[src/trunk]: src/sys A vnode is usually called "active", if it has an associa...

[hannken <hannken%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/20d87ef21025
branches:  trunk
changeset: 354102:20d87ef21025
user:      hannken <hannken%NetBSD.org@localhost>
date:      Sun Jun 04 07:58:29 2017 +0000

description:
A vnode is usually called "active", if it has an associated file system
node and a usecount greater zero.  Therefore rename state "VS_ACTIVE"
to "VS_LOADED" and add a new synthetic state "VS_ACTIVE" for VSTATE_ASSERT()
to assert an active vnode.

Add VSTATE_ASSERT_UNLOCKED() to be used with v_interlock unheld and
move the state assertion macros to sys/vnode_impl.h.

diffstat:

 sys/kern/vfs_subr.c  |  10 +++--
 sys/kern/vfs_vnode.c |  82 ++++++++++++++++++++++++++++-----------------------
 sys/sys/vnode_impl.h |  30 +++++++++++++++++-
 3 files changed, 79 insertions(+), 43 deletions(-)

diffs (truncated from 372 to 300 lines):

diff -r a8b35d47ea34 -r 20d87ef21025 sys/kern/vfs_subr.c
--- a/sys/kern/vfs_subr.c       Sun Jun 04 07:18:39 2017 +0000
+++ b/sys/kern/vfs_subr.c       Sun Jun 04 07:58:29 2017 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: vfs_subr.c,v 1.467 2017/05/26 14:34:19 riastradh Exp $ */
+/*     $NetBSD: vfs_subr.c,v 1.468 2017/06/04 07:58:29 hannken Exp $   */
 
 /*-
  * Copyright (c) 1997, 1998, 2004, 2005, 2007, 2008 The NetBSD Foundation, Inc.
@@ -68,7 +68,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: vfs_subr.c,v 1.467 2017/05/26 14:34:19 riastradh Exp $");
+__KERNEL_RCSID(0, "$NetBSD: vfs_subr.c,v 1.468 2017/06/04 07:58:29 hannken Exp $");
 
 #ifdef _KERNEL_OPT
 #include "opt_ddb.h"
@@ -1055,12 +1055,14 @@
 {
 
        switch (state) {
+       case VS_ACTIVE:
+               return "ACTIVE";
        case VS_MARKER:
                return "MARKER";
        case VS_LOADING:
                return "LOADING";
-       case VS_ACTIVE:
-               return "ACTIVE";
+       case VS_LOADED:
+               return "LOADED";
        case VS_BLOCKED:
                return "BLOCKED";
        case VS_RECLAIMING:
diff -r a8b35d47ea34 -r 20d87ef21025 sys/kern/vfs_vnode.c
--- a/sys/kern/vfs_vnode.c      Sun Jun 04 07:18:39 2017 +0000
+++ b/sys/kern/vfs_vnode.c      Sun Jun 04 07:58:29 2017 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: vfs_vnode.c,v 1.93 2017/05/28 16:39:41 hannken Exp $   */
+/*     $NetBSD: vfs_vnode.c,v 1.94 2017/06/04 07:58:29 hannken Exp $   */
 
 /*-
  * Copyright (c) 1997-2011 The NetBSD Foundation, Inc.
@@ -100,7 +100,7 @@
  *                     will never change its state.
  *     - LOADING       Vnode is associating underlying file system and not
  *                     yet ready to use.
- *     - ACTIVE        Vnode has associated underlying file system and is
+ *     - LOADED        Vnode has associated underlying file system and is
  *                     ready to use.
  *     - BLOCKED       Vnode is active but cannot get new references.
  *     - RECLAIMING    Vnode is disassociating from the underlying file
@@ -109,19 +109,19 @@
  *                     and is dead.
  *
  *     Valid state changes are:
- *     LOADING -> ACTIVE
+ *     LOADING -> LOADED
  *                     Vnode has been initialised in vcache_get() or
  *                     vcache_new() and is ready to use.
- *     ACTIVE -> RECLAIMING
+ *     LOADED -> RECLAIMING
  *                     Vnode starts disassociation from underlying file
  *                     system in vcache_reclaim().
  *     RECLAIMING -> RECLAIMED
  *                     Vnode finished disassociation from underlying file
  *                     system in vcache_reclaim().
- *     ACTIVE -> BLOCKED
+ *     LOADED -> BLOCKED
  *                     Either vcache_rekey*() is changing the vnode key or
  *                     vrelel() is about to call VOP_INACTIVE().
- *     BLOCKED -> ACTIVE
+ *     BLOCKED -> LOADED
  *                     The block condition is over.
  *     LOADING -> RECLAIMED
  *                     Either vcache_get() or vcache_new() failed to
@@ -156,7 +156,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: vfs_vnode.c,v 1.93 2017/05/28 16:39:41 hannken Exp $");
+__KERNEL_RCSID(0, "$NetBSD: vfs_vnode.c,v 1.94 2017/06/04 07:58:29 hannken Exp $");
 
 #include <sys/param.h>
 #include <sys/kernel.h>
@@ -231,26 +231,30 @@
 
 #if defined(DIAGNOSTIC)
 
+#define VSTATE_VALID(state) \
+       ((state) != VS_ACTIVE && (state) != VS_MARKER)
 #define VSTATE_GET(vp) \
        vstate_assert_get((vp), __func__, __LINE__)
 #define VSTATE_CHANGE(vp, from, to) \
        vstate_assert_change((vp), (from), (to), __func__, __LINE__)
 #define VSTATE_WAIT_STABLE(vp) \
        vstate_assert_wait_stable((vp), __func__, __LINE__)
-#define VSTATE_ASSERT(vp, state) \
-       vstate_assert((vp), (state), __func__, __LINE__)
 
-static void
-vstate_assert(vnode_t *vp, enum vnode_state state, const char *func, int line)
+void
+_vstate_assert(vnode_t *vp, enum vnode_state state, const char *func, int line)
 {
        vnode_impl_t *vip = VNODE_TO_VIMPL(vp);
 
        KASSERTMSG(mutex_owned(vp->v_interlock), "at %s:%d", func, line);
 
-       if (__predict_true(vip->vi_state == state))
+       if (state == VS_ACTIVE && vp->v_usecount > 0 &&
+           (vip->vi_state == VS_LOADED || vip->vi_state == VS_BLOCKED))
                return;
-       vnpanic(vp, "state is %s, expected %s at %s:%d",
-           vstate_name(vip->vi_state), vstate_name(state), func, line);
+       if (vip->vi_state == state)
+               return;
+       vnpanic(vp, "state is %s, usecount %d, expected %s at %s:%d",
+           vstate_name(vip->vi_state), vp->v_usecount,
+           vstate_name(state), func, line);
 }
 
 static enum vnode_state
@@ -259,7 +263,7 @@
        vnode_impl_t *vip = VNODE_TO_VIMPL(vp);
 
        KASSERTMSG(mutex_owned(vp->v_interlock), "at %s:%d", func, line);
-       if (vip->vi_state == VS_MARKER)
+       if (! VSTATE_VALID(vip->vi_state))
                vnpanic(vp, "state is %s at %s:%d",
                    vstate_name(vip->vi_state), func, line);
 
@@ -272,14 +276,14 @@
        vnode_impl_t *vip = VNODE_TO_VIMPL(vp);
 
        KASSERTMSG(mutex_owned(vp->v_interlock), "at %s:%d", func, line);
-       if (vip->vi_state == VS_MARKER)
+       if (! VSTATE_VALID(vip->vi_state))
                vnpanic(vp, "state is %s at %s:%d",
                    vstate_name(vip->vi_state), func, line);
 
-       while (vip->vi_state != VS_ACTIVE && vip->vi_state != VS_RECLAIMED)
+       while (vip->vi_state != VS_LOADED && vip->vi_state != VS_RECLAIMED)
                cv_wait(&vp->v_cv, vp->v_interlock);
 
-       if (vip->vi_state == VS_MARKER)
+       if (! VSTATE_VALID(vip->vi_state))
                vnpanic(vp, "state is %s at %s:%d",
                    vstate_name(vip->vi_state), func, line);
 }
@@ -294,10 +298,10 @@
        if (from == VS_LOADING)
                KASSERTMSG(mutex_owned(&vcache_lock), "at %s:%d", func, line);
 
-       if (from == VS_MARKER)
+       if (! VSTATE_VALID(from))
                vnpanic(vp, "from is %s at %s:%d",
                    vstate_name(from), func, line);
-       if (to == VS_MARKER)
+       if (! VSTATE_VALID(to))
                vnpanic(vp, "to is %s at %s:%d",
                    vstate_name(to), func, line);
        if (vip->vi_state != from)
@@ -311,7 +315,7 @@
        vip->vi_state = to;
        if (from == VS_LOADING)
                cv_broadcast(&vcache_cv);
-       if (to == VS_ACTIVE || to == VS_RECLAIMED)
+       if (to == VS_LOADED || to == VS_RECLAIMED)
                cv_broadcast(&vp->v_cv);
 }
 
@@ -323,14 +327,18 @@
        vstate_change((vp), (from), (to))
 #define VSTATE_WAIT_STABLE(vp) \
        vstate_wait_stable((vp))
-#define VSTATE_ASSERT(vp, state)
+void
+_vstate_assert(vnode_t *vp, enum vnode_state state, const char *func, int line)
+{
+
+}
 
 static void
 vstate_wait_stable(vnode_t *vp)
 {
        vnode_impl_t *vip = VNODE_TO_VIMPL(vp);
 
-       while (vip->vi_state != VS_ACTIVE && vip->vi_state != VS_RECLAIMED)
+       while (vip->vi_state != VS_LOADED && vip->vi_state != VS_RECLAIMED)
                cv_wait(&vp->v_cv, vp->v_interlock);
 }
 
@@ -342,7 +350,7 @@
        vip->vi_state = to;
        if (from == VS_LOADING)
                cv_broadcast(&vcache_cv);
-       if (to == VS_ACTIVE || to == VS_RECLAIMED)
+       if (to == VS_LOADED || to == VS_RECLAIMED)
                cv_broadcast(&vp->v_cv);
 }
 
@@ -528,7 +536,7 @@
        if (!mutex_tryenter(vp->v_interlock))
                return;
        /* Probe usecount and state. */
-       if (vp->v_usecount > 0 || VSTATE_GET(vp) != VS_ACTIVE) {
+       if (vp->v_usecount > 0 || VSTATE_GET(vp) != VS_LOADED) {
                mutex_exit(vp->v_interlock);
                return;
        }
@@ -752,7 +760,7 @@
        if (VSTATE_GET(vp) == VS_RECLAIMED) {
                VOP_UNLOCK(vp);
        } else {
-               VSTATE_CHANGE(vp, VS_ACTIVE, VS_BLOCKED);
+               VSTATE_CHANGE(vp, VS_LOADED, VS_BLOCKED);
                mutex_exit(vp->v_interlock);
 
                /*
@@ -768,7 +776,7 @@
                if (!recycle)
                        VOP_UNLOCK(vp);
                mutex_enter(vp->v_interlock);
-               VSTATE_CHANGE(vp, VS_BLOCKED, VS_ACTIVE);
+               VSTATE_CHANGE(vp, VS_BLOCKED, VS_LOADED);
                if (!recycle) {
                        if (vtryrele(vp)) {
                                mutex_exit(vp->v_interlock);
@@ -791,7 +799,7 @@
                 * otherwise just free it.
                 */
                if (recycle) {
-                       VSTATE_ASSERT(vp, VS_ACTIVE);
+                       VSTATE_ASSERT(vp, VS_LOADED);
                        /* vcache_reclaim drops the lock. */
                        vcache_reclaim(vp);
                }
@@ -910,14 +918,14 @@
        }
 
        /* If the vnode is already clean we're done. */
-       if (VSTATE_GET(vp) != VS_ACTIVE) {
+       if (VSTATE_GET(vp) != VS_LOADED) {
                VSTATE_ASSERT(vp, VS_RECLAIMED);
                vrelel(vp, 0);
                return true;
        }
 
        /* Prevent further references until the vnode is locked. */
-       VSTATE_CHANGE(vp, VS_ACTIVE, VS_BLOCKED);
+       VSTATE_CHANGE(vp, VS_LOADED, VS_BLOCKED);
        mutex_exit(vp->v_interlock);
 
        /*
@@ -929,7 +937,7 @@
        error = vn_lock(vp, LK_EXCLUSIVE | LK_RETRY | LK_NOWAIT);
 
        mutex_enter(vp->v_interlock);
-       VSTATE_CHANGE(vp, VS_BLOCKED, VS_ACTIVE);
+       VSTATE_CHANGE(vp, VS_BLOCKED, VS_LOADED);
 
        if (error) {
                mutex_exit(vp->v_interlock);
@@ -1024,7 +1032,7 @@
        vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
        mutex_enter(vp->v_interlock);
        VSTATE_WAIT_STABLE(vp);
-       if (VSTATE_GET(vp) == VS_ACTIVE)
+       if (VSTATE_GET(vp) == VS_LOADED)
                vcache_reclaim(vp);
        VSTATE_ASSERT(vp, VS_RECLAIMED);
        vrelel(vp, 0);
@@ -1199,7 +1207,7 @@
 
        if (__predict_false(VSTATE_GET(vp) == VS_RECLAIMED))
                error = ENOENT;
-       else if (__predict_false(VSTATE_GET(vp) != VS_ACTIVE))
+       else if (__predict_false(VSTATE_GET(vp) != VS_LOADED))
                error = EBUSY;
        else if (vp->v_usecount == 0)
                vp->v_usecount = 1;
@@ -1237,7 +1245,7 @@
                        mutex_exit(vp->v_interlock);
                return ENOENT;
        }
-       VSTATE_ASSERT(vp, VS_ACTIVE);
+       VSTATE_ASSERT(vp, VS_LOADED);
        if (vp->v_usecount == 0)
                vp->v_usecount = 1;
        else
@@ -1349,7 +1357,7 @@
        mutex_enter(&vcache_lock);
        new_vip->vi_key.vk_key = new_key;
        mutex_enter(vp->v_interlock);
-       VSTATE_CHANGE(vp, VS_LOADING, VS_ACTIVE);
+       VSTATE_CHANGE(vp, VS_LOADING, VS_LOADED);
        mutex_exit(vp->v_interlock);
        mutex_exit(&vcache_lock);