From mboxrd@z Thu Jan 1 00:00:00 1970 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752394AbZI2EuY (ORCPT ); Tue, 29 Sep 2009 00:50:24 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751920AbZI2EuX (ORCPT ); Tue, 29 Sep 2009 00:50:23 -0400 Received: from e4.ny.us.ibm.com ([32.97.182.144]:59712 "EHLO e4.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750826AbZI2EuV (ORCPT ); Tue, 29 Sep 2009 00:50:21 -0400 From: "Paul E. McKenney" To: linux-kernel@vger.kernel.org Cc: mingo@elte.hu, laijs@cn.fujitsu.com, dipankar@in.ibm.com, akpm@linux-foundation.org, mathieu.desnoyers@polymtl.ca, josh@joshtriplett.org, dvhltc@us.ibm.com, niv@us.ibm.com, tglx@linutronix.de, peterz@infradead.org, rostedt@goodmis.org, Valdis.Kletnieks@vt.edu, dhowells@redhat.com, "Paul E. McKenney" Subject: [PATCH tip/core/rcu 1/3] rcu: replace the rcu_barrier enum with pointer to call_rcu*() function Date: Mon, 28 Sep 2009 21:50:21 -0700 Message-Id: <12541998232366-git-send-email-> X-Mailer: git-send-email 1.5.2.5 In-Reply-To: <20090929044955.GA12486@linux.vnet.ibm.com> References: <20090929044955.GA12486@linux.vnet.ibm.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The rcu_barrier enum causes several problems: (1) you have to define the enum somewhere, and there is no convenient place, (2) the difference between TREE_RCU and TREE_PREEMPT_RCU causes problems when you need to map from rcu_barrier enum to struct rcu_state, (3) the switch statement are large, and (4) TINY_RCU really needs a different rcu_barrier() than do the treercu implementations. Signed-off-by: Paul E. McKenney --- kernel/rcupdate.c | 32 ++++++++++---------------------- 1 files changed, 10 insertions(+), 22 deletions(-) diff --git a/kernel/rcupdate.c b/kernel/rcupdate.c index 2480534..fd3ec49 100644 --- a/kernel/rcupdate.c +++ b/kernel/rcupdate.c @@ -53,12 +53,6 @@ struct lockdep_map rcu_lock_map = EXPORT_SYMBOL_GPL(rcu_lock_map); #endif -enum rcu_barrier { - RCU_BARRIER_STD, - RCU_BARRIER_BH, - RCU_BARRIER_SCHED, -}; - static DEFINE_PER_CPU(struct rcu_head, rcu_barrier_head) = {NULL}; static atomic_t rcu_barrier_cpu_count; static DEFINE_MUTEX(rcu_barrier_mutex); @@ -188,19 +182,12 @@ static void rcu_barrier_func(void *type) { int cpu = smp_processor_id(); struct rcu_head *head = &per_cpu(rcu_barrier_head, cpu); + void (*call_rcu_func)(struct rcu_head *head, + void (*func)(struct rcu_head *head)); atomic_inc(&rcu_barrier_cpu_count); - switch ((enum rcu_barrier)type) { - case RCU_BARRIER_STD: - call_rcu(head, rcu_barrier_callback); - break; - case RCU_BARRIER_BH: - call_rcu_bh(head, rcu_barrier_callback); - break; - case RCU_BARRIER_SCHED: - call_rcu_sched(head, rcu_barrier_callback); - break; - } + call_rcu_func = type; + call_rcu_func(head, rcu_barrier_callback); } static inline void wait_migrated_callbacks(void) @@ -213,7 +200,8 @@ static inline void wait_migrated_callbacks(void) * Orchestrate the specified type of RCU barrier, waiting for all * RCU callbacks of the specified type to complete. */ -static void _rcu_barrier(enum rcu_barrier type) +static void _rcu_barrier(void (*call_rcu_func)(struct rcu_head *head, + void (*func)(struct rcu_head *head))) { BUG_ON(in_interrupt()); /* Take cpucontrol mutex to protect against CPU hotplug */ @@ -229,7 +217,7 @@ static void _rcu_barrier(enum rcu_barrier type) * early. */ atomic_set(&rcu_barrier_cpu_count, 1); - on_each_cpu(rcu_barrier_func, (void *)type, 1); + on_each_cpu(rcu_barrier_func, (void *)call_rcu_func, 1); if (atomic_dec_and_test(&rcu_barrier_cpu_count)) complete(&rcu_barrier_completion); wait_for_completion(&rcu_barrier_completion); @@ -242,7 +230,7 @@ static void _rcu_barrier(enum rcu_barrier type) */ void rcu_barrier(void) { - _rcu_barrier(RCU_BARRIER_STD); + _rcu_barrier(call_rcu); } EXPORT_SYMBOL_GPL(rcu_barrier); @@ -251,7 +239,7 @@ EXPORT_SYMBOL_GPL(rcu_barrier); */ void rcu_barrier_bh(void) { - _rcu_barrier(RCU_BARRIER_BH); + _rcu_barrier(call_rcu_bh); } EXPORT_SYMBOL_GPL(rcu_barrier_bh); @@ -260,7 +248,7 @@ EXPORT_SYMBOL_GPL(rcu_barrier_bh); */ void rcu_barrier_sched(void) { - _rcu_barrier(RCU_BARRIER_SCHED); + _rcu_barrier(call_rcu_sched); } EXPORT_SYMBOL_GPL(rcu_barrier_sched); -- 1.5.2.5