path: root/arch/mn10300/kernel
diff options
authorFrederic Weisbecker <>2012-08-22 17:27:34 +0200
committerPaul E. McKenney <>2012-09-23 07:44:48 -0700
commit5b0753a90b7a98bc613c3767e9263a1a76d4f900 (patch)
tree5d80491cc2483616122e99cf351839525d0e70e6 /arch/mn10300/kernel
parent5b57ba37e82a15f345a6a2eb8c01a2b2d94c5eeb (diff)
mn10300: Add missing RCU idle APIs on idle loop
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 mn10300's idle loop. Reported-by: Paul E. McKenney <> Signed-off-by: Frederic Weisbecker <> Cc: David Howells <> Cc: Koichi Yasutake <> Cc: <> # 3.3+ Signed-off-by: Paul E. McKenney <> Acked-by: David Howells <> Reviewed-by: Josh Triplett <>
Diffstat (limited to 'arch/mn10300/kernel')
1 files changed, 3 insertions, 0 deletions
diff --git a/arch/mn10300/kernel/process.c b/arch/mn10300/kernel/process.c
index 7dab0cd36466..e9cceba193b6 100644
--- a/arch/mn10300/kernel/process.c
+++ b/arch/mn10300/kernel/process.c
@@ -25,6 +25,7 @@
#include <linux/err.h>
#include <linux/fs.h>
#include <linux/slab.h>
+#include <linux/rcupdate.h>
#include <asm/uaccess.h>
#include <asm/pgtable.h>
#include <asm/io.h>
@@ -107,6 +108,7 @@ void cpu_idle(void)
/* endless idle loop with no priority at all */
for (;;) {
+ rcu_idle_enter();
while (!need_resched()) {
void (*idle)(void);
@@ -121,6 +123,7 @@ void cpu_idle(void)
+ rcu_idle_exit();