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pwm: Reduce number of pointer dereferences in pwm_device_request()

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pwm->chip and pwm->chip->ops are used several times in this function.
Introduce local variables for these.

There is no semantical change, but with ARCH=arm, allmodconfig and
gcc-13 bloat-o-meter reports a slight improvement:

	add/remove: 1/1 grow/shrink: 1/1 up/down: 8/-36 (-28)
	Function                                     old     new   delta
	pwm_apply_state                              476     480      +4
	__initcall__kmod_core__307_1092_pwm_debugfs_init4       -       4      +4
	__initcall__kmod_core__307_1090_pwm_debugfs_init4       4       -      -4
	pwm_request_from_chip                        628     596     -32
	Total: Before=15091, After=15063, chg -0.19%

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
This commit is contained in:
Uwe Kleine-König 2023-11-30 08:21:06 +01:00 committed by Thierry Reding
parent d243221dc9
commit efb704abed
1 changed files with 8 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

14
drivers/pwm/core.c
View File

@ -59,22 +59,24 @@ static struct pwm_chip *pwmchip_find_by_name(const char *name)
static int pwm_device_request(struct pwm_device *pwm, const char *label)
{
int err;
struct pwm_chip *chip = pwm->chip;
const struct pwm_ops *ops = chip->ops;
if (test_bit(PWMF_REQUESTED, &pwm->flags))
return -EBUSY;
if (!try_module_get(pwm->chip->owner))
if (!try_module_get(chip->owner))
return -ENODEV;
if (pwm->chip->ops->request) {
err = pwm->chip->ops->request(pwm->chip, pwm);
if (ops->request) {
err = ops->request(chip, pwm);
if (err) {
module_put(pwm->chip->owner);
module_put(chip->owner);
return err;
}
}
if (pwm->chip->ops->get_state) {
if (ops->get_state) {
/*
* Zero-initialize state because most drivers are unaware of
* .usage_power. The other members of state are supposed to be
@ -84,7 +86,7 @@ static int pwm_device_request(struct pwm_device *pwm, const char *label)
*/
struct pwm_state state = { 0, };
err = pwm->chip->ops->get_state(pwm->chip, pwm, &state);
err = ops->get_state(chip, pwm, &state);
trace_pwm_get(pwm, &state, err);
if (!err)