On 20/09/2021 09:45, Tvrtko Ursulin wrote:
On 17/09/2021 13:35, Christian König wrote:
Simplifying the code a bit.
v2: use dma_resv_for_each_fence instead, according to Tvrtko the lock is
held here anyway.
v3: back to using dma_resv_for_each_fence_unlocked.
It did not work out - what happened?
Wait, my suggestion to try the locked iterator was against
i915_request_await_object. I haven't looked at this one at the time or
even now.
Regards,
Tvrtko
Regards,
Tvrtko
Signed-off-by: Christian König <christian.koenig@xxxxxxx>
---
drivers/gpu/drm/i915/i915_sw_fence.c | 57 ++++++++--------------------
1 file changed, 15 insertions(+), 42 deletions(-)
diff --git a/drivers/gpu/drm/i915/i915_sw_fence.c
b/drivers/gpu/drm/i915/i915_sw_fence.c
index c589a681da77..7635b0478ea5 100644
--- a/drivers/gpu/drm/i915/i915_sw_fence.c
+++ b/drivers/gpu/drm/i915/i915_sw_fence.c
@@ -572,56 +572,29 @@ int i915_sw_fence_await_reservation(struct
i915_sw_fence *fence,
unsigned long timeout,
gfp_t gfp)
{
- struct dma_fence *excl;
+ struct dma_resv_iter cursor;
+ struct dma_fence *f;
int ret = 0, pending;
debug_fence_assert(fence);
might_sleep_if(gfpflags_allow_blocking(gfp));
- if (write) {
- struct dma_fence **shared;
- unsigned int count, i;
-
- ret = dma_resv_get_fences(resv, &excl, &count, &shared);
- if (ret)
- return ret;
-
- for (i = 0; i < count; i++) {
- if (shared[i]->ops == exclude)
- continue;
-
- pending = i915_sw_fence_await_dma_fence(fence,
- shared[i],
- timeout,
- gfp);
- if (pending < 0) {
- ret = pending;
- break;
- }
-
- ret |= pending;
- }
-
- for (i = 0; i < count; i++)
- dma_fence_put(shared[i]);
- kfree(shared);
- } else {
- excl = dma_resv_get_excl_unlocked(resv);
- }
-
- if (ret >= 0 && excl && excl->ops != exclude) {
- pending = i915_sw_fence_await_dma_fence(fence,
- excl,
- timeout,
+ rcu_read_lock();
+ dma_resv_iter_begin(&cursor, resv, write);
+ dma_resv_for_each_fence_unlocked(&cursor, f) {
+ rcu_read_unlock();
+ pending = i915_sw_fence_await_dma_fence(fence, f, timeout,
gfp);
- if (pending < 0)
+ rcu_read_lock();
+ if (pending < 0) {
ret = pending;
- else
- ret |= pending;
- }
-
- dma_fence_put(excl);
+ break;
+ }
+ ret |= pending;
+ }
+ dma_resv_iter_end(&cursor);
+ rcu_read_unlock();
return ret;
}
