handling in the reservation object. Signed-off-by: Christian König Reviewed-by: Chris Wilson Link: https://patchwork.freedesktop.org/patch/322032/?series=64786&rev=1 --- drivers/gpu/drm/i915/gem/i915_gem_wait.c | 14 +++++--------- 1 file changed, 5 insertions(+), 9 deletions(-) diff --git a/drivers/gpu/drm/i915/gem/i915_gem_wait.c b/drivers/gpu/drm/i915/gem/i915_gem_wait.c index 26ec6579b7cd..fa46a54bcbe7 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_wait.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_wait.c @@ -35,7 +35,6 @@ i915_gem_object_wait_reservation(struct reservation_object *resv, unsigned int flags, long timeout) { - unsigned int seq = __read_seqcount_begin(&resv->seq); struct dma_fence *excl; bool prune_fences = false; @@ -83,15 +82,12 @@ i915_gem_object_wait_reservation(struct reservation_object *resv, /* * Opportunistically prune the fences iff we know they have *all* been - * signaled and that the reservation object has not been changed (i.e. - * no new fences have been added). + * signaled. */ - if (prune_fences && !__read_seqcount_retry(&resv->seq, seq)) { - if (reservation_object_trylock(resv)) { - if (!__read_seqcount_retry(&resv->seq, seq)) - reservation_object_add_excl_fence(resv, NULL); - reservation_object_unlock(resv); - } + if (prune_fences && reservation_object_trylock(resv)) { + if (reservation_object_test_signaled_rcu(resv, true)) + reservation_object_add_excl_fence(resv, NULL); + reservation_object_unlock(resv); } return timeout; -- 2.30.2