[PATCH] jbd/jbd2: JBD memory allocation cleanups

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From: Mingming Cao <[email protected]>

JBD: Replace slab allocations with page cache allocations

JBD allocate memory for committed_data and frozen_data from slab. However
JBD should not pass slab pages down to the block layer. Use page allocator pages instead. This will also prepare JBD for the large blocksize patchset.


Also this patch cleans up jbd_kmalloc and replace it with kmalloc directly

Signed-off-by: Christoph Lameter <[email protected]>
Signed-off-by: Mingming Cao <[email protected]>
---
 fs/jbd/commit.c       |    6 +-
 fs/jbd/journal.c      |   99 ++----------------------------------------------
 fs/jbd/transaction.c  |   12 +++---
 fs/jbd2/commit.c      |    6 +-
 fs/jbd2/journal.c     |   99 ++----------------------------------------------
 fs/jbd2/transaction.c |   18 ++++----
 include/linux/jbd.h   |   18 +++++----
 include/linux/jbd2.h  |   19 +++++----
 8 files changed, 51 insertions(+), 226 deletions(-)

diff --git a/fs/jbd/commit.c b/fs/jbd/commit.c
index a003d50..a263d82 100644
--- a/fs/jbd/commit.c
+++ b/fs/jbd/commit.c
@@ -375,7 +375,7 @@ void journal_commit_transaction(journal_t *journal)
 			struct buffer_head *bh = jh2bh(jh);
 
 			jbd_lock_bh_state(bh);
-			jbd_slab_free(jh->b_committed_data, bh->b_size);
+			jbd_free(jh->b_committed_data, bh->b_size);
 			jh->b_committed_data = NULL;
 			jbd_unlock_bh_state(bh);
 		}
@@ -792,14 +792,14 @@ restart_loop:
 		 * Otherwise, we can just throw away the frozen data now.
 		 */
 		if (jh->b_committed_data) {
-			jbd_slab_free(jh->b_committed_data, bh->b_size);
+			jbd_free(jh->b_committed_data, bh->b_size);
 			jh->b_committed_data = NULL;
 			if (jh->b_frozen_data) {
 				jh->b_committed_data = jh->b_frozen_data;
 				jh->b_frozen_data = NULL;
 			}
 		} else if (jh->b_frozen_data) {
-			jbd_slab_free(jh->b_frozen_data, bh->b_size);
+			jbd_free(jh->b_frozen_data, bh->b_size);
 			jh->b_frozen_data = NULL;
 		}
 
diff --git a/fs/jbd/journal.c b/fs/jbd/journal.c
index 06ab3c1..ae2c25d 100644
--- a/fs/jbd/journal.c
+++ b/fs/jbd/journal.c
@@ -83,7 +83,6 @@ EXPORT_SYMBOL(journal_force_commit);
 
 static int journal_convert_superblock_v1(journal_t *, journal_superblock_t *);
 static void __journal_abort_soft (journal_t *journal, int errno);
-static int journal_create_jbd_slab(size_t slab_size);
 
 /*
  * Helper function used to manage commit timeouts
@@ -334,10 +333,10 @@ repeat:
 		char *tmp;
 
 		jbd_unlock_bh_state(bh_in);
-		tmp = jbd_slab_alloc(bh_in->b_size, GFP_NOFS);
+		tmp = jbd_alloc(bh_in->b_size, GFP_NOFS);
 		jbd_lock_bh_state(bh_in);
 		if (jh_in->b_frozen_data) {
-			jbd_slab_free(tmp, bh_in->b_size);
+			jbd_free(tmp, bh_in->b_size);
 			goto repeat;
 		}
 
@@ -654,7 +653,7 @@ static journal_t * journal_init_common (void)
 	journal_t *journal;
 	int err;
 
-	journal = jbd_kmalloc(sizeof(*journal), GFP_KERNEL);
+	journal = kmalloc(sizeof(*journal), GFP_KERNEL|__GFP_NOFAIL);
 	if (!journal)
 		goto fail;
 	memset(journal, 0, sizeof(*journal));
@@ -1095,13 +1094,6 @@ int journal_load(journal_t *journal)
 		}
 	}
 
-	/*
-	 * Create a slab for this blocksize
-	 */
-	err = journal_create_jbd_slab(be32_to_cpu(sb->s_blocksize));
-	if (err)
-		return err;
-
 	/* Let the recovery code check whether it needs to recover any
 	 * data from the journal. */
 	if (journal_recover(journal))
@@ -1615,86 +1607,6 @@ int journal_blocks_per_page(struct inode *inode)
 }
 
 /*
- * Simple support for retrying memory allocations.  Introduced to help to
- * debug different VM deadlock avoidance strategies.
- */
-void * __jbd_kmalloc (const char *where, size_t size, gfp_t flags, int retry)
-{
-	return kmalloc(size, flags | (retry ? __GFP_NOFAIL : 0));
-}
-
-/*
- * jbd slab management: create 1k, 2k, 4k, 8k slabs as needed
- * and allocate frozen and commit buffers from these slabs.
- *
- * Reason for doing this is to avoid, SLAB_DEBUG - since it could
- * cause bh to cross page boundary.
- */
-
-#define JBD_MAX_SLABS 5
-#define JBD_SLAB_INDEX(size)  (size >> 11)
-
-static struct kmem_cache *jbd_slab[JBD_MAX_SLABS];
-static const char *jbd_slab_names[JBD_MAX_SLABS] = {
-	"jbd_1k", "jbd_2k", "jbd_4k", NULL, "jbd_8k"
-};
-
-static void journal_destroy_jbd_slabs(void)
-{
-	int i;
-
-	for (i = 0; i < JBD_MAX_SLABS; i++) {
-		if (jbd_slab[i])
-			kmem_cache_destroy(jbd_slab[i]);
-		jbd_slab[i] = NULL;
-	}
-}
-
-static int journal_create_jbd_slab(size_t slab_size)
-{
-	int i = JBD_SLAB_INDEX(slab_size);
-
-	BUG_ON(i >= JBD_MAX_SLABS);
-
-	/*
-	 * Check if we already have a slab created for this size
-	 */
-	if (jbd_slab[i])
-		return 0;
-
-	/*
-	 * Create a slab and force alignment to be same as slabsize -
-	 * this will make sure that allocations won't cross the page
-	 * boundary.
-	 */
-	jbd_slab[i] = kmem_cache_create(jbd_slab_names[i],
-				slab_size, slab_size, 0, NULL);
-	if (!jbd_slab[i]) {
-		printk(KERN_EMERG "JBD: no memory for jbd_slab cache\n");
-		return -ENOMEM;
-	}
-	return 0;
-}
-
-void * jbd_slab_alloc(size_t size, gfp_t flags)
-{
-	int idx;
-
-	idx = JBD_SLAB_INDEX(size);
-	BUG_ON(jbd_slab[idx] == NULL);
-	return kmem_cache_alloc(jbd_slab[idx], flags | __GFP_NOFAIL);
-}
-
-void jbd_slab_free(void *ptr,  size_t size)
-{
-	int idx;
-
-	idx = JBD_SLAB_INDEX(size);
-	BUG_ON(jbd_slab[idx] == NULL);
-	kmem_cache_free(jbd_slab[idx], ptr);
-}
-
-/*
  * Journal_head storage management
  */
 static struct kmem_cache *journal_head_cache;
@@ -1881,13 +1793,13 @@ static void __journal_remove_journal_head(struct buffer_head *bh)
 				printk(KERN_WARNING "%s: freeing "
 						"b_frozen_data\n",
 						__FUNCTION__);
-				jbd_slab_free(jh->b_frozen_data, bh->b_size);
+				jbd_free(jh->b_frozen_data, bh->b_size);
 			}
 			if (jh->b_committed_data) {
 				printk(KERN_WARNING "%s: freeing "
 						"b_committed_data\n",
 						__FUNCTION__);
-				jbd_slab_free(jh->b_committed_data, bh->b_size);
+				jbd_free(jh->b_committed_data, bh->b_size);
 			}
 			bh->b_private = NULL;
 			jh->b_bh = NULL;	/* debug, really */
@@ -2042,7 +1954,6 @@ static void journal_destroy_caches(void)
 	journal_destroy_revoke_caches();
 	journal_destroy_journal_head_cache();
 	journal_destroy_handle_cache();
-	journal_destroy_jbd_slabs();
 }
 
 static int __init journal_init(void)
diff --git a/fs/jbd/transaction.c b/fs/jbd/transaction.c
index 772b653..11d846c 100644
--- a/fs/jbd/transaction.c
+++ b/fs/jbd/transaction.c
@@ -96,8 +96,8 @@ static int start_this_handle(journal_t *journal, handle_t *handle)
 
 alloc_transaction:
 	if (!journal->j_running_transaction) {
-		new_transaction = jbd_kmalloc(sizeof(*new_transaction),
-						GFP_NOFS);
+		new_transaction = kmalloc(sizeof(*new_transaction),
+						GFP_NOFS|__GFP_NOFAIL);
 		if (!new_transaction) {
 			ret = -ENOMEM;
 			goto out;
@@ -668,7 +668,7 @@ repeat:
 				JBUFFER_TRACE(jh, "allocate memory for buffer");
 				jbd_unlock_bh_state(bh);
 				frozen_buffer =
-					jbd_slab_alloc(jh2bh(jh)->b_size,
+					jbd_alloc(jh2bh(jh)->b_size,
 							 GFP_NOFS);
 				if (!frozen_buffer) {
 					printk(KERN_EMERG
@@ -728,7 +728,7 @@ done:
 
 out:
 	if (unlikely(frozen_buffer))	/* It's usually NULL */
-		jbd_slab_free(frozen_buffer, bh->b_size);
+		jbd_free(frozen_buffer, bh->b_size);
 
 	JBUFFER_TRACE(jh, "exit");
 	return error;
@@ -881,7 +881,7 @@ int journal_get_undo_access(handle_t *handle, struct buffer_head *bh)
 
 repeat:
 	if (!jh->b_committed_data) {
-		committed_data = jbd_slab_alloc(jh2bh(jh)->b_size, GFP_NOFS);
+		committed_data = jbd_alloc(jh2bh(jh)->b_size, GFP_NOFS);
 		if (!committed_data) {
 			printk(KERN_EMERG "%s: No memory for committed data\n",
 				__FUNCTION__);
@@ -908,7 +908,7 @@ repeat:
 out:
 	journal_put_journal_head(jh);
 	if (unlikely(committed_data))
-		jbd_slab_free(committed_data, bh->b_size);
+		jbd_free(committed_data, bh->b_size);
 	return err;
 }
 
diff --git a/fs/jbd2/commit.c b/fs/jbd2/commit.c
index c0f59d1..2cac34a 100644
--- a/fs/jbd2/commit.c
+++ b/fs/jbd2/commit.c
@@ -384,7 +384,7 @@ void jbd2_journal_commit_transaction(journal_t *journal)
 			struct buffer_head *bh = jh2bh(jh);
 
 			jbd_lock_bh_state(bh);
-			jbd2_slab_free(jh->b_committed_data, bh->b_size);
+			jbd2_free(jh->b_committed_data, bh->b_size);
 			jh->b_committed_data = NULL;
 			jbd_unlock_bh_state(bh);
 		}
@@ -801,14 +801,14 @@ restart_loop:
 		 * Otherwise, we can just throw away the frozen data now.
 		 */
 		if (jh->b_committed_data) {
-			jbd2_slab_free(jh->b_committed_data, bh->b_size);
+			jbd2_free(jh->b_committed_data, bh->b_size);
 			jh->b_committed_data = NULL;
 			if (jh->b_frozen_data) {
 				jh->b_committed_data = jh->b_frozen_data;
 				jh->b_frozen_data = NULL;
 			}
 		} else if (jh->b_frozen_data) {
-			jbd2_slab_free(jh->b_frozen_data, bh->b_size);
+			jbd2_free(jh->b_frozen_data, bh->b_size);
 			jh->b_frozen_data = NULL;
 		}
 
diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c
index f37324a..4281244 100644
--- a/fs/jbd2/journal.c
+++ b/fs/jbd2/journal.c
@@ -84,7 +84,6 @@ EXPORT_SYMBOL(jbd2_journal_force_commit);
 
 static int journal_convert_superblock_v1(journal_t *, journal_superblock_t *);
 static void __journal_abort_soft (journal_t *journal, int errno);
-static int jbd2_journal_create_jbd_slab(size_t slab_size);
 
 /*
  * Helper function used to manage commit timeouts
@@ -335,10 +334,10 @@ repeat:
 		char *tmp;
 
 		jbd_unlock_bh_state(bh_in);
-		tmp = jbd2_slab_alloc(bh_in->b_size, GFP_NOFS);
+		tmp = jbd2_alloc(bh_in->b_size, GFP_NOFS);
 		jbd_lock_bh_state(bh_in);
 		if (jh_in->b_frozen_data) {
-			jbd2_slab_free(tmp, bh_in->b_size);
+			jbd2_free(tmp, bh_in->b_size);
 			goto repeat;
 		}
 
@@ -655,7 +654,7 @@ static journal_t * journal_init_common (void)
 	journal_t *journal;
 	int err;
 
-	journal = jbd_kmalloc(sizeof(*journal), GFP_KERNEL);
+	journal = kmalloc(sizeof(*journal), GFP_KERNEL|__GFP_NOFAIL);
 	if (!journal)
 		goto fail;
 	memset(journal, 0, sizeof(*journal));
@@ -1096,13 +1095,6 @@ int jbd2_journal_load(journal_t *journal)
 		}
 	}
 
-	/*
-	 * Create a slab for this blocksize
-	 */
-	err = jbd2_journal_create_jbd_slab(be32_to_cpu(sb->s_blocksize));
-	if (err)
-		return err;
-
 	/* Let the recovery code check whether it needs to recover any
 	 * data from the journal. */
 	if (jbd2_journal_recover(journal))
@@ -1627,86 +1619,6 @@ size_t journal_tag_bytes(journal_t *journal)
 }
 
 /*
- * Simple support for retrying memory allocations.  Introduced to help to
- * debug different VM deadlock avoidance strategies.
- */
-void * __jbd2_kmalloc (const char *where, size_t size, gfp_t flags, int retry)
-{
-	return kmalloc(size, flags | (retry ? __GFP_NOFAIL : 0));
-}
-
-/*
- * jbd slab management: create 1k, 2k, 4k, 8k slabs as needed
- * and allocate frozen and commit buffers from these slabs.
- *
- * Reason for doing this is to avoid, SLAB_DEBUG - since it could
- * cause bh to cross page boundary.
- */
-
-#define JBD_MAX_SLABS 5
-#define JBD_SLAB_INDEX(size)  (size >> 11)
-
-static struct kmem_cache *jbd_slab[JBD_MAX_SLABS];
-static const char *jbd_slab_names[JBD_MAX_SLABS] = {
-	"jbd2_1k", "jbd2_2k", "jbd2_4k", NULL, "jbd2_8k"
-};
-
-static void jbd2_journal_destroy_jbd_slabs(void)
-{
-	int i;
-
-	for (i = 0; i < JBD_MAX_SLABS; i++) {
-		if (jbd_slab[i])
-			kmem_cache_destroy(jbd_slab[i]);
-		jbd_slab[i] = NULL;
-	}
-}
-
-static int jbd2_journal_create_jbd_slab(size_t slab_size)
-{
-	int i = JBD_SLAB_INDEX(slab_size);
-
-	BUG_ON(i >= JBD_MAX_SLABS);
-
-	/*
-	 * Check if we already have a slab created for this size
-	 */
-	if (jbd_slab[i])
-		return 0;
-
-	/*
-	 * Create a slab and force alignment to be same as slabsize -
-	 * this will make sure that allocations won't cross the page
-	 * boundary.
-	 */
-	jbd_slab[i] = kmem_cache_create(jbd_slab_names[i],
-				slab_size, slab_size, 0, NULL);
-	if (!jbd_slab[i]) {
-		printk(KERN_EMERG "JBD: no memory for jbd_slab cache\n");
-		return -ENOMEM;
-	}
-	return 0;
-}
-
-void * jbd2_slab_alloc(size_t size, gfp_t flags)
-{
-	int idx;
-
-	idx = JBD_SLAB_INDEX(size);
-	BUG_ON(jbd_slab[idx] == NULL);
-	return kmem_cache_alloc(jbd_slab[idx], flags | __GFP_NOFAIL);
-}
-
-void jbd2_slab_free(void *ptr,  size_t size)
-{
-	int idx;
-
-	idx = JBD_SLAB_INDEX(size);
-	BUG_ON(jbd_slab[idx] == NULL);
-	kmem_cache_free(jbd_slab[idx], ptr);
-}
-
-/*
  * Journal_head storage management
  */
 static struct kmem_cache *jbd2_journal_head_cache;
@@ -1893,13 +1805,13 @@ static void __journal_remove_journal_head(struct buffer_head *bh)
 				printk(KERN_WARNING "%s: freeing "
 						"b_frozen_data\n",
 						__FUNCTION__);
-				jbd2_slab_free(jh->b_frozen_data, bh->b_size);
+				jbd2_free(jh->b_frozen_data, bh->b_size);
 			}
 			if (jh->b_committed_data) {
 				printk(KERN_WARNING "%s: freeing "
 						"b_committed_data\n",
 						__FUNCTION__);
-				jbd2_slab_free(jh->b_committed_data, bh->b_size);
+				jbd2_free(jh->b_committed_data, bh->b_size);
 			}
 			bh->b_private = NULL;
 			jh->b_bh = NULL;	/* debug, really */
@@ -2040,7 +1952,6 @@ static void jbd2_journal_destroy_caches(void)
 	jbd2_journal_destroy_revoke_caches();
 	jbd2_journal_destroy_jbd2_journal_head_cache();
 	jbd2_journal_destroy_handle_cache();
-	jbd2_journal_destroy_jbd_slabs();
 }
 
 static int __init journal_init(void)
diff --git a/fs/jbd2/transaction.c b/fs/jbd2/transaction.c
index 7946ff4..a5fb70f 100644
--- a/fs/jbd2/transaction.c
+++ b/fs/jbd2/transaction.c
@@ -96,8 +96,8 @@ static int start_this_handle(journal_t *journal, handle_t *handle)
 
 alloc_transaction:
 	if (!journal->j_running_transaction) {
-		new_transaction = jbd_kmalloc(sizeof(*new_transaction),
-						GFP_NOFS);
+		new_transaction = kmalloc(sizeof(*new_transaction),
+						GFP_NOFS|__GFP_NOFAIL);
 		if (!new_transaction) {
 			ret = -ENOMEM;
 			goto out;
@@ -236,7 +236,7 @@ out:
 /* Allocate a new handle.  This should probably be in a slab... */
 static handle_t *new_handle(int nblocks)
 {
-	handle_t *handle = jbd_alloc_handle(GFP_NOFS);
+	handle_t *handle = jbd2_alloc_handle(GFP_NOFS);
 	if (!handle)
 		return NULL;
 	memset(handle, 0, sizeof(*handle));
@@ -282,7 +282,7 @@ handle_t *jbd2_journal_start(journal_t *journal, int nblocks)
 
 	err = start_this_handle(journal, handle);
 	if (err < 0) {
-		jbd_free_handle(handle);
+		jbd2_free_handle(handle);
 		current->journal_info = NULL;
 		handle = ERR_PTR(err);
 	}
@@ -668,7 +668,7 @@ repeat:
 				JBUFFER_TRACE(jh, "allocate memory for buffer");
 				jbd_unlock_bh_state(bh);
 				frozen_buffer =
-					jbd2_slab_alloc(jh2bh(jh)->b_size,
+					jbd2_alloc(jh2bh(jh)->b_size,
 							 GFP_NOFS);
 				if (!frozen_buffer) {
 					printk(KERN_EMERG
@@ -728,7 +728,7 @@ done:
 
 out:
 	if (unlikely(frozen_buffer))	/* It's usually NULL */
-		jbd2_slab_free(frozen_buffer, bh->b_size);
+		jbd2_free(frozen_buffer, bh->b_size);
 
 	JBUFFER_TRACE(jh, "exit");
 	return error;
@@ -881,7 +881,7 @@ int jbd2_journal_get_undo_access(handle_t *handle, struct buffer_head *bh)
 
 repeat:
 	if (!jh->b_committed_data) {
-		committed_data = jbd2_slab_alloc(jh2bh(jh)->b_size, GFP_NOFS);
+		committed_data = jbd2_alloc(jh2bh(jh)->b_size, GFP_NOFS);
 		if (!committed_data) {
 			printk(KERN_EMERG "%s: No memory for committed data\n",
 				__FUNCTION__);
@@ -908,7 +908,7 @@ repeat:
 out:
 	jbd2_journal_put_journal_head(jh);
 	if (unlikely(committed_data))
-		jbd2_slab_free(committed_data, bh->b_size);
+		jbd2_free(committed_data, bh->b_size);
 	return err;
 }
 
@@ -1411,7 +1411,7 @@ int jbd2_journal_stop(handle_t *handle)
 		spin_unlock(&journal->j_state_lock);
 	}
 
-	jbd_free_handle(handle);
+	jbd2_free_handle(handle);
 	return err;
 }
 
diff --git a/include/linux/jbd.h b/include/linux/jbd.h
index 4527375..26216c1 100644
--- a/include/linux/jbd.h
+++ b/include/linux/jbd.h
@@ -71,14 +71,16 @@ extern int journal_enable_debug;
 #define jbd_debug(f, a...)	/**/
 #endif
 
-extern void * __jbd_kmalloc (const char *where, size_t size, gfp_t flags, int retry);
-extern void * jbd_slab_alloc(size_t size, gfp_t flags);
-extern void jbd_slab_free(void *ptr, size_t size);
-
-#define jbd_kmalloc(size, flags) \
-	__jbd_kmalloc(__FUNCTION__, (size), (flags), journal_oom_retry)
-#define jbd_rep_kmalloc(size, flags) \
-	__jbd_kmalloc(__FUNCTION__, (size), (flags), 1)
+
+static inline void *jbd_alloc(size_t size, gfp_t flags)
+{
+	return (void *)__get_free_pages(flags, get_order(size));
+}
+
+static inline void jbd_free(void *ptr, size_t size)
+{
+	free_pages((unsigned long)ptr, get_order(size));
+};
 
 #define JFS_MIN_JOURNAL_BLOCKS 1024
 
diff --git a/include/linux/jbd2.h b/include/linux/jbd2.h
index 260d6d7..5f8b876 100644
--- a/include/linux/jbd2.h
+++ b/include/linux/jbd2.h
@@ -71,14 +71,15 @@ extern u8 jbd2_journal_enable_debug;
 #define jbd_debug(f, a...)	/**/
 #endif
 
-extern void * __jbd2_kmalloc (const char *where, size_t size, gfp_t flags, int retry);
-extern void * jbd2_slab_alloc(size_t size, gfp_t flags);
-extern void jbd2_slab_free(void *ptr, size_t size);
+static inline void *jbd2_alloc(size_t size, gfp_t flags)
+{
+	return (void *)__get_free_pages(flags, get_order(size));
+}
 
-#define jbd_kmalloc(size, flags) \
-	__jbd2_kmalloc(__FUNCTION__, (size), (flags), journal_oom_retry)
-#define jbd_rep_kmalloc(size, flags) \
-	__jbd2_kmalloc(__FUNCTION__, (size), (flags), 1)
+static inline void jbd2_free(void *ptr, size_t size)
+{
+	free_pages((unsigned long)ptr, get_order(size));
+};
 
 #define JBD2_MIN_JOURNAL_BLOCKS 1024
 
@@ -959,12 +960,12 @@ void jbd2_journal_put_journal_head(struct journal_head *jh);
  */
 extern struct kmem_cache *jbd2_handle_cache;
 
-static inline handle_t *jbd_alloc_handle(gfp_t gfp_flags)
+static inline handle_t *jbd2_alloc_handle(gfp_t gfp_flags)
 {
 	return kmem_cache_alloc(jbd2_handle_cache, gfp_flags);
 }
 
-static inline void jbd_free_handle(handle_t *handle)
+static inline void jbd2_free_handle(handle_t *handle)
 {
 	kmem_cache_free(jbd2_handle_cache, handle);
 }
-- 
1.5.3.2.81.g17ed

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