On 08/20/2013 12:10 PM, Paul E. McKenney wrote: > On Tue, Aug 20, 2013 at 11:50:02AM +0800, Chen Gang wrote: >> According to the comment above rcu_cpu_has_callbacks(): "If there are >> no callbacks, all of them are deemed to be lazy". >> >> So when both 'hc' and 'al' are false, '*all_lazy' should be true, not >> false. > > If there are no callbacks, what must the value of "al" be at this > point in the code? Given this, what is the effect of your patch? >
Hmm... I find it by reading code, the 'C code' says that 'hc' and 'al' has no relationships with each other, so for a reader they can assume when 'hc' is false, 'al' can be either 'true' or 'false'. > Thanx, Paul > >> Signed-off-by: Chen Gang <gang.c...@asianux.com> >> --- >> kernel/rcutree.c | 2 +- >> 1 files changed, 1 insertions(+), 1 deletions(-) >> >> diff --git a/kernel/rcutree.c b/kernel/rcutree.c >> index 5b53a89..9ee9565 100644 >> --- a/kernel/rcutree.c >> +++ b/kernel/rcutree.c >> @@ -2725,7 +2725,7 @@ static int rcu_cpu_has_callbacks(int cpu, bool >> *all_lazy) >> hc = true; >> } >> if (all_lazy) >> - *all_lazy = al; >> + *all_lazy = !hc ? true : al; >> return hc; >> } >> >> -- >> 1.7.7.6 >> > > > -- Chen Gang -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
