#include <sys/wait.h>
#include <sys/socket.h>
#include <sys/un.h>
+#include <sys/mman.h>
#include "pcm_local.h"
#include "../control/control_local.h"
key_t ipc_key; /* IPC key for semaphore and memory */
int semid; /* IPC global semaphore identification */
int shmid; /* IPC global shared memory identification */
+ int shmid_sum; /* IPC global sum ring buffer memory identification */
snd_pcm_dmix_share_t *shmptr; /* pointer to shared memory area */
+ signed int *sum_buffer; /* shared sum buffer */
snd_pcm_t *spcm; /* slave PCM handle */
snd_pcm_uframes_t appl_ptr;
snd_pcm_uframes_t hw_ptr;
shm_discard(dmix);
return -errno;
}
+ mlock(dmix->shmptr, sizeof(snd_pcm_dmix_share_t));
if (shmctl(dmix->shmid, IPC_STAT, &buf) < 0) {
shm_discard(dmix);
return -errno;
if (dmix->shmptr != (void *) -1 && shmdt(dmix->shmptr) < 0)
return -errno;
dmix->shmptr = (void *) -1;
- if (shmctl(dmix->shmid, IPC_STAT, &buf) < 0) {
- shm_discard(dmix);
+ if (shmctl(dmix->shmid, IPC_STAT, &buf) < 0)
return -errno;
- }
if (buf.shm_nattch == 0) { /* we're the last user, destroy the segment */
if (shmctl(dmix->shmid, IPC_RMID, NULL) < 0)
return -errno;
return ret;
}
+/*
+ * sum ring buffer shared memory area
+ */
+
+static int shm_sum_create_or_connect(snd_pcm_dmix_t *dmix)
+{
+ static int shm_sum_discard(snd_pcm_dmix_t *dmix);
+ size_t size;
+
+ size = dmix->shmptr->s.channels *
+ dmix->shmptr->s.buffer_size *
+ sizeof(signed int);
+ dmix->shmid_sum = shmget(dmix->ipc_key + 1, size, IPC_CREAT | 0666);
+ if (dmix->shmid_sum < 0)
+ return -errno;
+ dmix->sum_buffer = shmat(dmix->shmid_sum, 0, 0);
+ if (dmix->sum_buffer == (void *) -1) {
+ shm_sum_discard(dmix);
+ return -errno;
+ }
+ mlock(dmix->sum_buffer, size);
+ return 0;
+}
+
+static int shm_sum_discard(snd_pcm_dmix_t *dmix)
+{
+ struct shmid_ds buf;
+ int ret = 0;
+
+ if (dmix->shmid_sum < 0)
+ return -EINVAL;
+ if (dmix->sum_buffer != (void *) -1 && shmdt(dmix->sum_buffer) < 0)
+ return -errno;
+ dmix->sum_buffer = (void *) -1;
+ if (shmctl(dmix->shmid_sum, IPC_STAT, &buf) < 0)
+ return -errno;
+ if (buf.shm_nattch == 0) { /* we're the last user, destroy the segment */
+ if (shmctl(dmix->shmid_sum, IPC_RMID, NULL) < 0)
+ return -errno;
+ ret = 1;
+ }
+ dmix->shmid_sum = -1;
+ return ret;
+}
+
/*
* server side
*/
* FIXME: optimize it for different architectures
*/
+#ifdef __i386__
+#define ADD_AND_SATURATE
+static void mix_areas1(unsigned int size,
+ volatile signed short *dst, signed short *src,
+ volatile signed int *sum, unsigned int dst_step,
+ unsigned int src_step, unsigned int sum_step)
+{
+ /*
+ * ESI - src
+ * EDI - dst
+ * EBX - sum
+ * ECX - old sample
+ * EAX - sample / temporary
+ */
+ __asm__ __volatile__ (
+ "\n"
+
+ /*
+ * initialization, load ESI, EDI, EBX registers
+ */
+ "\tmovl %1, %%edi\n"
+ "\tmovl %2, %%esi\n"
+ "\tmovl %3, %%ebx\n"
+
+ /*
+ * while (size-- > 0) {
+ */
+ "\tcmp $0, %0\n"
+ "jz 6f\n"
+
+ "1:"
+
+ /*
+ * sample = *src;
+ * if (cmpxchg(*dst, 0, 1) == 0)
+ * sample -= *sum;
+ * xadd(*sum, sample);
+ */
+ "\tmovw $0, %%ax\n"
+ "\tmovw $1, %%cx\n"
+ "\tlock cmpxchgw %%cx, (%%edi)\n"
+ "\tmovswl (%%esi), %%ecx\n"
+ "\tjnz 2f\n"
+ "\tsubl (%%ebx), %%ecx\n"
+ "2:"
+ "\tlock addl %%ecx, (%%ebx)\n"
+
+ /*
+ * do {
+ * sample = old_sample = *sum;
+ * saturate(v);
+ * *dst = sample;
+ * } while (v != *sum);
+ */
+
+ "3:"
+ "\tmovl (%%ebx), %%ecx\n"
+ "\tcmpl $0x7fff,%%ecx\n"
+ "\tjg 4f\n"
+ "\tcmpl $-0x8000,%%ecx\n"
+ "\tjl 5f\n"
+ "\tmovw %%cx, (%%edi)\n"
+ "\tcmpl %%ecx, (%%ebx)\n"
+ "\tjnz 3b\n"
+
+ /*
+ * while (size-- > 0)
+ */
+ "\tadd %4, %%edi\n"
+ "\tadd %5, %%esi\n"
+ "\tadd %6, %%ebx\n"
+ "\tdecl %0\n"
+ "\tjnz 1b\n"
+ "\tjmp 6f\n"
+
+ /*
+ * sample > 0x7fff
+ */
+
+ "4:"
+ "\tmovw $0x7fff, %%ax\n"
+ "\tmovw (%%edi), %%ax\n"
+ "\tcmpl %%ecx,(%%ebx)\n"
+ "\tjnz 3b\n"
+ "\tadd %4, %%edi\n"
+ "\tadd %5, %%esi\n"
+ "\tadd %6, %%ebx\n"
+ "\tdecl %0\n"
+ "\tjnz 1b\n"
+ "\tjmp 6f\n"
+
+ /*
+ * sample < -0x8000
+ */
+
+ "5:"
+ "\tmovw $-0x8000, %%ax\n"
+ "\tmovw (%%edi), %%ax\n"
+ "\tcmpl %%ecx,(%%ebx)\n"
+ "\tjnz 3b\n"
+ "\tadd %4, %%edi\n"
+ "\tadd %5, %%esi\n"
+ "\tadd %6, %%ebx\n"
+ "\tdecl %0\n"
+ "\tjnz 1b\n"
+ // "\tjmp 6f\n"
+
+ "6:"
+
+ : /* no output regs */
+ : "m" (size), "m" (dst), "m" (src), "m" (sum), "m" (dst_step), "m" (src_step), "m" (sum_step)
+ : "esi", "edi", "ecx", "ebx", "eax"
+ );
+}
+#endif
+
+#ifndef ADD_AND_SATURATE
+#warning Please, recode add_and_saturate routine to your architecture...
+static void mix_areas1(unsigned int size,
+ volatile signed short *dst, signed short *src,
+ volatile signed int *sum, unsigned int dst_step,
+ unsigned int src_step, unsigned int sum_step)
+{
+ register signed int sample, old_sample;
+
+ while (size-- > 0) {
+ sample = *src;
+ if (*dst == 0)
+ sample -= *sum;
+ *sum += sample;
+ do {
+ old_sample = *sum;
+ if (old_sample > 0x7fff)
+ sample = 0x7fff;
+ else if (old_sample < -0x8000)
+ sample = -0x8000;
+ else
+ sample = old_sample;
+ *dst = sample;
+ } while (*sum != old_sample);
+ ((char *)src) += dst_step;
+ ((char *)dst) += src_step;
+ ((char *)sum) += sum_step;
+ }
+}
+#endif
+
static void mix_areas(const snd_pcm_channel_area_t *src_areas,
const snd_pcm_channel_area_t *dst_areas,
unsigned int channels,
snd_pcm_uframes_t src_ofs,
snd_pcm_uframes_t dst_ofs,
- snd_pcm_uframes_t size)
+ snd_pcm_uframes_t size,
+ void *sum_buffer)
{
- register signed int sample;
- signed short *src, *dst;
+ signed short *src;
+ volatile signed short *dst;
+ volatile signed int *sum;
unsigned int src_step, dst_step;
- unsigned int chn, count;
+ unsigned int chn;
+ int interleaved = 1;
+ for (chn = 1; chn < channels; chn++) {
+ if (dst_areas[chn-1].addr != dst_areas[chn].addr) {
+ interleaved = 0;
+ break;
+ }
+ }
+ for (chn = 0; chn < channels; chn++) {
+ if (dst_areas[chn].first != sizeof(signed short) * chn * 8 ||
+ dst_areas[chn].step != channels * sizeof(signed short) * 8) {
+ interleaved = 0;
+ break;
+ }
+ }
+ if (interleaved) {
+ /*
+ * process the area in one loop
+ * it optimizes the memory accesses for this case
+ */
+ mix_areas1(size * channels,
+ ((signed short *)dst_areas[0].addr) + (dst_ofs * channels),
+ ((signed short *)src_areas[0].addr) + (src_ofs * channels),
+ ((signed int *)sum_buffer) + (dst_ofs * channels),
+ sizeof(signed short),
+ sizeof(signed short),
+ sizeof(signed int));
+ return;
+ }
for (chn = 0; chn < channels; chn++) {
src_step = src_areas[chn].step / 8;
dst_step = dst_areas[chn].step / 8;
src = (signed short *)(((char *)src_areas[chn].addr + src_areas[chn].first / 8) + (src_ofs * src_step));
dst = (signed short *)(((char *)dst_areas[chn].addr + dst_areas[chn].first / 8) + (dst_ofs * dst_step));
- count = 0;
- while (count++ < size) {
- /* FIXME: it's pretty ugly, because the other process might modify our value between
- read / write session - especially on MP machines */
- sample = *dst + *src;
- if (sample > 0x7fff)
- sample = 0x7fff;
- if (sample < -0x8000)
- sample = -0x8000;
- *dst = sample;
- ((char *)src) += src_step;
- ((char *)dst) += dst_step;
- }
+ sum = (signed int *)sum_buffer + channels * dst_ofs + chn;
+ mix_areas1(size, dst, src, sum, dst_step, src_step, channels * sizeof(signed int));
}
}
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;
- mix_areas(src_areas, dst_areas, pcm->channels, appl_ptr, slave_appl_ptr, transfer);
+ mix_areas(src_areas, dst_areas, pcm->channels, appl_ptr, slave_appl_ptr, transfer, dmix->sum_buffer);
slave_appl_ptr += transfer;
slave_appl_ptr %= dmix->shmptr->s.buffer_size;
appl_ptr += transfer;
server_discard(dmix);
if (dmix->client)
client_discard(dmix);
+ shm_sum_discard(dmix);
if (shm_discard(dmix) > 0) {
if (semaphore_discard(dmix) < 0)
semaphore_up(dmix, DMIX_IPC_SEM_CLIENT);
dmix->spcm = spcm;
}
+ ret = shm_sum_create_or_connect(dmix);
+ if (ret < 0) {
+ SNDERR("unabel to initialize sum ring buffer\n");
+ goto _err;
+ }
+
ret = snd_pcm_dmix_initialize_poll_fd(dmix);
if (ret < 0) {
SNDERR("unable to initialize poll_fd\n");
client_discard(dmix);
if (spcm)
snd_pcm_close(spcm);
+ if (dmix->shmid_sum >= 0)
+ shm_sum_discard(dmix);
if (dmix->shmid >= 0) {
if (shm_discard(dmix) > 0) {
if (dmix->semid >= 0) {
git://git.alsa-project.org / alsa-lib.git / commitdiff