pcm: dmix: Fix semaphore usage with lockless operation

As Maarten Baert recently reported, the current dmix code applies the
semaphore unnecessarily around mixing streams even when the lockless
mix operation is used on x86.  This was rather introduced mistakenly
at the commit 267d7c7281 ("Add support of little-endian on
i386/x86_64 dmix") where the generic dmix code was included on x86,
too.

For achieving the original performance back, this patch changes the
semaphore handling to be checked at run time instead of statically at
compile time.

Reviewed-by: Jaroslav Kysela <perex@perex.cz>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
This commit is contained in:
Takashi Iwai 2020-06-19 18:40:46 +02:00
parent 4759865c86
commit d824b461ae
5 changed files with 15 additions and 8 deletions

View file

@ -186,6 +186,7 @@ struct snd_pcm_direct {
mix_areas_32_t *remix_areas_32;
mix_areas_24_t *remix_areas_24;
mix_areas_u8_t *remix_areas_u8;
unsigned int use_sem;
} dmix;
struct {
unsigned long long chn_mask;