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<atlka@pg.gda.pl>

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- shm memory patch
- optimized a bit sample mixing routines in c and x_86 asm
This commit is contained in:
Jaroslav Kysela 2004-01-24 16:34:35 +00:00
parent 0f88788f8b
commit b798d89c0f
5 changed files with 86 additions and 83 deletions
Download patch file Download diff file Expand all files Collapse all files

30
src/pcm/pcm_dmix.c
View file

@ -59,14 +59,26 @@ const char *_snd_module_pcm_dmix = "";
static int shm_sum_create_or_connect(snd_pcm_direct_t *dmix)
{
static int shm_sum_discard(snd_pcm_direct_t *dmix);
struct shmid_ds buf;
int tmpid, err;
size_t size;
size = dmix->shmptr->s.channels *
dmix->shmptr->s.buffer_size *
sizeof(signed int);
retryshm:
dmix->u.dmix.shmid_sum = shmget(dmix->ipc_key + 1, size, IPC_CREAT | 0666);
if (dmix->u.dmix.shmid_sum < 0)
return -errno;
err = -errno;
if (dmix->u.dmix.shmid_sum < 0){
if (errno == EINVAL)
if ((tmpid = shmget(dmix->ipc_key + 1, 0, 0666)) != -1)
if (!shmctl(tmpid, IPC_STAT, &buf))
if (!buf.shm_nattch)
/* no users so destroy the segment */
if (!shmctl(tmpid, IPC_RMID, NULL))
goto retryshm;
return err;
}
dmix->u.dmix.sum_buffer = shmat(dmix->u.dmix.shmid_sum, 0, 0);
if (dmix->u.dmix.sum_buffer == (void *) -1) {
shm_sum_discard(dmix);
@ -214,7 +226,7 @@ static void mix_areas1(unsigned int size,
{
register signed int sample, old_sample;
while (size-- > 0) {
for (;;) {
sample = *src;
old_sample = *sum;
if (*dst == 0)
@ -230,6 +242,8 @@ static void mix_areas1(unsigned int size,
sample = old_sample;
*dst = sample;
} while (*sum != old_sample);
if (!--size)
return;
((char *)src) += src_step;
((char *)dst) += dst_step;
((char *)sum) += sum_step;
@ -244,7 +258,7 @@ static void mix_areas2(unsigned int size,
{
register signed int sample, old_sample;
while (size-- > 0) {
for (;;) {
sample = *src / 256;
old_sample = *sum;
if (*dst == 0)
@ -260,6 +274,8 @@ static void mix_areas2(unsigned int size,
sample = old_sample * 256;
*dst = sample;
} while (*sum != old_sample);
if (!--size)
return;
((char *)src) += src_step;
((char *)dst) += dst_step;
((char *)sum) += sum_step;
@ -366,9 +382,11 @@ static void snd_pcm_dmix_sync_area(snd_pcm_t *pcm, snd_pcm_uframes_t size)
dmix->slave_appl_ptr %= dmix->shmptr->s.boundary;
while (size > 0) {
transfer = appl_ptr + size > pcm->buffer_size ? pcm->buffer_size - appl_ptr : size;
transfer = slave_appl_ptr + transfer > dmix->shmptr->s.buffer_size ? dmix->shmptr->s.buffer_size - slave_appl_ptr : transfer;
size -= transfer;
if ((transfer = slave_appl_ptr + transfer > dmix->shmptr->s.buffer_size ? dmix->shmptr->s.buffer_size - slave_appl_ptr : transfer))
mix_areas(dmix, src_areas, dst_areas, appl_ptr, slave_appl_ptr, transfer);
if (transfer >= size)
return;
size -= transfer;
slave_appl_ptr += transfer;
slave_appl_ptr %= dmix->shmptr->s.buffer_size;
appl_ptr += transfer;