[pulseaudio-commits] r1496 - /branches/lennart/src/pulsecore/asyncq.c
svnmailer-noreply at 0pointer.de
svnmailer-noreply at 0pointer.de
Sun Jun 24 09:15:57 PDT 2007
Author: lennart
Date: Sun Jun 24 18:15:56 2007
New Revision: 1496
URL: http://0pointer.de/cgi-bin/viewcvs.cgi?rev=3D1496&root=3Dpulseaudio&vi=
ew=3Drev
Log:
rework the logic of pa_asyncq
Modified:
branches/lennart/src/pulsecore/asyncq.c
Modified: branches/lennart/src/pulsecore/asyncq.c
URL: http://0pointer.de/cgi-bin/viewcvs.cgi/branches/lennart/src/pulsecore/=
asyncq.c?rev=3D1496&root=3Dpulseaudio&r1=3D1495&r2=3D1496&view=3Ddiff
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D
--- branches/lennart/src/pulsecore/asyncq.c (original)
+++ branches/lennart/src/pulsecore/asyncq.c Sun Jun 24 18:15:56 2007
@@ -52,9 +52,10 @@
unsigned size;
unsigned read_idx;
unsigned write_idx;
- pa_atomic_t read_waiting, n_read;
- pa_atomic_t write_waiting, n_written;
+ pa_atomic_t read_waiting; /* a bool */
+ pa_atomic_t write_waiting; /* a bool */
int read_fds[2], write_fds[2];
+ pa_atomic_t in_read_fifo, in_write_fifo;
};
=
#define PA_ASYNCQ_CELLS(x) ((pa_atomic_ptr_t*) ((uint8_t*) (x) + PA_ALIGN(=
sizeof(struct pa_asyncq))))
@@ -80,8 +81,8 @@
l->size =3D size;
pa_atomic_store(&l->read_waiting, 0);
pa_atomic_store(&l->write_waiting, 0);
- pa_atomic_store(&l->n_written, 0);
- pa_atomic_store(&l->n_read, 0);
+ pa_atomic_store(&l->in_read_fifo, 0);
+ pa_atomic_store(&l->in_write_fifo, 0);
=
if (pipe(l->read_fds) < 0) {
pa_xfree(l);
@@ -133,68 +134,79 @@
=
if (!pa_atomic_ptr_cmpxchg(&cells[idx], NULL, p)) {
=
- if (!wait) {
- /* Let's empty the FIFO from old notifications, before we retu=
rn */
- =
- while (pa_atomic_load(&l->n_read) > 0) {
- ssize_t r;
- int x[20];
- =
- errno =3D 0;
- if ((r =3D read(l->write_fds[0], x, sizeof(x))) < 0 && err=
no !=3D EINTR)
- return -1;
-
- pa_assert(r !=3D 0);
- =
- if (r > 0)
- if (pa_atomic_sub(&l->n_read, r) <=3D r)
- break;
- }
- =
- return -1;
- }
-
- /* First try failed. Let's wait for changes. */
-
- _Y;
-
- pa_atomic_inc(&l->write_waiting);
-
- for (;;) {
- char x[20];
+ /* Let's empty the FIFO from old notifications, before we return */
+ =
+ while (pa_atomic_load(&l->in_write_fifo) > 0) {
ssize_t r;
-
- _Y;
-
- if (pa_atomic_ptr_cmpxchg(&cells[idx], NULL, p))
- break;
-
- _Y;
-
- if ((r =3D read(l->write_fds[0], x, sizeof(x))) < 0 && errno !=
=3D EINTR) {
- pa_atomic_dec(&l->write_waiting);
+ int x[20];
+
+ if ((r =3D read(l->write_fds[0], x, sizeof(x))) < 0) {
+
+ if (errno =3D=3D EINTR)
+ continue;
+ =
return -1;
}
=
- pa_assert(r !=3D 0);
-
- if (r > 0)
- pa_atomic_sub(&l->n_read, r);
- }
-
- _Y;
-
- pa_atomic_dec(&l->write_waiting);
+ pa_assert(r > 0);
+ =
+ if (pa_atomic_sub(&l->in_write_fifo, r) <=3D r)
+ break;
+
+ }
+
+ /* Now let's make sure that we didn't lose any events */
+ if (!pa_atomic_ptr_cmpxchg(&cells[idx], NULL, p)) {
+
+ if (!wait)
+ return -1;
+
+ /* Let's wait for changes. */
+
+ _Y;
+
+ pa_assert_se(pa_atomic_cmpxchg(&l->write_waiting, 0, 1));
+
+ for (;;) {
+ char x[20];
+ ssize_t r;
+ =
+ _Y;
+ =
+ if (pa_atomic_ptr_cmpxchg(&cells[idx], NULL, p))
+ break;
+ =
+ _Y;
+
+ if ((r =3D read(l->write_fds[0], x, sizeof(x))) < 0) {
+
+ if (errno =3D=3D EINTR)
+ continue;
+ =
+ pa_assert_se(pa_atomic_cmpxchg(&l->write_waiting, 1, 0=
));
+ return -1;
+ }
+
+ pa_assert(r > 0);
+ pa_atomic_sub(&l->in_write_fifo, r);
+ }
+ =
+ _Y;
+ =
+ pa_assert_se(pa_atomic_cmpxchg(&l->write_waiting, 1, 0));
+ }
}
=
_Y;
l->write_idx++;
=
- if (pa_atomic_load(&l->read_waiting)) {
+ if (pa_atomic_load(&l->read_waiting) > 0) {
char x =3D 'x';
_Y;
- if (write(l->read_fds[1], &x, sizeof(x)) > 0)
- pa_atomic_inc(&l->n_written);
+ if (write(l->read_fds[1], &x, sizeof(x)) > 0) {
+ pa_atomic_inc(&l->in_read_fifo);
+/* pa_log("increasing %p by 1", l); */
+ }
}
=
return 0;
@@ -206,7 +218,7 @@
pa_atomic_ptr_t *cells;
=
pa_assert(l);
-
+ =
cells =3D PA_ASYNCQ_CELLS(l);
=
_Y;
@@ -214,59 +226,74 @@
=
if (!(ret =3D pa_atomic_ptr_load(&cells[idx]))) {
=
- /* First try failed. Let's wait for changes. */
-
- if (!wait) {
- /* Let's empty the FIFO from old notifications, before we retu=
rn */
- =
- while (pa_atomic_load(&l->n_written) > 0) {
- ssize_t r;
- int x[20];
- =
- errno =3D 0;
- if ((r =3D read(l->read_fds[0], x, sizeof(x))) < 0 && errn=
o !=3D EINTR)
- return NULL;
-
- pa_assert(r !=3D 0);
- =
- if (r > 0)
- if (pa_atomic_sub(&l->n_written, r) <=3D r)
- break;
- }
- =
- return NULL;
- }
-
- _Y;
-
- pa_atomic_inc(&l->read_waiting);
-
- for (;;) {
- char x[20];
+/* pa_log("pop failed wait=3D%i", wait); */
+
+ /* Hmm, nothing, here, so let's drop all queued events. */
+ while (pa_atomic_load(&l->in_read_fifo) > 0) {
ssize_t r;
-
- _Y;
-
- if ((ret =3D pa_atomic_ptr_load(&cells[idx])))
- break;
-
- _Y;
-
- if ((r =3D read(l->read_fds[0], x, sizeof(x))) < 0 && errno !=
=3D EINTR) {
- pa_atomic_dec(&l->read_waiting);
+ int x[20];
+ =
+ if ((r =3D read(l->read_fds[0], x, sizeof(x))) < 0) {
+ =
+ if (errno =3D=3D EINTR)
+ continue;
+ =
return NULL;
}
=
- pa_assert(r !=3D 0);
-
- if (r > 0)
- pa_atomic_sub(&l->n_written, r);
- }
-
- _Y;
-
- pa_atomic_dec(&l->read_waiting);
- }
+ pa_assert(r > 0);
+
+/* pa_log("decreasing %p by %i", l, r); */
+ =
+ if (pa_atomic_sub(&l->in_read_fifo, r) <=3D r)
+ break;
+ }
+
+ /* Now let's make sure that we didn't lose any events */
+ if (!(ret =3D pa_atomic_ptr_load(&cells[idx]))) {
+
+ if (!wait)
+ return NULL;
+
+ /* Let's wait for changes. */
+ =
+ _Y;
+ =
+ pa_assert_se(pa_atomic_cmpxchg(&l->read_waiting, 0, 1));
+ =
+ for (;;) {
+ char x[20];
+ ssize_t r;
+ =
+ _Y;
+ =
+ if ((ret =3D pa_atomic_ptr_load(&cells[idx])))
+ break;
+ =
+ _Y;
+ =
+ if ((r =3D read(l->read_fds[0], x, sizeof(x))) < 0) {
+
+ if (errno =3D=3D EINTR)
+ continue;
+ =
+ pa_assert_se(pa_atomic_cmpxchg(&l->read_waiting, 1, 0)=
);
+ return NULL;
+ }
+
+/* pa_log("decreasing %p by %i", l, r); */
+ =
+ pa_assert(r > 0);
+ pa_atomic_sub(&l->in_read_fifo, r);
+ }
+
+ _Y;
+
+ pa_assert_se(pa_atomic_cmpxchg(&l->read_waiting, 1, 0));
+ }
+ }
+
+ pa_assert(ret);
=
/* Guaranteed if we only have a single reader */
pa_assert_se(pa_atomic_ptr_cmpxchg(&cells[idx], ret, NULL));
@@ -274,11 +301,11 @@
_Y;
l->read_idx++;
=
- if (pa_atomic_load(&l->write_waiting)) {
+ if (pa_atomic_load(&l->write_waiting) > 0) {
char x =3D 'x';
_Y;
if (write(l->write_fds[1], &x, sizeof(x)) >=3D 0)
- pa_atomic_inc(&l->n_read);
+ pa_atomic_inc(&l->in_write_fifo);
}
=
return ret;
@@ -301,13 +328,13 @@
_Y;
idx =3D reduce(l, l->read_idx);
=
- if (pa_atomic_ptr_load(&cells[idx]))
+ if (pa_atomic_ptr_load(&cells[idx]) || pa_atomic_load(&l->in_read_fifo=
) > 0)
return -1;
=
- pa_atomic_inc(&l->read_waiting);
-
- if (pa_atomic_ptr_load(&cells[idx])) {
- pa_atomic_dec(&l->read_waiting);
+ pa_assert_se(pa_atomic_cmpxchg(&l->read_waiting, 0, 1));
+
+ if (pa_atomic_ptr_load(&cells[idx]) || pa_atomic_load(&l->in_read_fifo=
) > 0) {
+ pa_assert_se(pa_atomic_cmpxchg(&l->read_waiting, 1, 0));
return -1;
}
=
@@ -317,7 +344,5 @@
void pa_asyncq_after_poll(pa_asyncq *l) {
pa_assert(l);
=
- pa_assert(pa_atomic_load(&l->read_waiting) > 0);
-
- pa_atomic_dec(&l->read_waiting);
-}
+ pa_assert_se(pa_atomic_cmpxchg(&l->read_waiting, 1, 0));
+}
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