From 15ff48e7210c4c592781bd5277b9b3dbb718b060 Mon Sep 17 00:00:00 2001 From: Takashi Sakamoto Date: Fri, 15 Jul 2016 09:23:07 +0900 Subject: mixer: remove alloca() from elem_read_volume() Both of alloca() and automatic variables keep storages on stack, while the former generates more instructions than the latter. It's better to use the latter if the size of storage is computable at pre-compile or compile time; i.e. just for structures. This commit obsolete usages of alloca() with automatic variables. Signed-off-by: Takashi Sakamoto Signed-off-by: Takashi Iwai --- src/mixer/simple_none.c | 14 ++++++-------- 1 file changed, 6 insertions(+), 8 deletions(-) diff --git a/src/mixer/simple_none.c b/src/mixer/simple_none.c index a90ee84c..0f23a063 100644 --- a/src/mixer/simple_none.c +++ b/src/mixer/simple_none.c @@ -234,12 +234,11 @@ static long from_user(selem_none_t *s, int dir, selem_ctl_t *c, long value) static int elem_read_volume(selem_none_t *s, int dir, selem_ctl_type_t type) { - snd_ctl_elem_value_t *ctl; + snd_ctl_elem_value_t ctl = {0}; unsigned int idx; int err; selem_ctl_t *c = &s->ctls[type]; - snd_ctl_elem_value_alloca(&ctl); - if ((err = snd_hctl_elem_read(c->elem, ctl)) < 0) + if ((err = snd_hctl_elem_read(c->elem, &ctl)) < 0) return err; for (idx = 0; idx < s->str[dir].channels; idx++) { unsigned int idx1 = idx; @@ -247,25 +246,24 @@ static int elem_read_volume(selem_none_t *s, int dir, selem_ctl_type_t type) idx1 = 0; s->str[dir].vol[idx] = to_user(s, dir, c, - snd_ctl_elem_value_get_integer(ctl, idx1)); + snd_ctl_elem_value_get_integer(&ctl, idx1)); } return 0; } static int elem_read_switch(selem_none_t *s, int dir, selem_ctl_type_t type) { - snd_ctl_elem_value_t *ctl; + snd_ctl_elem_value_t ctl = {0}; unsigned int idx; int err; selem_ctl_t *c = &s->ctls[type]; - snd_ctl_elem_value_alloca(&ctl); - if ((err = snd_hctl_elem_read(c->elem, ctl)) < 0) + if ((err = snd_hctl_elem_read(c->elem, &ctl)) < 0) return err; for (idx = 0; idx < s->str[dir].channels; idx++) { unsigned int idx1 = idx; if (idx >= c->values) idx1 = 0; - if (!snd_ctl_elem_value_get_integer(ctl, idx1)) + if (!snd_ctl_elem_value_get_integer(&ctl, idx1)) s->str[dir].sw &= ~(1 << idx); } return 0; -- cgit v1.2.1