mirrors/alsa-lib
1
0
Fork 0
mirror of https://github.com/alsa-project/alsa-lib.git synced 2025-12-16 08:56:42 -05:00
Code Issues Projects Releases Packages Wiki Activity Actions

Moved some prototypes from src/pcm/pcm_plugin.h to include/pcm_plugin.h.

Browse source 
Merged src/pcm/atomic.h to include/iatomic.h.
Added initial description of hw and hooks plugins.
This commit is contained in:
Jaroslav Kysela 2002-01-12 10:52:42 +00:00
parent b36ad628f7
commit 8c1887d7af
18 changed files with 442 additions and 159 deletions
Download patch file Download diff file Expand all files Collapse all files

74
include/iatomic.h
View file

@ -1,5 +1,5 @@
#ifndef __ALSA_IATOMIC__
#define __ALSA_IATOMIC__
#ifndef __ALSA_IATOMIC_H
#define __ALSA_IATOMIC_H
#ifdef __i386__
@ -1059,4 +1059,72 @@ typedef struct { volatile int counter; } atomic_t;
#endif /* IATOMIC_DEFINED */
#endif /* __ALSA_IATOMIC__ */
/*
* Atomic read/write
* Copyright (c) 2001 by Abramo Bagnara <abramo@alsa-project.org>
*/
/* Max number of times we must spin on a spinlock calling sched_yield().
After MAX_SPIN_COUNT iterations, we put the calling thread to sleep. */
#ifndef MAX_SPIN_COUNT
#define MAX_SPIN_COUNT 50
#endif
/* Duration of sleep (in nanoseconds) when we can't acquire a spinlock
after MAX_SPIN_COUNT iterations of sched_yield().
This MUST BE > 2ms.
(Otherwise the kernel does busy-waiting for realtime threads,
giving other threads no chance to run.) */
#ifndef SPIN_SLEEP_DURATION
#define SPIN_SLEEP_DURATION 2000001
#endif
typedef struct {
unsigned int begin, end;
} snd_atomic_write_t;
typedef struct {
volatile const snd_atomic_write_t *write;
unsigned int end;
} snd_atomic_read_t;
void snd_atomic_read_wait(snd_atomic_read_t *t);
static inline void snd_atomic_write_init(snd_atomic_write_t *w)
{
w->begin = 0;
w->end = 0;
}
static inline void snd_atomic_write_begin(snd_atomic_write_t *w)
{
w->begin++;
wmb();
}
static inline void snd_atomic_write_end(snd_atomic_write_t *w)
{
wmb();
w->end++;
}
static inline void snd_atomic_read_init(snd_atomic_read_t *r, snd_atomic_write_t *w)
{
r->write = w;
}
static inline void snd_atomic_read_begin(snd_atomic_read_t *r)
{
r->end = r->write->end;
rmb();
}
static inline int snd_atomic_read_ok(snd_atomic_read_t *r)
{
rmb();
return r->end == r->write->begin;
}
#endif /* __ALSA_IATOMIC_H */