diff options
| author | jhb <jhb@FreeBSD.org> | 2007-03-09 16:59:27 +0000 |
|---|---|---|
| committer | jhb <jhb@FreeBSD.org> | 2007-03-09 16:59:27 +0000 |
| commit | 0090f876632dab1384a595e9bb4d6b2cca1ef035 (patch) | |
| tree | a3d010bc8d1234efba13a07d5cf7c37d2a6ae1d1 /share | |
| parent | bf4e259df634b3fb790a6bcc5a12b27f692b0436 (diff) | |
| download | FreeBSD-src-0090f876632dab1384a595e9bb4d6b2cca1ef035.zip FreeBSD-src-0090f876632dab1384a595e9bb4d6b2cca1ef035.tar.gz | |
- Document cv_wait_unlock(9).
- Don't claim that the mutex is atomically reacquired when a cv_wait
routine returns. There's nothing atomic or magical about the lock
reacquire. The only magic is that we atomically drop the lock by
placing the thread on the sleep queue before dropping the lock.
Diffstat (limited to 'share')
| -rw-r--r-- | share/man/man9/Makefile | 1 | ||||
| -rw-r--r-- | share/man/man9/condvar.9 | 11 |
2 files changed, 11 insertions, 1 deletions
diff --git a/share/man/man9/Makefile b/share/man/man9/Makefile index af7bac2..64793de 100644 --- a/share/man/man9/Makefile +++ b/share/man/man9/Makefile @@ -505,6 +505,7 @@ MLINKS+=condvar.9 cv_broadcast.9 \ condvar.9 cv_timedwait_sig.9 \ condvar.9 cv_wait.9 \ condvar.9 cv_wait_sig.9 \ + condvar.9 cv_wait_unlock.9 \ condvar.9 cv_wmesg.9 MLINKS+=config_intrhook.9 config_intrhook_disestablish.9 \ config_intrhook.9 config_intrhook_establish.9 diff --git a/share/man/man9/condvar.9 b/share/man/man9/condvar.9 index 1a8730e..97d3134 100644 --- a/share/man/man9/condvar.9 +++ b/share/man/man9/condvar.9 @@ -35,6 +35,7 @@ .Nm cv_destroy , .Nm cv_wait , .Nm cv_wait_sig , +.Nm cv_wait_unlock , .Nm cv_timedwait , .Nm cv_timedwait_sig , .Nm cv_signal , @@ -54,6 +55,8 @@ .Fn cv_wait "struct cv *cvp" "struct mtx *mp" .Ft int .Fn cv_wait_sig "struct cv *cvp" "struct mtx *mp" +.Ft void +.Fn cv_wait_unlock "struct cv *cvp" "struct mtx *mp" .Ft int .Fn cv_timedwait "struct cv *cvp" "struct mtx *mp" "int timo" .Ft int @@ -84,6 +87,7 @@ Condition variables are destroyed with Threads wait on condition variables by calling .Fn cv_wait , .Fn cv_wait_sig , +.Fn cv_wait_unlock , .Fn cv_timedwait , or .Fn cv_timedwait_sig . @@ -110,13 +114,17 @@ A thread must hold before calling .Fn cv_wait , .Fn cv_wait_sig , +.Fn cv_wait_unlock , .Fn cv_timedwait , or .Fn cv_timedwait_sig . When a thread waits on a condition, .Fa mp -is atomically released before the thread is blocked, then atomically reacquired +is atomically released before the thread is blocked, then reacquired before the function call returns. +The +.Fn cv_wait_unlock +function does not reacquire the lock before returning. All waiters must pass the same .Fa mp in conjunction with @@ -125,6 +133,7 @@ in conjunction with When .Fn cv_wait , .Fn cv_wait_sig , +.Fn cv_wait_unlock , .Fn cv_timedwait , and .Fn cv_timedwait_sig |
