| Message ID | b9bb3a40fc7a973438a54ddab8e1c89c6c66dd8c.1397492345.git.viresh.kumar@linaro.org |
|---|---|
| State | New |
| Headers | show |
On Mon, Apr 14, 2014 at 09:53:52PM +0530, Viresh Kumar wrote: > nohz_full_buf[] is used at only one place, i.e. inside tick_nohz_init(). Make it > a local variable. Can move it out in case it is used in some other routines in > future. OTOH nohz_full_buf can have a big size and moving it to a local variable will result in big increase in kernel stack consumption. Keeping it static is safer. Also it's already __initdata so it's released after bootup. No issue of concurrent use either, so keeping it as is is fine. > > Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> > --- > kernel/time/tick-sched.c | 13 ++++++------- > 1 file changed, 6 insertions(+), 7 deletions(-) > > diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c > index d8b9a69..22b9505 100644 > --- a/kernel/time/tick-sched.c > +++ b/kernel/time/tick-sched.c > @@ -321,13 +321,6 @@ static int tick_nohz_cpu_down_callback(struct notifier_block *nfb, > return NOTIFY_OK; > } > > -/* > - * Worst case string length in chunks of CPU range seems 2 steps > - * separations: 0,2,4,6,... > - * This is NR_CPUS + sizeof('\0') > - */ > -static char __initdata nohz_full_buf[NR_CPUS + 1]; > - > static int tick_nohz_init_all(void) > { > int err = -1; > @@ -347,6 +340,12 @@ static int tick_nohz_init_all(void) > > void __init tick_nohz_init(void) > { > + /* > + * Worst case string length in chunks of CPU range seems 2 steps > + * separations: 0,2,4,6,... > + * This is NR_CPUS + sizeof('\0') > + */ > + char nohz_full_buf[NR_CPUS + 1]; > int cpu; > > if (!tick_nohz_full_running) { > -- > 1.7.12.rc2.18.g61b472e > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
On 15 April 2014 04:58, Frederic Weisbecker <fweisbec@gmail.com> wrote: > OTOH nohz_full_buf can have a big size and moving it to a local variable > will result in big increase in kernel stack consumption. > > Keeping it static is safer. > > Also it's already __initdata so it's released after bootup. No issue of > concurrent use either, so keeping it as is is fine. Okay, this patch is dropped. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c index d8b9a69..22b9505 100644 --- a/kernel/time/tick-sched.c +++ b/kernel/time/tick-sched.c @@ -321,13 +321,6 @@ static int tick_nohz_cpu_down_callback(struct notifier_block *nfb, return NOTIFY_OK; } -/* - * Worst case string length in chunks of CPU range seems 2 steps - * separations: 0,2,4,6,... - * This is NR_CPUS + sizeof('\0') - */ -static char __initdata nohz_full_buf[NR_CPUS + 1]; - static int tick_nohz_init_all(void) { int err = -1; @@ -347,6 +340,12 @@ static int tick_nohz_init_all(void) void __init tick_nohz_init(void) { + /* + * Worst case string length in chunks of CPU range seems 2 steps + * separations: 0,2,4,6,... + * This is NR_CPUS + sizeof('\0') + */ + char nohz_full_buf[NR_CPUS + 1]; int cpu; if (!tick_nohz_full_running) {
nohz_full_buf[] is used at only one place, i.e. inside tick_nohz_init(). Make it a local variable. Can move it out in case it is used in some other routines in future. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> --- kernel/time/tick-sched.c | 13 ++++++------- 1 file changed, 6 insertions(+), 7 deletions(-)