From patchwork Fri Nov 20 09:54:42 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Daniel Vetter X-Patchwork-Id: 11919979 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=-18.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, 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 315F8C8300C for ; Fri, 20 Nov 2020 09:56:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DFC0D22244 for ; Fri, 20 Nov 2020 09:56:45 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=ffwll.ch header.i=@ffwll.ch header.b="gbKAYR06" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727801AbgKTJ4l (ORCPT ); Fri, 20 Nov 2020 04:56:41 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46084 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727496AbgKTJ4O (ORCPT ); Fri, 20 Nov 2020 04:56:14 -0500 Received: from mail-wm1-x341.google.com (mail-wm1-x341.google.com [IPv6:2a00:1450:4864:20::341]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CF798C061A49 for ; Fri, 20 Nov 2020 01:56:12 -0800 (PST) Received: by mail-wm1-x341.google.com with SMTP id c9so9770747wml.5 for ; Fri, 20 Nov 2020 01:56:12 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ffwll.ch; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=twJ9Iv0GrWi2HSfwSfV1gOqC9HMYu+pjSEuPdNwPfIY=; b=gbKAYR06usTeKaSMH6KvB92fHlEBNo4+RmCIx3it8RmRuweXViGkHt2NLqQg41aUEm /cdA7UEQtMS2Lfo2xXYvLteOUM15w6L4q4zFzc6iz6hRyia8XL8rj1a+ITjHiVkYOQnz kyhh2EagpE9UkW23wbuldKAJzF6KntErybybI= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=twJ9Iv0GrWi2HSfwSfV1gOqC9HMYu+pjSEuPdNwPfIY=; b=JCVQG2uRqF/djkuaDBiI9ZrgJnVXe/vZ+J/53Qj01FNWzNMm8RM26HzXdW1tWq3P0W QCq/phYiAM2m2bBw6VPhS58siHYAyAjtwjnv+7whV4UcAHQTWq9FObq39v7FUtZET5JE gOMehZ0yl9pFnOYRMMUj6xFaI8R3VO68BvcnCVAHPHkhUvJesNGnrLzBoXn0Ivrb+NxK vwsCwNkVmGUHmr8UVdstZ95WXOflb1M6IXuH59S6XwRMCF6z1sIDDquAbKMS9zqnmPGg clmZpQfG7JkCleixEBuWW2m/ATIBWt05+2RXPZ97LeG1UE43uSxDj7ViHGJvpGg4mSEV v+hQ== X-Gm-Message-State: AOAM532GcAQ+bzyCnWn8RbeQwAl/O+8SDOT8REvtAdVpAmzxNUAWNzFo bSsu3ENTkjbSc6ymn8rRcCWNTQ== X-Google-Smtp-Source: ABdhPJyHPm9O3wkh7JZ6u0DEVaNnU3GqZO5vw/S+tBPm5AXz0/1G/C3ZbR8ZP3R+EG2BDhICxCw1Rg== X-Received: by 2002:a7b:c7d3:: with SMTP id z19mr9261970wmk.4.1605866171520; Fri, 20 Nov 2020 01:56:11 -0800 (PST) Received: from phenom.ffwll.local ([2a02:168:57f4:0:efd0:b9e5:5ae6:c2fa]) by smtp.gmail.com with ESMTPSA id t9sm4500208wrr.49.2020.11.20.01.56.10 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 20 Nov 2020 01:56:10 -0800 (PST) From: Daniel Vetter To: DRI Development Cc: Intel Graphics Development , linux-mm@kvack.org, linux-xfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, LKML , Daniel Vetter , Dave Chinner , Qian Cai , =?utf-8?q?Thomas?= =?utf-8?q?_Hellstr=C3=B6m?= , Andrew Morton , Jason Gunthorpe , linux-rdma@vger.kernel.org, Maarten Lankhorst , =?utf-8?q?Christian_?= =?utf-8?q?K=C3=B6nig?= , "Matthew Wilcox (Oracle)" , Daniel Vetter Subject: [PATCH 1/3] mm: Track mmu notifiers in fs_reclaim_acquire/release Date: Fri, 20 Nov 2020 10:54:42 +0100 Message-Id: <20201120095445.1195585-2-daniel.vetter@ffwll.ch> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201120095445.1195585-1-daniel.vetter@ffwll.ch> References: <20201120095445.1195585-1-daniel.vetter@ffwll.ch> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org fs_reclaim_acquire/release nicely catch recursion issues when allocating GFP_KERNEL memory against shrinkers (which gpu drivers tend to use to keep the excessive caches in check). For mmu notifier recursions we do have lockdep annotations since 23b68395c7c7 ("mm/mmu_notifiers: add a lockdep map for invalidate_range_start/end"). But these only fire if a path actually results in some pte invalidation - for most small allocations that's very rarely the case. The other trouble is that pte invalidation can happen any time when __GFP_RECLAIM is set. Which means only really GFP_ATOMIC is a safe choice, GFP_NOIO isn't good enough to avoid potential mmu notifier recursion. I was pondering whether we should just do the general annotation, but there's always the risk for false positives. Plus I'm assuming that the core fs and io code is a lot better reviewed and tested than random mmu notifier code in drivers. Hence why I decide to only annotate for that specific case. Furthermore even if we'd create a lockdep map for direct reclaim, we'd still need to explicit pull in the mmu notifier map - there's a lot more places that do pte invalidation than just direct reclaim, these two contexts arent the same. Note that the mmu notifiers needing their own independent lockdep map is also the reason we can't hold them from fs_reclaim_acquire to fs_reclaim_release - it would nest with the acquistion in the pte invalidation code, causing a lockdep splat. And we can't remove the annotations from pte invalidation and all the other places since they're called from many other places than page reclaim. Hence we can only do the equivalent of might_lock, but on the raw lockdep map. With this we can also remove the lockdep priming added in 66204f1d2d1b ("mm/mmu_notifiers: prime lockdep") since the new annotations are strictly more powerful. v2: Review from Thomas Hellstrom: - unbotch the fs_reclaim context check, I accidentally inverted it, but it didn't blow up because I inverted it immediately - fix compiling for !CONFIG_MMU_NOTIFIER v3: Unbreak the PF_MEMALLOC_ context flags. Thanks to Qian for the report and Dave for explaining what I failed to see. Cc: linux-fsdevel@vger.kernel.org Cc: Dave Chinner Cc: Qian Cai Cc: linux-xfs@vger.kernel.org Cc: Thomas Hellström (Intel) Cc: Andrew Morton Cc: Jason Gunthorpe Cc: linux-mm@kvack.org Cc: linux-rdma@vger.kernel.org Cc: Maarten Lankhorst Cc: Christian König Cc: "Matthew Wilcox (Oracle)" Signed-off-by: Daniel Vetter Reviewed-by: Jason Gunthorpe --- mm/mmu_notifier.c | 7 ------- mm/page_alloc.c | 31 ++++++++++++++++++++----------- 2 files changed, 20 insertions(+), 18 deletions(-) diff --git a/mm/mmu_notifier.c b/mm/mmu_notifier.c index 5654dd19addc..61ee40ed804e 100644 --- a/mm/mmu_notifier.c +++ b/mm/mmu_notifier.c @@ -612,13 +612,6 @@ int __mmu_notifier_register(struct mmu_notifier *subscription, mmap_assert_write_locked(mm); BUG_ON(atomic_read(&mm->mm_users) <= 0); - if (IS_ENABLED(CONFIG_LOCKDEP)) { - fs_reclaim_acquire(GFP_KERNEL); - lock_map_acquire(&__mmu_notifier_invalidate_range_start_map); - lock_map_release(&__mmu_notifier_invalidate_range_start_map); - fs_reclaim_release(GFP_KERNEL); - } - if (!mm->notifier_subscriptions) { /* * kmalloc cannot be called under mm_take_all_locks(), but we diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 23f5066bd4a5..ff0f9a84b8de 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -57,6 +57,7 @@ #include #include #include +#include #include #include #include @@ -4264,10 +4265,8 @@ should_compact_retry(struct alloc_context *ac, unsigned int order, int alloc_fla static struct lockdep_map __fs_reclaim_map = STATIC_LOCKDEP_MAP_INIT("fs_reclaim", &__fs_reclaim_map); -static bool __need_fs_reclaim(gfp_t gfp_mask) +static bool __need_reclaim(gfp_t gfp_mask) { - gfp_mask = current_gfp_context(gfp_mask); - /* no reclaim without waiting on it */ if (!(gfp_mask & __GFP_DIRECT_RECLAIM)) return false; @@ -4276,10 +4275,6 @@ static bool __need_fs_reclaim(gfp_t gfp_mask) if (current->flags & PF_MEMALLOC) return false; - /* We're only interested __GFP_FS allocations for now */ - if (!(gfp_mask & __GFP_FS)) - return false; - if (gfp_mask & __GFP_NOLOCKDEP) return false; @@ -4298,15 +4293,29 @@ void __fs_reclaim_release(void) void fs_reclaim_acquire(gfp_t gfp_mask) { - if (__need_fs_reclaim(gfp_mask)) - __fs_reclaim_acquire(); + gfp_mask = current_gfp_context(gfp_mask); + + if (__need_reclaim(gfp_mask)) { + if (gfp_mask & __GFP_FS) + __fs_reclaim_acquire(); + +#ifdef CONFIG_MMU_NOTIFIER + lock_map_acquire(&__mmu_notifier_invalidate_range_start_map); + lock_map_release(&__mmu_notifier_invalidate_range_start_map); +#endif + + } } EXPORT_SYMBOL_GPL(fs_reclaim_acquire); void fs_reclaim_release(gfp_t gfp_mask) { - if (__need_fs_reclaim(gfp_mask)) - __fs_reclaim_release(); + gfp_mask = current_gfp_context(gfp_mask); + + if (__need_reclaim(gfp_mask)) { + if (gfp_mask & __GFP_FS) + __fs_reclaim_release(); + } } EXPORT_SYMBOL_GPL(fs_reclaim_release); #endif From patchwork Fri Nov 20 09:54:43 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Daniel Vetter X-Patchwork-Id: 11919981 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=-18.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, 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 B3B87C8300E for ; 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Fri, 20 Nov 2020 01:56:13 -0800 (PST) Received: from phenom.ffwll.local ([2a02:168:57f4:0:efd0:b9e5:5ae6:c2fa]) by smtp.gmail.com with ESMTPSA id t9sm4500208wrr.49.2020.11.20.01.56.11 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 20 Nov 2020 01:56:12 -0800 (PST) From: Daniel Vetter To: DRI Development Cc: Intel Graphics Development , linux-mm@kvack.org, linux-xfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, LKML , Daniel Vetter , Vlastimil Babka , "Paul E . McKenney" , Christoph Lameter , Pekka Enberg , David Rientjes , Joonsoo Kim , Andrew Morton , Peter Zijlstra , Ingo Molnar , Mathieu Desnoyers , Sebastian Andrzej Siewior , Michel Lespinasse , Waiman Long , Thomas Gleixner , Randy Dunlap , Dave Chinner , Qian Cai , "Matthew Wilcox (Oracle)" , Daniel Vetter Subject: [PATCH 2/3] mm: Extract might_alloc() debug check Date: Fri, 20 Nov 2020 10:54:43 +0100 Message-Id: <20201120095445.1195585-3-daniel.vetter@ffwll.ch> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201120095445.1195585-1-daniel.vetter@ffwll.ch> References: <20201120095445.1195585-1-daniel.vetter@ffwll.ch> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org Extracted from slab.h, which seems to have the most complete version including the correct might_sleep() check. Roll it out to slob.c. Motivated by a discussion with Paul about possibly changing call_rcu behaviour to allocate memory, but only roughly every 500th call. There are a lot fewer places in the kernel that care about whether allocating memory is allowed or not (due to deadlocks with reclaim code) than places that care whether sleeping is allowed. But debugging these also tends to be a lot harder, so nice descriptive checks could come in handy. I might have some use eventually for annotations in drivers/gpu. Note that unlike fs_reclaim_acquire/release gfpflags_allow_blocking does not consult the PF_MEMALLOC flags. But there is no flag equivalent for GFP_NOWAIT, hence this check can't go wrong due to memalloc_no*_save/restore contexts. Willy is working on a patch series which might change this: https://lore.kernel.org/linux-mm/20200625113122.7540-7-willy@infradead.org/ I think best would be if that updates gfpflags_allow_blocking(), since there's a ton of callers all over the place for that already. Acked-by: Vlastimil Babka Acked-by: Paul E. McKenney Cc: Paul E. McKenney Cc: Christoph Lameter Cc: Pekka Enberg Cc: David Rientjes Cc: Joonsoo Kim Cc: Andrew Morton Cc: Peter Zijlstra Cc: Ingo Molnar Cc: Vlastimil Babka Cc: Mathieu Desnoyers Cc: Sebastian Andrzej Siewior Cc: Michel Lespinasse Cc: Daniel Vetter Cc: Waiman Long Cc: Thomas Gleixner Cc: Randy Dunlap Cc: linux-mm@kvack.org Cc: linux-fsdevel@vger.kernel.org Cc: Dave Chinner Cc: Qian Cai Cc: linux-xfs@vger.kernel.org Cc: "Matthew Wilcox (Oracle)" Signed-off-by: Daniel Vetter Reviewed-by: Jason Gunthorpe --- include/linux/sched/mm.h | 16 ++++++++++++++++ mm/slab.h | 5 +---- mm/slob.c | 6 ++---- 3 files changed, 19 insertions(+), 8 deletions(-) diff --git a/include/linux/sched/mm.h b/include/linux/sched/mm.h index d5ece7a9a403..f94405d43fd1 100644 --- a/include/linux/sched/mm.h +++ b/include/linux/sched/mm.h @@ -180,6 +180,22 @@ static inline void fs_reclaim_acquire(gfp_t gfp_mask) { } static inline void fs_reclaim_release(gfp_t gfp_mask) { } #endif +/** + * might_alloc - Marks possible allocation sites + * @gfp_mask: gfp_t flags that would be use to allocate + * + * Similar to might_sleep() and other annotations this can be used in functions + * that might allocate, but often dont. Compiles to nothing without + * CONFIG_LOCKDEP. Includes a conditional might_sleep() if @gfp allows blocking. + */ +static inline void might_alloc(gfp_t gfp_mask) +{ + fs_reclaim_acquire(gfp_mask); + fs_reclaim_release(gfp_mask); + + might_sleep_if(gfpflags_allow_blocking(gfp_mask)); +} + /** * memalloc_noio_save - Marks implicit GFP_NOIO allocation scope. * diff --git a/mm/slab.h b/mm/slab.h index 6d7c6a5056ba..37b981247e5d 100644 --- a/mm/slab.h +++ b/mm/slab.h @@ -500,10 +500,7 @@ static inline struct kmem_cache *slab_pre_alloc_hook(struct kmem_cache *s, { flags &= gfp_allowed_mask; - fs_reclaim_acquire(flags); - fs_reclaim_release(flags); - - might_sleep_if(gfpflags_allow_blocking(flags)); + might_alloc(flags); if (should_failslab(s, flags)) return NULL; diff --git a/mm/slob.c b/mm/slob.c index 7cc9805c8091..8d4bfa46247f 100644 --- a/mm/slob.c +++ b/mm/slob.c @@ -474,8 +474,7 @@ __do_kmalloc_node(size_t size, gfp_t gfp, int node, unsigned long caller) gfp &= gfp_allowed_mask; - fs_reclaim_acquire(gfp); - fs_reclaim_release(gfp); + might_alloc(gfp); if (size < PAGE_SIZE - minalign) { int align = minalign; @@ -597,8 +596,7 @@ static void *slob_alloc_node(struct kmem_cache *c, gfp_t flags, int node) flags &= gfp_allowed_mask; - fs_reclaim_acquire(flags); - fs_reclaim_release(flags); + might_alloc(flags); if (c->size < PAGE_SIZE) { b = slob_alloc(c->size, flags, c->align, node, 0); From patchwork Fri Nov 20 09:54:44 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Daniel Vetter X-Patchwork-Id: 11919975 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=-18.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, 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 E8E8DC64E75 for ; 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Fri, 20 Nov 2020 01:56:14 -0800 (PST) Received: from phenom.ffwll.local ([2a02:168:57f4:0:efd0:b9e5:5ae6:c2fa]) by smtp.gmail.com with ESMTPSA id t9sm4500208wrr.49.2020.11.20.01.56.13 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 20 Nov 2020 01:56:13 -0800 (PST) From: Daniel Vetter To: DRI Development Cc: Intel Graphics Development , linux-mm@kvack.org, linux-xfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, LKML , Daniel Vetter , Dave Chinner , Qian Cai , =?utf-8?q?Thomas?= =?utf-8?q?_Hellstr=C3=B6m?= , Andrew Morton , Jason Gunthorpe , linux-rdma@vger.kernel.org, Maarten Lankhorst , =?utf-8?q?Christian_?= =?utf-8?q?K=C3=B6nig?= , "Matthew Wilcox (Oracle)" , Daniel Vetter , Peter Zijlstra , Ingo Molnar , Will Deacon Subject: [PATCH 3/3] locking/selftests: Add testcases for fs_reclaim Date: Fri, 20 Nov 2020 10:54:44 +0100 Message-Id: <20201120095445.1195585-4-daniel.vetter@ffwll.ch> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201120095445.1195585-1-daniel.vetter@ffwll.ch> References: <20201120095445.1195585-1-daniel.vetter@ffwll.ch> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org Since I butchered this I figured better to make sure we have testcases for this now. Since we only have a locking context for __GFP_FS that's the only thing we're testing right now. Cc: linux-fsdevel@vger.kernel.org Cc: Dave Chinner Cc: Qian Cai Cc: linux-xfs@vger.kernel.org Cc: Thomas Hellström (Intel) Cc: Andrew Morton Cc: Jason Gunthorpe Cc: linux-mm@kvack.org Cc: linux-rdma@vger.kernel.org Cc: Maarten Lankhorst Cc: Christian König Cc: "Matthew Wilcox (Oracle)" Signed-off-by: Daniel Vetter Cc: Peter Zijlstra Cc: Ingo Molnar Cc: Will Deacon Cc: linux-kernel@vger.kernel.org Acked-by: Peter Zijlstra (Intel) --- lib/locking-selftest.c | 47 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 47 insertions(+) diff --git a/lib/locking-selftest.c b/lib/locking-selftest.c index a899b3f0e2e5..ad47c3358e30 100644 --- a/lib/locking-selftest.c +++ b/lib/locking-selftest.c @@ -15,6 +15,7 @@ #include #include #include +#include #include #include #include @@ -2357,6 +2358,50 @@ static void queued_read_lock_tests(void) pr_cont("\n"); } +static void fs_reclaim_correct_nesting(void) +{ + fs_reclaim_acquire(GFP_KERNEL); + might_alloc(GFP_NOFS); + fs_reclaim_release(GFP_KERNEL); +} + +static void fs_reclaim_wrong_nesting(void) +{ + fs_reclaim_acquire(GFP_KERNEL); + might_alloc(GFP_KERNEL); + fs_reclaim_release(GFP_KERNEL); +} + +static void fs_reclaim_protected_nesting(void) +{ + unsigned int flags; + + fs_reclaim_acquire(GFP_KERNEL); + flags = memalloc_nofs_save(); + might_alloc(GFP_KERNEL); + memalloc_nofs_restore(flags); + fs_reclaim_release(GFP_KERNEL); +} + +static void fs_reclaim_tests(void) +{ + printk(" --------------------\n"); + printk(" | fs_reclaim tests |\n"); + printk(" --------------------\n"); + + print_testname("correct nesting"); + dotest(fs_reclaim_correct_nesting, SUCCESS, 0); + pr_cont("\n"); + + print_testname("wrong nesting"); + dotest(fs_reclaim_wrong_nesting, FAILURE, 0); + pr_cont("\n"); + + print_testname("protected nesting"); + dotest(fs_reclaim_protected_nesting, SUCCESS, 0); + pr_cont("\n"); +} + void locking_selftest(void) { /* @@ -2478,6 +2523,8 @@ void locking_selftest(void) if (IS_ENABLED(CONFIG_QUEUED_RWLOCKS)) queued_read_lock_tests(); + fs_reclaim_tests(); + if (unexpected_testcase_failures) { printk("-----------------------------------------------------------------\n"); debug_locks = 0;