From ac1c02f167ece50c933392e6853f198003ddfd8a Mon Sep 17 00:00:00 2001 From: Frederic Weisbecker Date: Wed, 22 Aug 2012 17:27:34 +0200 Subject: m32r: Add missing RCU idle APIs on idle loop commit 48ae077cfce72591b8fc80e1dcc87806f86fed7f upstream. In the old times, the whole idle task was considered as an RCU quiescent state. But as RCU became more and more successful overtime, some RCU read side critical section have been added even in the code of some architectures idle tasks, for tracing for example. So nowadays, rcu_idle_enter() and rcu_idle_exit() must be called by the architecture to tell RCU about the part in the idle loop that doesn't make use of rcu read side critical sections, typically the part that puts the CPU in low power mode. This is necessary for RCU to find the quiescent states in idle in order to complete grace periods. Add this missing pair of calls in the m32r's idle loop. Reported-by: Paul E. McKenney Signed-off-by: Frederic Weisbecker Cc: Hirokazu Takata Signed-off-by: Paul E. McKenney Reviewed-by: Josh Triplett Signed-off-by: Greg Kroah-Hartman --- arch/m32r/kernel/process.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'arch') diff --git a/arch/m32r/kernel/process.c b/arch/m32r/kernel/process.c index 3a4a32b27208..384e63f3a4c4 100644 --- a/arch/m32r/kernel/process.c +++ b/arch/m32r/kernel/process.c @@ -26,6 +26,7 @@ #include #include #include +#include #include #include @@ -82,6 +83,7 @@ void cpu_idle (void) { /* endless idle loop with no priority at all */ while (1) { + rcu_idle_enter(); while (!need_resched()) { void (*idle)(void) = pm_idle; @@ -90,6 +92,7 @@ void cpu_idle (void) idle(); } + rcu_idle_exit(); schedule_preempt_disabled(); } } -- cgit v1.2.3