On 10/28/2024 04:49, Nirmoy Das wrote:
I thought the plan was to make this a trackable macro used by all instances of this w/a - LNL_FLUSH_WORK|WORKQUEUE()? With a single, complete description of the problem attached to the macro rather than 'this is similar to' comments scattered through the code.Flush xe ordered_wq in case of ufence timeout which is observed on LNL and that points to recent scheduling issue with E-cores. This is similar to the recent fix: commit e51527233804 ("drm/xe/guc/ct: Flush g2h worker in case of g2h response timeout") and should be removed once there is a E-core scheduling fix for LNL. v2: Add platform check(Himal) s/__flush_workqueue/flush_workqueue(Jani) v3: Remove gfx platform check as the issue related to cpu platform(John) Cc: Badal Nilawar <badal.nilawar@xxxxxxxxx> Cc: Matthew Auld <matthew.auld@xxxxxxxxx> Cc: John Harrison <John.C.Harrison@xxxxxxxxx> Cc: Himal Prasad Ghimiray <himal.prasad.ghimiray@xxxxxxxxx> Cc: Lucas De Marchi <lucas.demarchi@xxxxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> # v6.11+ Link: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/2754 Suggested-by: Matthew Brost <matthew.brost@xxxxxxxxx> Signed-off-by: Nirmoy Das <nirmoy.das@xxxxxxxxx> Reviewed-by: Matthew Brost <matthew.brost@xxxxxxxxx> --- drivers/gpu/drm/xe/xe_wait_user_fence.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/drivers/gpu/drm/xe/xe_wait_user_fence.c b/drivers/gpu/drm/xe/xe_wait_user_fence.c index f5deb81eba01..886c9862d89c 100644 --- a/drivers/gpu/drm/xe/xe_wait_user_fence.c +++ b/drivers/gpu/drm/xe/xe_wait_user_fence.c @@ -155,6 +155,17 @@ int xe_wait_user_fence_ioctl(struct drm_device *dev, void *data, }if (!timeout) {+ /* + * This is analogous to e51527233804 ("drm/xe/guc/ct: Flush g2h worker + * in case of g2h response timeout") + * + * TODO: Drop this change once workqueue scheduling delay issue is + * fixed on LNL Hybrid CPU. + */ + flush_workqueue(xe->ordered_wq);
There was also a request to add a dmesg print if the failing condition was met after doing the flush.
John.
+ err = do_compare(addr, args->value, args->mask, args->op); + if (err <= 0) + break; err = -ETIME; break; }
