Currently in some testcases we can trigger:
[drm] *ERROR* GT0: SCHED_DONE: Unexpected engine state 0x02b1, guc_id=8, runnable_state=0
[drm] *ERROR* GT0: G2H action 0x1002 failed (-EPROTO) len 3 msg 02 10 00 90 08 00 00 00 00 00 00 00
Looking at a snippet of corresponding ftrace for this GuC id we can see:
498.852891: xe_sched_msg_add: dev=0000:03:00.0, gt=0 guc_id=8, opcode=3
498.854083: xe_sched_msg_recv: dev=0000:03:00.0, gt=0 guc_id=8, opcode=3
498.855389: xe_exec_queue_kill: dev=0000:03:00.0, 5:0x1, gt=0, width=1, guc_id=8, guc_state=0x3, flags=0x0
498.855436: xe_exec_queue_lr_cleanup: dev=0000:03:00.0, 5:0x1, gt=0, width=1, guc_id=8, guc_state=0x83, flags=0x0
498.856767: xe_exec_queue_close: dev=0000:03:00.0, 5:0x1, gt=0, width=1, guc_id=8, guc_state=0x83, flags=0x0
498.862889: xe_exec_queue_scheduling_disable: dev=0000:03:00.0, 5:0x1, gt=0, width=1, guc_id=8, guc_state=0xa9, flags=0x0
498.863032: xe_exec_queue_scheduling_disable: dev=0000:03:00.0, 5:0x1, gt=0, width=1, guc_id=8, guc_state=0x2b9, flags=0x0
498.875596: xe_exec_queue_scheduling_done: dev=0000:03:00.0, 5:0x1, gt=0, width=1, guc_id=8, guc_state=0x2b9, flags=0x0
498.875604: xe_exec_queue_deregister: dev=0000:03:00.0, 5:0x1, gt=0, width=1, guc_id=8, guc_state=0x2b1, flags=0x0
499.074483: xe_exec_queue_deregister_done: dev=0000:03:00.0, 5:0x1, gt=0, width=1, guc_id=8, guc_state=0x2b1, flags=0x0
This looks to be the two scheduling_disable racing with each other, one
from the suspend (opcode=3) and then again during lr cleanup. While
those two operations are serialized, the G2H portion is not, therefore
when marking the queue as pending_disabled and then firing off the first
request, we proceed do the same again, however the first disable
response only fires after this which then clears the pending_disabled.
At this point the second comes back and is processed, however the
pending_disabled is no longer set, hence triggering the warning.
To fix this wait for pending_disabled when doing the lr cleanup and
calling disable_scheduling_deregister. Also do the same for all other
disable_scheduling callers.
Fixes: dd08ebf6c352 ("drm/xe: Introduce a new DRM driver for Intel GPUs")
Closes: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/3515
Signed-off-by: Matthew Auld <matthew.auld@xxxxxxxxx>
Cc: Matthew Brost <matthew.brost@xxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx> # v6.8+
---
drivers/gpu/drm/xe/xe_guc_submit.c | 16 ++++++++++------
1 file changed, 10 insertions(+), 6 deletions(-)
diff --git a/drivers/gpu/drm/xe/xe_guc_submit.c b/drivers/gpu/drm/xe/xe_guc_submit.c
index f9ecee5364d8..f3c22b101916 100644
--- a/drivers/gpu/drm/xe/xe_guc_submit.c
+++ b/drivers/gpu/drm/xe/xe_guc_submit.c
@@ -767,12 +767,15 @@ static void disable_scheduling_deregister(struct xe_guc *guc,
set_min_preemption_timeout(guc, q);
smp_rmb();
- ret = wait_event_timeout(guc->ct.wq, !exec_queue_pending_enable(q) ||
- xe_guc_read_stopped(guc), HZ * 5);
+ ret = wait_event_timeout(guc->ct.wq,
+ (!exec_queue_pending_enable(q) &&
+ !exec_queue_pending_disable(q)) ||
+ xe_guc_read_stopped(guc),
+ HZ * 5);
if (!ret) {
struct xe_gpu_scheduler *sched = &q->guc->sched;
- xe_gt_warn(q->gt, "Pending enable failed to respond\n");
+ xe_gt_warn(q->gt, "Pending enable/disable failed to respond\n");
xe_sched_submission_start(sched);
xe_gt_reset_async(q->gt);
xe_sched_tdr_queue_imm(sched);
@@ -1099,7 +1102,8 @@ guc_exec_queue_timedout_job(struct drm_sched_job *drm_job)
* modifying state
*/
ret = wait_event_timeout(guc->ct.wq,
- !exec_queue_pending_enable(q) ||
+ (!exec_queue_pending_enable(q) &&
+ !exec_queue_pending_disable(q)) ||
xe_guc_read_stopped(guc), HZ * 5);
if (!ret || xe_guc_read_stopped(guc))
goto trigger_reset;
@@ -1329,8 +1333,8 @@ static void __guc_exec_queue_process_msg_suspend(struct xe_sched_msg *msg)
if (guc_exec_queue_allowed_to_change_state(q) && !exec_queue_suspended(q) &&
exec_queue_enabled(q)) {
- wait_event(guc->ct.wq, q->guc->resume_time != RESUME_PENDING ||
- xe_guc_read_stopped(guc));
+ wait_event(guc->ct.wq, (q->guc->resume_time != RESUME_PENDING ||
+ xe_guc_read_stopped(guc)) && !exec_queue_pending_disable(q));
if (!xe_guc_read_stopped(guc)) {
s64 since_resume_ms =
--
2.47.0
