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Index: head/sys/kern/vfs_subr.c
===================================================================
--- head/sys/kern/vfs_subr.c
+++ head/sys/kern/vfs_subr.c
@@ -1805,20 +1805,13 @@
{
struct mount *mp;
+ VNPASS((vp->v_mflag & VMP_LAZYLIST) == 0, vp);
+
mp = vp->v_mount;
if (mp == NULL)
return;
MNT_ILOCK(mp);
VI_LOCK(vp);
- if (vp->v_mflag & VMP_LAZYLIST) {
- mtx_lock(&mp->mnt_listmtx);
- if (vp->v_mflag & VMP_LAZYLIST) {
- vp->v_mflag &= ~VMP_LAZYLIST;
- TAILQ_REMOVE(&mp->mnt_lazyvnodelist, vp, v_lazylist);
- mp->mnt_lazyvnodelistsize--;
- }
- mtx_unlock(&mp->mnt_listmtx);
- }
vp->v_mount = NULL;
VI_UNLOCK(vp);
VNASSERT(mp->mnt_nvnodelistsize > 0, vp,
@@ -3079,6 +3072,11 @@
if ((vp->v_mflag & VMP_LAZYLIST) != 0)
return;
+ /*
+ * We may get here for inactive routines after the vnode got doomed.
+ */
+ if (VN_IS_DOOMED(vp))
+ return;
mp = vp->v_mount;
mtx_lock(&mp->mnt_listmtx);
if ((vp->v_mflag & VMP_LAZYLIST) == 0) {
@@ -3089,7 +3087,31 @@
mtx_unlock(&mp->mnt_listmtx);
}
+/*
+ * This routine is only meant to be called from vgonel prior to dooming
+ * the vnode.
+ */
static void
+vunlazy_gone(struct vnode *vp)
+{
+ struct mount *mp;
+
+ ASSERT_VOP_ELOCKED(vp, __func__);
+ ASSERT_VI_LOCKED(vp, __func__);
+ VNPASS(!VN_IS_DOOMED(vp), vp);
+
+ if (vp->v_mflag & VMP_LAZYLIST) {
+ mp = vp->v_mount;
+ mtx_lock(&mp->mnt_listmtx);
+ VNPASS(vp->v_mflag & VMP_LAZYLIST, vp);
+ vp->v_mflag &= ~VMP_LAZYLIST;
+ TAILQ_REMOVE(&mp->mnt_lazyvnodelist, vp, v_lazylist);
+ mp->mnt_lazyvnodelistsize--;
+ mtx_unlock(&mp->mnt_listmtx);
+ }
+}
+
+static void
vdefer_inactive(struct vnode *vp)
{
@@ -3808,6 +3830,7 @@
*/
if (vp->v_irflag & VIRF_DOOMED)
return;
+ vunlazy_gone(vp);
vp->v_irflag |= VIRF_DOOMED;
/*
@@ -6221,8 +6244,6 @@
mnt_vnode_next_lazy_relock(struct vnode *mvp, struct mount *mp,
struct vnode *vp)
{
- const struct vnode *tmp;
- bool held, ret;
VNASSERT(mvp->v_mount == mp && mvp->v_type == VMARKER &&
TAILQ_NEXT(mvp, v_lazylist) != NULL, mvp,
@@ -6232,65 +6253,37 @@
ASSERT_VI_UNLOCKED(vp, __func__);
mtx_assert(&mp->mnt_listmtx, MA_OWNED);
- ret = false;
-
TAILQ_REMOVE(&mp->mnt_lazyvnodelist, mvp, v_lazylist);
TAILQ_INSERT_BEFORE(vp, mvp, v_lazylist);
- /*
- * Use a hold to prevent vp from disappearing while the mount vnode
- * list lock is dropped and reacquired. Normally a hold would be
- * acquired with vhold(), but that might try to acquire the vnode
- * interlock, which would be a LOR with the mount vnode list lock.
- */
- held = refcount_acquire_if_not_zero(&vp->v_holdcnt);
+ vholdnz(vp);
mtx_unlock(&mp->mnt_listmtx);
- if (!held)
- goto abort;
VI_LOCK(vp);
- if (!refcount_release_if_not_last(&vp->v_holdcnt)) {
- vdropl(vp);
- goto abort;
+ if (VN_IS_DOOMED(vp)) {
+ VNPASS((vp->v_mflag & VMP_LAZYLIST) == 0, vp);
+ goto out_lost;
}
- mtx_lock(&mp->mnt_listmtx);
-
+ VNPASS(vp->v_mflag & VMP_LAZYLIST, vp);
/*
- * Determine whether the vnode is still the next one after the marker,
- * excepting any other markers. If the vnode has not been doomed by
- * vgone() then the hold should have ensured that it remained on the
- * lazy list. If it has been doomed but is still on the lazy list,
- * don't abort, but rather skip over it (avoid spinning on doomed
- * vnodes).
+ * Since we had a period with no locks held we may be the last
+ * remaining user, in which case there is nothing to do.
*/
- tmp = mvp;
- do {
- tmp = TAILQ_NEXT(tmp, v_lazylist);
- } while (tmp != NULL && tmp->v_type == VMARKER);
- if (tmp != vp) {
- mtx_unlock(&mp->mnt_listmtx);
- VI_UNLOCK(vp);
- goto abort;
- }
-
- ret = true;
- goto out;
-abort:
+ if (!refcount_release_if_not_last(&vp->v_holdcnt))
+ goto out_lost;
+ mtx_lock(&mp->mnt_listmtx);
+ return (true);
+out_lost:
+ vdropl(vp);
maybe_yield();
mtx_lock(&mp->mnt_listmtx);
-out:
- if (ret)
- ASSERT_VI_LOCKED(vp, __func__);
- else
- ASSERT_VI_UNLOCKED(vp, __func__);
- mtx_assert(&mp->mnt_listmtx, MA_OWNED);
- return (ret);
+ return (false);
}
static struct vnode *
mnt_vnode_next_lazy(struct vnode **mvp, struct mount *mp, mnt_lazy_cb_t *cb,
void *cbarg)
{
- struct vnode *vp, *nvp;
+ struct vnode *vp;
mtx_assert(&mp->mnt_listmtx, MA_OWNED);
KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch"));
@@ -6306,7 +6299,8 @@
* long string of vnodes we don't care about and hog the list
* as a result. Check for it and requeue the marker.
*/
- if (VN_IS_DOOMED(vp) || !cb(vp, cbarg)) {
+ VNPASS(!VN_IS_DOOMED(vp), vp);
+ if (!cb(vp, cbarg)) {
if (!should_yield()) {
vp = TAILQ_NEXT(vp, v_lazylist);
continue;
@@ -6321,9 +6315,7 @@
goto restart;
}
/*
- * Try-lock because this is the wrong lock order. If that does
- * not succeed, drop the mount vnode list lock and try to
- * reacquire it and the vnode interlock in the right order.
+ * Try-lock because this is the wrong lock order.
*/
if (!VI_TRYLOCK(vp) &&
!mnt_vnode_next_lazy_relock(*mvp, mp, vp))
@@ -6331,11 +6323,9 @@
KASSERT(vp->v_type != VMARKER, ("locked marker %p", vp));
KASSERT(vp->v_mount == mp || vp->v_mount == NULL,
("alien vnode on the lazy list %p %p", vp, mp));
- if (vp->v_mount == mp && !VN_IS_DOOMED(vp))
- break;
- nvp = TAILQ_NEXT(vp, v_lazylist);
- VI_UNLOCK(vp);
- vp = nvp;
+ VNPASS(vp->v_mount == mp, vp);
+ VNPASS(!VN_IS_DOOMED(vp), vp);
+ break;
}
TAILQ_REMOVE(&mp->mnt_lazyvnodelist, *mvp, v_lazylist);

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