On 09.12.21 11:23, Christian König wrote:
Always waiting for the exclusive fence resulted on some performance regressions. So try to wait for the shared fences first, then the exclusive fence should always be signaled already.
v2: fix incorrectly placed "(", add some comment why we do this.
Signed-off-by: Christian König christian.koenig@amd.com
Tested-by: Stefan Fritsch sf@sfritsch.de
Please also add a cc for linux-stable, so that this is fixed in 5.15.x
Cheers, Stefan
drivers/gpu/drm/nouveau/nouveau_fence.c | 28 +++++++++++++------------ 1 file changed, 15 insertions(+), 13 deletions(-)
diff --git a/drivers/gpu/drm/nouveau/nouveau_fence.c b/drivers/gpu/drm/nouveau/nouveau_fence.c index 05d0b3eb3690..0ae416aa76dc 100644 --- a/drivers/gpu/drm/nouveau/nouveau_fence.c +++ b/drivers/gpu/drm/nouveau/nouveau_fence.c @@ -353,15 +353,22 @@ nouveau_fence_sync(struct nouveau_bo *nvbo, struct nouveau_channel *chan, bool e
if (ret) return ret;
}
fobj = dma_resv_shared_list(resv);
fence = dma_resv_excl_fence(resv);
fobj = NULL;- } else {
fobj = dma_resv_shared_list(resv);- }
- if (fence) {
/* Waiting for the exclusive fence first causes performance regressions
* under some circumstances. So manually wait for the shared ones first.*/for (i = 0; i < (fobj ? fobj->shared_count : 0) && !ret; ++i) { struct nouveau_channel *prev = NULL; bool must_wait = true;
fence = rcu_dereference_protected(fobj->shared[i],dma_resv_held(resv));f = nouveau_local_fence(fence, chan->drm); if (f) { rcu_read_lock();
@@ -373,20 +380,13 @@ nouveau_fence_sync(struct nouveau_bo *nvbo, struct nouveau_channel *chan, bool e
if (must_wait) ret = dma_fence_wait(fence, intr);
return ret;}
if (!exclusive || !fobj)
return ret;for (i = 0; i < fobj->shared_count && !ret; ++i) {
- fence = dma_resv_excl_fence(resv);
- if (fence) { struct nouveau_channel *prev = NULL; bool must_wait = true;
fence = rcu_dereference_protected(fobj->shared[i],dma_resv_held(resv));- f = nouveau_local_fence(fence, chan->drm); if (f) { rcu_read_lock();
@@ -398,6 +398,8 @@ nouveau_fence_sync(struct nouveau_bo *nvbo, struct nouveau_channel *chan, bool e
if (must_wait) ret = dma_fence_wait(fence, intr);
return ret;}
return ret;