diff options
| author | jhb <jhb@FreeBSD.org> | 2007-03-21 19:28:20 +0000 |
|---|---|---|
| committer | jhb <jhb@FreeBSD.org> | 2007-03-21 19:28:20 +0000 |
| commit | 08da44e27516b630d6cbf52c35d4f1b35d08de38 (patch) | |
| tree | 2fb38f6a510f332d49c81e60b0a249034b60b296 /sys/kern/kern_lock.c | |
| parent | 46edec2346d7678769ef5afe43c12651dbe830aa (diff) | |
| download | FreeBSD-src-08da44e27516b630d6cbf52c35d4f1b35d08de38.zip FreeBSD-src-08da44e27516b630d6cbf52c35d4f1b35d08de38.tar.gz | |
Handle the case when a thread is blocked on a lockmgr lock with LK_DRAIN
in DDB's 'show sleepchain'.
MFC after: 3 days
Diffstat (limited to 'sys/kern/kern_lock.c')
| -rw-r--r-- | sys/kern/kern_lock.c | 19 |
1 files changed, 16 insertions, 3 deletions
diff --git a/sys/kern/kern_lock.c b/sys/kern/kern_lock.c index 02254a4..3b67bfa 100644 --- a/sys/kern/kern_lock.c +++ b/sys/kern/kern_lock.c @@ -661,9 +661,22 @@ lockmgr_chain(struct thread *td, struct thread **ownerp) lkp = td->td_wchan; /* Simple test to see if wchan points to a lockmgr lock. */ - if (lkp->lk_wmesg != td->td_wmesg) - return (0); - + if (lkp->lk_wmesg == td->td_wmesg) + goto ok; + + /* + * If this thread is doing a DRAIN, then it would be asleep on + * &lkp->lk_flags rather than lkp. + */ + lkp = (struct lock *)((char *)td->td_wchan - + offsetof(struct lock, lk_flags)); + if (lkp->lk_wmesg == td->td_wmesg && (lkp->lk_flags & LK_WAITDRAIN)) + goto ok; + + /* Doen't seem to be a lockmgr lock. */ + return (0); + +ok: /* Ok, we think we have a lockmgr lock, so output some details. */ db_printf("blocked on lk \"%s\" ", lkp->lk_wmesg); if (lkp->lk_sharecount) { |
