| Message ID | 878s9m212i.wl-kuninori.morimoto.gx@renesas.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | ALSA: pcm: use bit field on snd_pcm | expand |
On Fri, 25 Dec 2020 01:21:43 +0100, Kuninori Morimoto wrote: > > > From: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com> > > 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@renesas.com> 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 >
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 */ }; /*