-----Original Message----- From: Christian König [mailto:deathsimple@vodafone.de] Sent: Monday, July 31, 2017 10:13 AM To: linux-media@vger.kernel.org; dri-devel@lists.freedesktop.org; linaro- mm-sig@lists.linaro.org; Zhou, David(ChunMing); Deucher, Alexander Subject: Re: [PATCH] dma-buf: fix reservation_object_wait_timeout_rcu to wait correctly v2
Ping, what do you guys think of that?
Seems reasonable to me. Reviewed-by: Alex Deucher alexander.deucher@amd.com
Am 25.07.2017 um 15:35 schrieb Christian König:
From: Christian König christian.koenig@amd.com
With hardware resets in mind it is possible that all shared fences are signaled, but the exlusive isn't. Fix waiting for everything in this situation.
v2: make sure we always wait for the exclusive fence
Signed-off-by: Christian König christian.koenig@amd.com
drivers/dma-buf/reservation.c | 33 +++++++++++++++------------------ 1 file changed, 15 insertions(+), 18 deletions(-)
diff --git a/drivers/dma-buf/reservation.c b/drivers/dma-buf/reservation.c index 393817e..9d4316d 100644 --- a/drivers/dma-buf/reservation.c +++ b/drivers/dma-buf/reservation.c @@ -373,12 +373,25 @@ long reservation_object_wait_timeout_rcu(struct
reservation_object *obj,
long ret = timeout ? timeout : 1;
retry:
fence = NULL; shared_count = 0; seq = read_seqcount_begin(&obj->seq); rcu_read_lock();
if (wait_all) {
- fence = rcu_dereference(obj->fence_excl);
- if (fence && !test_bit(DMA_FENCE_FLAG_SIGNALED_BIT, &fence-
flags)) {
if (!dma_fence_get_rcu(fence))goto unlock_retry;if (dma_fence_is_signaled(fence)) {dma_fence_put(fence);fence = NULL;}- } else {
fence = NULL;- }
- if (!fence && wait_all) { struct reservation_object_list *fobj = rcu_dereference(obj-
fence);
@@ -405,22 +418,6 @@ long reservation_object_wait_timeout_rcu(struct
reservation_object *obj,
}}
- if (!shared_count) {
struct dma_fence *fence_excl = rcu_dereference(obj-fence_excl);
if (fence_excl &&!test_bit(DMA_FENCE_FLAG_SIGNALED_BIT,&fence_excl->flags)) {if (!dma_fence_get_rcu(fence_excl))goto unlock_retry;if (dma_fence_is_signaled(fence_excl))dma_fence_put(fence_excl);elsefence = fence_excl;}- }
- rcu_read_unlock(); if (fence) { if (read_seqcount_retry(&obj->seq, seq)) {