Replace selwakeup() with KNOTE() in audio(4).
KNOTE() can be used up to IPL_SCHED. IPL_SCHED is higher than IPL_AUDIO,
so the deferring through soft interrupts is no longer necessary.
In audio_detach(), the selwakeup() calls should not need replacing.
Any remaining kevent/poll/select waiters are woken up by
klist_invalidate().
OK?
Index: dev/audio.c
===================================================================
RCS file: src/sys/dev/audio.c,v
retrieving revision 1.199
diff -u -p -r1.199 audio.c
--- dev/audio.c 2 Jul 2022 08:50:41 -0000 1.199
+++ dev/audio.c 11 Jul 2022 15:14:09 -0000
@@ -20,6 +20,8 @@
#include <sys/ioctl.h>
#include <sys/conf.h>
#include <sys/kernel.h>
+#include <sys/event.h>
+#include <sys/mutex.h>
#include <sys/task.h>
#include <sys/vnode.h>
#include <sys/malloc.h>
@@ -75,8 +77,7 @@ struct audio_buf {
size_t used; /* bytes used in the FIFO */
size_t blksz; /* DMA block size */
unsigned int nblks; /* number of blocks */
- struct selinfo sel; /* to record & wakeup poll(2) */
- void *softintr; /* context to call selwakeup() */
+ struct klist klist; /* list of knotes */
unsigned int pos; /* bytes transferred */
unsigned int xrun; /* bytes lost by xruns */
int blocking; /* read/write blocking */
@@ -136,10 +137,9 @@ struct audio_softc {
int mix_nent; /* size of mixer state */
int mix_isopen; /* mixer open for reading */
int mix_blocking; /* read() blocking */
- struct selinfo mix_sel; /* wakeup poll(2) */
+ struct klist mix_klist; /* list of knotes */
struct mixer_ev *mix_evbuf; /* per mixer-control event */
struct mixer_ev *mix_pending; /* list of changed controls */
- void *mix_softintr; /* context to call selwakeup() */
#if NWSKBD > 0
struct wskbd_vol spkr, mic;
struct task wskbd_task;
@@ -153,6 +153,8 @@ int audio_activate(struct device *, int)
int audio_detach(struct device *, int);
void audio_pintr(void *);
void audio_rintr(void *);
+void audio_buf_wakeup(struct audio_buf *);
+void audio_mixer_wakeup(struct audio_softc *);
#if NWSKBD > 0
void wskbd_mixer_init(struct audio_softc *);
void wskbd_mixer_cb(void *);
@@ -275,53 +277,33 @@ audio_blksz_bytes(int mode,
}
void
-audio_mixer_wakeup(void *addr)
+audio_mixer_wakeup(struct audio_softc *sc)
{
- struct audio_softc *sc = addr;
+ MUTEX_ASSERT_LOCKED(&audio_lock);
if (sc->mix_blocking) {
wakeup(&sc->mix_blocking);
sc->mix_blocking = 0;
}
- /*
- * As long as selwakeup() grabs the KERNEL_LOCK() make sure it is
- * already held here to avoid lock ordering problems with `audio_lock'
- */
- KERNEL_ASSERT_LOCKED();
- mtx_enter(&audio_lock);
- selwakeup(&sc->mix_sel);
- mtx_leave(&audio_lock);
+ KNOTE(&sc->mix_klist, 0);
}
void
-audio_buf_wakeup(void *addr)
+audio_buf_wakeup(struct audio_buf *buf)
{
- struct audio_buf *buf = addr;
+ MUTEX_ASSERT_LOCKED(&audio_lock);
if (buf->blocking) {
wakeup(&buf->blocking);
buf->blocking = 0;
}
- /*
- * As long as selwakeup() grabs the KERNEL_LOCK() make sure it is
- * already held here to avoid lock ordering problems with `audio_lock'
- */
- KERNEL_ASSERT_LOCKED();
- mtx_enter(&audio_lock);
- selwakeup(&buf->sel);
- mtx_leave(&audio_lock);
+ KNOTE(&buf->klist, 0);
}
int
audio_buf_init(struct audio_softc *sc, struct audio_buf *buf, int dir)
{
- klist_init_mutex(&buf->sel.si_note, &audio_lock);
- buf->softintr = softintr_establish(IPL_SOFTAUDIO,
- audio_buf_wakeup, buf);
- if (buf->softintr == NULL) {
- printf("%s: can't establish softintr\n", DEVNAME(sc));
- goto bad;
- }
+ klist_init_mutex(&buf->klist, &audio_lock);
if (sc->ops->round_buffersize) {
buf->datalen = sc->ops->round_buffersize(sc->arg,
dir, AUDIO_BUFSZ);
@@ -333,13 +315,10 @@ audio_buf_init(struct audio_softc *sc, s
} else
buf->data = malloc(buf->datalen, M_DEVBUF, M_WAITOK);
if (buf->data == NULL) {
- softintr_disestablish(buf->softintr);
- goto bad;
+ klist_free(&buf->klist);
+ return ENOMEM;
}
return 0;
-bad:
- klist_free(&buf->sel.si_note);
- return ENOMEM;
}
void
@@ -349,8 +328,7 @@ audio_buf_done(struct audio_softc *sc, s
sc->ops->freem(sc->arg, buf->data, M_DEVBUF);
else
free(buf->data, M_DEVBUF, buf->datalen);
- softintr_disestablish(buf->softintr);
- klist_free(&buf->sel.si_note);
+ klist_free(&buf->klist);
}
/*
@@ -563,13 +541,7 @@ audio_pintr(void *addr)
if (sc->play.used < sc->play.len) {
DPRINTFN(1, "%s: play wakeup, chan = %d\n",
DEVNAME(sc), sc->play.blocking);
- /*
- * As long as selwakeup() needs to be protected by the
- * KERNEL_LOCK() we have to delay the wakeup to another
- * context to keep the interrupt context KERNEL_LOCK()
- * free.
- */
- softintr_schedule(sc->play.softintr);
+ audio_buf_wakeup(&sc->play);
}
}
@@ -646,13 +618,7 @@ audio_rintr(void *addr)
if (sc->rec.used > 0) {
DPRINTFN(1, "%s: rec wakeup, chan = %d\n",
DEVNAME(sc), sc->rec.blocking);
- /*
- * As long as selwakeup() needs to be protected by the
- * KERNEL_LOCK() we have to delay the wakeup to another
- * context to keep the interrupt context KERNEL_LOCK()
- * free.
- */
- softintr_schedule(sc->rec.softintr);
+ audio_buf_wakeup(&sc->rec);
}
}
@@ -1272,17 +1238,7 @@ audio_attach(struct device *parent, stru
return;
}
- klist_init_mutex(&sc->mix_sel.si_note, &audio_lock);
- sc->mix_softintr = softintr_establish(IPL_SOFTAUDIO,
- audio_mixer_wakeup, sc);
- if (sc->mix_softintr == NULL) {
- klist_free(&sc->mix_sel.si_note);
- audio_buf_done(sc, &sc->rec);
- audio_buf_done(sc, &sc->play);
- sc->ops = 0;
- printf("%s: can't establish softintr\n", DEVNAME(sc));
- return;
- }
+ klist_init_mutex(&sc->mix_klist, &audio_lock);
/* set defaults */
#if BYTE_ORDER == LITTLE_ENDIAN
@@ -1445,31 +1401,20 @@ audio_detach(struct device *self, int fl
if (sc->mode != 0) {
if (sc->active) {
wakeup(&sc->play.blocking);
- KERNEL_ASSERT_LOCKED();
- mtx_enter(&audio_lock);
wakeup(&sc->rec.blocking);
- selwakeup(&sc->play.sel);
- selwakeup(&sc->rec.sel);
- mtx_leave(&audio_lock);
audio_stop(sc);
}
sc->ops->close(sc->arg);
sc->mode = 0;
}
- if (sc->mix_isopen) {
+ if (sc->mix_isopen)
wakeup(&sc->mix_blocking);
- KERNEL_ASSERT_LOCKED();
- mtx_enter(&audio_lock);
- selwakeup(&sc->mix_sel);
- mtx_leave(&audio_lock);
- }
- klist_invalidate(&sc->play.sel.si_note);
- klist_invalidate(&sc->rec.sel.si_note);
- klist_invalidate(&sc->mix_sel.si_note);
+ klist_invalidate(&sc->play.klist);
+ klist_invalidate(&sc->rec.klist);
+ klist_invalidate(&sc->mix_klist);
/* free resources */
- softintr_disestablish(sc->mix_softintr);
- klist_free(&sc->mix_sel.si_note);
+ klist_free(&sc->mix_klist);
free(sc->mix_evbuf, M_DEVBUF, sc->mix_nent * sizeof(struct mixer_ev));
free(sc->mix_ents, M_DEVBUF, sc->mix_nent * sizeof(struct mixer_ctrl));
audio_buf_done(sc, &sc->play);
@@ -1875,7 +1820,7 @@ audio_event(struct audio_softc *sc, int
e->next = sc->mix_pending;
sc->mix_pending = e;
}
- softintr_schedule(sc->mix_softintr);
+ audio_mixer_wakeup(sc);
}
mtx_leave(&audio_lock);
}
@@ -2228,11 +2173,11 @@ audiokqfilter(dev_t dev, struct knote *k
case AUDIO_DEV_AUDIO:
switch (kn->kn_filter) {
case EVFILT_READ:
- klist = &sc->rec.sel.si_note;
+ klist = &sc->rec.klist;
kn->kn_fop = &audioread_filtops;
break;
case EVFILT_WRITE:
- klist = &sc->play.sel.si_note;
+ klist = &sc->play.klist;
kn->kn_fop = &audiowrite_filtops;
break;
default:
@@ -2243,7 +2188,7 @@ audiokqfilter(dev_t dev, struct knote *k
case AUDIO_DEV_AUDIOCTL:
switch (kn->kn_filter) {
case EVFILT_READ:
- klist = &sc->mix_sel.si_note;
+ klist = &sc->mix_klist;
kn->kn_fop = &audioctlread_filtops;
break;
default:
@@ -2265,7 +2210,7 @@ filt_audiordetach(struct knote *kn)
{
struct audio_softc *sc = kn->kn_hook;
- klist_remove(&sc->rec.sel.si_note, kn);
+ klist_remove(&sc->rec.klist, kn);
}
int
@@ -2283,7 +2228,7 @@ filt_audiowdetach(struct knote *kn)
{
struct audio_softc *sc = kn->kn_hook;
- klist_remove(&sc->play.sel.si_note, kn);
+ klist_remove(&sc->play.klist, kn);
}
int
@@ -2301,7 +2246,7 @@ filt_audioctlrdetach(struct knote *kn)
{
struct audio_softc *sc = kn->kn_hook;
- klist_remove(&sc->mix_sel.si_note, kn);
+ klist_remove(&sc->mix_klist, kn);
}
int
