diff options
| author | bdrewery <bdrewery@FreeBSD.org> | 2016-03-29 16:07:51 +0000 |
|---|---|---|
| committer | bdrewery <bdrewery@FreeBSD.org> | 2016-03-29 16:07:51 +0000 |
| commit | 6f05cd22f0529efa92d1c3bf53cc9588751086ec (patch) | |
| tree | 97464ab3f7838ae680ac45a9ae641935bfd88866 /share/man/man9/sx.9 | |
| parent | 1dc6d847e3c83ec708ac8c0fd7e609ca1ba28a25 (diff) | |
| download | FreeBSD-src-6f05cd22f0529efa92d1c3bf53cc9588751086ec.zip FreeBSD-src-6f05cd22f0529efa92d1c3bf53cc9588751086ec.tar.gz | |
Reword descriptions of asserting locks held without WITNESS.
This corrects an error in r296947 in that it is not possible to assert
which thread holds a shared (or read) lock, but it is possible to assert
that one is held. Just not very useful.
MFC after: 1 week
Submitted by: wblock, jhb
Reviewed by: kib (earlier version), jhb, wblock
Sponsored by: EMC / Isilon Storage Division
Differential Revision: https://reviews.freebsd.org/D5659
Diffstat (limited to 'share/man/man9/sx.9')
| -rw-r--r-- | share/man/man9/sx.9 | 17 |
1 files changed, 11 insertions, 6 deletions
diff --git a/share/man/man9/sx.9 b/share/man/man9/sx.9 index 677f8b7..f09584a 100644 --- a/share/man/man9/sx.9 +++ b/share/man/man9/sx.9 @@ -26,7 +26,7 @@ .\" .\" $FreeBSD$ .\" -.Dd March 16, 2016 +.Dd March 28, 2016 .Dt SX 9 .Os .Sh NAME @@ -320,11 +320,16 @@ end up sleeping while holding a mutex, which is not allowed. .Xr rwlock 9 , .Xr sema 9 .Sh BUGS -In the -.No non- Ns Dv WITNESS -case, the +A kernel without +.Dv WITNESS +cannot assert whether the current thread does or does not hold a shared lock. .Dv SA_LOCKED and .Dv SA_SLOCKED -assertions merely check that some thread holds a shared lock. -They do not ensure that the current thread holds a shared lock. +can only assert that +.Em any +thread holds a shared lock. +They cannot ensure that the current thread holds a shared lock. +Further, +.Dv SA_UNLOCKED +can only assert that the current thread does not hold an exclusive lock. |
