[src/trunk]: src/sys/kern Change vcache_reclaim() to remove vnode from vnode ...

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

details:   https://anonhg.NetBSD.org/src/rev/e669c5973191
branches:  trunk
changeset: 347300:e669c5973191
user:      hannken <hannken%NetBSD.org@localhost>
date:      Sat Aug 20 12:33:57 2016 +0000

description:
Change vcache_reclaim() to remove vnode from vnode cache once the
vnode was reclaimed from the file system.

diffstat:

 sys/kern/vfs_vnode.c |  34 ++++++++++++++++++++++++++++++----
 1 files changed, 30 insertions(+), 4 deletions(-)

diffs (91 lines):

diff -r 45a3b4bfcca3 -r e669c5973191 sys/kern/vfs_vnode.c
--- a/sys/kern/vfs_vnode.c      Sat Aug 20 12:31:37 2016 +0000
+++ b/sys/kern/vfs_vnode.c      Sat Aug 20 12:33:57 2016 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: vfs_vnode.c,v 1.54 2016/08/20 12:31:37 hannken Exp $   */
+/*     $NetBSD: vfs_vnode.c,v 1.55 2016/08/20 12:33:57 hannken Exp $   */
 
 /*-
  * Copyright (c) 1997-2011 The NetBSD Foundation, Inc.
@@ -156,7 +156,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: vfs_vnode.c,v 1.54 2016/08/20 12:31:37 hannken Exp $");
+__KERNEL_RCSID(0, "$NetBSD: vfs_vnode.c,v 1.55 2016/08/20 12:33:57 hannken Exp $");
 
 #define _VFS_VNODE_PRIVATE
 
@@ -1495,6 +1495,10 @@
 vcache_reclaim(vnode_t *vp)
 {
        lwp_t *l = curlwp;
+       struct vcache_node *node = VP_TO_VN(vp);
+       uint32_t hash;
+       uint8_t temp_buf[64], *temp_key;
+       size_t temp_key_len;
        bool recycle, active;
        int error;
 
@@ -1504,6 +1508,7 @@
        KASSERT(vp->v_usecount != 0);
 
        active = (vp->v_usecount > 1);
+       temp_key_len = node->vn_key.vk_key_len;
        /*
         * Prevent the vnode from being recycled or brought into use
         * while we clean it out.
@@ -1516,6 +1521,17 @@
        vp->v_iflag &= ~(VI_TEXT|VI_EXECMAP);
        mutex_exit(vp->v_interlock);
 
+       /* Replace the vnode key with a temporary copy. */
+       if (node->vn_key.vk_key_len > sizeof(temp_buf)) {
+               temp_key = kmem_alloc(temp_key_len, KM_SLEEP);
+       } else {
+               temp_key = temp_buf;
+       }
+       mutex_enter(&vcache.lock);
+       memcpy(temp_key, node->vn_key.vk_key, temp_key_len);
+       node->vn_key.vk_key = temp_key;
+       mutex_exit(&vcache.lock);
+
        /*
         * Clean out any cached data associated with the vnode.
         * If purging an active vnode, it must be closed and
@@ -1564,6 +1580,16 @@
        atomic_inc_uint(&dead_rootmount->mnt_refcnt);
        vfs_insmntque(vp, dead_rootmount);
 
+       /* Remove from vnode cache. */
+       hash = vcache_hash(&node->vn_key);
+       mutex_enter(&vcache.lock);
+       KASSERT(node == vcache_hash_lookup(&node->vn_key, hash));
+       SLIST_REMOVE(&vcache.hashtab[hash & vcache.hashmask],
+           node, vcache_node, vn_hash);
+       mutex_exit(&vcache.lock);
+       if (temp_key != temp_buf)
+               kmem_free(temp_key, temp_key_len);
+
        /* Done with purge, notify sleepers of the grim news. */
        mutex_enter(vp->v_interlock);
        vp->v_op = dead_vnodeop_p;
@@ -1581,6 +1607,7 @@
 void
 vcache_remove(struct mount *mp, const void *key, size_t key_len)
 {
+#ifdef DIAGNOSTIC
        uint32_t hash;
        struct vcache_key vcache_key;
        struct vcache_node *node;
@@ -1593,9 +1620,8 @@
        mutex_enter(&vcache.lock);
        node = vcache_hash_lookup(&vcache_key, hash);
        KASSERT(node != NULL);
-       SLIST_REMOVE(&vcache.hashtab[hash & vcache.hashmask],
-           node, vcache_node, vn_hash);
        mutex_exit(&vcache.lock);
+#endif
 }
 
 /*