On Fri, 25 Dec 2020 01:21:43 +0100,
Kuninori Morimoto wrote:
>
>
> From: Kuninori Morimoto <kuninori.morimoto.gx@xxxxxxxxxxx>
>
> snd_pcm's internal, nonatomic, no_device_suspend are defined as bool.
> But we can reduce struct size if we use bit field for these.
> This patch converts these.
>
> Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@xxxxxxxxxxx>
Practically seen, this doesn't reduce the struct size at all, as bool
is usually a byte type. And, a byte access is even better from the
performance and concurrency POV.
So, unless there is any better reason, I don't think it worth to
switch to bit fields.
thanks,
Takashi
> ---
> include/sound/pcm.h | 7 ++++---
> 1 file changed, 4 insertions(+), 3 deletions(-)
>
> diff --git a/include/sound/pcm.h b/include/sound/pcm.h
> index 2336bf9243e1..e836741d2708 100644
> --- a/include/sound/pcm.h
> +++ b/include/sound/pcm.h
> @@ -520,12 +520,13 @@ struct snd_pcm {
> wait_queue_head_t open_wait;
> void *private_data;
> void (*private_free) (struct snd_pcm *pcm);
> - bool internal; /* pcm is for internal use only */
> - bool nonatomic; /* whole PCM operations are in non-atomic context */
> - bool no_device_suspend; /* don't invoke device PM suspend */
> #if IS_ENABLED(CONFIG_SND_PCM_OSS)
> struct snd_pcm_oss oss;
> #endif
> + /* bit field */
> + unsigned int internal:1; /* pcm is for internal use only */
> + unsigned int nonatomic:1; /* whole PCM operations are in non-atomic context */
> + unsigned int no_device_suspend:1; /* don't invoke device PM suspend */
> };
>
> /*
> --
> 2.25.1
>
