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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" Subject: [PATCH tip/core/rcu 15/15] rcu: RCU_SAVE_DYNTICK code no longer ever dead Date: Fri, 15 Jun 2012 14:06:10 -0700 Message-Id: <1339794370-28119-15-git-send-email-paulmck@linux.vnet.ibm.com> X-Mailer: git-send-email 1.7.8 In-Reply-To: <1339794370-28119-1-git-send-email-paulmck@linux.vnet.ibm.com> References: <20120615210550.GA27506@linux.vnet.ibm.com> <1339794370-28119-1-git-send-email-paulmck@linux.vnet.ibm.com> X-Content-Scanned: Fidelis XPS MAILER x-cbid: 12061521-5112-0000-0000-000009145821 X-Gm-Message-State: ALoCoQmN/kwK/eEvUuyNt3MklJWZr3b/5oowaNm96uPGxeH4pH0UjhhDpMZm8WkqoSiY63MharUb 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 75ad92a..0b0c9cc 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 */