diff options
| -rw-r--r-- | share/man/man9/Makefile | 1 | ||||
| -rw-r--r-- | share/man/man9/sleep.9 | 27 | ||||
| -rw-r--r-- | sys/kern/kern_synch.c | 22 | ||||
| -rw-r--r-- | sys/sys/sleepqueue.h | 1 | ||||
| -rw-r--r-- | sys/sys/systm.h | 1 |
5 files changed, 47 insertions, 5 deletions
diff --git a/share/man/man9/Makefile b/share/man/man9/Makefile index 2298e39..64c11ab 100644 --- a/share/man/man9/Makefile +++ b/share/man/man9/Makefile @@ -997,6 +997,7 @@ MLINKS+=signal.9 cursig.9 \ signal.9 trapsignal.9 MLINKS+=sleep.9 msleep.9 \ sleep.9 msleep_spin.9 \ + sleep.9 pause.9 \ sleep.9 tsleep.9 \ sleep.9 wakeup.9 \ sleep.9 wakeup_one.9 diff --git a/share/man/man9/sleep.9 b/share/man/man9/sleep.9 index db97565..0973fc5 100644 --- a/share/man/man9/sleep.9 +++ b/share/man/man9/sleep.9 @@ -31,6 +31,7 @@ .Sh NAME .Nm msleep , .Nm msleep_spin , +.Nm pause , .Nm tsleep , .Nm wakeup .Nd wait for events @@ -39,12 +40,14 @@ .In sys/systm.h .In sys/proc.h .Ft int -.Fn tsleep "void *chan" "int priority" "const char *wmesg" "int timo" -.Ft int .Fn msleep "void *chan" "struct mtx *mtx" "int priority" "const char *wmesg" "int timo" .Ft int .Fn msleep_spin "void *chan" "struct mtx *mtx" "const char *wmesg" "int timo" .Ft void +.Fn pause "const char *wmesg" "int timo" +.Ft int +.Fn tsleep "void *chan" "int priority" "const char *wmesg" "int timo" +.Ft void .Fn wakeup "void *chan" .Ft void .Fn wakeup_one "void *chan" @@ -53,6 +56,7 @@ The functions .Fn tsleep , .Fn msleep , .Fn msleep_spin , +.Fn pause , .Fn wakeup , and .Fn wakeup_one @@ -61,12 +65,13 @@ If a thread must wait for an external event, it is put to sleep by .Fn tsleep , .Fn msleep , +.Fn msleep_spin , or -.Fn msleep_spin . +.Fn pause . The parameter .Fa chan is an arbitrary address that uniquely identifies the event on which -the thread is being asleep. +the thread is being put to sleep. All threads sleeping on a single .Fa chan are woken up later by @@ -184,6 +189,16 @@ and it does not support the and .Dv PCATCH flags. +.Pp +The +.Fn pause +function is a wrapper around +.Fn tsleep +that suspends execution of the current thread for the indicated timeout. +The thread can not be awakened early by signals or calls to +.Fn wakeup +or +.Fn wakeup_one. .Sh RETURN VALUES See above. .Sh SEE ALSO @@ -211,6 +226,10 @@ function appeared in and the .Fn msleep_spin function appeared in +.Fx 6.2 . +.The +.Fn pause +function appeared in .Fx 7.0 . .Pp The diff --git a/sys/kern/kern_synch.c b/sys/kern/kern_synch.c index 6cc7c70..089919c 100644 --- a/sys/kern/kern_synch.c +++ b/sys/kern/kern_synch.c @@ -69,6 +69,7 @@ SYSINIT(synch_setup, SI_SUB_KICK_SCHEDULER, SI_ORDER_FIRST, synch_setup, NULL) int hogticks; int lbolt; +static int pause_wchan; static struct callout loadav_callout; static struct callout lbolt_callout; @@ -164,7 +165,10 @@ msleep(ident, mtx, priority, wmesg, timo) if (TD_ON_SLEEPQ(td)) sleepq_remove(td, td->td_wchan); - flags = SLEEPQ_MSLEEP; + if (ident == &pause_wchan) + flags = SLEEPQ_PAUSE; + else + flags = SLEEPQ_MSLEEP; if (catch) flags |= SLEEPQ_INTERRUPTIBLE; @@ -308,6 +312,22 @@ msleep_spin(ident, mtx, wmesg, timo) } /* + * pause() is like tsleep() except that the intention is to not be + * explicitly woken up by another thread. Instead, the current thread + * simply wishes to sleep until the timeout expires. It is + * implemented using a dummy wait channel. + */ +int +pause(wmesg, timo) + const char *wmesg; + int timo; +{ + + KASSERT(timo != 0, ("pause: timeout required")); + return (tsleep(&pause_wchan, 0, wmesg, timo)); +} + +/* * Make all threads sleeping on the specified identifier runnable. */ void diff --git a/sys/sys/sleepqueue.h b/sys/sys/sleepqueue.h index 19a231d..15a673d 100644 --- a/sys/sys/sleepqueue.h +++ b/sys/sys/sleepqueue.h @@ -84,6 +84,7 @@ struct thread; #define SLEEPQ_TYPE 0x0ff /* Mask of sleep queue types. */ #define SLEEPQ_MSLEEP 0x00 /* Used by msleep/wakeup. */ #define SLEEPQ_CONDVAR 0x01 /* Used for a cv. */ +#define SLEEPQ_PAUSE 0x02 /* Used by pause. */ #define SLEEPQ_INTERRUPTIBLE 0x100 /* Sleep is interruptible. */ void init_sleepqueues(void); diff --git a/sys/sys/systm.h b/sys/sys/systm.h index 6fa2bfa..09cfac9 100644 --- a/sys/sys/systm.h +++ b/sys/sys/systm.h @@ -310,6 +310,7 @@ static __inline void splx(intrmask_t ipl __unused) { return; } int msleep(void *chan, struct mtx *mtx, int pri, const char *wmesg, int timo); int msleep_spin(void *chan, struct mtx *mtx, const char *wmesg, int timo); +int pause(const char *wmesg, int timo); #define tsleep(chan, pri, wmesg, timo) msleep(chan, NULL, pri, wmesg, timo) void wakeup(void *chan) __nonnull(1); void wakeup_one(void *chan) __nonnull(1); |
