diff options
| author |   visa <visa@openbsd.org> | 2019-12-12 16:31:06 +0000 |
|---|---|---|
| committer | visa <visa@openbsd.org> | 2019-12-12 16:31:06 +0000 |
| commit | 696db59407941672885dff96f4aba7b78ea52eaa (patch) | |
| tree | 7aa615d232d474b8908a6a7551501e6a4941a449 /sys/sys/event.h | |
| parent | Unhook <machine/stdarg.h> from <sys/stdarg.h>. Nowadays all the (diff) | |
| download | wireguard-openbsd-696db59407941672885dff96f4aba7b78ea52eaa.tar.xz wireguard-openbsd-696db59407941672885dff96f4aba7b78ea52eaa.zip | |
Allow sleeping inside kqueue event filters.
In kqueue_scan(), threads have to get an exclusive access to a knote
before processing by calling knote_acquire(). This prevents the knote
from being destroyed while it is still in use. knote_acquire() also
blocks other threads from processing the knote. Once knote processing
has finished, the thread has to call knote_release().
The kqueue subsystem is still serialized by the kernel lock. If an event
filter sleeps, the kernel lock is released and another thread might
enter kqueue_scan(). kqueue_scan() uses start and end markers to keep
track of the scan's progress and it has to be aware of other threads'
markers.
This patch is a revised version of mpi@'s work derived
from DragonFly BSD. kqueue_check() has been adapted from NetBSD.
Tested by anton@, sashan@
OK mpi@, anton@, sashan@
Diffstat (limited to 'sys/sys/event.h')
| -rw-r--r-- | sys/sys/event.h | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/sys/sys/event.h b/sys/sys/event.h index e29c1128975..909367aea33 100644 --- a/sys/sys/event.h +++ b/sys/sys/event.h @@ -1,4 +1,4 @@ -/* $OpenBSD: event.h,v 1.30 2018/01/13 12:58:40 robert Exp $ */ +/* $OpenBSD: event.h,v 1.31 2019/12/12 16:31:06 visa Exp $ */ /*- * Copyright (c) 1999,2000,2001 Jonathan Lemon <jlemon@FreeBSD.org> @@ -125,6 +125,8 @@ SLIST_HEAD(klist, knote); #ifdef _KERNEL +#define EVFILT_MARKER 0xf /* placemarker for tailq */ + /* * hint flag for in-kernel use - must not equal any existing note */ @@ -170,6 +172,8 @@ struct knote { #define KN_QUEUED 0x0002 /* event is on queue */ #define KN_DISABLED 0x0004 /* event is disabled */ #define KN_DETACHED 0x0008 /* knote is detached */ +#define KN_PROCESSING 0x0010 /* knote is being processed */ +#define KN_WAITING 0x0020 /* waiting on processing */ #define kn_id kn_kevent.ident #define kn_filter kn_kevent.filter |