diff options
| author | Andrew Gallatin <gallatin@FreeBSD.org> | 2021-08-05 21:16:30 +0000 |
|---|---|---|
| committer | Andrew Gallatin <gallatin@FreeBSD.org> | 2021-08-05 21:16:30 +0000 |
| commit | 1b97a054f3acaf13a5c8361b7b80e10ad16257b9 (patch) | |
| tree | c52f42c863ea8d01fe6a7776a38f0caff75247a2 | |
| parent | 8482aa77481a1576df7a19dbeaccb91243fbb2a3 (diff) | |
tsleep: Add a PNOLOCK flag
Add a PNOLOCK flag so that, in the race circumstance where
wakeup races are externally mitigated, tsleep() can be
called with a sleep time of 0 without triggering an
an assertion.
Reviewed by: jhb
Sponsored by: Netflix
| -rw-r--r-- | sys/kern/kern_synch.c | 3 | ||||
| -rw-r--r-- | sys/sys/param.h | 3 |
2 files changed, 4 insertions, 2 deletions
diff --git a/sys/kern/kern_synch.c b/sys/kern/kern_synch.c index 793c5309a30b..7bf5193fb7b1 100644 --- a/sys/kern/kern_synch.c +++ b/sys/kern/kern_synch.c @@ -148,7 +148,8 @@ _sleep(const void *ident, struct lock_object *lock, int priority, #endif WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, lock, "Sleeping on \"%s\"", wmesg); - KASSERT(sbt != 0 || mtx_owned(&Giant) || lock != NULL, + KASSERT(sbt != 0 || mtx_owned(&Giant) || lock != NULL || + (priority & PNOLOCK) != 0, ("sleeping without a lock")); KASSERT(ident != NULL, ("_sleep: NULL ident")); KASSERT(TD_IS_RUNNING(td), ("_sleep: curthread not running")); diff --git a/sys/sys/param.h b/sys/sys/param.h index f842b344e9f9..8864063e3d9b 100644 --- a/sys/sys/param.h +++ b/sys/sys/param.h @@ -246,7 +246,8 @@ #define PRIMASK 0x0ff #define PCATCH 0x100 /* OR'd with pri for tsleep to check signals */ #define PDROP 0x200 /* OR'd with pri to stop re-entry of interlock mutex */ -#define PRILASTFLAG 0x200 /* Last flag defined above */ +#define PNOLOCK 0x400 /* OR'd with pri to allow sleeping w/o a lock */ +#define PRILASTFLAG 0x400 /* Last flag defined above */ #define NZERO 0 /* default "nice" */ |