Re: [Intel-gfx] [PATCH 02/28] drm/i915: use new iterator in i915_gem_object_wait_reservation

Christian König
2021-10-21T10:39:10Z

Am 21.10.21 um 12:35 schrieb Maarten Lankhorst:
> From: Christian König <christian.koenig@amd.com>
>
> Simplifying the code a bit.
>
> Signed-off-by: Christian König <christian.koenig@amd.com>
> [mlankhorst: Handle timeout = 0 correctly, use new i915_request_wait_timeout.]
> Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>

LGTM, do you want to push it or should I pick it up into drm-misc-next?

Christian.

> ---
> drivers/gpu/drm/i915/gem/i915_gem_wait.c | 65 ++++++++----------------
> 1 file changed, 20 insertions(+), 45 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/gem/i915_gem_wait.c b/drivers/gpu/drm/i915/gem/i915_gem_wait.c
> index f909aaa09d9c..840c13706999 100644
> --- a/drivers/gpu/drm/i915/gem/i915_gem_wait.c
> +++ b/drivers/gpu/drm/i915/gem/i915_gem_wait.c
> @@ -25,7 +25,7 @@ i915_gem_object_wait_fence(struct dma_fence *fence,
> return timeout;
>
> if (dma_fence_is_i915(fence))
> - return i915_request_wait(to_request(fence), flags, timeout);
> + return i915_request_wait_timeout(to_request(fence), flags, timeout);
>
> return dma_fence_wait_timeout(fence,
> flags & I915_WAIT_INTERRUPTIBLE,
> @@ -37,58 +37,29 @@ i915_gem_object_wait_reservation(struct dma_resv *resv,
> unsigned int flags,
> long timeout)
> {
> - struct dma_fence *excl;
> - bool prune_fences = false;
> -
> - if (flags & I915_WAIT_ALL) {
> - struct dma_fence **shared;
> - unsigned int count, i;
> - int ret;
> -
> - ret = dma_resv_get_fences(resv, &excl, &count, &shared);
> - if (ret)
> - return ret;
> -
> - for (i = 0; i < count; i++) {
> - timeout = i915_gem_object_wait_fence(shared[i],
> - flags, timeout);
> - if (timeout < 0)
> - break;
> -
> - dma_fence_put(shared[i]);
> - }
> -
> - for (; i < count; i++)
> - dma_fence_put(shared[i]);
> - kfree(shared);
> + struct dma_resv_iter cursor;
> + struct dma_fence *fence;
> + long ret = timeout ?: 1;
> +
> + dma_resv_iter_begin(&cursor, resv, flags & I915_WAIT_ALL);
> + dma_resv_for_each_fence_unlocked(&cursor, fence) {
> + ret = i915_gem_object_wait_fence(fence, flags, timeout);
> + if (ret <= 0)
> + break;
>
> - /*
> - * If both shared fences and an exclusive fence exist,
> - * then by construction the shared fences must be later
> - * than the exclusive fence. If we successfully wait for
> - * all the shared fences, we know that the exclusive fence
> - * must all be signaled. If all the shared fences are
> - * signaled, we can prune the array and recover the
> - * floating references on the fences/requests.
> - */
> - prune_fences = count && timeout >= 0;
> - } else {
> - excl = dma_resv_get_excl_unlocked(resv);
> + if (timeout)
> + timeout = ret;
> }
> -
> - if (excl && timeout >= 0)
> - timeout = i915_gem_object_wait_fence(excl, flags, timeout);
> -
> - dma_fence_put(excl);
> + dma_resv_iter_end(&cursor);
>
> /*
> * Opportunistically prune the fences iff we know they have *all* been
> * signaled.
> */
> - if (prune_fences)
> + if (timeout > 0)
> dma_resv_prune(resv);
>
> - return timeout;
> + return ret;
> }
>
> static void fence_set_priority(struct dma_fence *fence,
> @@ -196,7 +167,11 @@ i915_gem_object_wait(struct drm_i915_gem_object *obj,
>
> timeout = i915_gem_object_wait_reservation(obj->base.resv,
> flags, timeout);
> - return timeout < 0 ? timeout : 0;
> +
> + if (timeout < 0)
> + return timeout;
> +
> + return !timeout ? -ETIME : 0;
> }
>
> static inline unsigned long nsecs_to_jiffies_timeout(const u64 n)