From patchwork Tue Apr 20 10:34:50 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Maarten Lankhorst X-Patchwork-Id: 12213691 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 00CDAC43460 for ; Tue, 20 Apr 2021 10:35:01 +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 94DCC61008 for ; Tue, 20 Apr 2021 10:35:00 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 94DCC61008 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.com 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 D01956E7D7; Tue, 20 Apr 2021 10:34:57 +0000 (UTC) Received: from mblankhorst.nl (mblankhorst.nl [IPv6:2a02:2308::216:3eff:fe92:dfa3]) by gabe.freedesktop.org (Postfix) with ESMTPS id EA6C789C60; Tue, 20 Apr 2021 10:34:55 +0000 (UTC) From: Maarten Lankhorst To: intel-gfx@lists.freedesktop.org Date: Tue, 20 Apr 2021 12:34:50 +0200 Message-Id: <20210420103451.408059-1-maarten.lankhorst@linux.intel.com> X-Mailer: git-send-email 2.31.0 MIME-Version: 1.0 Subject: [Intel-gfx] [PATCH 1/2] drm/i915: Remove asynchronous vma binding 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: Daniel Vetter , dri-devel@lists.freedesktop.org Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" Commit e3793468b466 ("drm/i915: Use the async worker to avoid reclaim tainting the ggtt->mutex") moves the vma binding to dma_fence_work, but dma_fence_work has has signalling fence semantics. On braswell, we can call stop_machine inside fence_work, causing a splat because memory allocation inside stop_machine is allowed. This patch does not fix that lockdep splat yet, but will allow the next patch to remove it. Signed-off-by: Maarten Lankhorst Acked-by: Daniel Vetter --- drivers/gpu/drm/i915/gem/i915_gem_stolen.c | 3 - drivers/gpu/drm/i915/gt/gen6_ppgtt.c | 1 - drivers/gpu/drm/i915/gt/gen8_ppgtt.c | 1 - drivers/gpu/drm/i915/gt/intel_ggtt.c | 4 - drivers/gpu/drm/i915/gt/intel_gtt.h | 2 - drivers/gpu/drm/i915/i915_gem.c | 6 - drivers/gpu/drm/i915/i915_vma.c | 174 +++------------------ drivers/gpu/drm/i915/i915_vma.h | 5 +- drivers/gpu/drm/i915/i915_vma_types.h | 3 - 9 files changed, 21 insertions(+), 178 deletions(-) diff --git a/drivers/gpu/drm/i915/gem/i915_gem_stolen.c b/drivers/gpu/drm/i915/gem/i915_gem_stolen.c index b0597de206de..ec04df0a3b89 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_stolen.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_stolen.c @@ -505,9 +505,6 @@ static void dbg_poison(struct i915_ggtt *ggtt, if (!drm_mm_node_allocated(&ggtt->error_capture)) return; - if (ggtt->vm.bind_async_flags & I915_VMA_GLOBAL_BIND) - return; /* beware stop_machine() inversion */ - GEM_BUG_ON(!IS_ALIGNED(size, PAGE_SIZE)); mutex_lock(&ggtt->error_mutex); diff --git a/drivers/gpu/drm/i915/gt/gen6_ppgtt.c b/drivers/gpu/drm/i915/gt/gen6_ppgtt.c index e08dff376339..0c5a9a767849 100644 --- a/drivers/gpu/drm/i915/gt/gen6_ppgtt.c +++ b/drivers/gpu/drm/i915/gt/gen6_ppgtt.c @@ -436,7 +436,6 @@ struct i915_ppgtt *gen6_ppgtt_create(struct intel_gt *gt) ppgtt->base.vm.pd_shift = ilog2(SZ_4K * SZ_4K / sizeof(gen6_pte_t)); ppgtt->base.vm.top = 1; - ppgtt->base.vm.bind_async_flags = I915_VMA_LOCAL_BIND; ppgtt->base.vm.allocate_va_range = gen6_alloc_va_range; ppgtt->base.vm.clear_range = gen6_ppgtt_clear_range; ppgtt->base.vm.insert_entries = gen6_ppgtt_insert_entries; diff --git a/drivers/gpu/drm/i915/gt/gen8_ppgtt.c b/drivers/gpu/drm/i915/gt/gen8_ppgtt.c index 176c19633412..92f8a23e66cc 100644 --- a/drivers/gpu/drm/i915/gt/gen8_ppgtt.c +++ b/drivers/gpu/drm/i915/gt/gen8_ppgtt.c @@ -736,7 +736,6 @@ struct i915_ppgtt *gen8_ppgtt_create(struct intel_gt *gt) goto err_free_pd; } - ppgtt->vm.bind_async_flags = I915_VMA_LOCAL_BIND; ppgtt->vm.insert_entries = gen8_ppgtt_insert; ppgtt->vm.allocate_va_range = gen8_ppgtt_alloc; ppgtt->vm.clear_range = gen8_ppgtt_clear; diff --git a/drivers/gpu/drm/i915/gt/intel_ggtt.c b/drivers/gpu/drm/i915/gt/intel_ggtt.c index 670c1271e7d5..e1ec6edae1fb 100644 --- a/drivers/gpu/drm/i915/gt/intel_ggtt.c +++ b/drivers/gpu/drm/i915/gt/intel_ggtt.c @@ -127,7 +127,6 @@ void i915_ggtt_suspend(struct i915_ggtt *ggtt) list_for_each_entry_safe(vma, vn, &ggtt->vm.bound_list, vm_link) { GEM_BUG_ON(!drm_mm_node_allocated(&vma->node)); - i915_vma_wait_for_bind(vma); if (i915_vma_is_pinned(vma)) continue; @@ -671,7 +670,6 @@ static int init_aliasing_ppgtt(struct i915_ggtt *ggtt) ppgtt->vm.allocate_va_range(&ppgtt->vm, &stash, 0, ggtt->vm.total); ggtt->alias = ppgtt; - ggtt->vm.bind_async_flags |= ppgtt->vm.bind_async_flags; GEM_BUG_ON(ggtt->vm.vma_ops.bind_vma != ggtt_bind_vma); ggtt->vm.vma_ops.bind_vma = aliasing_gtt_bind_vma; @@ -911,8 +909,6 @@ static int gen8_gmch_probe(struct i915_ggtt *ggtt) IS_CHERRYVIEW(i915) /* fails with concurrent use/update */) { ggtt->vm.insert_entries = bxt_vtd_ggtt_insert_entries__BKL; ggtt->vm.insert_page = bxt_vtd_ggtt_insert_page__BKL; - ggtt->vm.bind_async_flags = - I915_VMA_GLOBAL_BIND | I915_VMA_LOCAL_BIND; } ggtt->invalidate = gen8_ggtt_invalidate; diff --git a/drivers/gpu/drm/i915/gt/intel_gtt.h b/drivers/gpu/drm/i915/gt/intel_gtt.h index e67e34e17913..d9d2ca8b4b61 100644 --- a/drivers/gpu/drm/i915/gt/intel_gtt.h +++ b/drivers/gpu/drm/i915/gt/intel_gtt.h @@ -230,8 +230,6 @@ struct i915_address_space { u64 total; /* size addr space maps (ex. 2GB for ggtt) */ u64 reserved; /* size addr space reserved */ - unsigned int bind_async_flags; - /* * Each active user context has its own address space (in full-ppgtt). * Since the vm may be shared between multiple contexts, we count how diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c index b23f58e94cfb..4639c47c038b 100644 --- a/drivers/gpu/drm/i915/i915_gem.c +++ b/drivers/gpu/drm/i915/i915_gem.c @@ -946,12 +946,6 @@ i915_gem_object_ggtt_pin_ww(struct drm_i915_gem_object *obj, mutex_unlock(&ggtt->vm.mutex); } - ret = i915_vma_wait_for_bind(vma); - if (ret) { - i915_vma_unpin(vma); - return ERR_PTR(ret); - } - return vma; } diff --git a/drivers/gpu/drm/i915/i915_vma.c b/drivers/gpu/drm/i915/i915_vma.c index 07490db51cdc..e4b2590d41ce 100644 --- a/drivers/gpu/drm/i915/i915_vma.c +++ b/drivers/gpu/drm/i915/i915_vma.c @@ -289,79 +289,6 @@ i915_vma_instance(struct drm_i915_gem_object *obj, return vma; } -struct i915_vma_work { - struct dma_fence_work base; - struct i915_address_space *vm; - struct i915_vm_pt_stash stash; - struct i915_vma *vma; - struct drm_i915_gem_object *pinned; - struct i915_sw_dma_fence_cb cb; - enum i915_cache_level cache_level; - unsigned int flags; -}; - -static int __vma_bind(struct dma_fence_work *work) -{ - struct i915_vma_work *vw = container_of(work, typeof(*vw), base); - struct i915_vma *vma = vw->vma; - - vma->ops->bind_vma(vw->vm, &vw->stash, - vma, vw->cache_level, vw->flags); - return 0; -} - -static void __vma_release(struct dma_fence_work *work) -{ - struct i915_vma_work *vw = container_of(work, typeof(*vw), base); - - if (vw->pinned) { - __i915_gem_object_unpin_pages(vw->pinned); - i915_gem_object_put(vw->pinned); - } - - i915_vm_free_pt_stash(vw->vm, &vw->stash); - i915_vm_put(vw->vm); -} - -static const struct dma_fence_work_ops bind_ops = { - .name = "bind", - .work = __vma_bind, - .release = __vma_release, -}; - -struct i915_vma_work *i915_vma_work(void) -{ - struct i915_vma_work *vw; - - vw = kzalloc(sizeof(*vw), GFP_KERNEL); - if (!vw) - return NULL; - - dma_fence_work_init(&vw->base, &bind_ops); - vw->base.dma.error = -EAGAIN; /* disable the worker by default */ - - return vw; -} - -int i915_vma_wait_for_bind(struct i915_vma *vma) -{ - int err = 0; - - if (rcu_access_pointer(vma->active.excl.fence)) { - struct dma_fence *fence; - - rcu_read_lock(); - fence = dma_fence_get_rcu_safe(&vma->active.excl.fence); - rcu_read_unlock(); - if (fence) { - err = dma_fence_wait(fence, MAX_SCHEDULE_TIMEOUT); - dma_fence_put(fence); - } - } - - return err; -} - /** * i915_vma_bind - Sets up PTEs for an VMA in it's corresponding address space. * @vma: VMA to map @@ -375,8 +302,7 @@ int i915_vma_wait_for_bind(struct i915_vma *vma) */ int i915_vma_bind(struct i915_vma *vma, enum i915_cache_level cache_level, - u32 flags, - struct i915_vma_work *work) + u32 flags, struct i915_vm_pt_stash *stash) { u32 bind_flags; u32 vma_flags; @@ -405,39 +331,7 @@ int i915_vma_bind(struct i915_vma *vma, GEM_BUG_ON(!vma->pages); trace_i915_vma_bind(vma, bind_flags); - if (work && bind_flags & vma->vm->bind_async_flags) { - struct dma_fence *prev; - - work->vma = vma; - work->cache_level = cache_level; - work->flags = bind_flags; - - /* - * Note we only want to chain up to the migration fence on - * the pages (not the object itself). As we don't track that, - * yet, we have to use the exclusive fence instead. - * - * Also note that we do not want to track the async vma as - * part of the obj->resv->excl_fence as it only affects - * execution and not content or object's backing store lifetime. - */ - prev = i915_active_set_exclusive(&vma->active, &work->base.dma); - if (prev) { - __i915_sw_fence_await_dma_fence(&work->base.chain, - prev, - &work->cb); - dma_fence_put(prev); - } - - work->base.dma.error = 0; /* enable the queue_work() */ - - if (vma->obj) { - __i915_gem_object_pin_pages(vma->obj); - work->pinned = i915_gem_object_get(vma->obj); - } - } else { - vma->ops->bind_vma(vma->vm, NULL, vma, cache_level, bind_flags); - } + vma->ops->bind_vma(vma->vm, stash, vma, cache_level, bind_flags); atomic_or(bind_flags, &vma->flags); return 0; @@ -531,9 +425,6 @@ bool i915_vma_misplaced(const struct i915_vma *vma, if (!drm_mm_node_allocated(&vma->node)) return false; - if (test_bit(I915_VMA_ERROR_BIT, __i915_vma_flags(vma))) - return true; - if (vma->node.size < size) return true; @@ -752,7 +643,7 @@ static bool try_qad_pin(struct i915_vma *vma, unsigned int flags) if (unlikely(flags & ~bound)) return false; - if (unlikely(bound & (I915_VMA_OVERFLOW | I915_VMA_ERROR))) + if (unlikely(bound & I915_VMA_OVERFLOW)) return false; if (!(bound & I915_VMA_PIN_MASK)) @@ -770,7 +661,7 @@ static bool try_qad_pin(struct i915_vma *vma, unsigned int flags) */ mutex_lock(&vma->vm->mutex); do { - if (unlikely(bound & (I915_VMA_OVERFLOW | I915_VMA_ERROR))) { + if (unlikely(bound & I915_VMA_OVERFLOW)) { pinned = false; break; } @@ -857,10 +748,10 @@ static void vma_unbind_pages(struct i915_vma *vma) int i915_vma_pin_ww(struct i915_vma *vma, struct i915_gem_ww_ctx *ww, u64 size, u64 alignment, u64 flags) { - struct i915_vma_work *work = NULL; intel_wakeref_t wakeref = 0; unsigned int bound; int err; + struct i915_vm_pt_stash stash = {}; #ifdef CONFIG_PROVE_LOCKING if (debug_locks && !WARN_ON(!ww) && vma->resv) @@ -883,33 +774,21 @@ int i915_vma_pin_ww(struct i915_vma *vma, struct i915_gem_ww_ctx *ww, if (flags & PIN_GLOBAL) wakeref = intel_runtime_pm_get(&vma->vm->i915->runtime_pm); - if (flags & vma->vm->bind_async_flags) { - /* lock VM */ - err = i915_vm_lock_objects(vma->vm, ww); + if (vma->vm->allocate_va_range) { + err = i915_vm_alloc_pt_stash(vma->vm, + &stash, + vma->size); if (err) goto err_rpm; - work = i915_vma_work(); - if (!work) { - err = -ENOMEM; + err = i915_vm_lock_objects(vma->vm, ww); + if (err) goto err_rpm; - } - work->vm = i915_vm_get(vma->vm); - - /* Allocate enough page directories to used PTE */ - if (vma->vm->allocate_va_range) { - err = i915_vm_alloc_pt_stash(vma->vm, - &work->stash, - vma->size); - if (err) - goto err_fence; - - err = i915_vm_pin_pt_stash(vma->vm, - &work->stash); - if (err) - goto err_fence; - } + err = i915_vm_pin_pt_stash(vma->vm, + &stash); + if (err) + goto err_rpm; } /* @@ -932,7 +811,7 @@ int i915_vma_pin_ww(struct i915_vma *vma, struct i915_gem_ww_ctx *ww, err = mutex_lock_interruptible_nested(&vma->vm->mutex, !(flags & PIN_GLOBAL)); if (err) - goto err_fence; + goto err_rpm; /* No more allocations allowed now we hold vm->mutex */ @@ -942,11 +821,6 @@ int i915_vma_pin_ww(struct i915_vma *vma, struct i915_gem_ww_ctx *ww, } bound = atomic_read(&vma->flags); - if (unlikely(bound & I915_VMA_ERROR)) { - err = -ENOMEM; - goto err_unlock; - } - if (unlikely(!((bound + 1) & I915_VMA_PIN_MASK))) { err = -EAGAIN; /* pins are meant to be fairly temporary */ goto err_unlock; @@ -973,7 +847,7 @@ int i915_vma_pin_ww(struct i915_vma *vma, struct i915_gem_ww_ctx *ww, GEM_BUG_ON(!vma->pages); err = i915_vma_bind(vma, vma->obj ? vma->obj->cache_level : 0, - flags, work); + flags, &stash); if (err) goto err_remove; @@ -996,10 +870,8 @@ int i915_vma_pin_ww(struct i915_vma *vma, struct i915_gem_ww_ctx *ww, i915_active_release(&vma->active); err_unlock: mutex_unlock(&vma->vm->mutex); -err_fence: - if (work) - dma_fence_work_commit_imm(&work->base); err_rpm: + i915_vm_free_pt_stash(vma->vm, &stash); if (wakeref) intel_runtime_pm_put(&vma->vm->i915->runtime_pm, wakeref); vma_put_pages(vma); @@ -1034,14 +906,8 @@ int i915_ggtt_pin(struct i915_vma *vma, struct i915_gem_ww_ctx *ww, err = i915_vma_pin_ww(vma, ww, 0, align, flags | PIN_GLOBAL); else err = i915_vma_pin(vma, 0, align, flags | PIN_GLOBAL); - if (err != -ENOSPC) { - if (!err) { - err = i915_vma_wait_for_bind(vma); - if (err) - i915_vma_unpin(vma); - } + if (err != -ENOSPC) return err; - } /* Unlike i915_vma_pin, we don't take no for an answer! */ flush_idle_contexts(vm->gt); @@ -1306,7 +1172,7 @@ void __i915_vma_evict(struct i915_vma *vma) trace_i915_vma_unbind(vma); vma->ops->unbind_vma(vma->vm, vma); } - atomic_and(~(I915_VMA_BIND_MASK | I915_VMA_ERROR | I915_VMA_GGTT_WRITE), + atomic_and(~(I915_VMA_BIND_MASK | I915_VMA_GGTT_WRITE), &vma->flags); i915_vma_detach(vma); diff --git a/drivers/gpu/drm/i915/i915_vma.h b/drivers/gpu/drm/i915/i915_vma.h index 8df784a026d2..d1d0fc76ef99 100644 --- a/drivers/gpu/drm/i915/i915_vma.h +++ b/drivers/gpu/drm/i915/i915_vma.h @@ -195,11 +195,10 @@ i915_vma_compare(struct i915_vma *vma, return memcmp(&vma->ggtt_view.partial, &view->partial, view->type); } -struct i915_vma_work *i915_vma_work(void); int i915_vma_bind(struct i915_vma *vma, enum i915_cache_level cache_level, u32 flags, - struct i915_vma_work *work); + struct i915_vm_pt_stash *stash); bool i915_gem_valid_gtt_space(struct i915_vma *vma, unsigned long color); bool i915_vma_misplaced(const struct i915_vma *vma, @@ -418,8 +417,6 @@ struct i915_vma *i915_vma_make_unshrinkable(struct i915_vma *vma); void i915_vma_make_shrinkable(struct i915_vma *vma); void i915_vma_make_purgeable(struct i915_vma *vma); -int i915_vma_wait_for_bind(struct i915_vma *vma); - static inline int i915_vma_sync(struct i915_vma *vma) { /* Wait for the asynchronous bindings and pending GPU reads */ diff --git a/drivers/gpu/drm/i915/i915_vma_types.h b/drivers/gpu/drm/i915/i915_vma_types.h index 6b1bfa230b82..82868a755a96 100644 --- a/drivers/gpu/drm/i915/i915_vma_types.h +++ b/drivers/gpu/drm/i915/i915_vma_types.h @@ -240,9 +240,6 @@ struct i915_vma { #define I915_VMA_ALLOC_BIT 12 -#define I915_VMA_ERROR_BIT 13 -#define I915_VMA_ERROR ((int)BIT(I915_VMA_ERROR_BIT)) - #define I915_VMA_GGTT_BIT 14 #define I915_VMA_CAN_FENCE_BIT 15 #define I915_VMA_USERFAULT_BIT 16 From patchwork Tue Apr 20 10:34:51 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Maarten Lankhorst X-Patchwork-Id: 12213689 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4C4B6C433B4 for ; Tue, 20 Apr 2021 10:34:58 +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 DC6B961002 for ; Tue, 20 Apr 2021 10:34:57 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DC6B961002 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.com 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 39F9A6E5D1; Tue, 20 Apr 2021 10:34:57 +0000 (UTC) Received: from mblankhorst.nl (mblankhorst.nl [IPv6:2a02:2308::216:3eff:fe92:dfa3]) by gabe.freedesktop.org (Postfix) with ESMTPS id EB07C6E5D1; Tue, 20 Apr 2021 10:34:55 +0000 (UTC) From: Maarten Lankhorst To: intel-gfx@lists.freedesktop.org Date: Tue, 20 Apr 2021 12:34:51 +0200 Message-Id: <20210420103451.408059-2-maarten.lankhorst@linux.intel.com> X-Mailer: git-send-email 2.31.0 In-Reply-To: <20210420103451.408059-1-maarten.lankhorst@linux.intel.com> References: <20210420103451.408059-1-maarten.lankhorst@linux.intel.com> MIME-Version: 1.0 Subject: [Intel-gfx] [PATCH 2/2] drm/i915: Use trylock in shrinker for ggtt on bsw vt-d and bxt, v2. 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" The stop_machine() lock may allocate memory, but is called inside vm->mutex, which is taken in the shrinker. This will cause a lockdep splat, as can be seen below: <4>[ 462.585762] ====================================================== <4>[ 462.585768] WARNING: possible circular locking dependency detected <4>[ 462.585773] 5.12.0-rc5-CI-Trybot_7644+ #1 Tainted: G U <4>[ 462.585779] ------------------------------------------------------ <4>[ 462.585783] i915_selftest/5540 is trying to acquire lock: <4>[ 462.585788] ffffffff826440b0 (cpu_hotplug_lock){++++}-{0:0}, at: stop_machine+0x12/0x30 <4>[ 462.585814] but task is already holding lock: <4>[ 462.585818] ffff888125369c70 (&vm->mutex/1){+.+.}-{3:3}, at: i915_vma_pin_ww+0x38e/0xb40 [i915] <4>[ 462.586301] which lock already depends on the new lock. <4>[ 462.586305] the existing dependency chain (in reverse order) is: <4>[ 462.586309] -> #2 (&vm->mutex/1){+.+.}-{3:3}: <4>[ 462.586323] i915_gem_shrinker_taints_mutex+0x2d/0x50 [i915] <4>[ 462.586719] i915_address_space_init+0x12d/0x130 [i915] <4>[ 462.587092] ppgtt_init+0x4e/0x80 [i915] <4>[ 462.587467] gen8_ppgtt_create+0x3e/0x5c0 [i915] <4>[ 462.587828] i915_ppgtt_create+0x28/0xf0 [i915] <4>[ 462.588203] intel_gt_init+0x123/0x370 [i915] <4>[ 462.588572] i915_gem_init+0x129/0x1f0 [i915] <4>[ 462.588971] i915_driver_probe+0x753/0xd80 [i915] <4>[ 462.589320] i915_pci_probe+0x43/0x1d0 [i915] <4>[ 462.589671] pci_device_probe+0x9e/0x110 <4>[ 462.589680] really_probe+0xea/0x410 <4>[ 462.589690] driver_probe_device+0xd9/0x140 <4>[ 462.589697] device_driver_attach+0x4a/0x50 <4>[ 462.589704] __driver_attach+0x83/0x140 <4>[ 462.589711] bus_for_each_dev+0x75/0xc0 <4>[ 462.589718] bus_add_driver+0x14b/0x1f0 <4>[ 462.589724] driver_register+0x66/0xb0 <4>[ 462.589731] i915_init+0x70/0x87 [i915] <4>[ 462.590053] do_one_initcall+0x56/0x2e0 <4>[ 462.590061] do_init_module+0x55/0x200 <4>[ 462.590068] load_module+0x2703/0x2990 <4>[ 462.590074] __do_sys_finit_module+0xad/0x110 <4>[ 462.590080] do_syscall_64+0x33/0x80 <4>[ 462.590089] entry_SYSCALL_64_after_hwframe+0x44/0xae <4>[ 462.590096] -> #1 (fs_reclaim){+.+.}-{0:0}: <4>[ 462.590109] fs_reclaim_acquire+0x9f/0xd0 <4>[ 462.590118] kmem_cache_alloc_trace+0x3d/0x430 <4>[ 462.590126] intel_cpuc_prepare+0x3b/0x1b0 <4>[ 462.590133] cpuhp_invoke_callback+0x9e/0x890 <4>[ 462.590141] _cpu_up+0xa4/0x130 <4>[ 462.590147] cpu_up+0x82/0x90 <4>[ 462.590153] bringup_nonboot_cpus+0x4a/0x60 <4>[ 462.590159] smp_init+0x21/0x5c <4>[ 462.590167] kernel_init_freeable+0x8a/0x1b7 <4>[ 462.590175] kernel_init+0x5/0xff <4>[ 462.590181] ret_from_fork+0x22/0x30 <4>[ 462.590187] -> #0 (cpu_hotplug_lock){++++}-{0:0}: <4>[ 462.590199] __lock_acquire+0x1520/0x2590 <4>[ 462.590207] lock_acquire+0xd1/0x3d0 <4>[ 462.590213] cpus_read_lock+0x39/0xc0 <4>[ 462.590219] stop_machine+0x12/0x30 <4>[ 462.590226] bxt_vtd_ggtt_insert_entries__BKL+0x36/0x50 [i915] <4>[ 462.590601] ggtt_bind_vma+0x5d/0x80 [i915] <4>[ 462.590970] i915_vma_bind+0xdc/0x1c0 [i915] <4>[ 462.591374] i915_vma_pin_ww+0x435/0xb40 [i915] <4>[ 462.591779] make_obj_busy+0xcb/0x330 [i915] <4>[ 462.592170] igt_mmap_offset_exhaustion+0x45f/0x4c0 [i915] <4>[ 462.592562] __i915_subtests.cold.7+0x42/0x92 [i915] <4>[ 462.592995] __run_selftests.part.3+0x10d/0x172 [i915] <4>[ 462.593428] i915_live_selftests.cold.5+0x1f/0x47 [i915] <4>[ 462.593860] i915_pci_probe+0x93/0x1d0 [i915] <4>[ 462.594210] pci_device_probe+0x9e/0x110 <4>[ 462.594217] really_probe+0xea/0x410 <4>[ 462.594226] driver_probe_device+0xd9/0x140 <4>[ 462.594233] device_driver_attach+0x4a/0x50 <4>[ 462.594240] __driver_attach+0x83/0x140 <4>[ 462.594247] bus_for_each_dev+0x75/0xc0 <4>[ 462.594254] bus_add_driver+0x14b/0x1f0 <4>[ 462.594260] driver_register+0x66/0xb0 <4>[ 462.594267] i915_init+0x70/0x87 [i915] <4>[ 462.594586] do_one_initcall+0x56/0x2e0 <4>[ 462.594592] do_init_module+0x55/0x200 <4>[ 462.594599] load_module+0x2703/0x2990 <4>[ 462.594605] __do_sys_finit_module+0xad/0x110 <4>[ 462.594612] do_syscall_64+0x33/0x80 <4>[ 462.594618] entry_SYSCALL_64_after_hwframe+0x44/0xae <4>[ 462.594625] other info that might help us debug this: <4>[ 462.594629] Chain exists of: cpu_hotplug_lock --> fs_reclaim --> &vm->mutex/1 <4>[ 462.594645] Possible unsafe locking scenario: <4>[ 462.594648] CPU0 CPU1 <4>[ 462.594652] ---- ---- <4>[ 462.594655] lock(&vm->mutex/1); <4>[ 462.594664] lock(fs_reclaim); <4>[ 462.594671] lock(&vm->mutex/1); <4>[ 462.594679] lock(cpu_hotplug_lock); <4>[ 462.594686] *** DEADLOCK *** <4>[ 462.594690] 4 locks held by i915_selftest/5540: <4>[ 462.594696] #0: ffff888100fbc240 (&dev->mutex){....}-{3:3}, at: device_driver_attach+0x18/0x50 <4>[ 462.594715] #1: ffffc900006cb9a0 (reservation_ww_class_acquire){+.+.}-{0:0}, at: make_obj_busy+0x81/0x330 [i915] <4>[ 462.595118] #2: ffff88812a6081e8 (reservation_ww_class_mutex){+.+.}-{3:3}, at: make_obj_busy+0x21f/0x330 [i915] <4>[ 462.595519] #3: ffff888125369c70 (&vm->mutex/1){+.+.}-{3:3}, at: i915_vma_pin_ww+0x38e/0xb40 [i915] <4>[ 462.595934] stack backtrace: <4>[ 462.595939] CPU: 0 PID: 5540 Comm: i915_selftest Tainted: G U 5.12.0-rc5-CI-Trybot_7644+ #1 <4>[ 462.595947] Hardware name: GOOGLE Kefka/Kefka, BIOS MrChromebox 02/04/2018 <4>[ 462.595952] Call Trace: <4>[ 462.595961] dump_stack+0x7f/0xad <4>[ 462.595974] check_noncircular+0x12e/0x150 <4>[ 462.595982] ? save_stack.isra.17+0x3f/0x70 <4>[ 462.595991] ? drm_mm_insert_node_in_range+0x34a/0x5b0 <4>[ 462.596000] ? i915_vma_pin_ww+0x9ec/0xb40 [i915] <4>[ 462.596410] __lock_acquire+0x1520/0x2590 <4>[ 462.596419] ? do_init_module+0x55/0x200 <4>[ 462.596429] lock_acquire+0xd1/0x3d0 <4>[ 462.596435] ? stop_machine+0x12/0x30 <4>[ 462.596445] ? gen8_ggtt_insert_entries+0xf0/0xf0 [i915] <4>[ 462.596816] cpus_read_lock+0x39/0xc0 <4>[ 462.596824] ? stop_machine+0x12/0x30 <4>[ 462.596831] stop_machine+0x12/0x30 <4>[ 462.596839] bxt_vtd_ggtt_insert_entries__BKL+0x36/0x50 [i915] <4>[ 462.597210] ggtt_bind_vma+0x5d/0x80 [i915] <4>[ 462.597580] i915_vma_bind+0xdc/0x1c0 [i915] <4>[ 462.597986] i915_vma_pin_ww+0x435/0xb40 [i915] <4>[ 462.598395] ? make_obj_busy+0xcb/0x330 [i915] <4>[ 462.598786] make_obj_busy+0xcb/0x330 [i915] <4>[ 462.599180] ? 0xffffffff81000000 <4>[ 462.599187] ? debug_mutex_unlock+0x50/0xa0 <4>[ 462.599198] igt_mmap_offset_exhaustion+0x45f/0x4c0 [i915] <4>[ 462.599592] __i915_subtests.cold.7+0x42/0x92 [i915] <4>[ 462.600026] ? i915_perf_selftests+0x20/0x20 [i915] <4>[ 462.600422] ? __i915_nop_setup+0x10/0x10 [i915] <4>[ 462.600820] __run_selftests.part.3+0x10d/0x172 [i915] <4>[ 462.601253] i915_live_selftests.cold.5+0x1f/0x47 [i915] <4>[ 462.601686] i915_pci_probe+0x93/0x1d0 [i915] <4>[ 462.602037] ? _raw_spin_unlock_irqrestore+0x3d/0x60 <4>[ 462.602047] pci_device_probe+0x9e/0x110 <4>[ 462.602057] really_probe+0xea/0x410 <4>[ 462.602067] driver_probe_device+0xd9/0x140 <4>[ 462.602075] device_driver_attach+0x4a/0x50 <4>[ 462.602084] __driver_attach+0x83/0x140 <4>[ 462.602091] ? device_driver_attach+0x50/0x50 <4>[ 462.602099] ? device_driver_attach+0x50/0x50 <4>[ 462.602107] bus_for_each_dev+0x75/0xc0 <4>[ 462.602116] bus_add_driver+0x14b/0x1f0 <4>[ 462.602124] driver_register+0x66/0xb0 <4>[ 462.602133] i915_init+0x70/0x87 [i915] <4>[ 462.602453] ? 0xffffffffa0606000 <4>[ 462.602458] do_one_initcall+0x56/0x2e0 <4>[ 462.602466] ? kmem_cache_alloc_trace+0x374/0x430 <4>[ 462.602476] do_init_module+0x55/0x200 <4>[ 462.602484] load_module+0x2703/0x2990 <4>[ 462.602500] ? __do_sys_finit_module+0xad/0x110 <4>[ 462.602507] __do_sys_finit_module+0xad/0x110 <4>[ 462.602519] do_syscall_64+0x33/0x80 <4>[ 462.602527] entry_SYSCALL_64_after_hwframe+0x44/0xae <4>[ 462.602535] RIP: 0033:0x7fab69d8d89d Changes since v1: - Add lockdep annotations during init, to ensure that lockdep is primed. This also fixes a false positive when reading /proc/lockdep_stats during module reload. Signed-off-by: Maarten Lankhorst --- drivers/gpu/drm/i915/gem/i915_gem_shrinker.c | 13 +++++++++---- drivers/gpu/drm/i915/gt/intel_ggtt.c | 8 +++++--- drivers/gpu/drm/i915/gt/intel_gtt.c | 17 ++++++++++++++++- drivers/gpu/drm/i915/i915_drv.h | 11 +++++++++-- drivers/gpu/drm/i915/i915_gem.c | 15 +++++++++++++-- 5 files changed, 52 insertions(+), 12 deletions(-) diff --git a/drivers/gpu/drm/i915/gem/i915_gem_shrinker.c b/drivers/gpu/drm/i915/gem/i915_gem_shrinker.c index 3e248d3bd869..7545ddd83659 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_shrinker.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_shrinker.c @@ -38,15 +38,17 @@ static bool can_release_pages(struct drm_i915_gem_object *obj) } static bool unsafe_drop_pages(struct drm_i915_gem_object *obj, - unsigned long shrink) + unsigned long shrink, bool trylock_vm) { unsigned long flags; flags = 0; if (shrink & I915_SHRINK_ACTIVE) - flags = I915_GEM_OBJECT_UNBIND_ACTIVE; + flags |= I915_GEM_OBJECT_UNBIND_ACTIVE; if (!(shrink & I915_SHRINK_BOUND)) - flags = I915_GEM_OBJECT_UNBIND_TEST; + flags |= I915_GEM_OBJECT_UNBIND_TEST; + if (trylock_vm) + flags |= I915_GEM_OBJECT_UNBIND_VM_TRYLOCK; if (i915_gem_object_unbind(obj, flags) == 0) return true; @@ -116,6 +118,9 @@ i915_gem_shrink(struct i915_gem_ww_ctx *ww, unsigned long scanned = 0; int err; + /* CHV + VTD workaround use stop_machine(); need to trylock vm->mutex */ + bool trylock_vm = !ww && intel_vm_no_concurrent_access_wa(i915); + trace_i915_gem_shrink(i915, target, shrink); /* @@ -203,7 +208,7 @@ i915_gem_shrink(struct i915_gem_ww_ctx *ww, spin_unlock_irqrestore(&i915->mm.obj_lock, flags); err = 0; - if (unsafe_drop_pages(obj, shrink)) { + if (unsafe_drop_pages(obj, shrink, trylock_vm)) { /* May arrive from get_pages on another bo */ if (!ww) { if (!i915_gem_object_trylock(obj)) diff --git a/drivers/gpu/drm/i915/gt/intel_ggtt.c b/drivers/gpu/drm/i915/gt/intel_ggtt.c index e1ec6edae1fb..e6e6efacab87 100644 --- a/drivers/gpu/drm/i915/gt/intel_ggtt.c +++ b/drivers/gpu/drm/i915/gt/intel_ggtt.c @@ -904,9 +904,11 @@ static int gen8_gmch_probe(struct i915_ggtt *ggtt) ggtt->vm.insert_entries = gen8_ggtt_insert_entries; - /* Serialize GTT updates with aperture access on BXT if VT-d is on. */ - if (intel_ggtt_update_needs_vtd_wa(i915) || - IS_CHERRYVIEW(i915) /* fails with concurrent use/update */) { + /* + * Serialize GTT updates with aperture access on BXT if VT-d is on, + * and always on CHV. + */ + if (intel_vm_no_concurrent_access_wa(i915)) { ggtt->vm.insert_entries = bxt_vtd_ggtt_insert_entries__BKL; ggtt->vm.insert_page = bxt_vtd_ggtt_insert_page__BKL; } diff --git a/drivers/gpu/drm/i915/gt/intel_gtt.c b/drivers/gpu/drm/i915/gt/intel_gtt.c index 941f8af016d6..a994234f2bd4 100644 --- a/drivers/gpu/drm/i915/gt/intel_gtt.c +++ b/drivers/gpu/drm/i915/gt/intel_gtt.c @@ -132,7 +132,22 @@ void i915_address_space_init(struct i915_address_space *vm, int subclass) */ mutex_init(&vm->mutex); lockdep_set_subclass(&vm->mutex, subclass); - i915_gem_shrinker_taints_mutex(vm->i915, &vm->mutex); + + if (!intel_vm_no_concurrent_access_wa(vm->i915)) { + i915_gem_shrinker_taints_mutex(vm->i915, &vm->mutex); + } else { + /* + * CHV + BXT VTD workaround use stop_machine(), + * which is allowed to allocate memory. This means &vm->mutex + * is the outer lock, and in theory we can allocate memory inside + * it through stop_machine(). + * + * Add the annotation for this, we use trylock in shrinker. + */ + mutex_acquire(&vm->mutex.dep_map, 0, 0, _THIS_IP_); + might_alloc(GFP_KERNEL); + mutex_release(&vm->mutex.dep_map, _THIS_IP_); + } dma_resv_init(&vm->resv); GEM_BUG_ON(!vm->total); diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h index e20294e9227a..4ef4f45dfb49 100644 --- a/drivers/gpu/drm/i915/i915_drv.h +++ b/drivers/gpu/drm/i915/i915_drv.h @@ -1712,9 +1712,15 @@ static inline bool intel_scanout_needs_vtd_wa(struct drm_i915_private *dev_priv) } static inline bool -intel_ggtt_update_needs_vtd_wa(struct drm_i915_private *dev_priv) +intel_ggtt_update_needs_vtd_wa(struct drm_i915_private *i915) { - return IS_BROXTON(dev_priv) && intel_vtd_active(); + return IS_BROXTON(i915) && intel_vtd_active(); +} + +static inline bool +intel_vm_no_concurrent_access_wa(struct drm_i915_private *i915) +{ + return IS_CHERRYVIEW(i915) || intel_ggtt_update_needs_vtd_wa(i915); } /* i915_drv.c */ @@ -1794,6 +1800,7 @@ int i915_gem_object_unbind(struct drm_i915_gem_object *obj, #define I915_GEM_OBJECT_UNBIND_ACTIVE BIT(0) #define I915_GEM_OBJECT_UNBIND_BARRIER BIT(1) #define I915_GEM_OBJECT_UNBIND_TEST BIT(2) +#define I915_GEM_OBJECT_UNBIND_VM_TRYLOCK BIT(3) void i915_gem_runtime_suspend(struct drm_i915_private *dev_priv); diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c index 4639c47c038b..dcf91a12172f 100644 --- a/drivers/gpu/drm/i915/i915_gem.c +++ b/drivers/gpu/drm/i915/i915_gem.c @@ -157,8 +157,19 @@ int i915_gem_object_unbind(struct drm_i915_gem_object *obj, if (vma) { ret = -EBUSY; if (flags & I915_GEM_OBJECT_UNBIND_ACTIVE || - !i915_vma_is_active(vma)) - ret = i915_vma_unbind(vma); + !i915_vma_is_active(vma)) { + if (i915_is_ggtt(vma->vm) && + flags & I915_GEM_OBJECT_UNBIND_VM_TRYLOCK) { + if (mutex_trylock(&vma->vm->mutex)) { + ret = __i915_vma_unbind(vma); + mutex_unlock(&vma->vm->mutex); + } else { + ret = -EBUSY; + } + } else { + ret = i915_vma_unbind(vma); + } + } __i915_vma_put(vma); }