diff options
| author | Jonathan Gray <jsg@cvs.openbsd.org> | 2007-05-14 16:39:35 +0000 |
|---|---|---|
| committer | Jonathan Gray <jsg@cvs.openbsd.org> | 2007-05-14 16:39:35 +0000 |
| commit | 31c58c1227785032f5a34554a093758ac993a13f (patch) | |
| tree | eba3447aeab8083d90e88fdc2b9fe3960ec3fa6f | |
| parent | 580d6d57f685db7b890620d6d0c0985d12540c1b (diff) | |
Add notes about sleeping with held locks and interrupt handler usage.
Based on comments by art, and tweaked by jmc.
ok art@
| -rw-r--r-- | share/man/man9/mutex.9 | 7 | ||||
| -rw-r--r-- | share/man/man9/rwlock.9 | 5 |
2 files changed, 10 insertions, 2 deletions
diff --git a/share/man/man9/mutex.9 b/share/man/man9/mutex.9 index b1b91b0aca9..416152d6c0d 100644 --- a/share/man/man9/mutex.9 +++ b/share/man/man9/mutex.9 @@ -1,4 +1,4 @@ -.\" $OpenBSD: mutex.9,v 1.2 2007/05/13 11:34:25 jsg Exp $ +.\" $OpenBSD: mutex.9,v 1.3 2007/05/14 16:39:34 jsg Exp $ .\" .\" Copyright (c) 2005 Pedro Martelletto <pedro@openbsd.org> .\" All rights reserved. @@ -71,6 +71,11 @@ functions were written by .An Artur Grabowski .Aq art@openbsd.org . .Sh CAVEATS +As these are spinning locks, don't sleep while holding one. +.Pp +If using a mutex in an interrupt handler, locks must be initialised +with the correct IPL or deadlock will occur. +.Pp Multiple mutexes may be nested, but not interleaved. This is okay: .Bd -literal -offset indent diff --git a/share/man/man9/rwlock.9 b/share/man/man9/rwlock.9 index d1773fab23a..1bc64e52155 100644 --- a/share/man/man9/rwlock.9 +++ b/share/man/man9/rwlock.9 @@ -1,4 +1,4 @@ -.\" $OpenBSD: rwlock.9,v 1.5 2007/04/10 21:07:48 art Exp $ +.\" $OpenBSD: rwlock.9,v 1.6 2007/05/14 16:39:34 jsg Exp $ .\" .\" Copyright (c) 2006 Pedro Martelletto <pedro@openbsd.org> .\" All rights reserved. @@ -127,3 +127,6 @@ The functions were written by .An Artur Grabowski .Aq art@openbsd.org . +.Sh CAVEATS +While it is safe to sleep with an rwlock held, they cannot +be used in an interrupt handler as an rwlock is bound to a process. |