dma-fence: Propagate errors to dma-fence-array container

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.
v4: Same applies to installing the signal cb.
v5: Use cmpxchg to only set the error once before using a nifty idea by
Christian to avoid changing the status after emitting the signal.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: Gustavo Padovan <gustavo@padovan.org>
Cc: Christian König <christian.koenig@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190811210902.22112-1-chris@chris-wilson.co.uk
This commit is contained in:
Chris Wilson 2019-08-11 22:09:02 +01:00
parent e0d409ff16
commit 1f70b8b812

View File

@ -13,6 +13,8 @@
#include <linux/slab.h>
#include <linux/dma-fence-array.h>
#define PENDING_ERROR 1
static const char *dma_fence_array_get_driver_name(struct dma_fence *fence)
{
return "dma_fence_array";
@ -23,10 +25,29 @@ static const char *dma_fence_array_get_timeline_name(struct dma_fence *fence)
return "unbound";
}
static void dma_fence_array_set_pending_error(struct dma_fence_array *array,
int error)
{
/*
* Propagate the first error reported by any of our fences, but only
* before we ourselves are signaled.
*/
if (error)
cmpxchg(&array->base.error, PENDING_ERROR, error);
}
static void dma_fence_array_clear_pending_error(struct dma_fence_array *array)
{
/* Clear the error flag if not actually set. */
cmpxchg(&array->base.error, PENDING_ERROR, 0);
}
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_clear_pending_error(array);
dma_fence_signal(&array->base);
dma_fence_put(&array->base);
}
@ -38,6 +59,8 @@ 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;
dma_fence_array_set_pending_error(array, f->error);
if (atomic_dec_and_test(&array->num_pending))
irq_work_queue(&array->work);
else
@ -63,9 +86,14 @@ 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)) {
int error = array->fences[i]->error;
dma_fence_array_set_pending_error(array, error);
dma_fence_put(&array->base);
if (atomic_dec_and_test(&array->num_pending))
if (atomic_dec_and_test(&array->num_pending)) {
dma_fence_array_clear_pending_error(array);
return false;
}
}
}
@ -142,6 +170,8 @@ struct dma_fence_array *dma_fence_array_create(int num_fences,
atomic_set(&array->num_pending, signal_on_any ? 1 : num_fences);
array->fences = fences;
array->base.error = PENDING_ERROR;
return array;
}
EXPORT_SYMBOL(dma_fence_array_create);