From nobody Wed Nov 27 14:33:18 2024 Received: from mail-pl1-f202.google.com (mail-pl1-f202.google.com [209.85.214.202]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3D8FB1E4938 for ; Wed, 9 Oct 2024 23:54:04 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.202 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728518046; cv=none; b=qE4wptaAZC8ht9OcJNrfB3I66/jW3181jL1RkTPXD1fWGY5yXXulJjoxHjC8faK5Uxwy3aJ6EI5dw8ZGDcaVDIahmWbvxuEV+IKiitWGfWCRczqHwda2Eudbcp7gcXLfvfULLGp7WK71AAKR0I9mXb+W/2Ub7RrzYshm6MoIltY= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728518046; c=relaxed/simple; bh=KWAj6wk+ROTEAyXmpszVgA19aen+LhUt2NwX+DVMPlQ=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=Amy2SylL6achMXteFga3rePYWP2kNdw4oAl7AilE3do8vlBkNZ9yLN0+HFzvDB7FlVYrk2GDTsDjSxhTF8UHAW7+ssCQ1UM+25jkeGNwlKCssjiVYwFZ1tUeLgEE/DjQoqktfBLY4t52xTkVBDhOg7hmMLUGkjesCbD2GvKdOpY= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--jstultz.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=tgKiU3us; arc=none smtp.client-ip=209.85.214.202 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--jstultz.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="tgKiU3us" Received: by mail-pl1-f202.google.com with SMTP id d9443c01a7336-20b921fa133so4623825ad.1 for ; Wed, 09 Oct 2024 16:54:04 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1728518043; x=1729122843; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=k5GN2mZa/JLSWB1RVVgZGxEJN+CSHE1NkkXng6IH6v4=; b=tgKiU3usU7Z9dkrCzSpFMhhCnGoZNgtCojJlX4JAHcjworm0o+nkKhZKfpujeFHcm8 sR55YZOhrLPvgOwt5xcaPRU01zetlTaa8ntqC+cOLHSbGMH+AglGszZiZ+iVlz3fOLxc EC36Gfv8n2fZUWKzA/Et+K7lo3H07pqM9gO35C/Lmtb24JQRKPz9FACf1hZ0VC8D7ELz XNLrGsBVkCyuwKGuVqzTAamr+R+K4wluTVctpa++vLrQOaItYCfzpN0TJxYw+7d+KPCa PKp8OgwOnDGz7208hNLdTBkpUWSTdIefgB857qs9OLI4Je3fOUtqKVARjn35V9lgXw+9 DiFQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1728518043; x=1729122843; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=k5GN2mZa/JLSWB1RVVgZGxEJN+CSHE1NkkXng6IH6v4=; b=OISuiSrffQwOCUe8aA9CEOob0r3CZ/dBsupeA7PqL6H/sSrxifMgBfdUMUnE6NsYp8 FP3h7dSn68fwvz5bNDPrmd5obDrlQSFpSRxish70IgzA/+qX1120DNk2AVo4cZTUMcx7 NgWAnAWCjcKd7alRJdE73dUTr22PGUXChg9NS3eep7jvLntr/HpYFgTiu6IAmyrYTVRp G6baKosbCa/I5XdmmOm70pJpfTk5tiB3yWC9d1CAj0mkuWxxoXK8ESi7bBiS1XGrgrfc oLuq5E2J0FooWUMpliW86QqSGVThMaGacehsdnyU2Q2q8Sy2K1RIGqQGzCFYAQxN6pfa zf6g== X-Gm-Message-State: AOJu0YzEnsLNFx4tmPSKNOpaIWRrbeVOh0giV2FPC2VZBCGMoogLiWHo 6P8qjQ0CbMdn8w4WKyha37M4J0IvRQGWZIk3LXZQG6JbahB4rWA+fXw34m5VMyWJqLj6GUjY6GF vcIlkkueBOPTL0NmwhR7kUvEQuz0xOOOg2QOGFOSAfUsJOBjJQs9ToLO1Wr/eDS7q9lOdwPX8Ps QZRFU53oalEfFJAAzGjZpaVNO3Sc+B+f15l0m3dF4ArA1j X-Google-Smtp-Source: AGHT+IENaf10vSUFiRweEiS+T4vUt4SKW3bM3mQJWUgWonZu9nTbAXlX/VLV/yd61ZlC6qLeJ4lBN6J9aqFs X-Received: from jstultz-noogler2.c.googlers.com ([fda3:e722:ac3:cc00:24:72f4:c0a8:600]) (user=jstultz job=sendgmr) by 2002:a17:902:d48a:b0:205:76b1:1765 with SMTP id d9443c01a7336-20c80492808mr175775ad.3.1728518041224; Wed, 09 Oct 2024 16:54:01 -0700 (PDT) Date: Wed, 9 Oct 2024 16:53:35 -0700 In-Reply-To: <20241009235352.1614323-1-jstultz@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20241009235352.1614323-1-jstultz@google.com> X-Mailer: git-send-email 2.47.0.rc0.187.ge670bccf7e-goog Message-ID: <20241009235352.1614323-3-jstultz@google.com> Subject: [RESEND x3][PATCH v12 2/7] locking/mutex: Make mutex::wait_lock irq safe From: John Stultz To: LKML Cc: Juri Lelli , Joel Fernandes , Qais Yousef , Ingo Molnar , Peter Zijlstra , Vincent Guittot , Dietmar Eggemann , Valentin Schneider , Steven Rostedt , Ben Segall , Zimuzo Ezeozue , Mel Gorman , Will Deacon , Waiman Long , Boqun Feng , "Paul E. McKenney" , Metin Kaya , Xuewen Yan , K Prateek Nayak , Thomas Gleixner , Daniel Lezcano , kernel-team@android.com, Metin Kaya , "Connor O'Brien" , John Stultz Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: Juri Lelli mutex::wait_lock might be nested under rq->lock. Make it irq safe then. Cc: Joel Fernandes Cc: Qais Yousef Cc: Ingo Molnar Cc: Peter Zijlstra Cc: Juri Lelli Cc: Vincent Guittot Cc: Dietmar Eggemann Cc: Valentin Schneider Cc: Steven Rostedt Cc: Ben Segall Cc: Zimuzo Ezeozue Cc: Mel Gorman Cc: Will Deacon Cc: Waiman Long Cc: Boqun Feng Cc: "Paul E. McKenney" Cc: Metin Kaya Cc: Xuewen Yan Cc: K Prateek Nayak Cc: Thomas Gleixner Cc: Daniel Lezcano Cc: kernel-team@android.com Tested-by: K Prateek Nayak Tested-by: Metin Kaya Reviewed-by: Metin Kaya Reviewed-by: Valentin Schneider Signed-off-by: Juri Lelli Signed-off-by: Peter Zijlstra (Intel) [rebase & fix {un,}lock_wait_lock helpers in ww_mutex.h] Signed-off-by: Connor O'Brien Signed-off-by: John Stultz --- v3: * Re-added this patch after it was dropped in v2 which caused lockdep warnings to trip. v7: * Fix function definition for PREEMPT_RT case, as pointed out by Metin Kaya. * Fix incorrect flags handling in PREEMPT_RT case as found by Metin Kaya --- kernel/locking/mutex.c | 18 ++++++++++-------- kernel/locking/ww_mutex.h | 21 +++++++++++---------- 2 files changed, 21 insertions(+), 18 deletions(-) diff --git a/kernel/locking/mutex.c b/kernel/locking/mutex.c index 6c94da061ec2..cd248d1767eb 100644 --- a/kernel/locking/mutex.c +++ b/kernel/locking/mutex.c @@ -578,6 +578,7 @@ __mutex_lock_common(struct mutex *lock, unsigned int st= ate, unsigned int subclas DEFINE_WAKE_Q(wake_q); struct mutex_waiter waiter; struct ww_mutex *ww; + unsigned long flags; int ret; =20 if (!use_ww_ctx) @@ -620,7 +621,7 @@ __mutex_lock_common(struct mutex *lock, unsigned int st= ate, unsigned int subclas return 0; } =20 - raw_spin_lock(&lock->wait_lock); + raw_spin_lock_irqsave(&lock->wait_lock, flags); /* * After waiting to acquire the wait_lock, try again. */ @@ -681,7 +682,7 @@ __mutex_lock_common(struct mutex *lock, unsigned int st= ate, unsigned int subclas goto err; } =20 - raw_spin_unlock(&lock->wait_lock); + raw_spin_unlock_irqrestore(&lock->wait_lock, flags); /* Make sure we do wakeups before calling schedule */ wake_up_q(&wake_q); wake_q_init(&wake_q); @@ -706,9 +707,9 @@ __mutex_lock_common(struct mutex *lock, unsigned int st= ate, unsigned int subclas trace_contention_begin(lock, LCB_F_MUTEX); } =20 - raw_spin_lock(&lock->wait_lock); + raw_spin_lock_irqsave(&lock->wait_lock, flags); } - raw_spin_lock(&lock->wait_lock); + raw_spin_lock_irqsave(&lock->wait_lock, flags); acquired: __set_current_state(TASK_RUNNING); =20 @@ -734,7 +735,7 @@ __mutex_lock_common(struct mutex *lock, unsigned int st= ate, unsigned int subclas if (ww_ctx) ww_mutex_lock_acquired(ww, ww_ctx); =20 - raw_spin_unlock(&lock->wait_lock); + raw_spin_unlock_irqrestore(&lock->wait_lock, flags); wake_up_q(&wake_q); preempt_enable(); return 0; @@ -744,7 +745,7 @@ __mutex_lock_common(struct mutex *lock, unsigned int st= ate, unsigned int subclas __mutex_remove_waiter(lock, &waiter); err_early_kill: trace_contention_end(lock, ret); - raw_spin_unlock(&lock->wait_lock); + raw_spin_unlock_irqrestore(&lock->wait_lock, flags); debug_mutex_free_waiter(&waiter); mutex_release(&lock->dep_map, ip); wake_up_q(&wake_q); @@ -915,6 +916,7 @@ static noinline void __sched __mutex_unlock_slowpath(st= ruct mutex *lock, unsigne struct task_struct *next =3D NULL; DEFINE_WAKE_Q(wake_q); unsigned long owner; + unsigned long flags; =20 mutex_release(&lock->dep_map, ip); =20 @@ -941,7 +943,7 @@ static noinline void __sched __mutex_unlock_slowpath(st= ruct mutex *lock, unsigne } } =20 - raw_spin_lock(&lock->wait_lock); + raw_spin_lock_irqsave(&lock->wait_lock, flags); debug_mutex_unlock(lock); if (!list_empty(&lock->wait_list)) { /* get the first entry from the wait-list: */ @@ -959,7 +961,7 @@ static noinline void __sched __mutex_unlock_slowpath(st= ruct mutex *lock, unsigne __mutex_handoff(lock, next); =20 preempt_disable(); - raw_spin_unlock(&lock->wait_lock); + raw_spin_unlock_irqrestore(&lock->wait_lock, flags); wake_up_q(&wake_q); preempt_enable(); } diff --git a/kernel/locking/ww_mutex.h b/kernel/locking/ww_mutex.h index a54bd16d0f17..37f025a096c9 100644 --- a/kernel/locking/ww_mutex.h +++ b/kernel/locking/ww_mutex.h @@ -70,14 +70,14 @@ __ww_mutex_has_waiters(struct mutex *lock) return atomic_long_read(&lock->owner) & MUTEX_FLAG_WAITERS; } =20 -static inline void lock_wait_lock(struct mutex *lock) +static inline void lock_wait_lock(struct mutex *lock, unsigned long *flags) { - raw_spin_lock(&lock->wait_lock); + raw_spin_lock_irqsave(&lock->wait_lock, *flags); } =20 -static inline void unlock_wait_lock(struct mutex *lock) +static inline void unlock_wait_lock(struct mutex *lock, unsigned long *fla= gs) { - raw_spin_unlock(&lock->wait_lock); + raw_spin_unlock_irqrestore(&lock->wait_lock, *flags); } =20 static inline void lockdep_assert_wait_lock_held(struct mutex *lock) @@ -144,14 +144,14 @@ __ww_mutex_has_waiters(struct rt_mutex *lock) return rt_mutex_has_waiters(&lock->rtmutex); } =20 -static inline void lock_wait_lock(struct rt_mutex *lock) +static inline void lock_wait_lock(struct rt_mutex *lock, unsigned long *fl= ags) { - raw_spin_lock(&lock->rtmutex.wait_lock); + raw_spin_lock_irqsave(&lock->rtmutex.wait_lock, *flags); } =20 -static inline void unlock_wait_lock(struct rt_mutex *lock) +static inline void unlock_wait_lock(struct rt_mutex *lock, unsigned long *= flags) { - raw_spin_unlock(&lock->rtmutex.wait_lock); + raw_spin_unlock_irqrestore(&lock->rtmutex.wait_lock, *flags); } =20 static inline void lockdep_assert_wait_lock_held(struct rt_mutex *lock) @@ -380,6 +380,7 @@ static __always_inline void ww_mutex_set_context_fastpath(struct ww_mutex *lock, struct ww_acquire_ctx= *ctx) { DEFINE_WAKE_Q(wake_q); + unsigned long flags; =20 ww_mutex_lock_acquired(lock, ctx); =20 @@ -408,10 +409,10 @@ ww_mutex_set_context_fastpath(struct ww_mutex *lock, = struct ww_acquire_ctx *ctx) * Uh oh, we raced in fastpath, check if any of the waiters need to * die or wound us. */ - lock_wait_lock(&lock->base); + lock_wait_lock(&lock->base, &flags); __ww_mutex_check_waiters(&lock->base, ctx, &wake_q); preempt_disable(); - unlock_wait_lock(&lock->base); + unlock_wait_lock(&lock->base, &flags); wake_up_q(&wake_q); preempt_enable(); } --=20 2.47.0.rc0.187.ge670bccf7e-goog