2024-01-20 09:42:41

by Christophe JAILLET

Subject: [PATCH] ALSA: synth: Save a few bytes of memory when registering a 'snd_emux'

snd_emux_register() calls pass a string literal as the 'name' parameter.

So kstrdup_const() can be used instead of kfree() to avoid a memory
allocation in such cases.

Signed-off-by: Christophe JAILLET <[email protected]>
---
include/sound/emux_synth.h | 2 +-
sound/synth/emux/emux.c | 4 ++--
2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/include/sound/emux_synth.h b/include/sound/emux_synth.h
index 1cc530434b97..3f7f365ed248 100644
--- a/include/sound/emux_synth.h
+++ b/include/sound/emux_synth.h
@@ -103,7 +103,7 @@ struct snd_emux {
int ports[SNDRV_EMUX_MAX_PORTS]; /* The ports for this device */
struct snd_emux_port *portptrs[SNDRV_EMUX_MAX_PORTS];
int used; /* use counter */
- char *name; /* name of the device (internal) */
+ const char *name; /* name of the device (internal) */
struct snd_rawmidi **vmidi;
struct timer_list tlist; /* for pending note-offs */
int timer_active;
diff --git a/sound/synth/emux/emux.c b/sound/synth/emux/emux.c
index 0006c3ddb51d..a82af9374852 100644
--- a/sound/synth/emux/emux.c
+++ b/sound/synth/emux/emux.c
@@ -85,7 +85,7 @@ int snd_emux_register(struct snd_emux *emu, struct snd_card *card, int index, ch
return -EINVAL;

emu->card = card;
- emu->name = kstrdup(name, GFP_KERNEL);
+ emu->name = kstrdup_const(name, GFP_KERNEL);
emu->voices = kcalloc(emu->max_voices, sizeof(struct snd_emux_voice),
GFP_KERNEL);
if (emu->name == NULL || emu->voices == NULL)
@@ -140,7 +140,7 @@ int snd_emux_free(struct snd_emux *emu)
snd_emux_delete_hwdep(emu);
snd_sf_free(emu->sflist);
kfree(emu->voices);
- kfree(emu->name);
+ kfree_const(emu->name);
kfree(emu);
return 0;
}
--
2.43.0

2024-01-22 12:16:41

by Takashi Iwai

Subject: Re: [PATCH] ALSA: synth: Save a few bytes of memory when registering a 'snd_emux'

On Sat, 20 Jan 2024 10:42:12 +0100,
Christophe JAILLET wrote:
>
> snd_emux_register() calls pass a string literal as the 'name' parameter.
>
> So kstrdup_const() can be used instead of kfree() to avoid a memory
> allocation in such cases.
>
> Signed-off-by: Christophe JAILLET <[email protected]>

Thanks, applied now.


Takashi