Author: jhb
Date: Tue Nov 4 18:56:12 2008
New Revision: 184651
URL: http://svn.freebsd.org/changeset/base/184651
Log:
Quiet a WITNESS warning with the dirhash sx locks by setting the DUPOK
flag. Specifically, if two threads race to create a dirhash for a
directory, then one might already have created a private dirhash
structure (and locked it) when it realizes the directory now has a
structure and tries to lock that one.
Modified:
head/sys/ufs/ufs/ufs_dirhash.c
Modified: head/sys/ufs/ufs/ufs_dirhash.c
==============================================================================
--- head/sys/ufs/ufs/ufs_dirhash.c Tue Nov 4 18:54:44 2008
(r184650)
+++ head/sys/ufs/ufs/ufs_dirhash.c Tue Nov 4 18:56:12 2008
(r184651)
@@ -181,7 +181,16 @@ ufsdirhash_create(struct inode *ip)
if (ndh == NULL)
return (NULL);
refcount_init(&ndh->dh_refcount, 1);
- sx_init(&ndh->dh_lock, "dirhash");
+
+ /*
+ * The DUPOK is to prevent warnings from the
+ * sx_slock() a few lines down which is safe
+ * since the duplicate lock in that case is
+ * the one for this dirhash we are creating
+ * now which has no external references until
+ * after this function returns.
+ */
+ sx_init_flags(&ndh->dh_lock, "dirhash", SX_DUPOK);
sx_xlock(&ndh->dh_lock);
}
/*
_______________________________________________
svn-src-all@freebsd.org mailing list
http://lists.freebsd.org/mailman/listinfo/svn-src-all
To unsubscribe, send any mail to "[EMAIL PROTECTED]"
