leandrof/linux
1
0
Fork 0
forked from Minki/linux
Code Issues Pull Requests Packages Projects Releases Wiki Activity

drm/i915: Fix i915_request fence wait semantics

Browse Source 
The i915_request fence wait behaves differently for timeout = 0
compared to expected dma-fence behavior.

i915 behavior:
- Unsignaled: -ETIME
- Signaled: 0 (= timeout)

Expected:
- Unsignaled: 0
- Signaled: 1

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Acked-by: Daniel Vetter <daniel@ffwll.ch>
Acked-by: Christian König <christian.koenig@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211116102431.198905-6-christian.koenig@amd.com
Signed-off-by: Christian König <christian.koenig@amd.com>
This commit is contained in:
Maarten Lankhorst 2021-10-21 12:35:38 +02:00 committed by Christian König
parent 5e9ddbdcf7
commit 7e2e69ed46
2 changed files with 52 additions and 10 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

57
drivers/gpu/drm/i915/i915_request.c
View File

@ -96,9 +96,9 @@ static signed long i915_fence_wait(struct dma_fence *fence,
bool interruptible,
signed long timeout)
{
return i915_request_wait(to_request(fence),
interruptible | I915_WAIT_PRIORITY,
timeout);
return i915_request_wait_timeout(to_request(fence),
interruptible | I915_WAIT_PRIORITY,
timeout);
}
struct kmem_cache *i915_request_slab_cache(void)
@ -1857,23 +1857,27 @@ static void request_wait_wake(struct dma_fence *fence, struct dma_fence_cb *cb)
}
/**
* i915_request_wait - wait until execution of request has finished
* i915_request_wait_timeout - wait until execution of request has finished
* @rq: the request to wait upon
* @flags: how to wait
* @timeout: how long to wait in jiffies
*
* i915_request_wait() waits for the request to be completed, for a
* i915_request_wait_timeout() waits for the request to be completed, for a
* maximum of @timeout jiffies (with MAX_SCHEDULE_TIMEOUT implying an
* unbounded wait).
*
* Returns the remaining time (in jiffies) if the request completed, which may
* be zero or -ETIME if the request is unfinished after the timeout expires.
* be zero if the request is unfinished after the timeout expires.
* If the timeout is 0, it will return 1 if the fence is signaled.
*
* May return -EINTR is called with I915_WAIT_INTERRUPTIBLE and a signal is
* pending before the request completes.
*
* NOTE: This function has the same wait semantics as dma-fence.
*/
long i915_request_wait(struct i915_request *rq,
unsigned int flags,
long timeout)
long i915_request_wait_timeout(struct i915_request *rq,
unsigned int flags,
long timeout)
{
const int state = flags & I915_WAIT_INTERRUPTIBLE ?
TASK_INTERRUPTIBLE : TASK_UNINTERRUPTIBLE;
@ -1883,7 +1887,7 @@ long i915_request_wait(struct i915_request *rq,
GEM_BUG_ON(timeout < 0);
if (dma_fence_is_signaled(&rq->fence))
return timeout;
return timeout ?: 1;
if (!timeout)
return -ETIME;
@ -1992,6 +1996,39 @@ out:
return timeout;
}
/**
* i915_request_wait - wait until execution of request has finished
* @rq: the request to wait upon
* @flags: how to wait
* @timeout: how long to wait in jiffies
*
* i915_request_wait() waits for the request to be completed, for a
* maximum of @timeout jiffies (with MAX_SCHEDULE_TIMEOUT implying an
* unbounded wait).
*
* Returns the remaining time (in jiffies) if the request completed, which may
* be zero or -ETIME if the request is unfinished after the timeout expires.
* May return -EINTR is called with I915_WAIT_INTERRUPTIBLE and a signal is
* pending before the request completes.
*
* NOTE: This function behaves differently from dma-fence wait semantics for
* timeout = 0. It returns 0 on success, and -ETIME if not signaled.
*/
long i915_request_wait(struct i915_request *rq,
unsigned int flags,
long timeout)
{
long ret = i915_request_wait_timeout(rq, flags, timeout);
if (!ret)
return -ETIME;
if (ret > 0 && !timeout)
return 0;
return ret;
}
static int print_sched_attr(const struct i915_sched_attr *attr,
char *buf, int x, int len)
{

5
drivers/gpu/drm/i915/i915_request.h
View File

@ -414,6 +414,11 @@ void i915_request_unsubmit(struct i915_request *request);
void i915_request_cancel(struct i915_request *rq, int error);
long i915_request_wait_timeout(struct i915_request *rq,
unsigned int flags,
long timeout)
__attribute__((nonnull(1)));
long i915_request_wait(struct i915_request *rq,
unsigned int flags,
long timeout)