On 28.10.2022 12:06, Tvrtko Ursulin wrote:
Hi,I can't really provide feedback on the GuC interactions so only some superficial comments below.On 28/10/2022 10:34, Andrzej Hajda wrote:Bad GPU memory accesses can result in catastrophic error notifications being send from the GPU to the KMD via the GuC. Add a handler to process the notification by printing a kernel message and dumping the related engine state (if appropriate). Since the same CAT error can be reported twice, log only 1st one and assume error for the same context reported in less than 100ms after the 1st one is duplicated. Signed-off-by: Andrzej Hajda <andrzej.ha...@intel.com> --- .../gpu/drm/i915/gt/uc/abi/guc_actions_abi.h | 1 + drivers/gpu/drm/i915/gt/uc/intel_guc.h | 2 + drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c | 3 ++ .../gpu/drm/i915/gt/uc/intel_guc_submission.c | 47 +++++++++++++++++++ 4 files changed, 53 insertions(+)diff --git a/drivers/gpu/drm/i915/gt/uc/abi/guc_actions_abi.h b/drivers/gpu/drm/i915/gt/uc/abi/guc_actions_abi.hindex f359bef046e0b2..f9a1c5642855e3 100644 --- a/drivers/gpu/drm/i915/gt/uc/abi/guc_actions_abi.h +++ b/drivers/gpu/drm/i915/gt/uc/abi/guc_actions_abi.h @@ -138,6 +138,7 @@ enum intel_guc_action { INTEL_GUC_ACTION_REGISTER_CONTEXT_MULTI_LRC = 0x4601, INTEL_GUC_ACTION_CLIENT_SOFT_RESET = 0x5507, INTEL_GUC_ACTION_SET_ENG_UTIL_BUFF = 0x550A, + INTEL_GUC_ACTION_NOTIFY_MEMORY_CAT_ERROR = 0x6000, INTEL_GUC_ACTION_STATE_CAPTURE_NOTIFICATION = 0x8002, INTEL_GUC_ACTION_NOTIFY_FLUSH_LOG_BUFFER_TO_FILE = 0x8003, INTEL_GUC_ACTION_NOTIFY_CRASH_DUMP_POSTED = 0x8004,diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc.h b/drivers/gpu/drm/i915/gt/uc/intel_guc.hindex 804133df1ac9b4..61b412732d095a 100644 --- a/drivers/gpu/drm/i915/gt/uc/intel_guc.h +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc.h@@ -445,6 +445,8 @@ int intel_guc_engine_failure_process_msg(struct intel_guc *guc,const u32 *msg, u32 len); int intel_guc_error_capture_process_msg(struct intel_guc *guc, const u32 *msg, u32 len); +int intel_guc_cat_error_process_msg(struct intel_guc *guc, + const u32 *msg, u32 len); struct intel_engine_cs *intel_guc_lookup_engine(struct intel_guc *guc, u8 guc_class, u8 instance); diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c b/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.cindex 2b22065e87bf9a..f55f724e264407 100644 --- a/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c@@ -1035,6 +1035,9 @@ static int ct_process_request(struct intel_guc_ct *ct, struct ct_incoming_msg *rCT_ERROR(ct, "Received GuC exception notification!\n"); ret = 0; break; + case INTEL_GUC_ACTION_NOTIFY_MEMORY_CAT_ERROR: + ret = intel_guc_cat_error_process_msg(guc, payload, len); + break; default: ret = -EOPNOTSUPP; break;diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.cindex 693b07a977893d..f68ae4a0ad864d 100644 --- a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c@@ -4659,6 +4659,53 @@ int intel_guc_engine_failure_process_msg(struct intel_guc *guc,return 0; } +int intel_guc_cat_error_process_msg(struct intel_guc *guc, + const u32 *msg, u32 len) +{ + static struct { + u32 ctx_id; + unsigned long after; + } ratelimit; + struct drm_i915_private *i915 = guc_to_gt(guc)->i915; + struct drm_printer p = drm_info_printer(i915->drm.dev); + struct intel_context *ce; + unsigned long flags; + u32 ctx_id; + + if (unlikely(len != 1)) { + drm_dbg(&i915->drm, "Invalid length %u\n", len); + return -EPROTO; + } + ctx_id = msg[0]; ++ if (ctx_id == ratelimit.ctx_id && time_is_after_jiffies(ratelimit.after))+ return 0;This will be suboptimal with multi-gpu and multi-tile. Not sure if ratelimiting is needed,
In many cases they comes in pairs: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_12313/bat-adln-1/igt@i915_selftest@l...@hugepages.html#dmesg-warnings510 https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_12304/bat-rpls-2/igt@i915_selftest@l...@hugepages.html#dmesg-warnings514 https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_12298/bat-rpls-1/igt@i915_selftest@l...@hugepages.html#dmesg-warnings553And since CAT error usually (always???) means engine hang, they apparently both indicate the same error.
but if it is, then perhaps move the state into struct intel_guc?
Or intel_context or intel_engine_cs, then it logs will be avoided till reset of the engine?
It becomes complicated now, I just wanted only better log message :)
Would it be worth counting the rate limited ones and then log how many were not logged when the next one is logged?
I have no idea why there are two messages, for me it looks like just some redundancy. engine state is exactly the same in both cases.
Should the condition be inverted - !time_is_after?
time_is_after_jiffies(arg) means that the time pointed by arg did not come yet (arg > jiffies, ie it is after jiffies), so it looks OK, but it is misleading.
+ + ratelimit.ctx_id = ctx_id; + ratelimit.after = jiffies + msecs_to_jiffies(100); + + if (unlikely(ctx_id == -1)) { + drm_err(&i915->drm,+ "GPU reported catastrophic error without providing valid context\n");+ return 0; + } + + xa_lock_irqsave(&guc->context_lookup, flags);The only caller seems to be a worker so just _irq I guess. ct_process_incoming_requests has the same issue but I haven't looked into other handlers called from ct_process_request.+ ce = g2h_context_lookup(guc, ctx_id); + if (ce) + intel_context_get(ce); + xa_unlock_irqrestore(&guc->context_lookup, flags); + if (unlikely(!ce)) + return -EPROTO;EPROTO seems incorrect - message could have just been delayed and context deregistered I think. Probably you just need to still log the error just say context couldn't be resolved. GuC experts to confirm or deny.
Copy/pasted from intel_guc_context_reset_process_msg, but you are right. On the other hand hung context should not fly too far away.
++ drm_err(&i915->drm, "GPU reported catastrophic error associated with context %u on %s\n",+ ctx_id, ce->engine->name); + intel_engine_dump(ce->engine, &p, "%s\n", ce->engine->name);Same as above, when CT channel is congested this can be delayed and then I wonder what's the point of dumping engine state. In fact, even when CT is not congested the delay could be significant enough for it to be pointless. Another question for GuC experts I guess.Also, check if intel_engine_dump can handle ce->engine being a virtual engine.
I've added engine_dump to look at which instruction CAT occurred, did not help too much in my case, but maybe in other cases it can be helpful.
I though also about adding: guc_log_context(p, ce) guc_log_context_priority(p, ce)Or even whole body of the loop in intel_guc_submission_print_context_info, after exporting it to some helper, but atm I have no idea if it can be helpfull.
Regards Andrzej
Regards, Tvrtko+ intel_context_put(ce); + + return 0; +} + void intel_guc_find_hung_context(struct intel_engine_cs *engine) { struct intel_guc *guc = &engine->gt->uc.guc;
