From patchwork Tue Jan 17 21:36:27 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: John Harrison X-Patchwork-Id: 13105074 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 6CC5BC54E76 for ; Tue, 17 Jan 2023 21:37:06 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 60A9910E12C; Tue, 17 Jan 2023 21:36:57 +0000 (UTC) Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) by gabe.freedesktop.org (Postfix) with ESMTPS id 46E9510E088; Tue, 17 Jan 2023 21:36:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1673991414; x=1705527414; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=6rKX0yXeVxyjWtrNQHbSm4KFl/Rn6MzlA8FP8hwjL9Y=; b=KhNC6B2xzdnt3xm2pxJOv0SPZztH05hPjeONkX4Ect/xVOSa5cpnG/xx NpEYNsdfTvDU0uaRfrtASrnTpaKYAeKx4RTyCLiRcznpTv96SD2U1/E5u ZWROv858//OCz/bVtm4ZukyxHb/IqJKSdQg7RGX/XFNC0MpkAU+376B4S BfJmagLtUyTiqLs/wtowVii8gNbv18dcIb0B/QMxKsqcqVqgYZH/Q5keE uQ4AyM+bHHTw24cg/8lKPcZy+O9Com7mWvZ0Qq1m4hJkvn/Ml10yfDmc3 OkSwvya1BVwoFuBhk7hbRhVL1BHYbh69xD3OEqUEiPEXNKVtIEimU5aKC Q==; X-IronPort-AV: E=McAfee;i="6500,9779,10593"; a="312696226" X-IronPort-AV: E=Sophos;i="5.97,224,1669104000"; d="scan'208";a="312696226" Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by orsmga101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 17 Jan 2023 13:36:53 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6500,9779,10593"; a="988285023" X-IronPort-AV: E=Sophos;i="5.97,224,1669104000"; d="scan'208";a="988285023" Received: from relo-linux-5.jf.intel.com ([10.165.21.152]) by fmsmga005.fm.intel.com with ESMTP; 17 Jan 2023 13:36:53 -0800 From: John.C.Harrison@Intel.com To: Intel-GFX@Lists.FreeDesktop.Org Date: Tue, 17 Jan 2023 13:36:27 -0800 Message-Id: <20230117213630.2897570-3-John.C.Harrison@Intel.com> X-Mailer: git-send-email 2.39.0 In-Reply-To: <20230117213630.2897570-1-John.C.Harrison@Intel.com> References: <20230117213630.2897570-1-John.C.Harrison@Intel.com> MIME-Version: 1.0 Organization: Intel Corporation (UK) Ltd. - Co. Reg. #1134945 - Pipers Way, Swindon SN3 1RJ Subject: [Intel-gfx] [PATCH v2 2/5] drm/i915: Allow error capture without a request X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: DRI-Devel@Lists.FreeDesktop.Org Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" From: John Harrison There was a report of error captures occurring without any hung context being indicated despite the capture being initiated by a 'hung context notification' from GuC. The problem was not reproducible. However, it is possible to happen if the context in question has no active requests. For example, if the hang was in the context switch itself then the breadcrumb write would have occurred and the KMD would see an idle context. In the interests of attempting to provide as much information as possible about a hang, it seems wise to include the engine info regardless of whether a request was found or not. As opposed to just prentending there was no hang at all. So update the error capture code to always record engine information if an engine is given. Which means updating record_context() to take a context instead of a request (which it only ever used to find the context anyway). And split the request agnostic parts of intel_engine_coredump_add_request() out into a seaprate function. v2: Remove a duplicate 'if' statement (Umesh) and fix a put of a null pointer. v3: Tidy up request locking code flow (Tvrtko) Signed-off-by: John Harrison Reviewed-by: Umesh Nerlige Ramappa Acked-by: Tvrtko Ursulin --- drivers/gpu/drm/i915/i915_gpu_error.c | 69 ++++++++++++++++++--------- 1 file changed, 46 insertions(+), 23 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_gpu_error.c b/drivers/gpu/drm/i915/i915_gpu_error.c index 4107a0dfcca7d..461489d599a7e 100644 --- a/drivers/gpu/drm/i915/i915_gpu_error.c +++ b/drivers/gpu/drm/i915/i915_gpu_error.c @@ -1370,14 +1370,14 @@ static void engine_record_execlists(struct intel_engine_coredump *ee) } static bool record_context(struct i915_gem_context_coredump *e, - const struct i915_request *rq) + struct intel_context *ce) { struct i915_gem_context *ctx; struct task_struct *task; bool simulated; rcu_read_lock(); - ctx = rcu_dereference(rq->context->gem_context); + ctx = rcu_dereference(ce->gem_context); if (ctx && !kref_get_unless_zero(&ctx->ref)) ctx = NULL; rcu_read_unlock(); @@ -1396,8 +1396,8 @@ static bool record_context(struct i915_gem_context_coredump *e, e->guilty = atomic_read(&ctx->guilty_count); e->active = atomic_read(&ctx->active_count); - e->total_runtime = intel_context_get_total_runtime_ns(rq->context); - e->avg_runtime = intel_context_get_avg_runtime_ns(rq->context); + e->total_runtime = intel_context_get_total_runtime_ns(ce); + e->avg_runtime = intel_context_get_avg_runtime_ns(ce); simulated = i915_gem_context_no_error_capture(ctx); @@ -1532,15 +1532,37 @@ intel_engine_coredump_alloc(struct intel_engine_cs *engine, gfp_t gfp, u32 dump_ return ee; } +static struct intel_engine_capture_vma * +engine_coredump_add_context(struct intel_engine_coredump *ee, + struct intel_context *ce, + gfp_t gfp) +{ + struct intel_engine_capture_vma *vma = NULL; + + ee->simulated |= record_context(&ee->context, ce); + if (ee->simulated) + return NULL; + + /* + * We need to copy these to an anonymous buffer + * as the simplest method to avoid being overwritten + * by userspace. + */ + vma = capture_vma(vma, ce->ring->vma, "ring", gfp); + vma = capture_vma(vma, ce->state, "HW context", gfp); + + return vma; +} + struct intel_engine_capture_vma * intel_engine_coredump_add_request(struct intel_engine_coredump *ee, struct i915_request *rq, gfp_t gfp) { - struct intel_engine_capture_vma *vma = NULL; + struct intel_engine_capture_vma *vma; - ee->simulated |= record_context(&ee->context, rq); - if (ee->simulated) + vma = engine_coredump_add_context(ee, rq->context, gfp); + if (!vma) return NULL; /* @@ -1550,8 +1572,6 @@ intel_engine_coredump_add_request(struct intel_engine_coredump *ee, */ vma = capture_vma_snapshot(vma, rq->batch_res, gfp, "batch"); vma = capture_user(vma, rq, gfp); - vma = capture_vma(vma, rq->ring->vma, "ring", gfp); - vma = capture_vma(vma, rq->context->state, "HW context", gfp); ee->rq_head = rq->head; ee->rq_post = rq->postfix; @@ -1609,8 +1629,12 @@ capture_engine(struct intel_engine_cs *engine, intel_engine_clear_hung_context(engine); /* This will reference count the request (if found) */ rq = intel_context_find_active_request(ce); - if (!rq || !i915_request_started(rq)) - goto no_request_capture; + if (rq && !i915_request_started(rq)) { + drm_info(&engine->gt->i915->drm, "Got hung context on %s with no active request!\n", + engine->name); + i915_request_put(rq); + rq = NULL; + } } else { /* * Getting here with GuC enabled means it is a forced error capture @@ -1624,25 +1648,24 @@ capture_engine(struct intel_engine_cs *engine, flags); } } - if (!rq) - goto no_request_capture; - - capture = intel_engine_coredump_add_request(ee, rq, ATOMIC_MAYFAIL); - if (!capture) { + if (rq) { + capture = intel_engine_coredump_add_request(ee, rq, ATOMIC_MAYFAIL); i915_request_put(rq); - goto no_request_capture; + } else if (ce) { + capture = engine_coredump_add_context(ee, ce, ATOMIC_MAYFAIL); } + if (dump_flags & CORE_DUMP_FLAG_IS_GUC_CAPTURE) intel_guc_capture_get_matching_node(engine->gt, ee, ce); - intel_engine_coredump_add_vma(ee, capture, compress); - i915_request_put(rq); + if (capture) { + intel_engine_coredump_add_vma(ee, capture, compress); + } else { + kfree(ee); + ee = NULL; + } return ee; - -no_request_capture: - kfree(ee); - return NULL; } static void