From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1425338AbdEYWMb (ORCPT ); Thu, 25 May 2017 18:12:31 -0400 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:57489 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S943075AbdEYWAP (ORCPT ); Thu, 25 May 2017 18:00:15 -0400 From: "Paul E. McKenney" To: linux-kernel@vger.kernel.org Cc: mingo@kernel.org, jiangshanlai@gmail.com, dipankar@in.ibm.com, akpm@linux-foundation.org, mathieu.desnoyers@efficios.com, josh@joshtriplett.org, tglx@linutronix.de, peterz@infradead.org, rostedt@goodmis.org, dhowells@redhat.com, edumazet@google.com, fweisbec@gmail.com, oleg@redhat.com, bobby.prani@gmail.com, "Paul E. McKenney" Subject: [PATCH tip/core/rcu 72/88] rcu: Move rnp->lock wrappers for SRCU use Date: Thu, 25 May 2017 14:59:45 -0700 X-Mailer: git-send-email 2.5.2 In-Reply-To: <20170525215934.GA11578@linux.vnet.ibm.com> References: <20170525215934.GA11578@linux.vnet.ibm.com> X-TM-AS-GCONF: 00 x-cbid: 17052522-0040-0000-0000-0000034A371C X-IBM-SpamModules-Scores: X-IBM-SpamModules-Versions: BY=3.00007117; HX=3.00000241; KW=3.00000007; PH=3.00000004; SC=3.00000212; SDB=6.00865574; UDB=6.00429834; IPR=6.00645397; BA=6.00005375; NDR=6.00000001; ZLA=6.00000005; ZF=6.00000009; ZB=6.00000000; ZP=6.00000000; ZH=6.00000000; ZU=6.00000002; MB=3.00015583; XFM=3.00000015; UTC=2017-05-25 22:00:12 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 17052522-0041-0000-0000-0000073E6D52 Message-Id: <1495749601-21574-72-git-send-email-paulmck@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2017-05-25_17:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=1 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1703280000 definitions=main-1705250401 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This commit moves the now-generic rnp->lock wrapper macros from kernel/rcu/tree.h to kernel/rcu/rcu.h, thus allowing SRCU to use them. Signed-off-by: Paul E. McKenney --- kernel/rcu/rcu.h | 53 +++++++++++++++++++++++++++++++++++++++++++++++++++++ kernel/rcu/tree.h | 53 ----------------------------------------------------- 2 files changed, 53 insertions(+), 53 deletions(-) diff --git a/kernel/rcu/rcu.h b/kernel/rcu/rcu.h index 6a1e85bd2eac..2a75beb883c8 100644 --- a/kernel/rcu/rcu.h +++ b/kernel/rcu/rcu.h @@ -303,6 +303,59 @@ static inline void rcu_init_levelspread(int *levelspread, const int *levelcnt) cpu <= rnp->grphi; \ cpu = cpumask_next((cpu), cpu_possible_mask)) +/* + * Wrappers for the rcu_node::lock acquire and release. + * + * Because the rcu_nodes form a tree, the tree traversal locking will observe + * different lock values, this in turn means that an UNLOCK of one level + * followed by a LOCK of another level does not imply a full memory barrier; + * and most importantly transitivity is lost. + * + * In order to restore full ordering between tree levels, augment the regular + * lock acquire functions with smp_mb__after_unlock_lock(). + * + * As ->lock of struct rcu_node is a __private field, therefore one should use + * these wrappers rather than directly call raw_spin_{lock,unlock}* on ->lock. + */ +#define raw_spin_lock_rcu_node(p) \ +do { \ + raw_spin_lock(&ACCESS_PRIVATE(p, lock)); \ + smp_mb__after_unlock_lock(); \ +} while (0) + +#define raw_spin_unlock_rcu_node(p) raw_spin_unlock(&ACCESS_PRIVATE(p, lock)) + +#define raw_spin_lock_irq_rcu_node(p) \ +do { \ + raw_spin_lock_irq(&ACCESS_PRIVATE(p, lock)); \ + smp_mb__after_unlock_lock(); \ +} while (0) + +#define raw_spin_unlock_irq_rcu_node(p) \ + raw_spin_unlock_irq(&ACCESS_PRIVATE(p, lock)) + +#define raw_spin_lock_irqsave_rcu_node(rnp, flags) \ +do { \ + typecheck(unsigned long, flags); \ + raw_spin_lock_irqsave(&ACCESS_PRIVATE(rnp, lock), flags); \ + smp_mb__after_unlock_lock(); \ +} while (0) + +#define raw_spin_unlock_irqrestore_rcu_node(rnp, flags) \ +do { \ + typecheck(unsigned long, flags); \ + raw_spin_unlock_irqrestore(&ACCESS_PRIVATE(rnp, lock), flags); \ +} while (0) + +#define raw_spin_trylock_rcu_node(p) \ +({ \ + bool ___locked = raw_spin_trylock(&ACCESS_PRIVATE(p, lock)); \ + \ + if (___locked) \ + smp_mb__after_unlock_lock(); \ + ___locked; \ +}) + #endif /* #if defined(SRCU) || !defined(TINY_RCU) */ #ifdef CONFIG_TINY_RCU diff --git a/kernel/rcu/tree.h b/kernel/rcu/tree.h index a7f63f1074b4..baa0bac8da2a 100644 --- a/kernel/rcu/tree.h +++ b/kernel/rcu/tree.h @@ -565,56 +565,3 @@ static inline void rcu_nocb_q_lengths(struct rcu_data *rdp, long *ql, long *qll) #endif /* #else #ifdef CONFIG_RCU_NOCB_CPU */ } #endif /* #ifdef CONFIG_RCU_TRACE */ - -/* - * Wrappers for the rcu_node::lock acquire and release. - * - * Because the rcu_nodes form a tree, the tree traversal locking will observe - * different lock values, this in turn means that an UNLOCK of one level - * followed by a LOCK of another level does not imply a full memory barrier; - * and most importantly transitivity is lost. - * - * In order to restore full ordering between tree levels, augment the regular - * lock acquire functions with smp_mb__after_unlock_lock(). - * - * As ->lock of struct rcu_node is a __private field, therefore one should use - * these wrappers rather than directly call raw_spin_{lock,unlock}* on ->lock. - */ -#define raw_spin_lock_rcu_node(p) \ -do { \ - raw_spin_lock(&ACCESS_PRIVATE(p, lock)); \ - smp_mb__after_unlock_lock(); \ -} while (0) - -#define raw_spin_unlock_rcu_node(p) raw_spin_unlock(&ACCESS_PRIVATE(p, lock)) - -#define raw_spin_lock_irq_rcu_node(p) \ -do { \ - raw_spin_lock_irq(&ACCESS_PRIVATE(p, lock)); \ - smp_mb__after_unlock_lock(); \ -} while (0) - -#define raw_spin_unlock_irq_rcu_node(p) \ - raw_spin_unlock_irq(&ACCESS_PRIVATE(p, lock)) - -#define raw_spin_lock_irqsave_rcu_node(rnp, flags) \ -do { \ - typecheck(unsigned long, flags); \ - raw_spin_lock_irqsave(&ACCESS_PRIVATE(rnp, lock), flags); \ - smp_mb__after_unlock_lock(); \ -} while (0) - -#define raw_spin_unlock_irqrestore_rcu_node(rnp, flags) \ -do { \ - typecheck(unsigned long, flags); \ - raw_spin_unlock_irqrestore(&ACCESS_PRIVATE(rnp, lock), flags); \ -} while (0) - -#define raw_spin_trylock_rcu_node(p) \ -({ \ - bool ___locked = raw_spin_trylock(&ACCESS_PRIVATE(p, lock)); \ - \ - if (___locked) \ - smp_mb__after_unlock_lock(); \ - ___locked; \ -}) -- 2.5.2