git: 074babfb2812 - stable/13 - DEBUG_VFS_LOCKS: use witness if available

The branch stable/13 has been updated by kib:

URL: https://cgit.FreeBSD.org/src/commit/?id=074babfb2812c12caf99e3286f0a6c688ecf45bf

commit 074babfb2812c12caf99e3286f0a6c688ecf45bf
Author:     Konstantin Belousov <kib@FreeBSD.org>
AuthorDate: 2023-04-08 06:15:00 +0000
Commit:     Konstantin Belousov <kib@FreeBSD.org>
CommitDate: 2023-04-16 10:45:58 +0000

    DEBUG_VFS_LOCKS: use witness if available
    
    (cherry picked from commit 7b6fe2428a97921e8df882d0a24b87094c37b468)
---
 sys/kern/vfs_lookup.c |  1 +
 sys/kern/vfs_subr.c   | 16 +++++++++++++---
 sys/sys/vnode.h       |  1 +
 3 files changed, 15 insertions(+), 3 deletions(-)

diff --git a/sys/kern/vfs_lookup.c b/sys/kern/vfs_lookup.c
index 3ded2180ac82..b7ce93f3702d 100644
--- a/sys/kern/vfs_lookup.c
+++ b/sys/kern/vfs_lookup.c
@@ -161,6 +161,7 @@ nameiinit(void *dummy __unused)
 	    UMA_ALIGN_PTR, 0);
 	vfs_vector_op_register(&crossmp_vnodeops);
 	getnewvnode("crossmp", NULL, &crossmp_vnodeops, &vp_crossmp);
+	vp_crossmp->v_irflag |= VIRF_CROSSMP;
 }
 SYSINIT(vfs, SI_SUB_VFS, SI_ORDER_SECOND, nameiinit, NULL);
 
diff --git a/sys/kern/vfs_subr.c b/sys/kern/vfs_subr.c
index 67f707dd9edb..c4d8ceac7e2b 100644
--- a/sys/kern/vfs_subr.c
+++ b/sys/kern/vfs_subr.c
@@ -5526,14 +5526,18 @@ assert_vi_unlocked(struct vnode *vp, const char *str)
 void
 assert_vop_locked(struct vnode *vp, const char *str)
 {
-	int locked;
-
 	if (KERNEL_PANICKED() || vp == NULL)
 		return;
 
-	locked = VOP_ISLOCKED(vp);
+#ifdef WITNESS
+	if ((vp->v_irflag & VIRF_CROSSMP) == 0)
+		witness_assert(&vp->v_vnlock->lock_object, LA_LOCKED,
+		    __FILE__, __LINE__);
+#else
+	int locked = VOP_ISLOCKED(vp);
 	if (locked == 0 || locked == LK_EXCLOTHER)
 		vfs_badlock("is not locked but should be", str, vp);
+#endif
 }
 
 void
@@ -5542,8 +5546,14 @@ assert_vop_unlocked(struct vnode *vp, const char *str)
 	if (KERNEL_PANICKED() || vp == NULL)
 		return;
 
+#ifdef WITNESS
+	if ((vp->v_irflag & VIRF_CROSSMP) == 0)
+		witness_assert(&vp->v_vnlock->lock_object, LA_UNLOCKED,
+		    __FILE__, __LINE__);
+#else
 	if (VOP_ISLOCKED(vp) == LK_EXCLUSIVE)
 		vfs_badlock("is locked but should not be", str, vp);
+#endif
 }
 
 void
diff --git a/sys/sys/vnode.h b/sys/sys/vnode.h
index 2011f429141c..37cafdb0d5ae 100644
--- a/sys/sys/vnode.h
+++ b/sys/sys/vnode.h
@@ -248,6 +248,7 @@ struct xvnode {
 #define	VIRF_PGREAD	0x0002	/* Direct reads from the page cache are permitted,
 				   never cleared once set */
 #define	VIRF_MOUNTPOINT	0x0004	/* This vnode is mounted on */
+#define	VIRF_CROSSMP	0x0010	/* Cross-mp vnode, no locking */
 
 #define	VI_TEXT_REF	0x0001	/* Text ref grabbed use ref */
 #define	VI_MOUNT	0x0002	/* Mount in progress */