Reapply "drm/qxl: simplify qxl_fence_wait"

This reverts commit 07ed11afb6.

Stephen Rostedt reports:
 "I went to run my tests on my VMs and the tests hung on boot up.
  Unfortunately, the most I ever got out was:

  [   93.607888] Testing event system initcall: OK
  [   93.667730] Running tests on all trace events:
  [   93.669757] Testing all events: OK
  [   95.631064] ------------[ cut here ]------------
  Timed out after 60 seconds"

and further debugging points to a possible circular locking dependency
between the console_owner locking and the worker pool locking.

Reverting the commit allows Steve's VM to boot to completion again.

[ This may obviously result in the "[TTM] Buffer eviction failed"
  messages again, which was the reason for that original revert. But at
  this point this seems preferable to a non-booting system... ]

Reported-and-bisected-by: Steven Rostedt <rostedt@goodmis.org>
Link: https://lore.kernel.org/all/20240502081641.457aa25f@gandalf.local.home/
Acked-by: Maxime Ripard <mripard@kernel.org>
Cc: Alex Constantino <dreaming.about.electric.sheep@gmail.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Timo Lindfors <timo.lindfors@iki.fi>
Cc: Dave Airlie <airlied@redhat.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Linus Torvalds 2024-05-06 13:28:59 -07:00
parent ee5b455b0a
commit 3628e0383d
2 changed files with 5 additions and 52 deletions

View File

@ -58,56 +58,16 @@ static long qxl_fence_wait(struct dma_fence *fence, bool intr,
signed long timeout)
{
struct qxl_device *qdev;
struct qxl_release *release;
int count = 0, sc = 0;
bool have_drawable_releases;
unsigned long cur, end = jiffies + timeout;
qdev = container_of(fence->lock, struct qxl_device, release_lock);
release = container_of(fence, struct qxl_release, base);
have_drawable_releases = release->type == QXL_RELEASE_DRAWABLE;
retry:
sc++;
if (!wait_event_timeout(qdev->release_event,
(dma_fence_is_signaled(fence) ||
(qxl_io_notify_oom(qdev), 0)),
timeout))
return 0;
if (dma_fence_is_signaled(fence))
goto signaled;
qxl_io_notify_oom(qdev);
for (count = 0; count < 11; count++) {
if (!qxl_queue_garbage_collect(qdev, true))
break;
if (dma_fence_is_signaled(fence))
goto signaled;
}
if (dma_fence_is_signaled(fence))
goto signaled;
if (have_drawable_releases || sc < 4) {
if (sc > 2)
/* back off */
usleep_range(500, 1000);
if (time_after(jiffies, end))
return 0;
if (have_drawable_releases && sc > 300) {
DMA_FENCE_WARN(fence,
"failed to wait on release %llu after spincount %d\n",
fence->context & ~0xf0000000, sc);
goto signaled;
}
goto retry;
}
/*
* yeah, original sync_obj_wait gave up after 3 spins when
* have_drawable_releases is not set.
*/
signaled:
cur = jiffies;
if (time_after(cur, end))
return 0;

View File

@ -682,11 +682,4 @@ static inline bool dma_fence_is_container(struct dma_fence *fence)
return dma_fence_is_array(fence) || dma_fence_is_chain(fence);
}
#define DMA_FENCE_WARN(f, fmt, args...) \
do { \
struct dma_fence *__ff = (f); \
pr_warn("f %llu#%llu: " fmt, __ff->context, __ff->seqno,\
##args); \
} while (0)
#endif /* __LINUX_DMA_FENCE_H */