drm/xe/ufence: Wake up waiters after setting ufence->signalled

If a previous ufence is not signalled, vm_bind will return -EBUSY.
Delaying the modification of ufence->signalled can cause issues if the
UMD reuses the same ufence so update ufence->signalled before waking up
waiters.

Cc: Matthew Brost <matthew.brost@intel.com>
Link: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/3233
Fixes: 977e5b82e0 ("drm/xe: Expose user fence from xe_sync_entry")
Reviewed-by: Matthew Brost <matthew.brost@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20241114150537.4161573-1-nirmoy.das@intel.com
Signed-off-by: Nirmoy Das <nirmoy.das@intel.com>
(cherry picked from commit 553a5d14fc)
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
This commit is contained in:
Nirmoy Das
2024-11-14 16:05:37 +01:00
committed by Thomas Hellström
parent 6d9f9115c0
commit 37a1cf288e

View File

@@ -87,8 +87,12 @@ static void user_fence_worker(struct work_struct *w)
drm_dbg(&ufence->xe->drm, "mmget_not_zero() failed, ufence wasn't signaled\n");
}
wake_up_all(&ufence->xe->ufence_wq);
/*
* Wake up waiters only after updating the ufence state, allowing the UMD
* to safely reuse the same ufence without encountering -EBUSY errors.
*/
WRITE_ONCE(ufence->signalled, 1);
wake_up_all(&ufence->xe->ufence_wq);
user_fence_put(ufence);
}