diff options
| author | John Baldwin <jhb@FreeBSD.org> | 2002-04-02 16:51:20 +0000 |
|---|---|---|
| committer | John Baldwin <jhb@FreeBSD.org> | 2002-04-02 16:51:20 +0000 |
| commit | 48c343df5fb2f0fda70dabd21b09774fe51920b4 (patch) | |
| tree | 211db454fadbbb5d0e1d196aafbca4e5236082b0 /sys/kern | |
| parent | 3eb933c093664f7d8c949d8f93375f0fddd66ad2 (diff) | |
| download | src-48c343df5fb2f0fda70dabd21b09774fe51920b4.tar.gz src-48c343df5fb2f0fda70dabd21b09774fe51920b4.zip | |
Explicitly document how we implicitly enforce the lock order of sleep
locks before spin locks.
Notes
Notes:
svn path=/head/; revision=93676
Diffstat (limited to 'sys/kern')
| -rw-r--r-- | sys/kern/subr_witness.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/sys/kern/subr_witness.c b/sys/kern/subr_witness.c index 53fbb9647ab4..ec98ba0e90ac 100644 --- a/sys/kern/subr_witness.c +++ b/sys/kern/subr_witness.c @@ -474,6 +474,11 @@ witness_lock(struct lock_object *lock, int flags, const char *file, int line) td = curthread; if (class->lc_flags & LC_SLEEPLOCK) { + /* + * Since spin locks include a critical section, this check + * impliclty enforces a lock order of all sleep locks before + * all spin locks. + */ if (td->td_critnest != 0 && (flags & LOP_TRYLOCK) == 0) panic("blockable sleep lock (%s) %s @ %s:%d", class->lc_name, lock->lo_name, file, line); |