Merge branch 'for-linus' of git://oss.sgi.com/xfs/xfs

* 'for-linus' of git://oss.sgi.com/xfs/xfs:
  xfs: add a shrinker to background inode reclaim

diff --git a/fs/xfs/linux-2.6/xfs_super.c b/fs/xfs/linux-2.6/xfs_super.c
index 52e06b4..29f1edc 100644 (file)
--- a/fs/xfs/linux-2.6/xfs_super.c
+++ b/fs/xfs/linux-2.6/xfs_super.c
@@ -1209,6 +1209,7 @@ xfs_fs_put_super(
 
        xfs_unmountfs(mp);
        xfs_freesb(mp);
+       xfs_inode_shrinker_unregister(mp);
        xfs_icsb_destroy_counters(mp);
        xfs_close_devices(mp);
        xfs_dmops_put(mp);
@@ -1622,6 +1623,8 @@ xfs_fs_fill_super(
        if (error)
                goto fail_vnrele;
 
+       xfs_inode_shrinker_register(mp);
+
        kfree(mtpt);
        return 0;
 
@@ -1867,6 +1870,7 @@ init_xfs_fs(void)
                goto out_cleanup_procfs;
 
        vfs_initquota();
+       xfs_inode_shrinker_init();
 
        error = register_filesystem(&xfs_fs_type);
        if (error)
@@ -1894,6 +1898,7 @@ exit_xfs_fs(void)
 {
        vfs_exitquota();
        unregister_filesystem(&xfs_fs_type);
+       xfs_inode_shrinker_destroy();
        xfs_sysctl_unregister();
        xfs_cleanup_procfs();
        xfs_buf_terminate();

diff --git a/fs/xfs/linux-2.6/xfs_sync.c b/fs/xfs/linux-2.6/xfs_sync.c
index fd96982..a427c63 100644 (file)
--- a/fs/xfs/linux-2.6/xfs_sync.c
+++ b/fs/xfs/linux-2.6/xfs_sync.c
@@ -95,7 +95,8 @@ xfs_inode_ag_walk(
                                           struct xfs_perag *pag, int flags),
        int                     flags,
        int                     tag,
-       int                     exclusive)
+       int                     exclusive,
+       int                     *nr_to_scan)
 {
        uint32_t                first_index;
        int                     last_error = 0;
@@ -134,7 +135,7 @@ restart:
                if (error == EFSCORRUPTED)
                        break;
 
-       } while (1);
+       } while ((*nr_to_scan)--);
 
        if (skipped) {
                delay(1);
@@ -150,12 +151,15 @@ xfs_inode_ag_iterator(
                                           struct xfs_perag *pag, int flags),
        int                     flags,
        int                     tag,
-       int                     exclusive)
+       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++) {
                struct xfs_perag        *pag;
 
@@ -165,14 +169,18 @@ xfs_inode_ag_iterator(
                        continue;
                }
                error = xfs_inode_ag_walk(mp, pag, execute, flags, tag,
-                                               exclusive);
+                                               exclusive, &nr);
                xfs_perag_put(pag);
                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);
 }
 
@@ -291,7 +299,7 @@ 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, 0);
+                                     XFS_ICI_NO_TAG, 0, NULL);
        if (error)
                return XFS_ERROR(error);
 
@@ -310,7 +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, 0);
+                                    XFS_ICI_NO_TAG, 0, NULL);
 }
 
 STATIC int
@@ -673,6 +681,7 @@ __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++;
 }
 
 /*
@@ -705,6 +714,7 @@ __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--;
 }
 
 /*
@@ -854,5 +864,93 @@ xfs_reclaim_inodes(
        int             mode)
 {
        return xfs_inode_ag_iterator(mp, xfs_reclaim_inode, mode,
-                                       XFS_ICI_RECLAIM_TAG, 1);
+                                       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;
+       struct xfs_perag *pag;
+       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++) {
+
+                       pag = xfs_perag_get(mp, ag);
+                       if (!pag->pag_ici_init) {
+                               xfs_perag_put(pag);
+                               continue;
+                       }
+                       reclaimable += pag->pag_ici_reclaimable;
+                       xfs_perag_put(pag);
+               }
+       }
+       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);
 }

diff --git a/fs/xfs/linux-2.6/xfs_sync.h b/fs/xfs/linux-2.6/xfs_sync.h
index d480c34..cdcbaac 100644 (file)
--- a/fs/xfs/linux-2.6/xfs_sync.h
+++ b/fs/xfs/linux-2.6/xfs_sync.h
@@ -53,6 +53,11 @@ void __xfs_inode_clear_reclaim_tag(struct xfs_mount *mp, struct xfs_perag *pag,
 int xfs_sync_inode_valid(struct xfs_inode *ip, struct xfs_perag *pag);
 int xfs_inode_ag_iterator(struct xfs_mount *mp,
        int (*execute)(struct xfs_inode *ip, struct xfs_perag *pag, int flags),
-       int flags, int tag, int write_lock);
+       int flags, int tag, int write_lock, int *nr_to_scan);
+
+void xfs_inode_shrinker_init(void);
+void xfs_inode_shrinker_destroy(void);
+void xfs_inode_shrinker_register(struct xfs_mount *mp);
+void xfs_inode_shrinker_unregister(struct xfs_mount *mp);
 
 #endif

diff --git a/fs/xfs/quota/xfs_qm_syscalls.c b/fs/xfs/quota/xfs_qm_syscalls.c
index 5d0ee8d..50bee07 100644 (file)
--- a/fs/xfs/quota/xfs_qm_syscalls.c
+++ b/fs/xfs/quota/xfs_qm_syscalls.c
@@ -891,7 +891,8 @@ xfs_qm_dqrele_all_inodes(
        uint             flags)
 {
        ASSERT(mp->m_quotainfo);
-       xfs_inode_ag_iterator(mp, xfs_dqrele_inode, flags, XFS_ICI_NO_TAG, 0);
+       xfs_inode_ag_iterator(mp, xfs_dqrele_inode, flags,
+                               XFS_ICI_NO_TAG, 0, NULL);
 }
 
 /*------------------------------------------------------------------------*/

diff --git a/fs/xfs/xfs_ag.h b/fs/xfs/xfs_ag.h
index b1a5a1f..abb8222 100644 (file)
--- a/fs/xfs/xfs_ag.h
+++ b/fs/xfs/xfs_ag.h
@@ -223,6 +223,7 @@ typedef struct xfs_perag {
        int             pag_ici_init;   /* incore inode cache initialised */
        rwlock_t        pag_ici_lock;   /* incore inode lock */
        struct radix_tree_root pag_ici_root;    /* incore inode cache root */
+       int             pag_ici_reclaimable;    /* reclaimable inodes */
 #endif
        int             pagb_count;     /* pagb slots in use */
        xfs_perag_busy_t pagb_list[XFS_PAGB_NUM_SLOTS]; /* unstable blocks */

diff --git a/fs/xfs/xfs_mount.h b/fs/xfs/xfs_mount.h
index 4fa0bc7..9ff48a1 100644 (file)
--- a/fs/xfs/xfs_mount.h
+++ b/fs/xfs/xfs_mount.h
@@ -259,6 +259,7 @@ typedef struct xfs_mount {
        wait_queue_head_t       m_wait_single_sync_task;
        __int64_t               m_update_flags; /* sb flags we need to update
                                                   on the next remount,rw */
+       struct list_head        m_mplist;       /* inode shrinker mount list */
 } xfs_mount_t;
 
 /*