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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, niv@us.ibm.com, tglx@linutronix.de, peterz@infradead.org, rostedt@goodmis.org, Valdis.Kletnieks@vt.edu, dhowells@redhat.com, eric.dumazet@gmail.com, darren@dvhart.com, fweisbec@gmail.com, patches@linaro.org, "Paul E. McKenney" , "Paul E. McKenney" Subject: [PATCH rcu 6/8] rcu: The rcu_needs_cpu() function is not a quiescent state Date: Thu, 7 Jun 2012 21:26:53 -0700 Message-Id: <1339129615-1795-6-git-send-email-paulmck@linux.vnet.ibm.com> X-Mailer: git-send-email 1.7.8 In-Reply-To: <1339129615-1795-1-git-send-email-paulmck@linux.vnet.ibm.com> References: <20120608042632.GA1250@linux.vnet.ibm.com> <1339129615-1795-1-git-send-email-paulmck@linux.vnet.ibm.com> X-Content-Scanned: Fidelis XPS MAILER x-cbid: 12060804-4242-0000-0000-000001E80104 X-Gm-Message-State: ALoCoQltoK2pCIG7njAJIluE1cjKIoUs2dRnimU5n0+K2axIJdEaKtYPMW7losgqoSGwtyYqXcTc From: "Paul E. McKenney" The TINY_PREEMPT_RCU() function rcu_preempt_needs_cpu(), which is called from rcu_needs_cpu(), assumes that it is in a quiescent state with respect to the CPU. This is no longer the case. This commit therefore updates rcu_preempt_needs_cpu() to make it aware that it is not running in a quiescent state. Signed-off-by: Paul E. McKenney Signed-off-by: Paul E. McKenney Tested-by: Heiko Carstens Tested-by: Pascal Chapperon --- kernel/rcutiny_plugin.h | 2 -- 1 files changed, 0 insertions(+), 2 deletions(-) diff --git a/kernel/rcutiny_plugin.h b/kernel/rcutiny_plugin.h index fc31a2d..849ede5 100644 --- a/kernel/rcutiny_plugin.h +++ b/kernel/rcutiny_plugin.h @@ -846,8 +846,6 @@ EXPORT_SYMBOL_GPL(synchronize_rcu_expedited); */ int rcu_preempt_needs_cpu(void) { - if (!rcu_preempt_running_reader()) - rcu_preempt_cpu_qs(); return rcu_preempt_ctrlblk.rcb.rcucblist != NULL; }