From 3c5d2f52adeb26b21fdf910d8e6cb330ebae79e5 Mon Sep 17 00:00:00 2001 From: Taylor R Campbell Date: Mon, 14 Jun 2021 00:32:31 +0000 Subject: [PATCH] pad(4): Fix some locking. - No need for sc_cond_lock. - Issue cv_broadcast under the correct lock. - Use callout_halt, not haphazard callout_stop. - IPL_SOFTCLOCK for a mutex taken from a callout. --- sys/dev/pad/pad.c | 57 +++++++++++++++----------------------------- sys/dev/pad/padvar.h | 2 -- 2 files changed, 19 insertions(+), 40 deletions(-) diff --git a/sys/dev/pad/pad.c b/sys/dev/pad/pad.c index 4e603cbc8607..673e02a51f87 100644 --- a/sys/dev/pad/pad.c +++ b/sys/dev/pad/pad.c @@ -223,13 +223,12 @@ pad_attach(device_t parent, device_t self, void *opaque) aprint_normal_dev(self, "outputs: 44100Hz, 16-bit, stereo\n"); sc->sc_dev = self; - sc->sc_dying = false; cv_init(&sc->sc_condvar, device_xname(sc->sc_dev)); - mutex_init(&sc->sc_cond_lock, MUTEX_DEFAULT, IPL_NONE); mutex_init(&sc->sc_lock, MUTEX_DEFAULT, IPL_NONE); - mutex_init(&sc->sc_intr_lock, MUTEX_DEFAULT, IPL_NONE); - callout_init(&sc->sc_pcallout, 0/*XXX?*/); + mutex_init(&sc->sc_intr_lock, MUTEX_DEFAULT, IPL_SOFTCLOCK); + callout_init(&sc->sc_pcallout, CALLOUT_MPSAFE); + callout_setfunc(&sc->sc_pcallout, pad_done_output, sc); sc->sc_swvol = 255; sc->sc_buflen = 0; @@ -258,7 +257,6 @@ pad_detach(device_t self, int flags) pmf_device_deregister(sc->sc_dev); - mutex_destroy(&sc->sc_cond_lock); mutex_destroy(&sc->sc_lock); mutex_destroy(&sc->sc_intr_lock); cv_destroy(&sc->sc_condvar); @@ -514,12 +512,12 @@ pad_read(struct pad_softc *sc, off_t *offp, struct uio *uio, kauth_cred_t cred, err = 0; DPRINTF("%s: resid=%zu\n", __func__, uio->uio_resid); while (uio->uio_resid > 0 && !err) { - mutex_enter(&sc->sc_cond_lock); + mutex_enter(&sc->sc_intr_lock); if (sc->sc_buflen == 0) { DPRINTF("%s: wait\n", __func__); - err = cv_wait_sig(&sc->sc_condvar, &sc->sc_cond_lock); + err = cv_wait_sig(&sc->sc_condvar, &sc->sc_intr_lock); DPRINTF("%s: wake up %d\n", __func__, err); - mutex_exit(&sc->sc_cond_lock); + mutex_exit(&sc->sc_intr_lock); if (err) { if (err == ERESTART) err = EINTR; @@ -532,7 +530,7 @@ pad_read(struct pad_softc *sc, off_t *offp, struct uio *uio, kauth_cred_t cred, len = uimin(uio->uio_resid, sc->sc_buflen); err = pad_get_block(sc, &pb, len); - mutex_exit(&sc->sc_cond_lock); + mutex_exit(&sc->sc_intr_lock); if (err) break; DPRINTF("%s: move %d\n", __func__, pb.pb_len); @@ -562,9 +560,7 @@ pad_set_format(void *opaque, int setmode, const audio_params_t *play, const audio_params_t *rec, audio_filter_reg_t *pfil, audio_filter_reg_t *rfil) { - struct pad_softc *sc; - - sc = (struct pad_softc *)opaque; + struct pad_softc *sc = opaque; KASSERT(mutex_owned(&sc->sc_lock)); @@ -579,12 +575,10 @@ static int pad_start_output(void *opaque, void *block, int blksize, void (*intr)(void *), void *intrarg) { - struct pad_softc *sc; + struct pad_softc *sc = opaque; int err; int ms; - sc = (struct pad_softc *)opaque; - KASSERT(mutex_owned(&sc->sc_intr_lock)); sc->sc_intr = intr; @@ -592,14 +586,12 @@ pad_start_output(void *opaque, void *block, int blksize, sc->sc_blksize = blksize; DPRINTF("%s: blksize=%d\n", __func__, blksize); - mutex_enter(&sc->sc_cond_lock); err = pad_add_block(sc, block, blksize); - mutex_exit(&sc->sc_cond_lock); cv_broadcast(&sc->sc_condvar); ms = blksize * 1000 / PADCHAN / (PADPREC / NBBY) / PADFREQ; DPRINTF("%s: callout ms=%d\n", __func__, ms); - callout_reset(&sc->sc_pcallout, mstohz(ms), pad_done_output, sc); + callout_schedule(&sc->sc_pcallout, mstohz(ms)); return err; } @@ -607,19 +599,18 @@ pad_start_output(void *opaque, void *block, int blksize, static int pad_halt_output(void *opaque) { - struct pad_softc *sc; - - sc = (struct pad_softc *)opaque; + struct pad_softc *sc = opaque; DPRINTF("%s\n", __func__); KASSERT(mutex_owned(&sc->sc_intr_lock)); - cv_broadcast(&sc->sc_condvar); - callout_stop(&sc->sc_pcallout); + callout_halt(&sc->sc_pcallout, &sc->sc_intr_lock); + sc->sc_intr = NULL; sc->sc_intrarg = NULL; sc->sc_buflen = 0; sc->sc_rpos = sc->sc_wpos = 0; + cv_broadcast(&sc->sc_condvar); return 0; } @@ -627,11 +618,9 @@ pad_halt_output(void *opaque) static void pad_done_output(void *arg) { - struct pad_softc *sc; + struct pad_softc *sc = arg; DPRINTF("%s\n", __func__); - sc = (struct pad_softc *)arg; - callout_stop(&sc->sc_pcallout); mutex_enter(&sc->sc_intr_lock); (*sc->sc_intr)(sc->sc_intrarg); @@ -652,9 +641,7 @@ pad_getdev(void *opaque, struct audio_device *ret) static int pad_set_port(void *opaque, mixer_ctrl_t *mc) { - struct pad_softc *sc; - - sc = (struct pad_softc *)opaque; + struct pad_softc *sc = opaque; KASSERT(mutex_owned(&sc->sc_lock)); @@ -673,9 +660,7 @@ pad_set_port(void *opaque, mixer_ctrl_t *mc) static int pad_get_port(void *opaque, mixer_ctrl_t *mc) { - struct pad_softc *sc; - - sc = (struct pad_softc *)opaque; + struct pad_softc *sc = opaque; KASSERT(mutex_owned(&sc->sc_lock)); @@ -694,9 +679,7 @@ pad_get_port(void *opaque, mixer_ctrl_t *mc) static int pad_query_devinfo(void *opaque, mixer_devinfo_t *di) { - struct pad_softc *sc __diagused; - - sc = (struct pad_softc *)opaque; + struct pad_softc *sc __diagused = opaque; KASSERT(mutex_owned(&sc->sc_lock)); @@ -744,9 +727,7 @@ pad_get_props(void *opaque) static void pad_get_locks(void *opaque, kmutex_t **intr, kmutex_t **thread) { - struct pad_softc *sc; - - sc = (struct pad_softc *)opaque; + struct pad_softc *sc = opaque; *intr = &sc->sc_intr_lock; *thread = &sc->sc_lock; diff --git a/sys/dev/pad/padvar.h b/sys/dev/pad/padvar.h index 11c8bcc6a163..22409cf812fb 100644 --- a/sys/dev/pad/padvar.h +++ b/sys/dev/pad/padvar.h @@ -39,9 +39,7 @@ struct pad_softc { kcondvar_t sc_condvar; kmutex_t sc_lock; kmutex_t sc_intr_lock; - kmutex_t sc_cond_lock; callout_t sc_pcallout; - bool sc_dying; device_t sc_audiodev; int sc_blksize;