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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, sbw@mit.edu, patches@linaro.org, "Paul E. McKenney" Subject: [PATCH tip/core/rcu 17/22] rcu: RCU_SAVE_DYNTICK code no longer ever dead Date: Fri, 22 Jun 2012 08:17:16 -0700 Message-Id: <1340378241-6458-17-git-send-email-paulmck@linux.vnet.ibm.com> X-Mailer: git-send-email 1.7.8 In-Reply-To: <1340378241-6458-1-git-send-email-paulmck@linux.vnet.ibm.com> References: <20120622151655.GA6249@linux.vnet.ibm.com> <1340378241-6458-1-git-send-email-paulmck@linux.vnet.ibm.com> X-Content-Scanned: Fidelis XPS MAILER x-cbid: 12062215-7182-0000-0000-000001D2B669 X-Gm-Message-State: ALoCoQlyZjbHJnaOpAtDMI4TYHNaP5BCI7pJuyvnuiO8HJDEnhpwLS661tDNY7+ejhqKJceD1xDH From: "Paul E. McKenney" Before RCU had unified idle, the RCU_SAVE_DYNTICK leg of the switch statement in force_quiescent_state() was dead code for CONFIG_NO_HZ=n kernel builds. With unified idle, the code is never dead. This commit therefore removes the "if" statement designed to make gcc aware of when the code was and was not dead. Signed-off-by: Paul E. McKenney Reviewed-by: Josh Triplett --- kernel/rcutree.c | 2 -- 1 files changed, 0 insertions(+), 2 deletions(-) diff --git a/kernel/rcutree.c b/kernel/rcutree.c index 68a9d8b..1b0e441 100644 --- a/kernel/rcutree.c +++ b/kernel/rcutree.c @@ -1744,8 +1744,6 @@ static void force_quiescent_state(struct rcu_state *rsp, int relaxed) break; /* grace period idle or initializing, ignore. */ case RCU_SAVE_DYNTICK: - if (RCU_SIGNAL_INIT != RCU_SAVE_DYNTICK) - break; /* So gcc recognizes the dead code. */ raw_spin_unlock(&rnp->lock); /* irqs remain disabled */