From patchwork Wed Aug 5 12:22:12 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Chris Wilson X-Patchwork-Id: 11701839 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 58D0B913 for ; Wed, 5 Aug 2020 12:23:15 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 42D3322D05 for ; Wed, 5 Aug 2020 12:23:15 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 42D3322D05 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=chris-wilson.co.uk Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=intel-gfx-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 591476E5A3; Wed, 5 Aug 2020 12:22:59 +0000 (UTC) X-Original-To: intel-gfx@lists.freedesktop.org Delivered-To: intel-gfx@lists.freedesktop.org Received: from fireflyinternet.com (unknown [77.68.26.236]) by gabe.freedesktop.org (Postfix) with ESMTPS id 025A36E581 for ; Wed, 5 Aug 2020 12:22:52 +0000 (UTC) X-Default-Received-SPF: pass (skip=forwardok (res=PASS)) x-ip-name=78.156.65.138; Received: from build.alporthouse.com (unverified [78.156.65.138]) by fireflyinternet.com (Firefly Internet (M1)) with ESMTP id 22039477-1500050 for multiple; Wed, 05 Aug 2020 13:22:34 +0100 From: Chris Wilson To: intel-gfx@lists.freedesktop.org Date: Wed, 5 Aug 2020 13:22:12 +0100 Message-Id: <20200805122231.23313-19-chris@chris-wilson.co.uk> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200805122231.23313-1-chris@chris-wilson.co.uk> References: <20200805122231.23313-1-chris@chris-wilson.co.uk> MIME-Version: 1.0 Subject: [Intel-gfx] [PATCH 18/37] drm/i915/gem: Separate the ww_mutex walker into its own list 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: =?utf-8?q?Thomas_Hellstr=C3=B6m?= , Chris Wilson Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" In preparation for making eb_vma bigger and heavy to run in parallel, we need to stop applying an in-place swap() to reorder around ww_mutex deadlocks. Keep the array intact and reorder the locks using a dedicated list. Signed-off-by: Chris Wilson Reviewed-by: Tvrtko Ursulin Reviewed-by: Thomas Hellström --- .../gpu/drm/i915/gem/i915_gem_execbuffer.c | 83 ++++++++++++------- 1 file changed, 54 insertions(+), 29 deletions(-) diff --git a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c index 62a1de1dd238..32d23718ee1e 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c @@ -38,6 +38,7 @@ struct eb_vma { struct list_head bind_link; struct list_head unbound_link; struct list_head reloc_link; + struct list_head submit_link; struct hlist_node node; u32 handle; @@ -256,6 +257,8 @@ struct i915_execbuffer { /** list of vma that have execobj.relocation_count */ struct list_head relocs_list; + struct list_head submit_list; + /** * Track the most recently used object for relocations, as we * frequently have to perform multiple relocations within the same @@ -353,6 +356,42 @@ static void eb_vma_array_put(struct eb_vma_array *arr) kref_put(&arr->kref, eb_vma_array_destroy); } +static int +eb_lock_vma(struct i915_execbuffer *eb, struct ww_acquire_ctx *acquire) +{ + struct eb_vma *ev; + int err = 0; + + list_for_each_entry(ev, &eb->submit_list, submit_link) { + struct i915_vma *vma = ev->vma; + + err = ww_mutex_lock_interruptible(&vma->resv->lock, acquire); + if (err == -EDEADLK) { + struct eb_vma *unlock = ev, *en; + + list_for_each_entry_safe_continue_reverse(unlock, en, + &eb->submit_list, + submit_link) { + ww_mutex_unlock(&unlock->vma->resv->lock); + list_move_tail(&unlock->submit_link, &eb->submit_list); + } + + GEM_BUG_ON(!list_is_first(&ev->submit_link, &eb->submit_list)); + err = ww_mutex_lock_slow_interruptible(&vma->resv->lock, + acquire); + } + if (err) { + list_for_each_entry_continue_reverse(ev, + &eb->submit_list, + submit_link) + ww_mutex_unlock(&ev->vma->resv->lock); + break; + } + } + + return err; +} + static int eb_create(struct i915_execbuffer *eb) { /* Allocate an extra slot for use by the command parser + sentinel */ @@ -405,6 +444,10 @@ static int eb_create(struct i915_execbuffer *eb) eb->lut_size = -eb->buffer_count; } + INIT_LIST_HEAD(&eb->bind_list); + INIT_LIST_HEAD(&eb->submit_list); + INIT_LIST_HEAD(&eb->relocs_list); + return 0; } @@ -572,6 +615,7 @@ eb_add_vma(struct i915_execbuffer *eb, } list_add_tail(&ev->bind_link, &eb->bind_list); + list_add_tail(&ev->submit_link, &eb->submit_list); if (entry->relocation_count) list_add_tail(&ev->reloc_link, &eb->relocs_list); @@ -938,9 +982,6 @@ static int eb_lookup_vmas(struct i915_execbuffer *eb) unsigned int i; int err = 0; - INIT_LIST_HEAD(&eb->bind_list); - INIT_LIST_HEAD(&eb->relocs_list); - for (i = 0; i < eb->buffer_count; i++) { struct i915_vma *vma; @@ -1613,38 +1654,19 @@ static int eb_relocate(struct i915_execbuffer *eb) static int eb_move_to_gpu(struct i915_execbuffer *eb) { - const unsigned int count = eb->buffer_count; struct ww_acquire_ctx acquire; - unsigned int i; + struct eb_vma *ev; int err = 0; ww_acquire_init(&acquire, &reservation_ww_class); - for (i = 0; i < count; i++) { - struct eb_vma *ev = &eb->vma[i]; - struct i915_vma *vma = ev->vma; - - err = ww_mutex_lock_interruptible(&vma->resv->lock, &acquire); - if (err == -EDEADLK) { - GEM_BUG_ON(i == 0); - do { - int j = i - 1; - - ww_mutex_unlock(&eb->vma[j].vma->resv->lock); - - swap(eb->vma[i], eb->vma[j]); - } while (--i); + err = eb_lock_vma(eb, &acquire); + if (err) + goto err_fini; - err = ww_mutex_lock_slow_interruptible(&vma->resv->lock, - &acquire); - } - if (err) - break; - } ww_acquire_done(&acquire); - while (i--) { - struct eb_vma *ev = &eb->vma[i]; + list_for_each_entry(ev, &eb->submit_list, submit_link) { struct i915_vma *vma = ev->vma; unsigned int flags = ev->flags; struct drm_i915_gem_object *obj = vma->obj; @@ -1701,6 +1723,8 @@ static int eb_move_to_gpu(struct i915_execbuffer *eb) intel_gt_chipset_flush(eb->engine->gt); return 0; +err_fini: + ww_acquire_fini(&acquire); err_skip: i915_request_set_error_once(eb->request, err); return err; @@ -1956,9 +1980,10 @@ static int eb_parse(struct i915_execbuffer *eb) if (err) goto err_trampoline; - eb->vma[eb->buffer_count].vma = i915_vma_get(shadow); - eb->vma[eb->buffer_count].flags = __EXEC_OBJECT_HAS_PIN; eb->batch = &eb->vma[eb->buffer_count++]; + eb->batch->vma = i915_vma_get(shadow); + eb->batch->flags = __EXEC_OBJECT_HAS_PIN; + list_add_tail(&eb->batch->submit_link, &eb->submit_list); eb->vma[eb->buffer_count].vma = NULL; eb->trampoline = trampoline;