Author: marcel
Date: Thu May 9 16:28:18 2013
New Revision: 250411
URL: http://svnweb.freebsd.org/changeset/base/250411
Log:
Add option WITNESS_NO_VNODE to suppress printing LORs between VNODE
locks. To support this, VNODE locks are created with the LK_IS_VNODE
flag. This flag is propagated down using the LO_IS_VNODE flag.
Note that WITNESS still records the LOR. Only the printing and the
optional entering into the kernel debugger is bypassed with the
WITNESS_NO_VNODE option.
Modified:
head/sys/conf/options
head/sys/kern/kern_lock.c
head/sys/kern/subr_witness.c
head/sys/kern/vfs_subr.c
head/sys/sys/lock.h
head/sys/sys/lockmgr.h
Modified: head/sys/conf/options
==============================================================================
--- head/sys/conf/options Thu May 9 16:09:39 2013 (r250410)
+++ head/sys/conf/options Thu May 9 16:28:18 2013 (r250411)
@@ -672,6 +672,7 @@ KTR_ENTRIES opt_global.h
KTR_VERBOSE opt_ktr.h
WITNESS opt_global.h
WITNESS_KDB opt_witness.h
+WITNESS_NO_VNODE opt_witness.h
WITNESS_SKIPSPIN opt_witness.h
# options for ACPI support
Modified: head/sys/kern/kern_lock.c
==============================================================================
--- head/sys/kern/kern_lock.c Thu May 9 16:09:39 2013 (r250410)
+++ head/sys/kern/kern_lock.c Thu May 9 16:28:18 2013 (r250411)
@@ -393,6 +393,8 @@ lockinit(struct lock *lk, int pri, const
iflags |= LO_WITNESS;
if (flags & LK_QUIET)
iflags |= LO_QUIET;
+ if (flags & LK_IS_VNODE)
+ iflags |= LO_IS_VNODE;
iflags |= flags & (LK_ADAPTIVE | LK_NOSHARE);
lk->lk_lock = LK_UNLOCKED;
Modified: head/sys/kern/subr_witness.c
==============================================================================
--- head/sys/kern/subr_witness.c Thu May 9 16:09:39 2013
(r250410)
+++ head/sys/kern/subr_witness.c Thu May 9 16:28:18 2013
(r250411)
@@ -1289,7 +1289,19 @@ witness_checkorder(struct lock_object *l
w->w_reversed = w1->w_reversed = 1;
witness_increment_graph_generation();
mtx_unlock_spin(&w_mtx);
-
+
+#ifdef WITNESS_NO_VNODE
+ /*
+ * There are known LORs between VNODE locks. They are
+ * not an indication of a bug. VNODE locks are flagged
+ * as such (LO_IS_VNODE) and we don't yell if the LOR
+ * is between 2 VNODE locks.
+ */
+ if ((lock->lo_flags & LO_IS_VNODE) != 0 &&
+ (lock1->li_lock->lo_flags & LO_IS_VNODE) != 0)
+ return;
+#endif
+
/*
* Ok, yell about it.
*/
Modified: head/sys/kern/vfs_subr.c
==============================================================================
--- head/sys/kern/vfs_subr.c Thu May 9 16:09:39 2013 (r250410)
+++ head/sys/kern/vfs_subr.c Thu May 9 16:28:18 2013 (r250411)
@@ -1037,7 +1037,7 @@ alloc:
* By default, don't allow shared locks unless filesystems
* opt-in.
*/
- lockinit(vp->v_vnlock, PVFS, tag, VLKTIMEOUT, LK_NOSHARE);
+ lockinit(vp->v_vnlock, PVFS, tag, VLKTIMEOUT, LK_NOSHARE | LK_IS_VNODE);
/*
* Initialize bufobj.
*/
Modified: head/sys/sys/lock.h
==============================================================================
--- head/sys/sys/lock.h Thu May 9 16:09:39 2013 (r250410)
+++ head/sys/sys/lock.h Thu May 9 16:28:18 2013 (r250411)
@@ -79,6 +79,7 @@ struct lock_class {
#define LO_SLEEPABLE 0x00100000 /* Lock may be held while
sleeping. */
#define LO_UPGRADABLE 0x00200000 /* Lock may be
upgraded/downgraded. */
#define LO_DUPOK 0x00400000 /* Don't check for duplicate
acquires */
+#define LO_IS_VNODE 0x00800000 /* Tell WITNESS about a VNODE
lock */
#define LO_CLASSMASK 0x0f000000 /* Class index bitmask. */
#define LO_NOPROFILE 0x10000000 /* Don't profile this lock */
Modified: head/sys/sys/lockmgr.h
==============================================================================
--- head/sys/sys/lockmgr.h Thu May 9 16:09:39 2013 (r250410)
+++ head/sys/sys/lockmgr.h Thu May 9 16:28:18 2013 (r250411)
@@ -146,6 +146,7 @@ _lockmgr_args_rw(struct lock *lk, u_int
#define LK_NOWITNESS 0x000010
#define LK_QUIET 0x000020
#define LK_ADAPTIVE 0x000040
+#define LK_IS_VNODE 0x000080 /* Tell WITNESS about a VNODE
lock */
/*
* Additional attributes to be used in lockmgr().
_______________________________________________
svn-src-head@freebsd.org mailing list
http://lists.freebsd.org/mailman/listinfo/svn-src-head
To unsubscribe, send any mail to "svn-src-head-unsubscr...@freebsd.org"
