From: Zhouyi Zhou <zhouzho...@gmail.com> Because RCU avoids interrupting idle CPUs, rcu_is_watching is used to test whether or not it is currently legal to run RCU read-side critical sections on this CPU.
First sentence and last sentence of current comment for rcu_is_watching have opposite meaning of what is expected. Signed-off-by: Zhouyi Zhou <zhouzho...@gmail.com> --- kernel/rcu/tree.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index 0b760c1..adb04ea 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -1010,12 +1010,12 @@ void rcu_irq_enter_irqson(void) } /** - * rcu_is_watching - see if RCU thinks that the current CPU is idle + * rcu_is_watching - see if RCU thinks that the current CPU is not idle * * Return true if RCU is watching the running CPU, which means that this * CPU can safely enter RCU read-side critical sections. In other words, - * if the current CPU is in its idle loop and is neither in an interrupt - * or NMI handler, return true. + * if the current CPU is not in its idle loop or is in an interrupt or + * NMI handler, return true. */ bool notrace rcu_is_watching(void) { -- 2.1.4