[Ocfs2-devel] [PATCH 02/40] ocfs2: Change metadata caching locks to an operations structure.
Joel Becker
joel.becker at oracle.com
Fri Feb 13 14:15:49 PST 2009
We don't really want to cart around too many new fields on the
ocfs2_caching_info structure. So let's wrap all our access of the
parent object in a set of operations. One pointer on caching_info, and
more flexibility to boot.
Signed-off-by: Joel Becker <joel.becker at oracle.com>
---
fs/ocfs2/inode.c | 49 +++++++++++++++++++
fs/ocfs2/inode.h | 1 +
fs/ocfs2/ocfs2.h | 8 ++--
fs/ocfs2/super.c | 4 +-
fs/ocfs2/uptodate.c | 129 +++++++++++++++++++++++++++++++++-----------------
fs/ocfs2/uptodate.h | 30 +++++++++++-
6 files changed, 169 insertions(+), 52 deletions(-)
diff --git a/fs/ocfs2/inode.c b/fs/ocfs2/inode.c
index 5a89c3d..8e764b2 100644
--- a/fs/ocfs2/inode.c
+++ b/fs/ocfs2/inode.c
@@ -1346,3 +1346,52 @@ int ocfs2_read_inode_block(struct inode *inode, struct buffer_head **bh)
{
return ocfs2_read_inode_block_full(inode, bh, 0);
}
+
+static struct ocfs2_inode_info *cache_info_to_inode(struct ocfs2_caching_info *ci)
+{
+ return container_of(ci, struct ocfs2_inode_info, ip_metadata_cache);
+}
+
+static u64 ocfs2_inode_cache_owner(struct ocfs2_caching_info *ci)
+{
+ struct ocfs2_inode_info *oi = cache_info_to_inode(ci);
+
+ return oi->ip_blkno;
+}
+
+static void ocfs2_inode_cache_lock(struct ocfs2_caching_info *ci)
+{
+ struct ocfs2_inode_info *oi = cache_info_to_inode(ci);
+
+ spin_lock(&oi->ip_lock);
+}
+
+static void ocfs2_inode_cache_unlock(struct ocfs2_caching_info *ci)
+{
+ struct ocfs2_inode_info *oi = cache_info_to_inode(ci);
+
+ spin_unlock(&oi->ip_lock);
+}
+
+static void ocfs2_inode_cache_io_lock(struct ocfs2_caching_info *ci)
+{
+ struct ocfs2_inode_info *oi = cache_info_to_inode(ci);
+
+ mutex_lock(&oi->ip_io_mutex);
+}
+
+static void ocfs2_inode_cache_io_unlock(struct ocfs2_caching_info *ci)
+{
+ struct ocfs2_inode_info *oi = cache_info_to_inode(ci);
+
+ mutex_unlock(&oi->ip_io_mutex);
+}
+
+const struct ocfs2_caching_operations ocfs2_inode_caching_ops = {
+ .co_owner = ocfs2_inode_cache_owner,
+ .co_cache_lock = ocfs2_inode_cache_lock,
+ .co_cache_unlock = ocfs2_inode_cache_unlock,
+ .co_io_lock = ocfs2_inode_cache_io_lock,
+ .co_io_unlock = ocfs2_inode_cache_io_unlock,
+};
+
diff --git a/fs/ocfs2/inode.h b/fs/ocfs2/inode.h
index 84191b1..6255a6c 100644
--- a/fs/ocfs2/inode.h
+++ b/fs/ocfs2/inode.h
@@ -114,6 +114,7 @@ static inline struct ocfs2_inode_info *OCFS2_I(struct inode *inode)
extern struct kmem_cache *ocfs2_inode_cache;
extern const struct address_space_operations ocfs2_aops;
+extern const struct ocfs2_caching_operations ocfs2_inode_caching_ops;
void ocfs2_clear_inode(struct inode *inode);
void ocfs2_delete_inode(struct inode *inode);
diff --git a/fs/ocfs2/ocfs2.h b/fs/ocfs2/ocfs2.h
index b36d961..166b8be 100644
--- a/fs/ocfs2/ocfs2.h
+++ b/fs/ocfs2/ocfs2.h
@@ -64,14 +64,14 @@ enum ocfs2_caching_info_flags {
OCFS2_CACHE_FL_INLINE = 1<<1,
};
+struct ocfs2_caching_operations;
struct ocfs2_caching_info {
/*
* The parent structure provides the locks, but because the
- * parent structure can differ, struct ocfs2_caching_info needs
- * its own pointers to them.
+ * parent structure can differ, it provides locking operations
+ * to struct ocfs2_caching_info.
*/
- spinlock_t *ci_lock;
- struct mutex *ci_io_mutex;
+ const struct ocfs2_caching_operations *ci_ops;
unsigned int ci_flags;
unsigned int ci_num_cached;
diff --git a/fs/ocfs2/super.c b/fs/ocfs2/super.c
index b10e3ca..536994d 100644
--- a/fs/ocfs2/super.c
+++ b/fs/ocfs2/super.c
@@ -1463,8 +1463,8 @@ static void ocfs2_inode_init_once(void *data)
ocfs2_lock_res_init_once(&oi->ip_inode_lockres);
ocfs2_lock_res_init_once(&oi->ip_open_lockres);
- ocfs2_metadata_cache_init(&oi->ip_metadata_cache, &oi->ip_lock,
- &oi->ip_io_mutex);
+ ocfs2_metadata_cache_init(&oi->ip_metadata_cache,
+ &ocfs2_inode_caching_ops);
inode_init_once(&oi->vfs_inode);
}
diff --git a/fs/ocfs2/uptodate.c b/fs/ocfs2/uptodate.c
index 8dbc457..226d042 100644
--- a/fs/ocfs2/uptodate.c
+++ b/fs/ocfs2/uptodate.c
@@ -75,12 +75,48 @@ struct ocfs2_meta_cache_item {
static struct kmem_cache *ocfs2_uptodate_cachep = NULL;
+static u64 ocfs2_metadata_cache_owner(struct ocfs2_caching_info *ci)
+{
+ BUG_ON(!ci || !ci->ci_ops);
+
+ return ci->ci_ops->co_owner(ci);
+}
+
+static void ocfs2_metadata_cache_lock(struct ocfs2_caching_info *ci)
+{
+ BUG_ON(!ci || !ci->ci_ops);
+
+ ci->ci_ops->co_cache_lock(ci);
+}
+
+static void ocfs2_metadata_cache_unlock(struct ocfs2_caching_info *ci)
+{
+ BUG_ON(!ci || !ci->ci_ops);
+
+ ci->ci_ops->co_cache_unlock(ci);
+}
+
+static void ocfs2_metadata_cache_io_lock(struct ocfs2_caching_info *ci)
+{
+ BUG_ON(!ci || !ci->ci_ops);
+
+ ci->ci_ops->co_io_lock(ci);
+}
+
+static void ocfs2_metadata_cache_io_unlock(struct ocfs2_caching_info *ci)
+{
+ BUG_ON(!ci || !ci->ci_ops);
+
+ ci->ci_ops->co_io_unlock(ci);
+}
+
+
void ocfs2_metadata_cache_init(struct ocfs2_caching_info *ci,
- spinlock_t *cache_lock,
- struct mutex *io_mutex)
+ const struct ocfs2_caching_operations *ops)
{
- ci->ci_lock = cache_lock;
- ci->ci_io_mutex = io_mutex;
+ BUG_ON(!ops);
+
+ ci->ci_ops = ops;
ci->ci_flags |= OCFS2_CACHE_FL_INLINE;
ci->ci_num_cached = 0;
}
@@ -120,12 +156,15 @@ void ocfs2_metadata_cache_purge(struct inode *inode)
struct ocfs2_caching_info *ci = &oi->ip_metadata_cache;
struct rb_root root = RB_ROOT;
- spin_lock(ci->ci_lock);
+ BUG_ON(!ci || !ci->ci_ops);
+
+ ocfs2_metadata_cache_lock(ci);
tree = !(ci->ci_flags & OCFS2_CACHE_FL_INLINE);
to_purge = ci->ci_num_cached;
- mlog(0, "Purge %u %s items from Inode %llu\n", to_purge,
- tree ? "array" : "tree", (unsigned long long)oi->ip_blkno);
+ mlog(0, "Purge %u %s items from Owner %llu\n", to_purge,
+ tree ? "array" : "tree",
+ (unsigned long long)ocfs2_metadata_cache_owner(ci));
/* If we're a tree, save off the root so that we can safely
* initialize the cache. We do the work to free tree members
@@ -133,16 +172,17 @@ void ocfs2_metadata_cache_purge(struct inode *inode)
if (tree)
root = ci->ci_cache.ci_tree;
- ocfs2_metadata_cache_init(ci, ci->ci_lock, ci->ci_io_mutex);
- spin_unlock(ci->ci_lock);
+ ocfs2_metadata_cache_init(ci, ci->ci_ops);
+ ocfs2_metadata_cache_unlock(ci);
purged = ocfs2_purge_copied_metadata_tree(&root);
/* If possible, track the number wiped so that we can more
* easily detect counting errors. Unfortunately, this is only
* meaningful for trees. */
if (tree && purged != to_purge)
- mlog(ML_ERROR, "Inode %llu, count = %u, purged = %u\n",
- (unsigned long long)oi->ip_blkno, to_purge, purged);
+ mlog(ML_ERROR, "Owner %llu, count = %u, purged = %u\n",
+ (unsigned long long)ocfs2_metadata_cache_owner(ci),
+ to_purge, purged);
}
/* Returns the index in the cache array, -1 if not found.
@@ -190,10 +230,10 @@ static int ocfs2_buffer_cached(struct ocfs2_inode_info *oi,
struct ocfs2_meta_cache_item *item = NULL;
struct ocfs2_caching_info *ci = &oi->ip_metadata_cache;
- spin_lock(ci->ci_lock);
+ ocfs2_metadata_cache_lock(ci);
- mlog(0, "Inode %llu, query block %llu (inline = %u)\n",
- (unsigned long long)oi->ip_blkno,
+ mlog(0, "Owner %llu, query block %llu (inline = %u)\n",
+ (unsigned long long)ocfs2_metadata_cache_owner(ci),
(unsigned long long) bh->b_blocknr,
!!(ci->ci_flags & OCFS2_CACHE_FL_INLINE));
@@ -204,7 +244,7 @@ static int ocfs2_buffer_cached(struct ocfs2_inode_info *oi,
item = ocfs2_search_cache_tree(&oi->ip_metadata_cache,
bh->b_blocknr);
- spin_unlock(ci->ci_lock);
+ ocfs2_metadata_cache_unlock(ci);
mlog(0, "index = %d, item = %p\n", index, item);
@@ -294,18 +334,19 @@ static void __ocfs2_insert_cache_tree(struct ocfs2_caching_info *ci,
ci->ci_num_cached++;
}
+/* co_cache_lock() must be held */
static inline int ocfs2_insert_can_use_array(struct ocfs2_inode_info *oi,
struct ocfs2_caching_info *ci)
{
- assert_spin_locked(ci->ci_lock);
-
return (ci->ci_flags & OCFS2_CACHE_FL_INLINE) &&
(ci->ci_num_cached < OCFS2_CACHE_INFO_MAX_ARRAY);
}
/* tree should be exactly OCFS2_CACHE_INFO_MAX_ARRAY wide. NULL the
* pointers in tree after we use them - this allows caller to detect
- * when to free in case of error. */
+ * when to free in case of error.
+ *
+ * The co_cache_lock() must be held. */
static void ocfs2_expand_cache(struct ocfs2_inode_info *oi,
struct ocfs2_meta_cache_item **tree)
{
@@ -313,13 +354,12 @@ static void ocfs2_expand_cache(struct ocfs2_inode_info *oi,
struct ocfs2_caching_info *ci = &oi->ip_metadata_cache;
mlog_bug_on_msg(ci->ci_num_cached != OCFS2_CACHE_INFO_MAX_ARRAY,
- "Inode %llu, num cached = %u, should be %u\n",
- (unsigned long long)oi->ip_blkno, ci->ci_num_cached,
- OCFS2_CACHE_INFO_MAX_ARRAY);
+ "Owner %llu, num cached = %u, should be %u\n",
+ (unsigned long long)ocfs2_metadata_cache_owner(ci),
+ ci->ci_num_cached, OCFS2_CACHE_INFO_MAX_ARRAY);
mlog_bug_on_msg(!(ci->ci_flags & OCFS2_CACHE_FL_INLINE),
- "Inode %llu not marked as inline anymore!\n",
- (unsigned long long)oi->ip_blkno);
- assert_spin_locked(ci->ci_lock);
+ "Owner %llu not marked as inline anymore!\n",
+ (unsigned long long)ocfs2_metadata_cache_owner(ci));
/* Be careful to initialize the tree members *first* because
* once the ci_tree is used, the array is junk... */
@@ -337,7 +377,8 @@ static void ocfs2_expand_cache(struct ocfs2_inode_info *oi,
}
mlog(0, "Expanded %llu to a tree cache: flags 0x%x, num = %u\n",
- (unsigned long long)oi->ip_blkno, ci->ci_flags, ci->ci_num_cached);
+ (unsigned long long)ocfs2_metadata_cache_owner(ci),
+ ci->ci_flags, ci->ci_num_cached);
}
/* Slow path function - memory allocation is necessary. See the
@@ -352,8 +393,8 @@ static void __ocfs2_set_buffer_uptodate(struct ocfs2_inode_info *oi,
struct ocfs2_meta_cache_item *tree[OCFS2_CACHE_INFO_MAX_ARRAY] =
{ NULL, };
- mlog(0, "Inode %llu, block %llu, expand = %d\n",
- (unsigned long long)oi->ip_blkno,
+ mlog(0, "Owner %llu, block %llu, expand = %d\n",
+ (unsigned long long)ocfs2_metadata_cache_owner(ci),
(unsigned long long)block, expand_tree);
new = kmem_cache_alloc(ocfs2_uptodate_cachep, GFP_NOFS);
@@ -378,13 +419,13 @@ static void __ocfs2_set_buffer_uptodate(struct ocfs2_inode_info *oi,
}
}
- spin_lock(ci->ci_lock);
+ ocfs2_metadata_cache_lock(ci);
if (ocfs2_insert_can_use_array(oi, ci)) {
mlog(0, "Someone cleared the tree underneath us\n");
/* Ok, items were removed from the cache in between
* locks. Detect this and revert back to the fast path */
ocfs2_append_cache_array(ci, block);
- spin_unlock(ci->ci_lock);
+ ocfs2_metadata_cache_unlock(ci);
goto out_free;
}
@@ -392,7 +433,7 @@ static void __ocfs2_set_buffer_uptodate(struct ocfs2_inode_info *oi,
ocfs2_expand_cache(oi, tree);
__ocfs2_insert_cache_tree(ci, new);
- spin_unlock(ci->ci_lock);
+ ocfs2_metadata_cache_unlock(ci);
new = NULL;
out_free:
@@ -409,7 +450,7 @@ out_free:
}
}
-/* Item insertion is guarded by ci_io_mutex, so the insertion path takes
+/* Item insertion is guarded by co_io_lock(), so the insertion path takes
* advantage of this by not rechecking for a duplicate insert during
* the slow case. Additionally, if the cache needs to be bumped up to
* a tree, the code will not recheck after acquiring the lock --
@@ -439,18 +480,18 @@ void ocfs2_set_buffer_uptodate(struct inode *inode,
if (ocfs2_buffer_cached(oi, bh))
return;
- mlog(0, "Inode %llu, inserting block %llu\n",
- (unsigned long long)oi->ip_blkno,
+ mlog(0, "Owner %llu, inserting block %llu\n",
+ (unsigned long long)ocfs2_metadata_cache_owner(ci),
(unsigned long long)bh->b_blocknr);
/* No need to recheck under spinlock - insertion is guarded by
- * ci_io_mutex */
- spin_lock(ci->ci_lock);
+ * co_io_lock() */
+ ocfs2_metadata_cache_lock(ci);
if (ocfs2_insert_can_use_array(oi, ci)) {
/* Fast case - it's an array and there's a free
* spot. */
ocfs2_append_cache_array(ci, bh->b_blocknr);
- spin_unlock(ci->ci_lock);
+ ocfs2_metadata_cache_unlock(ci);
return;
}
@@ -459,14 +500,14 @@ void ocfs2_set_buffer_uptodate(struct inode *inode,
/* We need to bump things up to a tree. */
expand = 1;
}
- spin_unlock(ci->ci_lock);
+ ocfs2_metadata_cache_unlock(ci);
__ocfs2_set_buffer_uptodate(oi, bh->b_blocknr, expand);
}
/* Called against a newly allocated buffer. Most likely nobody should
* be able to read this sort of metadata while it's still being
- * allocated, but this is careful to take ci_io_mutex anyway. */
+ * allocated, but this is careful to take co_io_lock() anyway. */
void ocfs2_set_new_buffer_uptodate(struct inode *inode,
struct buffer_head *bh)
{
@@ -478,9 +519,9 @@ void ocfs2_set_new_buffer_uptodate(struct inode *inode,
set_buffer_uptodate(bh);
- mutex_lock(ci->ci_io_mutex);
+ ocfs2_metadata_cache_io_lock(ci);
ocfs2_set_buffer_uptodate(inode, bh);
- mutex_unlock(ci->ci_io_mutex);
+ ocfs2_metadata_cache_io_unlock(ci);
}
/* Requires ip_lock. */
@@ -526,9 +567,9 @@ static void ocfs2_remove_block_from_cache(struct inode *inode,
struct ocfs2_inode_info *oi = OCFS2_I(inode);
struct ocfs2_caching_info *ci = &oi->ip_metadata_cache;
- spin_lock(ci->ci_lock);
- mlog(0, "Inode %llu, remove %llu, items = %u, array = %u\n",
- (unsigned long long)oi->ip_blkno,
+ ocfs2_metadata_cache_lock(ci);
+ mlog(0, "Owner %llu, remove %llu, items = %u, array = %u\n",
+ (unsigned long long)ocfs2_metadata_cache_owner(ci),
(unsigned long long) block, ci->ci_num_cached,
ci->ci_flags & OCFS2_CACHE_FL_INLINE);
@@ -541,7 +582,7 @@ static void ocfs2_remove_block_from_cache(struct inode *inode,
if (item)
ocfs2_remove_metadata_tree(ci, item);
}
- spin_unlock(ci->ci_lock);
+ ocfs2_metadata_cache_unlock(ci);
if (item)
kmem_cache_free(ocfs2_uptodate_cachep, item);
diff --git a/fs/ocfs2/uptodate.h b/fs/ocfs2/uptodate.h
index bd749e1..3b33eb8 100644
--- a/fs/ocfs2/uptodate.h
+++ b/fs/ocfs2/uptodate.h
@@ -26,12 +26,38 @@
#ifndef OCFS2_UPTODATE_H
#define OCFS2_UPTODATE_H
+/*
+ * The caching code relies on locking provided by the user of
+ * struct ocfs2_caching_info. These operations connect that up.
+ */
+struct ocfs2_caching_operations {
+ /*
+ * A u64 representing the owning structure. Usually this
+ * is the block number (i_blkno or whatnot). This is used so
+ * that caching log messages can identify the owning structure.
+ */
+ u64 (*co_owner)(struct ocfs2_caching_info *ci);
+
+ /*
+ * Lock and unlock the caching data. These will not sleep, and
+ * should probably be spinlocks.
+ */
+ void (*co_cache_lock)(struct ocfs2_caching_info *ci);
+ void (*co_cache_unlock)(struct ocfs2_caching_info *ci);
+
+ /*
+ * Lock and unlock for disk I/O. These will sleep, and should
+ * be mutexes.
+ */
+ void (*co_io_lock)(struct ocfs2_caching_info *ci);
+ void (*co_io_unlock)(struct ocfs2_caching_info *ci);
+};
+
int __init init_ocfs2_uptodate_cache(void);
void exit_ocfs2_uptodate_cache(void);
void ocfs2_metadata_cache_init(struct ocfs2_caching_info *ci,
- spinlock_t *cache_lock,
- struct mutex *io_mutex);
+ const struct ocfs2_caching_operations *ops);
void ocfs2_metadata_cache_purge(struct inode *inode);
int ocfs2_buffer_uptodate(struct inode *inode,
--
1.5.6.5
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