When one of the array of fences is signaled, propagate its errors to the parent fence-array (keeping the first error to be raised).
v2: Opencode cmpxchg_local to avoid compiler freakout. v3: Be careful not to flag an error if we race against signal-on-any Signed-off-by: Chris Wilson <ch...@chris-wilson.co.uk> Cc: Sumit Semwal <sumit.sem...@linaro.org> Cc: Gustavo Padovan <gust...@padovan.org> Cc: Christian König <christian.koe...@amd.com> --- drivers/dma-buf/dma-fence-array.c | 25 +++++++++++++++++++++++++ include/linux/dma-fence-array.h | 2 ++ 2 files changed, 27 insertions(+) diff --git a/drivers/dma-buf/dma-fence-array.c b/drivers/dma-buf/dma-fence-array.c index 12c6f64c0bc2..e806c5fe9ec9 100644 --- a/drivers/dma-buf/dma-fence-array.c +++ b/drivers/dma-buf/dma-fence-array.c @@ -23,10 +23,19 @@ static const char *dma_fence_array_get_timeline_name(struct dma_fence *fence) return "unbound"; } +static void dma_fence_array_set_error_once(struct dma_fence_array *array, + int error) +{ + if (!array->base.error && error) + dma_fence_set_error(&array->base, error); +} + static void irq_dma_fence_array_work(struct irq_work *wrk) { struct dma_fence_array *array = container_of(wrk, typeof(*array), work); + dma_fence_array_set_error_once(array, READ_ONCE(array->pending_error)); + dma_fence_signal(&array->base); dma_fence_put(&array->base); } @@ -38,6 +47,19 @@ static void dma_fence_array_cb_func(struct dma_fence *f, container_of(cb, struct dma_fence_array_cb, cb); struct dma_fence_array *array = array_cb->array; + /* + * Propagate the first error reported by any of our fences, but only + * before we ourselves are signaled. + * + * Note that this may race with multiple fences completing + * simultaneously in error, but only one error will be kept, not + * necessarily the first. So long as we propagate an error if any + * fences were in error before we are signaled we should be telling + * an acceptable truth. + */ + if (f->error && !array->pending_error) + WRITE_ONCE(array->pending_error, f->error); + if (atomic_dec_and_test(&array->num_pending)) irq_work_queue(&array->work); else @@ -63,6 +85,8 @@ static bool dma_fence_array_enable_signaling(struct dma_fence *fence) dma_fence_get(&array->base); if (dma_fence_add_callback(array->fences[i], &cb[i].cb, dma_fence_array_cb_func)) { + dma_fence_array_set_error_once(array, + array->fences[i]->error); dma_fence_put(&array->base); if (atomic_dec_and_test(&array->num_pending)) return false; @@ -141,6 +165,7 @@ struct dma_fence_array *dma_fence_array_create(int num_fences, array->num_fences = num_fences; atomic_set(&array->num_pending, signal_on_any ? 1 : num_fences); array->fences = fences; + array->pending_error = 0; return array; } diff --git a/include/linux/dma-fence-array.h b/include/linux/dma-fence-array.h index 303dd712220f..faaf70c524ae 100644 --- a/include/linux/dma-fence-array.h +++ b/include/linux/dma-fence-array.h @@ -42,6 +42,8 @@ struct dma_fence_array { atomic_t num_pending; struct dma_fence **fences; + int pending_error; + struct irq_work work; }; -- 2.23.0.rc1 _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel