From patchwork Fri Jul 13 08:38:03 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chris Wilson X-Patchwork-Id: 10522789 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 813B260245 for ; Fri, 13 Jul 2018 08:38:23 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 7120229686 for ; Fri, 13 Jul 2018 08:38:23 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 645E929817; Fri, 13 Jul 2018 08:38:23 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00, MAILING_LIST_MULTI, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 9C31A29686 for ; Fri, 13 Jul 2018 08:38:22 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 720866F1BC; Fri, 13 Jul 2018 08:38:21 +0000 (UTC) X-Original-To: intel-gfx@lists.freedesktop.org Delivered-To: intel-gfx@lists.freedesktop.org Received: from fireflyinternet.com (mail.fireflyinternet.com [109.228.58.192]) by gabe.freedesktop.org (Postfix) with ESMTPS id 99C356F1BC for ; Fri, 13 Jul 2018 08:38:19 +0000 (UTC) X-Default-Received-SPF: pass (skip=forwardok (res=PASS)) x-ip-name=78.156.65.138; Received: from haswell.alporthouse.com (unverified [78.156.65.138]) by fireflyinternet.com (Firefly Internet (M1)) with ESMTP id 12339877-1500050 for multiple; Fri, 13 Jul 2018 09:37:56 +0100 From: Chris Wilson To: intel-gfx@lists.freedesktop.org Date: Fri, 13 Jul 2018 09:38:03 +0100 Message-Id: <20180713083803.4520-1-chris@chris-wilson.co.uk> X-Mailer: git-send-email 2.18.0 Subject: [Intel-gfx] [PATCH] drm/i915/execlists: Drop clear_gtiir() on GPU reset X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" X-Virus-Scanned: ClamAV using ClamSMTP With the new CSB processing code, we are not vulnerable to delayed delivery of a pre-reset interrupt as we use the CSB status pointers in the HWSP to decide if we need to parse any CSB events and no longer need to wait for the first post-reset interrupt to be assured that the CSB mmio registers are valid. The new icl code to clear registers has a nasty lock inversion: [ 57.409776] ====================================================== [ 57.409779] WARNING: possible circular locking dependency detected [ 57.409783] 4.18.0-rc4-CI-CI_DII_1137+ #1 Tainted: G U W [ 57.409785] ------------------------------------------------------ [ 57.409788] swapper/6/0 is trying to acquire lock: [ 57.409790] 000000004f304ee5 (&engine->timeline.lock/1){-.-.}, at: execlists_submit_request+0x2b/0x1a0 [i915] [ 57.409841] but task is already holding lock: [ 57.409844] 00000000aad89594 (&(&rq->lock)->rlock#2){-.-.}, at: notify_ring+0x2b2/0x480 [i915] [ 57.409869] which lock already depends on the new lock. [ 57.409872] the existing dependency chain (in reverse order) is: [ 57.409876] -> #2 (&(&rq->lock)->rlock#2){-.-.}: [ 57.409900] notify_ring+0x2b2/0x480 [i915] [ 57.409922] gen8_cs_irq_handler+0x39/0xa0 [i915] [ 57.409943] gen11_irq_handler+0x2f0/0x420 [i915] [ 57.409949] __handle_irq_event_percpu+0x42/0x370 [ 57.409952] handle_irq_event_percpu+0x2b/0x70 [ 57.409956] handle_irq_event+0x2f/0x50 [ 57.409959] handle_edge_irq+0xe7/0x190 [ 57.409964] handle_irq+0x67/0x160 [ 57.409967] do_IRQ+0x5e/0x120 [ 57.409971] ret_from_intr+0x0/0x1d [ 57.409974] _raw_spin_unlock_irqrestore+0x4e/0x60 [ 57.409979] tasklet_action_common.isra.5+0x47/0xb0 [ 57.409982] __do_softirq+0xd9/0x505 [ 57.409985] irq_exit+0xa9/0xc0 [ 57.409988] do_IRQ+0x9a/0x120 [ 57.409991] ret_from_intr+0x0/0x1d [ 57.409995] cpuidle_enter_state+0xac/0x360 [ 57.409999] do_idle+0x1f3/0x250 [ 57.410004] cpu_startup_entry+0x6a/0x70 [ 57.410010] start_secondary+0x19d/0x1f0 [ 57.410015] secondary_startup_64+0xa5/0xb0 [ 57.410018] -> #1 (&(&dev_priv->irq_lock)->rlock){-.-.}: [ 57.410081] clear_gtiir+0x30/0x200 [i915] [ 57.410116] execlists_reset+0x6e/0x2b0 [i915] [ 57.410140] i915_reset_engine+0x111/0x190 [i915] [ 57.410165] i915_handle_error+0x11a/0x4a0 [i915] [ 57.410198] i915_hangcheck_elapsed+0x378/0x530 [i915] [ 57.410204] process_one_work+0x248/0x6c0 [ 57.410207] worker_thread+0x37/0x380 [ 57.410211] kthread+0x119/0x130 [ 57.410215] ret_from_fork+0x3a/0x50 [ 57.410217] -> #0 (&engine->timeline.lock/1){-.-.}: [ 57.410224] _raw_spin_lock_irqsave+0x33/0x50 [ 57.410256] execlists_submit_request+0x2b/0x1a0 [i915] [ 57.410289] submit_notify+0x8d/0x124 [i915] [ 57.410314] __i915_sw_fence_complete+0x81/0x250 [i915] [ 57.410339] dma_i915_sw_fence_wake+0xd/0x20 [i915] [ 57.410344] dma_fence_signal_locked+0x79/0x200 [ 57.410368] notify_ring+0x2ba/0x480 [i915] [ 57.410392] gen8_cs_irq_handler+0x39/0xa0 [i915] [ 57.410416] gen11_irq_handler+0x2f0/0x420 [i915] [ 57.410421] __handle_irq_event_percpu+0x42/0x370 [ 57.410425] handle_irq_event_percpu+0x2b/0x70 [ 57.410428] handle_irq_event+0x2f/0x50 [ 57.410432] handle_edge_irq+0xe7/0x190 [ 57.410436] handle_irq+0x67/0x160 [ 57.410439] do_IRQ+0x5e/0x120 [ 57.410445] ret_from_intr+0x0/0x1d [ 57.410449] cpuidle_enter_state+0xac/0x360 [ 57.410453] do_idle+0x1f3/0x250 [ 57.410456] cpu_startup_entry+0x6a/0x70 [ 57.410460] start_secondary+0x19d/0x1f0 [ 57.410464] secondary_startup_64+0xa5/0xb0 [ 57.410466] other info that might help us debug this: [ 57.410471] Chain exists of: &engine->timeline.lock/1 --> &(&dev_priv->irq_lock)->rlock --> &(&rq->lock)->rlock#2 [ 57.410481] Possible unsafe locking scenario: [ 57.410485] CPU0 CPU1 [ 57.410487] ---- ---- [ 57.410490] lock(&(&rq->lock)->rlock#2); [ 57.410494] lock(&(&dev_priv->irq_lock)->rlock); [ 57.410498] lock(&(&rq->lock)->rlock#2); [ 57.410503] lock(&engine->timeline.lock/1); [ 57.410506] *** DEADLOCK *** [ 57.410511] 4 locks held by swapper/6/0: [ 57.410514] #0: 0000000074575789 (&(&dev_priv->irq_lock)->rlock){-.-.}, at: gen11_irq_handler+0x8a/0x420 [i915] [ 57.410542] #1: 000000009b29b30e (rcu_read_lock){....}, at: notify_ring+0x1a/0x480 [i915] [ 57.410573] #2: 00000000aad89594 (&(&rq->lock)->rlock#2){-.-.}, at: notify_ring+0x2b2/0x480 [i915] [ 57.410601] #3: 000000009b29b30e (rcu_read_lock){....}, at: submit_notify+0x35/0x124 [i915] [ 57.410635] stack backtrace: [ 57.410640] CPU: 6 PID: 0 Comm: swapper/6 Tainted: G U W 4.18.0-rc4-CI-CI_DII_1137+ #1 [ 57.410644] Hardware name: Intel Corporation Ice Lake Client Platform/IceLake U DDR4 SODIMM PD RVP, BIOS ICLSFWR1.R00.2222.A01.1805300339 05/30/2018 [ 57.410650] Call Trace: [ 57.410652] [ 57.410657] dump_stack+0x67/0x9b [ 57.410662] print_circular_bug.isra.16+0x1c8/0x2b0 [ 57.410666] __lock_acquire+0x1897/0x1b50 [ 57.410671] ? lock_acquire+0xa6/0x210 [ 57.410674] lock_acquire+0xa6/0x210 [ 57.410706] ? execlists_submit_request+0x2b/0x1a0 [i915] [ 57.410711] _raw_spin_lock_irqsave+0x33/0x50 [ 57.410741] ? execlists_submit_request+0x2b/0x1a0 [i915] [ 57.410769] execlists_submit_request+0x2b/0x1a0 [i915] [ 57.410774] ? _raw_spin_unlock_irqrestore+0x39/0x60 [ 57.410804] submit_notify+0x8d/0x124 [i915] [ 57.410828] __i915_sw_fence_complete+0x81/0x250 [i915] [ 57.410854] dma_i915_sw_fence_wake+0xd/0x20 [i915] [ 57.410858] dma_fence_signal_locked+0x79/0x200 [ 57.410882] notify_ring+0x2ba/0x480 [i915] [ 57.410907] gen8_cs_irq_handler+0x39/0xa0 [i915] [ 57.410933] gen11_irq_handler+0x2f0/0x420 [i915] [ 57.410938] __handle_irq_event_percpu+0x42/0x370 [ 57.410943] handle_irq_event_percpu+0x2b/0x70 [ 57.410947] handle_irq_event+0x2f/0x50 [ 57.410951] handle_edge_irq+0xe7/0x190 [ 57.410955] handle_irq+0x67/0x160 [ 57.410958] do_IRQ+0x5e/0x120 [ 57.410962] common_interrupt+0xf/0xf [ 57.410965] [ 57.410969] RIP: 0010:cpuidle_enter_state+0xac/0x360 [ 57.410972] Code: 44 00 00 31 ff e8 84 93 91 ff 45 84 f6 74 12 9c 58 f6 c4 02 0f 85 31 02 00 00 31 ff e8 7d 30 98 ff e8 e8 0e 94 ff fb 4c 29 fb <48> ba cf f7 53 e3 a5 9b c4 20 48 89 d8 48 c1 fb 3f 48 f7 ea b8 ff [ 57.411015] RSP: 0018:ffffc90000133e90 EFLAGS: 00000216 ORIG_RAX: ffffffffffffffdd [ 57.411023] RAX: ffff8804ae748040 RBX: 000000000002a97d RCX: 0000000000000000 [ 57.411029] RDX: 0000000000000046 RSI: ffffffff82141263 RDI: ffffffff820f05a7 [ 57.411035] RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000000 [ 57.411041] R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff8229f078 [ 57.411045] R13: ffff8804ab2adfa8 R14: 0000000000000000 R15: 0000000d5de092e3 [ 57.411052] do_idle+0x1f3/0x250 [ 57.411055] cpu_startup_entry+0x6a/0x70 [ 57.411059] start_secondary+0x19d/0x1f0 [ 57.411064] secondary_startup_64+0xa5/0xb0 The easiest remedy is to remove the defunct code. Fixes: ff047a87cfac ("drm/i915/icl: Correctly clear lost ctx-switch interrupts across reset for Gen11") References: fd8526e50902 ("drm/i915/execlists: Trust the CSB") Signed-off-by: Chris Wilson Cc: Michel Thierry Cc: Oscar Mateo Cc: Tvrtko Ursulin Cc: Daniele Ceraolo Spurio Reviewed-by: Michel Thierry --- drivers/gpu/drm/i915/intel_lrc.c | 68 -------------------------------- 1 file changed, 68 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c index 35d37af0cb9a..8fd8de71c2b5 100644 --- a/drivers/gpu/drm/i915/intel_lrc.c +++ b/drivers/gpu/drm/i915/intel_lrc.c @@ -795,72 +795,6 @@ execlists_cancel_port_requests(struct intel_engine_execlists * const execlists) execlists_user_end(execlists); } -static void clear_gtiir(struct intel_engine_cs *engine) -{ - struct drm_i915_private *dev_priv = engine->i915; - int i; - - /* - * Clear any pending interrupt state. - * - * We do it twice out of paranoia that some of the IIR are - * double buffered, and so if we only reset it once there may - * still be an interrupt pending. - */ - if (INTEL_GEN(dev_priv) >= 11) { - static const struct { - u8 bank; - u8 bit; - } gen11_gtiir[] = { - [RCS] = {0, GEN11_RCS0}, - [BCS] = {0, GEN11_BCS}, - [_VCS(0)] = {1, GEN11_VCS(0)}, - [_VCS(1)] = {1, GEN11_VCS(1)}, - [_VCS(2)] = {1, GEN11_VCS(2)}, - [_VCS(3)] = {1, GEN11_VCS(3)}, - [_VECS(0)] = {1, GEN11_VECS(0)}, - [_VECS(1)] = {1, GEN11_VECS(1)}, - }; - unsigned long irqflags; - - GEM_BUG_ON(engine->id >= ARRAY_SIZE(gen11_gtiir)); - - spin_lock_irqsave(&dev_priv->irq_lock, irqflags); - for (i = 0; i < 2; i++) { - gen11_reset_one_iir(dev_priv, - gen11_gtiir[engine->id].bank, - gen11_gtiir[engine->id].bit); - } - spin_unlock_irqrestore(&dev_priv->irq_lock, irqflags); - } else { - static const u8 gtiir[] = { - [RCS] = 0, - [BCS] = 0, - [VCS] = 1, - [VCS2] = 1, - [VECS] = 3, - }; - - GEM_BUG_ON(engine->id >= ARRAY_SIZE(gtiir)); - - for (i = 0; i < 2; i++) { - I915_WRITE(GEN8_GT_IIR(gtiir[engine->id]), - engine->irq_keep_mask); - POSTING_READ(GEN8_GT_IIR(gtiir[engine->id])); - } - GEM_BUG_ON(I915_READ(GEN8_GT_IIR(gtiir[engine->id])) & - engine->irq_keep_mask); - } -} - -static void reset_irq(struct intel_engine_cs *engine) -{ - /* Mark all CS interrupts as complete */ - smp_store_mb(engine->execlists.active, 0); - - clear_gtiir(engine); -} - static void reset_csb_pointers(struct intel_engine_execlists *execlists) { /* @@ -904,7 +838,6 @@ static void execlists_cancel_requests(struct intel_engine_cs *engine) /* Cancel the requests on the HW and clear the ELSP tracker. */ execlists_cancel_port_requests(execlists); - reset_irq(engine); /* Mark all executing requests as skipped. */ list_for_each_entry(rq, &engine->timeline.requests, link) { @@ -1975,7 +1908,6 @@ static void execlists_reset(struct intel_engine_cs *engine, * requests were completed. */ execlists_cancel_port_requests(execlists); - reset_irq(engine); /* Push back any incomplete requests for replay after the reset. */ __unwind_incomplete_requests(engine);