From nobody Fri Dec 19 17:19:25 2025 Received: from invmail4.hynix.com (exvmail4.hynix.com [166.125.252.92]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 093762701C8; Mon, 19 May 2025 09:18:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=166.125.252.92 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1747646341; cv=none; b=sYFyhOJRMZqGbTqYYj0JgvCbwPUpLeXYbvuz31V3M+R3BuMsEy6WjmYyV+umBHnwqC75tBLKgZwRKhgYhKFf09c0jkQxq8H/vorydn8STKtDmt6QvHErJWI/9stc5q5o6x6a83IEUusStH3Q9Kw43xJiOfsI8tTEg140l77YWqo= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1747646341; c=relaxed/simple; bh=eqhIu4Ytfemwyxgng3iHH4sQt4GfdE3Wth8zaCAgCgk=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References; b=f3rnHNbmzAtyTv7fivOFuDTJH8PpRHpn9OZRJsD9WZ3uM4e16OB3BRzZHMiRwCMEhSgUxp1yGeO42ypLHC/bLEKkPNQ9kKxWuz4PWbzCZ4no6yttJvICk29oG80D1xDYHV1h9i+CyRFPmlzYv7/n61uwrTL1qHIdY0zkUUdEdXM= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=sk.com; spf=pass smtp.mailfrom=sk.com; arc=none smtp.client-ip=166.125.252.92 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=sk.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=sk.com X-AuditID: a67dfc5b-681ff7000002311f-5e-682af76f6d09 From: Byungchul Park To: linux-kernel@vger.kernel.org Cc: kernel_team@skhynix.com, torvalds@linux-foundation.org, damien.lemoal@opensource.wdc.com, linux-ide@vger.kernel.org, adilger.kernel@dilger.ca, linux-ext4@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, will@kernel.org, tglx@linutronix.de, rostedt@goodmis.org, joel@joelfernandes.org, sashal@kernel.org, daniel.vetter@ffwll.ch, duyuyang@gmail.com, johannes.berg@intel.com, tj@kernel.org, tytso@mit.edu, willy@infradead.org, david@fromorbit.com, amir73il@gmail.com, gregkh@linuxfoundation.org, kernel-team@lge.com, linux-mm@kvack.org, akpm@linux-foundation.org, mhocko@kernel.org, minchan@kernel.org, hannes@cmpxchg.org, vdavydov.dev@gmail.com, sj@kernel.org, jglisse@redhat.com, dennis@kernel.org, cl@linux.com, penberg@kernel.org, rientjes@google.com, vbabka@suse.cz, ngupta@vflare.org, linux-block@vger.kernel.org, josef@toxicpanda.com, linux-fsdevel@vger.kernel.org, jack@suse.cz, jlayton@kernel.org, dan.j.williams@intel.com, hch@infradead.org, djwong@kernel.org, dri-devel@lists.freedesktop.org, rodrigosiqueiramelo@gmail.com, melissa.srw@gmail.com, hamohammed.sa@gmail.com, harry.yoo@oracle.com, chris.p.wilson@intel.com, gwan-gyeong.mun@intel.com, max.byungchul.park@gmail.com, boqun.feng@gmail.com, longman@redhat.com, yskelg@gmail.com, yunseong.kim@ericsson.com, yeoreum.yun@arm.com, netdev@vger.kernel.org, matthew.brost@intel.com, her0gyugyu@gmail.com Subject: [PATCH v16 25/42] dept: track PG_locked with dept Date: Mon, 19 May 2025 18:18:09 +0900 Message-Id: <20250519091826.19752-26-byungchul@sk.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20250519091826.19752-1-byungchul@sk.com> References: <20250519091826.19752-1-byungchul@sk.com> X-Brightmail-Tracker: H4sIAAAAAAAAAzWSa0yTZxTHfd47leprR9wrLrrVuDlUFIJ4YtQtJmaPLrol24dlftAqb2y1 XFIUxUQtcgmDQeqlVLFiC6MyWqC2xKCjBGFUwBsqtsCgm3jZkJuptgiCrmD8cvLL/5/zO18O R8pa6UhOlXRA1CQp1HJGQkmGw80rk8eilKufemMh8CqXAmONjYGOaisCW20GAQMt34A3OITg ze27JBj0HQjMj/pIqHX7ELgqTjDw4Mkc6AyMMtCmz2cgs6yGgXuDkwT0Fp0iwOrYBn9bnlFw U1dKgGGAgfOGTCI0/iNg3FLJgkW7FPorilmYfBQDbT4PDa6e5XCupJeBelcbBe66fgIeXDMy 4LO9o+Gmu5WCYOFC6DhZQEPVSCkDg0ELCZbAKAv3G00EuE3zwZ4VEua8fEvDjYJGAnJ+u0xA Z/cfCBpy/yHAYfMw0BwYIsDp0JMwcakFQX/hMAvZv46zcD6jEEF+dhEFWb1r4M3r0OULr2Ig 46KdgqopD/p6A7aV2BBuHholcZbzEJ4IPGSwK2iicHupgK8W97E4q6GHxSbHQeysiMJl9QME NvsDNHZU/sJgh/8Ui/OGOwk8cucO+/0nP0vWJ4hqVZqoWbVxl0SZO2WnU1p3Hb7fP0Jpkfa7 PBTGCXycMNB+lv3AZTdezDDDfyF0dY2T0xzBfyo4C57ReUjCkbxntuC90I2mi4/4dYJ7TEtM M8UvFVo8ZTO5lI8XBnuL0HvpYsFqb5wRhYXynvzmmVzGrxE6rSXUtFTgDWFC362n1PuFBcL1 ii5Kh6QmNKsSyVRJaYkKlTouWpmepDocvSc50YFC/2U5OrmjDvk7fmhCPIfk4VK760uljFak paYnNiGBI+UR0krnMqVMmqBIPyJqkndqDqrF1Ca0kKPkH0tjg4cSZPxexQFxvyimiJoPLcGF RWqRMv6zl4bN11ui8x47Pk83Z24pNUSW7710zHiuTle+qJosVv+0ZEVaOYvO3HV7rUZdyfzw Iz7SQ/nNJ/XGTc+9l7trt85r3z5RNfeKd/W3urHj3O7YiW27F8dn/5mjkqwt/H3ljziY0kPr j/v/2jp1NqLq39NxmmjN9iW+r07vGNv3Qk6lKhUxUaQmVfE/ra0sz1sDAAA= X-Brightmail-Tracker: H4sIAAAAAAAAAzWSfUzMcRzHfX+P13H2cxq/iWlnqExkZR8P87jlJ48bZvOPTn78btVld0kZ cymkujxsFaVcxcndxXWnrXC0TqdjSOV6WIVjTStldEcP4sr889lrr/f2fv/zEeFSAzlHpFAm 8iqlPE5GiQnxzjVpSxN+hgjL7U1zwTOUQcCN+yYKGu8ZEZgepGLQW78FWr39CEZfvcEhP7cR QcnHLhweOLoR2MrPUtD8eTq0eAYpcOZmUZBWdp+Ct31jGHTmXcXAaNkB7/U9BLy8XIpBfi8F hflpmO98wWBYb6BBr1kI7vICGsY+hoGz20WCvchJgq1jCVwv7qTgsc1JgKPajUHzwxsUdJv+ kPDS0UCANycAGq9oSagYKKWgz6vHQe8ZpKGpVoeBQzcLzOm+1vM/xkl4rq3F4PytSgxa2h8h eJLxAQOLyUWB3dOPgdWSi8PInXoE7pyvNJzLHqahMDUHQda5PALSOyNg9JdvuWgoDFJvmgmo +O1CG9ZxpmIT4uz9gziXbj3BjXjeUZzNqyO4F6UsV1PQRXPpTzpoTmc5zlnLQ7iyx70YV/Ld Q3IWw0WKs3y/SnOZX1swbuD1a3r3vAPitYf5OEUSr1q2LlosZPw2k8caopOb3AOEBml2ZSI/ EcuEs2XPv9ETTDGL2ba2YXyC/ZlA1qrtITORWIQzrqlsa1E7mghmMqtZx08NNsEEs5Ctd5VN egmzku3rzEP/SuezRnPtZJGfz3dk2Se9lIlgW4zFxGUk1qEpBuSvUCbFyxVxEaHqWCFFqUgO jUmItyDfB+lPj12pRkPNW+oQI0KyaRKzLViQkvIkdUp8HWJFuMxfYrAGCVLJYXnKSV6VcFB1 PI5X16EAESGbLYnaz0dLmaPyRD6W54/xqv8pJvKbo0F3nSujSgvnx4bbosJ7cjpqPux1r254 FLlnVd72bxJlyubI9cLGS9JnimBvW8TW7HtFrk8a4Vp1zbXAqhkzTNqqI2zyoikLNgZqRzzj 43Vd/TFrbey7bfSzvWTYvqdLrWOHTjQKlZtyE0tODQeciQw9WWG7XWnUXUgaDcpiVhy8dDRb RqgFeVgIrlLL/wK/9ilkPQMAAA== X-CFilter-Loop: Reflected Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Makes dept able to track PG_locked waits and events, which will be useful in practice. See the following link that shows dept worked with PG_locked and detected real issues in practice: https://lore.kernel.org/lkml/1674268856-31807-1-git-send-email-byungchul= .park@lge.com/ Signed-off-by: Byungchul Park --- include/linux/mm_types.h | 2 + include/linux/page-flags.h | 125 +++++++++++++++++++++++++++++++++---- include/linux/pagemap.h | 16 ++++- mm/filemap.c | 26 ++++++++ mm/mm_init.c | 2 + 5 files changed, 158 insertions(+), 13 deletions(-) diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h index 56d07edd01f9..7e9d63cef28a 100644 --- a/include/linux/mm_types.h +++ b/include/linux/mm_types.h @@ -20,6 +20,7 @@ #include #include #include +#include =20 #include =20 @@ -224,6 +225,7 @@ struct page { struct page *kmsan_shadow; struct page *kmsan_origin; #endif + struct dept_ext_wgen pg_locked_wgen; } _struct_page_alignment; =20 /* diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h index e6a21b62dcce..73cb8a1ad4f3 100644 --- a/include/linux/page-flags.h +++ b/include/linux/page-flags.h @@ -194,6 +194,61 @@ enum pageflags { =20 #ifndef __GENERATING_BOUNDS_H =20 +#ifdef CONFIG_DEPT +#include +#include + +extern struct dept_map pg_locked_map; + +/* + * Place the following annotations in its suitable point in code: + * + * Annotate dept_page_set_bit() around firstly set_bit*() + * Annotate dept_page_clear_bit() around clear_bit*() + * Annotate dept_page_wait_on_bit() around wait_on_bit*() + */ + +static inline void dept_page_set_bit(struct page *p, int bit_nr) +{ + if (bit_nr =3D=3D PG_locked) + dept_request_event(&pg_locked_map, &p->pg_locked_wgen); +} + +static inline void dept_page_clear_bit(struct page *p, int bit_nr) +{ + if (bit_nr =3D=3D PG_locked) + dept_event(&pg_locked_map, 1UL, _RET_IP_, __func__, &p->pg_locked_wgen); +} + +static inline void dept_page_wait_on_bit(struct page *p, int bit_nr) +{ + if (bit_nr =3D=3D PG_locked) + dept_wait(&pg_locked_map, 1UL, _RET_IP_, __func__, 0, -1L); +} + +static inline void dept_folio_set_bit(struct folio *f, int bit_nr) +{ + dept_page_set_bit(&f->page, bit_nr); +} + +static inline void dept_folio_clear_bit(struct folio *f, int bit_nr) +{ + dept_page_clear_bit(&f->page, bit_nr); +} + +static inline void dept_folio_wait_on_bit(struct folio *f, int bit_nr) +{ + dept_page_wait_on_bit(&f->page, bit_nr); +} +#else +#define dept_page_set_bit(p, bit_nr) do { } while (0) +#define dept_page_clear_bit(p, bit_nr) do { } while (0) +#define dept_page_wait_on_bit(p, bit_nr) do { } while (0) +#define dept_folio_set_bit(f, bit_nr) do { } while (0) +#define dept_folio_clear_bit(f, bit_nr) do { } while (0) +#define dept_folio_wait_on_bit(f, bit_nr) do { } while (0) +#endif + #ifdef CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP DECLARE_STATIC_KEY_FALSE(hugetlb_optimize_vmemmap_key); =20 @@ -415,27 +470,51 @@ static __always_inline bool folio_test_##name(const s= truct folio *folio) \ =20 #define FOLIO_SET_FLAG(name, page) \ static __always_inline void folio_set_##name(struct folio *folio) \ -{ set_bit(PG_##name, folio_flags(folio, page)); } +{ \ + set_bit(PG_##name, folio_flags(folio, page)); \ + dept_folio_set_bit(folio, PG_##name); \ +} =20 #define FOLIO_CLEAR_FLAG(name, page) \ static __always_inline void folio_clear_##name(struct folio *folio) \ -{ clear_bit(PG_##name, folio_flags(folio, page)); } +{ \ + clear_bit(PG_##name, folio_flags(folio, page)); \ + dept_folio_clear_bit(folio, PG_##name); \ +} =20 #define __FOLIO_SET_FLAG(name, page) \ static __always_inline void __folio_set_##name(struct folio *folio) \ -{ __set_bit(PG_##name, folio_flags(folio, page)); } +{ \ + __set_bit(PG_##name, folio_flags(folio, page)); \ + dept_folio_set_bit(folio, PG_##name); \ +} =20 #define __FOLIO_CLEAR_FLAG(name, page) \ static __always_inline void __folio_clear_##name(struct folio *folio) \ -{ __clear_bit(PG_##name, folio_flags(folio, page)); } +{ \ + __clear_bit(PG_##name, folio_flags(folio, page)); \ + dept_folio_clear_bit(folio, PG_##name); \ +} =20 #define FOLIO_TEST_SET_FLAG(name, page) \ static __always_inline bool folio_test_set_##name(struct folio *folio) \ -{ return test_and_set_bit(PG_##name, folio_flags(folio, page)); } +{ \ + bool __ret =3D test_and_set_bit(PG_##name, folio_flags(folio, page)); \ + \ + if (!__ret) \ + dept_folio_set_bit(folio, PG_##name); \ + return __ret; \ +} =20 #define FOLIO_TEST_CLEAR_FLAG(name, page) \ static __always_inline bool folio_test_clear_##name(struct folio *folio) \ -{ return test_and_clear_bit(PG_##name, folio_flags(folio, page)); } +{ \ + bool __ret =3D test_and_clear_bit(PG_##name, folio_flags(folio, page)); \ + \ + if (__ret) \ + dept_folio_clear_bit(folio, PG_##name); \ + return __ret; \ +} =20 #define FOLIO_FLAG(name, page) \ FOLIO_TEST_FLAG(name, page) \ @@ -450,32 +529,54 @@ static __always_inline int Page##uname(const struct p= age *page) \ #define SETPAGEFLAG(uname, lname, policy) \ FOLIO_SET_FLAG(lname, FOLIO_##policy) \ static __always_inline void SetPage##uname(struct page *page) \ -{ set_bit(PG_##lname, &policy(page, 1)->flags); } +{ \ + set_bit(PG_##lname, &policy(page, 1)->flags); \ + dept_page_set_bit(page, PG_##lname); \ +} =20 #define CLEARPAGEFLAG(uname, lname, policy) \ FOLIO_CLEAR_FLAG(lname, FOLIO_##policy) \ static __always_inline void ClearPage##uname(struct page *page) \ -{ clear_bit(PG_##lname, &policy(page, 1)->flags); } +{ \ + clear_bit(PG_##lname, &policy(page, 1)->flags); \ + dept_page_clear_bit(page, PG_##lname); \ +} =20 #define __SETPAGEFLAG(uname, lname, policy) \ __FOLIO_SET_FLAG(lname, FOLIO_##policy) \ static __always_inline void __SetPage##uname(struct page *page) \ -{ __set_bit(PG_##lname, &policy(page, 1)->flags); } +{ \ + __set_bit(PG_##lname, &policy(page, 1)->flags); \ + dept_page_set_bit(page, PG_##lname); \ +} =20 #define __CLEARPAGEFLAG(uname, lname, policy) \ __FOLIO_CLEAR_FLAG(lname, FOLIO_##policy) \ static __always_inline void __ClearPage##uname(struct page *page) \ -{ __clear_bit(PG_##lname, &policy(page, 1)->flags); } +{ \ + __clear_bit(PG_##lname, &policy(page, 1)->flags); \ + dept_page_clear_bit(page, PG_##lname); \ +} =20 #define TESTSETFLAG(uname, lname, policy) \ FOLIO_TEST_SET_FLAG(lname, FOLIO_##policy) \ static __always_inline int TestSetPage##uname(struct page *page) \ -{ return test_and_set_bit(PG_##lname, &policy(page, 1)->flags); } +{ \ + bool ret =3D test_and_set_bit(PG_##lname, &policy(page, 1)->flags);\ + if (!ret) \ + dept_page_set_bit(page, PG_##lname); \ + return ret; \ +} =20 #define TESTCLEARFLAG(uname, lname, policy) \ FOLIO_TEST_CLEAR_FLAG(lname, FOLIO_##policy) \ static __always_inline int TestClearPage##uname(struct page *page) \ -{ return test_and_clear_bit(PG_##lname, &policy(page, 1)->flags); } +{ \ + bool ret =3D test_and_clear_bit(PG_##lname, &policy(page, 1)->flags);\ + if (ret) \ + dept_page_clear_bit(page, PG_##lname); \ + return ret; \ +} =20 #define PAGEFLAG(uname, lname, policy) \ TESTPAGEFLAG(uname, lname, policy) \ diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h index 26baa78f1ca7..c4c9742c7a29 100644 --- a/include/linux/pagemap.h +++ b/include/linux/pagemap.h @@ -1097,7 +1097,12 @@ void folio_unlock(struct folio *folio); */ static inline bool folio_trylock(struct folio *folio) { - return likely(!test_and_set_bit_lock(PG_locked, folio_flags(folio, 0))); + bool ret =3D !test_and_set_bit_lock(PG_locked, folio_flags(folio, 0)); + + if (ret) + dept_page_set_bit(&folio->page, PG_locked); + + return likely(ret); } =20 /* @@ -1133,6 +1138,15 @@ static inline bool trylock_page(struct page *page) static inline void folio_lock(struct folio *folio) { might_sleep(); + /* + * dept_page_wait_on_bit() will be called if __folio_lock() goes + * through a real wait path. However, for better job to detect + * *potential* deadlocks, let's assume that folio_lock() always + * goes through wait so that dept can take into account all the + * potential cases. + */ + dept_page_wait_on_bit(&folio->page, PG_locked); + if (!folio_trylock(folio)) __folio_lock(folio); } diff --git a/mm/filemap.c b/mm/filemap.c index 7b90cbeb4a1a..cab03b41add2 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -48,6 +48,7 @@ #include #include #include +#include #include #include #include "internal.h" @@ -1145,6 +1146,7 @@ static int wake_page_function(wait_queue_entry_t *wai= t, unsigned mode, int sync, if (flags & WQ_FLAG_CUSTOM) { if (test_and_set_bit(key->bit_nr, &key->folio->flags)) return -1; + dept_page_set_bit(&key->folio->page, key->bit_nr); flags |=3D WQ_FLAG_DONE; } } @@ -1228,6 +1230,7 @@ static inline bool folio_trylock_flag(struct folio *f= olio, int bit_nr, if (wait->flags & WQ_FLAG_EXCLUSIVE) { if (test_and_set_bit(bit_nr, &folio->flags)) return false; + dept_page_set_bit(&folio->page, bit_nr); } else if (test_bit(bit_nr, &folio->flags)) return false; =20 @@ -1235,6 +1238,9 @@ static inline bool folio_trylock_flag(struct folio *f= olio, int bit_nr, return true; } =20 +struct dept_map __maybe_unused pg_locked_map =3D DEPT_MAP_INITIALIZER(pg_l= ocked_map, NULL); +EXPORT_SYMBOL(pg_locked_map); + static inline int folio_wait_bit_common(struct folio *folio, int bit_nr, int state, enum behavior behavior) { @@ -1246,6 +1252,8 @@ static inline int folio_wait_bit_common(struct folio = *folio, int bit_nr, unsigned long pflags; bool in_thrashing; =20 + dept_page_wait_on_bit(&folio->page, bit_nr); + if (bit_nr =3D=3D PG_locked && !folio_test_uptodate(folio) && folio_test_workingset(folio)) { delayacct_thrashing_start(&in_thrashing); @@ -1339,6 +1347,23 @@ static inline int folio_wait_bit_common(struct folio= *folio, int bit_nr, break; } =20 + /* + * dept_page_set_bit() might have been called already in + * folio_trylock_flag(), wake_page_function() or somewhere. + * However, call it again to reset the wgen of dept to ensure + * dept_page_wait_on_bit() is called prior to + * dept_page_set_bit(). + * + * Remind dept considers all the waits between + * dept_page_set_bit() and dept_page_clear_bit() as potential + * event disturbers. Ensure the correct sequence so that dept + * can make correct decisions: + * + * wait -> acquire(set bit) -> release(clear bit) + */ + if (wait->flags & WQ_FLAG_DONE) + dept_page_set_bit(&folio->page, bit_nr); + /* * If a signal happened, this 'finish_wait()' may remove the last * waiter from the wait-queues, but the folio waiters bit will remain @@ -1496,6 +1521,7 @@ void folio_unlock(struct folio *folio) BUILD_BUG_ON(PG_waiters !=3D 7); BUILD_BUG_ON(PG_locked > 7); VM_BUG_ON_FOLIO(!folio_test_locked(folio), folio); + dept_page_clear_bit(&folio->page, PG_locked); if (folio_xor_flags_has_waiters(folio, 1 << PG_locked)) folio_wake_bit(folio, PG_locked); } diff --git a/mm/mm_init.c b/mm/mm_init.c index 327764ca0ee4..39cf0bc355ba 100644 --- a/mm/mm_init.c +++ b/mm/mm_init.c @@ -31,6 +31,7 @@ #include #include #include +#include #include "internal.h" #include "slab.h" #include "shuffle.h" @@ -586,6 +587,7 @@ void __meminit __init_single_page(struct page *page, un= signed long pfn, atomic_set(&page->_mapcount, -1); page_cpupid_reset_last(page); page_kasan_tag_reset(page); + dept_ext_wgen_init(&page->pg_locked_wgen); =20 INIT_LIST_HEAD(&page->lru); #ifdef WANT_PAGE_VIRTUAL --=20 2.17.1