[PATCH V2] dma-buf: Fix missing excl fence waiting

From: Pan, Xinhui
Date: Sun Feb 23 2020 - 07:04:18 EST


If shared fence list is not empty, even we want to test all fences, excl fence is ignored.
That is abviously wrong, so fix it.

Signed-off-by: xinhui pan <xinhui.pan@xxxxxxx>
---
change from v1:
init left correctly
---
drivers/dma-buf/dma-resv.c | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/drivers/dma-buf/dma-resv.c b/drivers/dma-buf/dma-resv.c
index 4264e64788c4..82e4b4f63bef 100644
--- a/drivers/dma-buf/dma-resv.c
+++ b/drivers/dma-buf/dma-resv.c
@@ -632,13 +632,13 @@ static inline int dma_resv_test_signaled_single(struct dma_fence *passed_fence)
*/
bool dma_resv_test_signaled_rcu(struct dma_resv *obj, bool test_all)
{
- unsigned seq, shared_count;
+ unsigned int seq, shared_count, left;
int ret;

rcu_read_lock();
retry:
ret = true;
- shared_count = 0;
+ left = shared_count = 0;
seq = read_seqcount_begin(&obj->seq);

if (test_all) {
@@ -647,7 +647,7 @@ bool dma_resv_test_signaled_rcu(struct dma_resv *obj, bool test_all)
struct dma_resv_list *fobj = rcu_dereference(obj->fence);

if (fobj)
- shared_count = fobj->shared_count;
+ left = shared_count = fobj->shared_count;

for (i = 0; i < shared_count; ++i) {
struct dma_fence *fence = rcu_dereference(fobj->shared[i]);
@@ -657,13 +657,14 @@ bool dma_resv_test_signaled_rcu(struct dma_resv *obj, bool test_all)
goto retry;
else if (!ret)
break;
+ left--;
}

if (read_seqcount_retry(&obj->seq, seq))
goto retry;
}

- if (!shared_count) {
+ if (!left) {
struct dma_fence *fence_excl = rcu_dereference(obj->fence_excl);

if (fence_excl) {
--
2.21.0 (Apple Git-122)