[PATCH v6 12/31] fs: convert inode and dentry shrinking to be node aware

Glauber Costa
2013-05-12T18:13:33Z

From: Dave Chinner <dchinner@redhat.com>

Now that the shrinker is passing a nodemask in the scan control
structure, we can pass this to the the generic LRU list code to
isolate reclaim to the lists on matching nodes.

This requires a small amount of refactoring of the LRU list API,
which might be best split out into a separate patch.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Glauber Costa <glommer@parallels.com>
Acked-by: Mel Gorman <mgorman@suse.de>
---
fs/dcache.c | 8 +++++---
fs/inode.c | 7 ++++---
fs/internal.h | 6 ++++--
fs/super.c | 22 +++++++++++++---------
fs/xfs/xfs_super.c | 6 ++++--
include/linux/fs.h | 4 ++--
include/linux/list_lru.h | 22 +++++++++++++++++++---
lib/list_lru.c | 15 ++++++++-------
8 files changed, 59 insertions(+), 31 deletions(-)

diff --git a/fs/dcache.c b/fs/dcache.c
index ba14661..20ab9c0 100644
--- a/fs/dcache.c
+++ b/fs/dcache.c
@@ -875,6 +875,7 @@ dentry_lru_isolate(struct list_head *item, spinlock_t *lru_lock, void *arg)
* prune_dcache_sb - shrink the dcache
* @sb: superblock
* @nr_to_scan : number of entries to try to free
+ * @nodes_to_walk: which nodes to scan for freeable entities
*
* Attempt to shrink the superblock dcache LRU by @nr_to_scan entries. This is
* done when we need more memory an called from the superblock shrinker
@@ -883,13 +884,14 @@ dentry_lru_isolate(struct list_head *item, spinlock_t *lru_lock, void *arg)
* This function may fail to free any resources if all the dentries are in
* use.
*/
-long prune_dcache_sb(struct super_block *sb, unsigned long nr_to_scan)
+long prune_dcache_sb(struct super_block *sb, unsigned long nr_to_scan,
+ nodemask_t *nodes_to_walk)
{
LIST_HEAD(dispose);
long freed;

- freed = list_lru_walk(&sb->s_dentry_lru, dentry_lru_isolate,
- &dispose, nr_to_scan);
+ freed = list_lru_walk_nodemask(&sb->s_dentry_lru, dentry_lru_isolate,
+ &dispose, nr_to_scan, nodes_to_walk);
shrink_dentry_list(&dispose);
return freed;
}
diff --git a/fs/inode.c b/fs/inode.c
index ff66f49..3cf4cb0 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -746,13 +746,14 @@ inode_lru_isolate(struct list_head *item, spinlock_t *lru_lock, void *arg)
* 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)
+long prune_icache_sb(struct super_block *sb, unsigned long nr_to_scan,
+ nodemask_t *nodes_to_walk)
{
LIST_HEAD(freeable);
long freed;

- freed = list_lru_walk(&sb->s_inode_lru, inode_lru_isolate,
- &freeable, nr_to_scan);
+ freed = list_lru_walk_nodemask(&sb->s_inode_lru, inode_lru_isolate,
+ &freeable, nr_to_scan, nodes_to_walk);
dispose_list(&freeable);
return freed;
}
diff --git a/fs/internal.h b/fs/internal.h
index bb7b6e4..91900f2 100644
--- a/fs/internal.h
+++ b/fs/internal.h
@@ -110,7 +110,8 @@ extern int open_check_o_direct(struct file *f);
* inode.c
*/
extern spinlock_t inode_sb_list_lock;
-extern long prune_icache_sb(struct super_block *sb, unsigned long nr_to_scan);
+extern long prune_icache_sb(struct super_block *sb, unsigned long nr_to_scan,
+ nodemask_t *nodes_to_scan);
extern void inode_add_lru(struct inode *inode);

/*
@@ -126,7 +127,8 @@ extern int invalidate_inodes(struct super_block *, bool);
* dcache.c
*/
extern struct dentry *__d_alloc(struct super_block *, const struct qstr *);
-extern long prune_dcache_sb(struct super_block *sb, unsigned long nr_to_scan);
+extern long prune_dcache_sb(struct super_block *sb, unsigned long nr_to_scan,
+ nodemask_t *nodes_to_scan);

/*
* read_write.c
diff --git a/fs/super.c b/fs/super.c
index 66f5cde..5c7b879 100644
--- a/fs/super.c
+++ b/fs/super.c
@@ -75,10 +75,10 @@ static long super_cache_scan(struct shrinker *shrink, struct shrink_control *sc)
return -1;

if (sb->s_op && sb->s_op->nr_cached_objects)
- fs_objects = sb->s_op->nr_cached_objects(sb);
+ fs_objects = sb->s_op->nr_cached_objects(sb, &sc->nodes_to_scan);

- inodes = list_lru_count(&sb->s_inode_lru);
- dentries = list_lru_count(&sb->s_dentry_lru);
+ inodes = list_lru_count_nodemask(&sb->s_inode_lru, &sc->nodes_to_scan);
+ dentries = list_lru_count_nodemask(&sb->s_dentry_lru, &sc->nodes_to_scan);
total_objects = dentries + inodes + fs_objects + 1;

/* proportion the scan between the caches */
@@ -89,13 +89,14 @@ static long super_cache_scan(struct shrinker *shrink, struct shrink_control *sc)
* prune the dcache first as the icache is pinned by it, then
* prune the icache, followed by the filesystem specific caches
*/
- freed = prune_dcache_sb(sb, dentries);
- freed += prune_icache_sb(sb, inodes);
+ freed = prune_dcache_sb(sb, dentries, &sc->nodes_to_scan);
+ freed += prune_icache_sb(sb, inodes, &sc->nodes_to_scan);

if (fs_objects) {
fs_objects = mult_frac(sc->nr_to_scan, fs_objects,
total_objects);
- freed += sb->s_op->free_cached_objects(sb, fs_objects);
+ freed += sb->s_op->free_cached_objects(sb, fs_objects,
+ &sc->nodes_to_scan);
}

drop_super(sb);
@@ -113,10 +114,13 @@ static long super_cache_count(struct shrinker *shrink, struct shrink_control *sc
return -1;

if (sb->s_op && sb->s_op->nr_cached_objects)
- total_objects = sb->s_op->nr_cached_objects(sb);
+ total_objects = sb->s_op->nr_cached_objects(sb,
+ &sc->nodes_to_scan);

- total_objects += list_lru_count(&sb->s_dentry_lru);
- total_objects += list_lru_count(&sb->s_inode_lru);
+ total_objects += list_lru_count_nodemask(&sb->s_dentry_lru,
+ &sc->nodes_to_scan);
+ total_objects += list_lru_count_nodemask(&sb->s_inode_lru,
+ &sc->nodes_to_scan);

total_objects = vfs_pressure_ratio(total_objects);
drop_super(sb);
diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
index 1ff991b..7fa60214 100644
--- a/fs/xfs/xfs_super.c
+++ b/fs/xfs/xfs_super.c
@@ -1525,7 +1525,8 @@ xfs_fs_mount(

static long
xfs_fs_nr_cached_objects(
- struct super_block *sb)
+ struct super_block *sb,
+ nodemask_t *nodes_to_count)
{
return xfs_reclaim_inodes_count(XFS_M(sb));
}
@@ -1533,7 +1534,8 @@ xfs_fs_nr_cached_objects(
static long
xfs_fs_free_cached_objects(
struct super_block *sb,
- long nr_to_scan)
+ long nr_to_scan,
+ nodemask_t *nodes_to_scan)
{
return xfs_reclaim_inodes_nr(XFS_M(sb), nr_to_scan);
}
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 02b3612..d548724 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1609,8 +1609,8 @@ struct super_operations {
ssize_t (*quota_write)(struct super_block *, int, const char *, size_t, loff_t);
#endif
int (*bdev_try_to_free_page)(struct super_block*, struct page*, gfp_t);
- long (*nr_cached_objects)(struct super_block *);
- long (*free_cached_objects)(struct super_block *, long);
+ long (*nr_cached_objects)(struct super_block *, nodemask_t *);
+ long (*free_cached_objects)(struct super_block *, long, nodemask_t *);
};

/*
diff --git a/include/linux/list_lru.h b/include/linux/list_lru.h
index 668f1f1..f5e3c15 100644
--- a/include/linux/list_lru.h
+++ b/include/linux/list_lru.h
@@ -42,15 +42,31 @@ struct list_lru {
int list_lru_init(struct list_lru *lru);
int list_lru_add(struct list_lru *lru, struct list_head *item);
int list_lru_del(struct list_lru *lru, struct list_head *item);
-unsigned long list_lru_count(struct list_lru *lru);
+unsigned long
+list_lru_count_nodemask(struct list_lru *lru, nodemask_t *nodes_to_count);
+
+static inline unsigned long list_lru_count(struct list_lru *lru)
+{
+ return list_lru_count_nodemask(lru, &lru->active_nodes);
+}
+

typedef enum lru_status
(*list_lru_walk_cb)(struct list_head *item, spinlock_t *lock, void *cb_arg);

typedef void (*list_lru_dispose_cb)(struct list_head *dispose_list);

-unsigned long list_lru_walk(struct list_lru *lru, list_lru_walk_cb isolate,
- void *cb_arg, unsigned long nr_to_walk);
+unsigned long
+list_lru_walk_nodemask(struct list_lru *lru, list_lru_walk_cb isolate,
+ void *cb_arg, unsigned long nr_to_walk, nodemask_t *nodes_to_walk);
+
+static inline unsigned long
+list_lru_walk(struct list_lru *lru, list_lru_walk_cb isolate,
+ void *cb_arg, unsigned long nr_to_walk)
+{
+ return list_lru_walk_nodemask(lru, isolate, cb_arg, nr_to_walk,
+ &lru->active_nodes);
+}

unsigned long
list_lru_dispose_all(struct list_lru *lru, list_lru_dispose_cb dispose);
diff --git a/lib/list_lru.c b/lib/list_lru.c
index 6d43079..248be3b 100644
--- a/lib/list_lru.c
+++ b/lib/list_lru.c
@@ -54,12 +54,12 @@ list_lru_del(
EXPORT_SYMBOL_GPL(list_lru_del);

unsigned long
-list_lru_count(struct list_lru *lru)
+list_lru_count_nodemask(struct list_lru *lru, nodemask_t *nodes_to_count)
{
long count = 0;
int nid;

- for_each_node_mask(nid, lru->active_nodes) {
+ for_each_node_mask(nid, *nodes_to_count) {
struct list_lru_node *nlru = &lru->node[nid];

spin_lock(&nlru->lock);
@@ -70,7 +70,7 @@ list_lru_count(struct list_lru *lru)

return count;
}
-EXPORT_SYMBOL_GPL(list_lru_count);
+EXPORT_SYMBOL_GPL(list_lru_count_nodemask);

static unsigned long
list_lru_walk_node(
@@ -119,16 +119,17 @@ restart:
}

unsigned long
-list_lru_walk(
+list_lru_walk_nodemask(
struct list_lru *lru,
list_lru_walk_cb isolate,
void *cb_arg,
- unsigned long nr_to_walk)
+ unsigned long nr_to_walk,
+ nodemask_t *nodes_to_walk)
{
long isolated = 0;
int nid;

- for_each_node_mask(nid, lru->active_nodes) {
+ for_each_node_mask(nid, *nodes_to_walk) {
isolated += list_lru_walk_node(lru, nid, isolate,
cb_arg, &nr_to_walk);
if (nr_to_walk <= 0)
@@ -136,7 +137,7 @@ list_lru_walk(
}
return isolated;
}
-EXPORT_SYMBOL_GPL(list_lru_walk);
+EXPORT_SYMBOL_GPL(list_lru_walk_nodemask);

static unsigned long
list_lru_dispose_all_node(
--
1.8.1.4