On Mon, Dec 18, 2017 at 11:08 AM, Christophe Leroy <[email protected]> wrote:
> A 'perf record' on an app continuously writing in the 'value' > attribute show that most of the time is spent in kstrtol() > > --17.99%--value_store > | > |--10.17%--kstrtoint > | | > | |--8.82%--kstrtoll > | > |--2.50%--gpiod_set_value_cansleep > | > |--1.82%--u16_gpio_set > | > |--1.46%--value_store > > The normal case is to write 0 or 1 in the attribute, therefore > this patch avoids the call to kstrtol() in the most common cases > > Then 'perf record' shows > > --7.21%--value_store > | > |--2.69%--u16_gpio_set > | > |--1.47%--value_store > | > |--1.08%--gpiod_set_value_cansleep > | > |--0.60%--mutex_lock > | > --0.58%--mutex_unlock > > Signed-off-by: Christophe Leroy <[email protected]> Patch applied. Yours, Linus Walleij
