From: Pranith Kumar <bobby.prani@gmail.com>
To: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
Josh Triplett <josh@joshtriplett.org>,
Steven Rostedt <rostedt@goodmis.org>,
Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
Lai Jiangshan <laijs@cn.fujitsu.com>,
linux-kernel@vger.kernel.org (open list:READ-COPY UPDATE...)
Subject: [PATCH 11/16] rcu: Check for spurious wakeup using return value
Date: Wed, 23 Jul 2014 01:09:48 -0400 [thread overview]
Message-ID: <1406092194-13004-12-git-send-email-bobby.prani@gmail.com> (raw)
In-Reply-To: <1406092194-13004-1-git-send-email-bobby.prani@gmail.com>
When the gp_kthread wakes up from the wait event, it returns 0 if the wake up is
due to the condition having been met. This commit checks this return value
for a spurious wake up before calling rcu_gp_init().
Signed-off-by: Pranith Kumar <bobby.prani@gmail.com>
---
kernel/rcu/tree.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index f8847d9..3b20ad2 100644
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -1790,11 +1790,11 @@ static int __noreturn rcu_gp_kthread(void *arg)
ACCESS_ONCE(rsp->gpnum),
TPS("reqwait"));
rsp->gp_state = RCU_GP_WAIT_GPS;
- wait_event_interruptible(rsp->gp_wq,
+ ret = wait_event_interruptible(rsp->gp_wq,
ACCESS_ONCE(rsp->gp_flags) &
RCU_GP_FLAG_INIT);
/* Locking provides needed memory barrier. */
- if (rcu_gp_init(rsp))
+ if (!ret && rcu_gp_init(rsp))
break;
cond_resched();
flush_signals(current);
--
2.0.0.rc2
next prev parent reply other threads:[~2014-07-23 5:12 UTC|newest]
Thread overview: 58+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-07-23 5:09 [PATCH 00/16] rcu: Some minor fixes and cleanups Pranith Kumar
2014-07-23 5:09 ` [PATCH 01/16] rcu: Use rcu_num_nodes instead of NUM_RCU_NODES Pranith Kumar
2014-07-23 5:09 ` [PATCH 02/16] rcu: Check return value for cpumask allocation Pranith Kumar
2014-07-23 12:06 ` Paul E. McKenney
2014-07-23 12:49 ` Pranith Kumar
2014-07-23 17:14 ` Pranith Kumar
2014-07-23 18:01 ` Paul E. McKenney
2014-07-23 5:09 ` [PATCH 03/16] rcu: Fix comment for gp_state field values Pranith Kumar
2014-07-23 5:09 ` [PATCH 04/16] rcu: Remove redundant check for an online CPU Pranith Kumar
2014-07-23 12:09 ` Paul E. McKenney
2014-07-23 13:23 ` Pranith Kumar
2014-07-23 13:41 ` Paul E. McKenney
2014-07-23 14:01 ` Pranith Kumar
2014-07-23 14:14 ` Paul E. McKenney
2014-07-23 15:07 ` Pranith Kumar
2014-07-23 15:21 ` Pranith Kumar
2014-07-23 5:09 ` [PATCH 05/16] rcu: Add noreturn attribute to boost kthread Pranith Kumar
2014-07-23 5:09 ` [PATCH 06/16] rcu: Clear gp_flags only when actually starting new gp Pranith Kumar
2014-07-23 12:13 ` Paul E. McKenney
2014-07-23 5:09 ` [PATCH 07/16] rcu: Save and restore irq flags in rcu_gp_cleanup() Pranith Kumar
2014-07-23 12:16 ` Paul E. McKenney
2014-07-23 5:09 ` [PATCH 08/16] rcu: Clean up rcu_spawn_one_boost_kthread() Pranith Kumar
2014-07-23 5:09 ` [PATCH 09/16] rcu: Remove redundant check for online cpu Pranith Kumar
2014-07-23 12:21 ` Paul E. McKenney
2014-07-23 12:59 ` Pranith Kumar
2014-07-23 13:50 ` Paul E. McKenney
2014-07-23 14:12 ` Pranith Kumar
2014-07-23 14:23 ` Paul E. McKenney
2014-07-23 15:11 ` Pranith Kumar
2014-07-23 15:30 ` Paul E. McKenney
2014-07-23 15:44 ` Pranith Kumar
2014-07-23 19:15 ` Paul E. McKenney
2014-07-23 20:01 ` Pranith Kumar
2014-07-23 20:16 ` Pranith Kumar
2014-07-23 20:23 ` Paul E. McKenney
2014-07-23 5:09 ` [PATCH 10/16] rcu: Check for RCU_FLAG_GP_INIT bit in gp_flags for spurious wakeup Pranith Kumar
2014-07-23 12:23 ` Paul E. McKenney
2014-07-23 5:09 ` Pranith Kumar [this message]
2014-07-23 12:26 ` [PATCH 11/16] rcu: Check for spurious wakeup using return value Paul E. McKenney
2014-07-24 2:36 ` Pranith Kumar
2014-07-24 3:43 ` Paul E. McKenney
2014-07-24 4:03 ` Pranith Kumar
2014-07-24 18:12 ` Paul E. McKenney
2014-07-24 19:59 ` Pranith Kumar
2014-07-24 20:27 ` Paul E. McKenney
2014-07-23 5:09 ` [PATCH 12/16] rcu: Rename rcu_spawn_gp_kthread() to rcu_spawn_kthreads() Pranith Kumar
2014-07-23 5:09 ` [PATCH 13/16] rcu: Spawn nocb kthreads from rcu_prepare_kthreads() Pranith Kumar
2014-07-23 5:09 ` [PATCH 14/16] rcu: Remove redundant checks for rcu_scheduler_fully_active Pranith Kumar
2014-07-23 12:27 ` Paul E. McKenney
2014-07-23 5:09 ` [PATCH 15/16] rcu: Check for a nocb cpu before trying to spawn nocb threads Pranith Kumar
2014-07-23 12:28 ` Paul E. McKenney
2014-07-23 13:14 ` Pranith Kumar
2014-07-23 13:42 ` Paul E. McKenney
2014-07-23 5:09 ` [PATCH 16/16] rcu: kvm.sh: Fix error when you pass --cpus argument Pranith Kumar
2014-07-23 12:31 ` Paul E. McKenney
2014-07-23 14:45 ` [PATCH 00/16] rcu: Some minor fixes and cleanups Paul E. McKenney
2014-08-27 1:10 ` Pranith Kumar
2014-08-27 3:20 ` Paul E. McKenney
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