On 10/24/2024 08:18, Nirmoy Das wrote:
Flush xe ordered_wq in case of ufence timeout which is observed
on LNL and that points to the 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 E core
scheduling fix.
v2: Add platform check(Himal)
s/__flush_workqueue/flush_workqueue(Jani)
Cc: Badal Nilawar <badal.nilawar@xxxxxxxxx>
Cc: Jani Nikula <jani.nikula@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 | 14 ++++++++++++++
1 file changed, 14 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..78a0ad3c78fe 100644
--- a/drivers/gpu/drm/xe/xe_wait_user_fence.c
+++ b/drivers/gpu/drm/xe/xe_wait_user_fence.c
@@ -13,6 +13,7 @@
#include "xe_device.h"
#include "xe_gt.h"
#include "xe_macros.h"
+#include "compat-i915-headers/i915_drv.h"
#include "xe_exec_queue.h"
static int do_compare(u64 addr, u64 value, u64 mask, u16 op)
@@ -155,6 +156,19 @@ int xe_wait_user_fence_ioctl(struct drm_device *dev, void *data,
}
if (!timeout) {
+ if (IS_LUNARLAKE(xe)) {
+ /*
+ * 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);
If we are having multiple instances of this workaround, can we wrap them
up in as 'LNL_FLUSH_WORKQUEUE(q)' or some such? Put the IS_LNL check
inside the macro and make it pretty obvious exactly where all the
instances are by having a single macro name to search for.
John.
+ err = do_compare(addr, args->value, args->mask, args->op);
+ if (err <= 0)
+ break;
+ }
err = -ETIME;
break;
}