--- fs/xfs/linux-2.6/xfs_sync.c
+++ fs/xfs/linux-2.6/xfs_sync.c
@@ -64,7 +64,6 @@ xfs_inode_ag_lookup(
* as the tree is sparse and a gang lookup walks to find
* the number of objects requested.
*/
- read_lock(&pag->pag_ici_lock);
if (tag == XFS_ICI_NO_TAG) {
nr_found = radix_tree_gang_lookup(&pag->pag_ici_root,
(void **)&ip, *first_index, 1);
@@ -73,7 +72,7 @@ xfs_inode_ag_lookup(
(void **)&ip, *first_index, 1, tag);
}
if (!nr_found)
- goto unlock;
+ return NULL;
/*
* Update the index for the next lookup. Catch overflows
@@ -83,13 +82,8 @@ xfs_inode_ag_lookup(
*/
*first_index = XFS_INO_TO_AGINO(mp, ip->i_ino + 1);
if (*first_index < XFS_INO_TO_AGINO(mp, ip->i_ino))
- goto unlock;
-
+ return NULL;
return ip;
-
-unlock:
- read_unlock(&pag->pag_ici_lock);
- return NULL;
}
STATIC int
@@ -99,7 +93,9 @@ xfs_inode_ag_walk(
int (*execute)(struct xfs_inode *ip,
struct xfs_perag *pag, int flags),
int flags,
- int tag)
+ int tag,
+ int exclusive,
+ int *nr_to_scan)
{
struct xfs_perag *pag = &mp->m_perag[ag];
uint32_t first_index;
@@ -113,10 +109,20 @@ restart:
int error = 0;
xfs_inode_t *ip;
+ if (exclusive)
+ write_lock(&pag->pag_ici_lock);
+ else
+ read_lock(&pag->pag_ici_lock);
ip = xfs_inode_ag_lookup(mp, pag, &first_index, tag);
- if (!ip)
+ if (!ip) {
+ if (exclusive)
+ write_unlock(&pag->pag_ici_lock);
+ else
+ read_unlock(&pag->pag_ici_lock);
break;
+ }
+ /* execute releases pag->pag_ici_lock */
error = execute(ip, pag, flags);
if (error == EAGAIN) {
skipped++;
@@ -124,13 +130,12 @@ restart:
}
if (error)
last_error = error;
- /*
- * bail out if the filesystem is corrupted.
- */
+
+ /* bail out if the filesystem is corrupted. */
if (error == EFSCORRUPTED)
break;
- } while (1);
+ } while ((*nr_to_scan)--);
if (skipped) {
delay(1);
@@ -147,22 +152,31 @@ xfs_inode_ag_iterator(
int (*execute)(struct xfs_inode *ip,
struct xfs_perag *pag, int flags),
int flags,
- int tag)
+ int tag,
+ int exclusive,
+ int *nr_to_scan)
{
int error = 0;
int last_error = 0;
xfs_agnumber_t ag;
+ int nr;
+ nr = nr_to_scan ? *nr_to_scan : INT_MAX;
for (ag = 0; ag < mp->m_sb.sb_agcount; ag++) {
if (!mp->m_perag[ag].pag_ici_init)
continue;
- error = xfs_inode_ag_walk(mp, ag, execute, flags, tag);
+ error = xfs_inode_ag_walk(mp, ag, execute, flags, tag,
+ exclusive, &nr);
if (error) {
last_error = error;
if (error == EFSCORRUPTED)
break;
}
+ if (nr <= 0)
+ break;
}
+ if (nr_to_scan)
+ *nr_to_scan = nr;
return XFS_ERROR(last_error);
}
@@ -173,30 +187,31 @@ xfs_sync_inode_valid(
struct xfs_perag *pag)
{
struct inode *inode = VFS_I(ip);
+ int error = EFSCORRUPTED;
/* nothing to sync during shutdown */
- if (XFS_FORCED_SHUTDOWN(ip->i_mount)) {
- read_unlock(&pag->pag_ici_lock);
- return EFSCORRUPTED;
- }
+ if (XFS_FORCED_SHUTDOWN(ip->i_mount))
+ goto out_unlock;
- /*
- * If we can't get a reference on the inode, it must be in reclaim.
- * Leave it for the reclaim code to flush. Also avoid inodes that
- * haven't been fully initialised.
- */
- if (!igrab(inode)) {
- read_unlock(&pag->pag_ici_lock);
- return ENOENT;
- }
- read_unlock(&pag->pag_ici_lock);
+ /* avoid new or reclaimable inodes. Leave for reclaim code to flush */
+ error = ENOENT;
+ if (xfs_iflags_test(ip, XFS_INEW | XFS_IRECLAIMABLE | XFS_IRECLAIM))
+ goto out_unlock;
+
+ /* If we can't grab the inode, it must on it's way to reclaim. */
+ if (!igrab(inode))
+ goto out_unlock;
- if (is_bad_inode(inode) || xfs_iflags_test(ip, XFS_INEW)) {
+ if (is_bad_inode(inode)) {
IRELE(ip);
- return ENOENT;
+ goto out_unlock;
}
- return 0;
+ /* inode is valid */
+ error = 0;
+out_unlock:
+ read_unlock(&pag->pag_ici_lock);
+ return error;
}
STATIC int
@@ -281,7 +296,7 @@ xfs_sync_data(
ASSERT((flags & ~(SYNC_TRYLOCK|SYNC_WAIT)) == 0);
error = xfs_inode_ag_iterator(mp, xfs_sync_inode_data, flags,
- XFS_ICI_NO_TAG);
+ XFS_ICI_NO_TAG, 0, NULL);
if (error)
return XFS_ERROR(error);
@@ -303,7 +318,7 @@ xfs_sync_attr(
ASSERT((flags & ~SYNC_WAIT) == 0);
return xfs_inode_ag_iterator(mp, xfs_sync_inode_attr, flags,
- XFS_ICI_NO_TAG);
+ XFS_ICI_NO_TAG, 0, NULL);
}
STATIC int
@@ -663,67 +678,6 @@ xfs_syncd_stop(
kthread_stop(mp->m_sync_task);
}
-int
-xfs_reclaim_inode(
- xfs_inode_t *ip,
- int locked,
- int sync_mode)
-{
- xfs_perag_t *pag = xfs_get_perag(ip->i_mount, ip->i_ino);
-
- /* The hash lock here protects a thread in xfs_iget_core from
- * racing with us on linking the inode back with a vnode.
- * Once we have the XFS_IRECLAIM flag set it will not touch
- * us.
- */
- write_lock(&pag->pag_ici_lock);
- spin_lock(&ip->i_flags_lock);
- if (__xfs_iflags_test(ip, XFS_IRECLAIM) ||
- !__xfs_iflags_test(ip, XFS_IRECLAIMABLE)) {
- spin_unlock(&ip->i_flags_lock);
- write_unlock(&pag->pag_ici_lock);
- if (locked) {
- xfs_ifunlock(ip);
- xfs_iunlock(ip, XFS_ILOCK_EXCL);
- }
- return -EAGAIN;
- }
- __xfs_iflags_set(ip, XFS_IRECLAIM);
- spin_unlock(&ip->i_flags_lock);
- write_unlock(&pag->pag_ici_lock);
- xfs_put_perag(ip->i_mount, pag);
-
- /*
- * If the inode is still dirty, then flush it out. If the inode
- * is not in the AIL, then it will be OK to flush it delwri as
- * long as xfs_iflush() does not keep any references to the inode.
- * We leave that decision up to xfs_iflush() since it has the
- * knowledge of whether it's OK to simply do a delwri flush of
- * the inode or whether we need to wait until the inode is
- * pulled from the AIL.
- * We get the flush lock regardless, though, just to make sure
- * we don't free it while it is being flushed.
- */
- if (!locked) {
- xfs_ilock(ip, XFS_ILOCK_EXCL);
- xfs_iflock(ip);
- }
-
- /*
- * In the case of a forced shutdown we rely on xfs_iflush() to
- * wait for the inode to be unpinned before returning an error.
- */
- if (!is_bad_inode(VFS_I(ip)) && xfs_iflush(ip, sync_mode) == 0) {
- /* synchronize with xfs_iflush_done */
- xfs_iflock(ip);
- xfs_ifunlock(ip);
- }
-
- xfs_iunlock(ip, XFS_ILOCK_EXCL);
- xfs_ireclaim(ip);
- return 0;
-}
-
void
__xfs_inode_set_reclaim_tag(
struct xfs_perag *pag,
@@ -732,6 +686,7 @@ __xfs_inode_set_reclaim_tag(
radix_tree_tag_set(&pag->pag_ici_root,
XFS_INO_TO_AGINO(ip->i_mount, ip->i_ino),
XFS_ICI_RECLAIM_TAG);
+ pag->pag_ici_reclaimable++;
}
/*
@@ -746,12 +701,12 @@ xfs_inode_set_reclaim_tag(
xfs_mount_t *mp = ip->i_mount;
xfs_perag_t *pag = xfs_get_perag(mp, ip->i_ino);
- read_lock(&pag->pag_ici_lock);
+ write_lock(&pag->pag_ici_lock);
spin_lock(&ip->i_flags_lock);
__xfs_inode_set_reclaim_tag(pag, ip);
__xfs_iflags_set(ip, XFS_IRECLAIMABLE);
spin_unlock(&ip->i_flags_lock);
- read_unlock(&pag->pag_ici_lock);
+ write_unlock(&pag->pag_ici_lock);
xfs_put_perag(mp, pag);
}
@@ -763,22 +718,59 @@ __xfs_inode_clear_reclaim_tag(
{
radix_tree_tag_clear(&pag->pag_ici_root,
XFS_INO_TO_AGINO(mp, ip->i_ino), XFS_ICI_RECLAIM_TAG);
+ pag->pag_ici_reclaimable--;
}
STATIC int
-xfs_reclaim_inode_now(
+xfs_reclaim_inode(
struct xfs_inode *ip,
struct xfs_perag *pag,
- int flags)
+ int sync_mode)
{
- /* ignore if already under reclaim */
- if (xfs_iflags_test(ip, XFS_IRECLAIM)) {
- read_unlock(&pag->pag_ici_lock);
+ /*
+ * The radix tree lock here protects a thread in xfs_iget from racing
+ * with us starting reclaim on the inode. Once we have the
+ * XFS_IRECLAIM flag set it will not touch us.
+ */
+ spin_lock(&ip->i_flags_lock);
+ ASSERT_ALWAYS(__xfs_iflags_test(ip, XFS_IRECLAIMABLE));
+ if (__xfs_iflags_test(ip, XFS_IRECLAIM)) {
+ /* ignore as it is already under reclaim */
+ spin_unlock(&ip->i_flags_lock);
+ write_unlock(&pag->pag_ici_lock);
return 0;
}
- read_unlock(&pag->pag_ici_lock);
+ __xfs_iflags_set(ip, XFS_IRECLAIM);
+ spin_unlock(&ip->i_flags_lock);
+ write_unlock(&pag->pag_ici_lock);
+
+ /*
+ * If the inode is still dirty, then flush it out. If the inode
+ * is not in the AIL, then it will be OK to flush it delwri as
+ * long as xfs_iflush() does not keep any references to the inode.
+ * We leave that decision up to xfs_iflush() since it has the
+ * knowledge of whether it's OK to simply do a delwri flush of
+ * the inode or whether we need to wait until the inode is
+ * pulled from the AIL.
+ * We get the flush lock regardless, though, just to make sure
+ * we don't free it while it is being flushed.
+ */
+ xfs_ilock(ip, XFS_ILOCK_EXCL);
+ xfs_iflock(ip);
- return xfs_reclaim_inode(ip, 0, flags);
+ /*
+ * In the case of a forced shutdown we rely on xfs_iflush() to
+ * wait for the inode to be unpinned before returning an error.
+ */
+ if (!is_bad_inode(VFS_I(ip)) && xfs_iflush(ip, sync_mode) == 0) {
+ /* synchronize with xfs_iflush_done */
+ xfs_iflock(ip);
+ xfs_ifunlock(ip);
+ }
+
+ xfs_iunlock(ip, XFS_ILOCK_EXCL);
+ xfs_ireclaim(ip);
+ return 0;
}
int
@@ -786,6 +778,89 @@ xfs_reclaim_inodes(
xfs_mount_t *mp,
int mode)
{
- return xfs_inode_ag_iterator(mp, xfs_reclaim_inode_now, mode,
- XFS_ICI_RECLAIM_TAG);
+ return xfs_inode_ag_iterator(mp, xfs_reclaim_inode, mode,
+ XFS_ICI_RECLAIM_TAG, 1, NULL);
+}
+
+/*
+ * Shrinker infrastructure.
+ *
+ * This is all far more complex than it needs to be. It adds a global list of
+ * mounts because the shrinkers can only call a global context. We need to make
+ * the shrinkers pass a context to avoid the need for global state.
+ */
+static LIST_HEAD(xfs_mount_list);
+static struct rw_semaphore xfs_mount_list_lock;
+
+static int
+xfs_reclaim_inode_shrink(
+ int nr_to_scan,
+ gfp_t gfp_mask)
+{
+ struct xfs_mount *mp;
+ xfs_agnumber_t ag;
+ int reclaimable = 0;
+
+ if (nr_to_scan) {
+ if (!(gfp_mask & __GFP_FS))
+ return -1;
+
+ down_read(&xfs_mount_list_lock);
+ list_for_each_entry(mp, &xfs_mount_list, m_mplist) {
+ xfs_inode_ag_iterator(mp, xfs_reclaim_inode, 0,
+ XFS_ICI_RECLAIM_TAG, 1, &nr_to_scan);
+ if (nr_to_scan <= 0)
+ break;
+ }
+ up_read(&xfs_mount_list_lock);
+ }
+
+ down_read(&xfs_mount_list_lock);
+ list_for_each_entry(mp, &xfs_mount_list, m_mplist) {
+ for (ag = 0; ag < mp->m_sb.sb_agcount; ag++) {
+
+ if (!mp->m_perag[ag].pag_ici_init)
+ continue;
+ reclaimable += mp->m_perag[ag].pag_ici_reclaimable;
+ }
+ }
+ up_read(&xfs_mount_list_lock);
+ return reclaimable;
+}
+
+static struct shrinker xfs_inode_shrinker = {
+ .shrink = xfs_reclaim_inode_shrink,
+ .seeks = DEFAULT_SEEKS,
+};
+
+void __init
+xfs_inode_shrinker_init(void)
+{
+ init_rwsem(&xfs_mount_list_lock);
+ register_shrinker(&xfs_inode_shrinker);
+}
+
+void
+xfs_inode_shrinker_destroy(void)
+{
+ ASSERT(list_empty(&xfs_mount_list));
+ unregister_shrinker(&xfs_inode_shrinker);
+}
+
+void
+xfs_inode_shrinker_register(
+ struct xfs_mount *mp)
+{
+ down_write(&xfs_mount_list_lock);
+ list_add_tail(&mp->m_mplist, &xfs_mount_list);
+ up_write(&xfs_mount_list_lock);
+}
+
+void
+xfs_inode_shrinker_unregister(
+ struct xfs_mount *mp)
+{
+ down_write(&xfs_mount_list_lock);
+ list_del(&mp->m_mplist);
+ up_write(&xfs_mount_list_lock);
}
projects / ziggy471-frankenstein-kernel.git / blobdiff