]> git.karo-electronics.de Git - karo-tx-linux.git/blobdiff - fs/inode.c
Merge remote-tracking branch 'mips/mips-for-linux-next'
[karo-tx-linux.git] / fs / inode.c
index 93a0625b46e490252c03dab43310919763a8eca9..b33ba8e021cc286d500d94abd64d8f85115ebcd2 100644 (file)
@@ -17,6 +17,7 @@
 #include <linux/prefetch.h>
 #include <linux/buffer_head.h> /* for inode_has_buffers */
 #include <linux/ratelimit.h>
+#include <linux/list_lru.h>
 #include "internal.h"
 
 /*
@@ -24,7 +25,7 @@
  *
  * inode->i_lock protects:
  *   inode->i_state, inode->i_hash, __iget()
- * inode->i_sb->s_inode_lru_lock protects:
+ * Inode LRU list locks protect:
  *   inode->i_sb->s_inode_lru, inode->i_lru
  * inode_sb_list_lock protects:
  *   sb->s_inodes, inode->i_sb_list
@@ -37,7 +38,7 @@
  *
  * inode_sb_list_lock
  *   inode->i_lock
- *     inode->i_sb->s_inode_lru_lock
+ *     Inode LRU list locks
  *
  * bdi->wb.list_lock
  *   inode->i_lock
@@ -70,33 +71,33 @@ EXPORT_SYMBOL(empty_aops);
  */
 struct inodes_stat_t inodes_stat;
 
-static DEFINE_PER_CPU(unsigned int, nr_inodes);
-static DEFINE_PER_CPU(unsigned int, nr_unused);
+static DEFINE_PER_CPU(unsigned long, nr_inodes);
+static DEFINE_PER_CPU(unsigned long, nr_unused);
 
 static struct kmem_cache *inode_cachep __read_mostly;
 
-static int get_nr_inodes(void)
+static long get_nr_inodes(void)
 {
        int i;
-       int sum = 0;
+       long sum = 0;
        for_each_possible_cpu(i)
                sum += per_cpu(nr_inodes, i);
        return sum < 0 ? 0 : sum;
 }
 
-static inline int get_nr_inodes_unused(void)
+static inline long get_nr_inodes_unused(void)
 {
        int i;
-       int sum = 0;
+       long sum = 0;
        for_each_possible_cpu(i)
                sum += per_cpu(nr_unused, i);
        return sum < 0 ? 0 : sum;
 }
 
-int get_nr_dirty_inodes(void)
+long get_nr_dirty_inodes(void)
 {
        /* not actually dirty inodes, but a wild approximation */
-       int nr_dirty = get_nr_inodes() - get_nr_inodes_unused();
+       long nr_dirty = get_nr_inodes() - get_nr_inodes_unused();
        return nr_dirty > 0 ? nr_dirty : 0;
 }
 
@@ -109,7 +110,7 @@ int proc_nr_inodes(ctl_table *table, int write,
 {
        inodes_stat.nr_inodes = get_nr_inodes();
        inodes_stat.nr_unused = get_nr_inodes_unused();
-       return proc_dointvec(table, write, buffer, lenp, ppos);
+       return proc_doulongvec_minmax(table, write, buffer, lenp, ppos);
 }
 #endif
 
@@ -401,13 +402,8 @@ EXPORT_SYMBOL(ihold);
 
 static void inode_lru_list_add(struct inode *inode)
 {
-       spin_lock(&inode->i_sb->s_inode_lru_lock);
-       if (list_empty(&inode->i_lru)) {
-               list_add(&inode->i_lru, &inode->i_sb->s_inode_lru);
-               inode->i_sb->s_nr_inodes_unused++;
+       if (list_lru_add(&inode->i_sb->s_inode_lru, &inode->i_lru))
                this_cpu_inc(nr_unused);
-       }
-       spin_unlock(&inode->i_sb->s_inode_lru_lock);
 }
 
 /*
@@ -425,13 +421,9 @@ void inode_add_lru(struct inode *inode)
 
 static void inode_lru_list_del(struct inode *inode)
 {
-       spin_lock(&inode->i_sb->s_inode_lru_lock);
-       if (!list_empty(&inode->i_lru)) {
-               list_del_init(&inode->i_lru);
-               inode->i_sb->s_nr_inodes_unused--;
+
+       if (list_lru_del(&inode->i_sb->s_inode_lru, &inode->i_lru))
                this_cpu_dec(nr_unused);
-       }
-       spin_unlock(&inode->i_sb->s_inode_lru_lock);
 }
 
 /**
@@ -675,24 +667,8 @@ int invalidate_inodes(struct super_block *sb, bool kill_dirty)
        return busy;
 }
 
-static int can_unuse(struct inode *inode)
-{
-       if (inode->i_state & ~I_REFERENCED)
-               return 0;
-       if (inode_has_buffers(inode))
-               return 0;
-       if (atomic_read(&inode->i_count))
-               return 0;
-       if (inode->i_data.nrpages)
-               return 0;
-       return 1;
-}
-
 /*
- * Walk the superblock inode LRU for freeable inodes and attempt to free them.
- * This is called from the superblock shrinker function with a number of inodes
- * to trim from the LRU. Inodes to be freed are moved to a temporary list and
- * then are freed outside inode_lock by dispose_list().
+ * Isolate the inode from the LRU in preparation for freeing it.
  *
  * Any inodes which are pinned purely because of attached pagecache have their
  * pagecache removed.  If the inode has metadata buffers attached to
@@ -706,89 +682,82 @@ static int can_unuse(struct inode *inode)
  * LRU does not have strict ordering. Hence we don't want to reclaim inodes
  * with this flag set because they are the inodes that are out of order.
  */
-void prune_icache_sb(struct super_block *sb, int nr_to_scan)
+static enum lru_status
+inode_lru_isolate(struct list_head *item, spinlock_t *lru_lock, void *arg)
 {
-       LIST_HEAD(freeable);
-       int nr_scanned;
-       unsigned long reap = 0;
+       struct list_head *freeable = arg;
+       struct inode    *inode = container_of(item, struct inode, i_lru);
 
-       spin_lock(&sb->s_inode_lru_lock);
-       for (nr_scanned = nr_to_scan; nr_scanned >= 0; nr_scanned--) {
-               struct inode *inode;
+       /*
+        * we are inverting the lru lock/inode->i_lock here, so use a trylock.
+        * If we fail to get the lock, just skip it.
+        */
+       if (!spin_trylock(&inode->i_lock))
+               return LRU_SKIP;
 
-               if (list_empty(&sb->s_inode_lru))
-                       break;
+       /*
+        * Referenced or dirty inodes are still in use. Give them another pass
+        * through the LRU as we canot reclaim them now.
+        */
+       if (atomic_read(&inode->i_count) ||
+           (inode->i_state & ~I_REFERENCED)) {
+               list_del_init(&inode->i_lru);
+               spin_unlock(&inode->i_lock);
+               this_cpu_dec(nr_unused);
+               return LRU_REMOVED;
+       }
 
-               inode = list_entry(sb->s_inode_lru.prev, struct inode, i_lru);
+       /* recently referenced inodes get one more pass */
+       if (inode->i_state & I_REFERENCED) {
+               inode->i_state &= ~I_REFERENCED;
+               spin_unlock(&inode->i_lock);
+               return LRU_ROTATE;
+       }
 
-               /*
-                * we are inverting the sb->s_inode_lru_lock/inode->i_lock here,
-                * so use a trylock. If we fail to get the lock, just move the
-                * inode to the back of the list so we don't spin on it.
-                */
-               if (!spin_trylock(&inode->i_lock)) {
-                       list_move(&inode->i_lru, &sb->s_inode_lru);
-                       continue;
+       if (inode_has_buffers(inode) || inode->i_data.nrpages) {
+               __iget(inode);
+               spin_unlock(&inode->i_lock);
+               spin_unlock(lru_lock);
+               if (remove_inode_buffers(inode)) {
+                       unsigned long reap;
+                       reap = invalidate_mapping_pages(&inode->i_data, 0, -1);
+                       if (current_is_kswapd())
+                               __count_vm_events(KSWAPD_INODESTEAL, reap);
+                       else
+                               __count_vm_events(PGINODESTEAL, reap);
+                       if (current->reclaim_state)
+                               current->reclaim_state->reclaimed_slab += reap;
                }
+               iput(inode);
+               spin_lock(lru_lock);
+               return LRU_RETRY;
+       }
 
-               /*
-                * Referenced or dirty inodes are still in use. Give them
-                * another pass through the LRU as we canot reclaim them now.
-                */
-               if (atomic_read(&inode->i_count) ||
-                   (inode->i_state & ~I_REFERENCED)) {
-                       list_del_init(&inode->i_lru);
-                       spin_unlock(&inode->i_lock);
-                       sb->s_nr_inodes_unused--;
-                       this_cpu_dec(nr_unused);
-                       continue;
-               }
+       WARN_ON(inode->i_state & I_NEW);
+       inode->i_state |= I_FREEING;
+       list_move(&inode->i_lru, freeable);
+       spin_unlock(&inode->i_lock);
 
-               /* recently referenced inodes get one more pass */
-               if (inode->i_state & I_REFERENCED) {
-                       inode->i_state &= ~I_REFERENCED;
-                       list_move(&inode->i_lru, &sb->s_inode_lru);
-                       spin_unlock(&inode->i_lock);
-                       continue;
-               }
-               if (inode_has_buffers(inode) || inode->i_data.nrpages) {
-                       __iget(inode);
-                       spin_unlock(&inode->i_lock);
-                       spin_unlock(&sb->s_inode_lru_lock);
-                       if (remove_inode_buffers(inode))
-                               reap += invalidate_mapping_pages(&inode->i_data,
-                                                               0, -1);
-                       iput(inode);
-                       spin_lock(&sb->s_inode_lru_lock);
-
-                       if (inode != list_entry(sb->s_inode_lru.next,
-                                               struct inode, i_lru))
-                               continue;       /* wrong inode or list_empty */
-                       /* avoid lock inversions with trylock */
-                       if (!spin_trylock(&inode->i_lock))
-                               continue;
-                       if (!can_unuse(inode)) {
-                               spin_unlock(&inode->i_lock);
-                               continue;
-                       }
-               }
-               WARN_ON(inode->i_state & I_NEW);
-               inode->i_state |= I_FREEING;
-               spin_unlock(&inode->i_lock);
+       this_cpu_dec(nr_unused);
+       return LRU_REMOVED;
+}
 
-               list_move(&inode->i_lru, &freeable);
-               sb->s_nr_inodes_unused--;
-               this_cpu_dec(nr_unused);
-       }
-       if (current_is_kswapd())
-               __count_vm_events(KSWAPD_INODESTEAL, reap);
-       else
-               __count_vm_events(PGINODESTEAL, reap);
-       spin_unlock(&sb->s_inode_lru_lock);
-       if (current->reclaim_state)
-               current->reclaim_state->reclaimed_slab += reap;
+/*
+ * Walk the superblock inode LRU for freeable inodes and attempt to free them.
+ * This is called from the superblock shrinker function with a number of inodes
+ * to trim from the LRU. Inodes to be freed are moved to a temporary list and
+ * then are freed outside inode_lock by dispose_list().
+ */
+long prune_icache_sb(struct super_block *sb, unsigned long nr_to_scan,
+                    int nid)
+{
+       LIST_HEAD(freeable);
+       long freed;
 
+       freed = list_lru_walk_node(&sb->s_inode_lru, nid, inode_lru_isolate,
+                                      &freeable, &nr_to_scan);
        dispose_list(&freeable);
+       return freed;
 }
 
 static void __wait_on_freeing_inode(struct inode *inode);