From: Theodore Ts'o Subject: [PATCH 6/6] ext4: Dynamically allocate the jbd2_inode in ext4_inode_info as necessary Date: Tue, 4 Jan 2011 20:01:10 -0500 Message-ID: <1294189270-16733-7-git-send-email-tytso@mit.edu> References: <1294189270-16733-1-git-send-email-tytso@mit.edu> Cc: Theodore Ts'o To: Ext4 Developers List Return-path: Received: from thunk.org ([69.25.196.29]:56650 "EHLO thunker.thunk.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751241Ab1AEBBS (ORCPT ); Tue, 4 Jan 2011 20:01:18 -0500 In-Reply-To: <1294189270-16733-1-git-send-email-tytso@mit.edu> Sender: linux-ext4-owner@vger.kernel.org List-ID: Replace the jbd2_inode structure (which is 48 bytes) with a pointer and only allocate the jbd2_inode when it is needed --- that is, when the file system has a journal present and the inode has been opened for writing. This allows us to further slim down the ext4_inode_info structure. Signed-off-by: "Theodore Ts'o" --- fs/ext4/ext4.h | 2 +- fs/ext4/ext4_jbd2.h | 2 +- fs/ext4/file.c | 19 +++++++++++++++++++ fs/ext4/inode.c | 15 +++++++++++---- fs/ext4/super.c | 16 +++++++--------- fs/jbd2/journal.c | 20 +++++++++++++------- include/linux/jbd2.h | 20 ++++++++++++++++++-- 7 files changed, 70 insertions(+), 24 deletions(-) diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index 8a2603d..50f35e8 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -811,7 +811,7 @@ struct ext4_inode_info { */ struct rw_semaphore i_data_sem; struct inode vfs_inode; - struct jbd2_inode jinode; + struct jbd2_inode *jinode; struct ext4_ext_cache i_cached_extent; /* diff --git a/fs/ext4/ext4_jbd2.h b/fs/ext4/ext4_jbd2.h index b0bd792..d8b992e 100644 --- a/fs/ext4/ext4_jbd2.h +++ b/fs/ext4/ext4_jbd2.h @@ -253,7 +253,7 @@ static inline int ext4_journal_force_commit(journal_t *journal) static inline int ext4_jbd2_file_inode(handle_t *handle, struct inode *inode) { if (ext4_handle_valid(handle)) - return jbd2_journal_file_inode(handle, &EXT4_I(inode)->jinode); + return jbd2_journal_file_inode(handle, EXT4_I(inode)->jinode); return 0; } diff --git a/fs/ext4/file.c b/fs/ext4/file.c index 5a5c55d..45a656f 100644 --- a/fs/ext4/file.c +++ b/fs/ext4/file.c @@ -104,6 +104,7 @@ static int ext4_file_open(struct inode * inode, struct file * filp) { struct super_block *sb = inode->i_sb; struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); + struct ext4_inode_info *ei = EXT4_I(inode); struct vfsmount *mnt = filp->f_path.mnt; struct path path; char buf[64], *cp; @@ -127,6 +128,24 @@ static int ext4_file_open(struct inode * inode, struct file * filp) ext4_mark_super_dirty(sb); } } + /* + * Set up the jbd2_inode if we are opening the inode for + * writing and the journal is present + */ + if (sbi->s_journal && !ei->jinode && (filp->f_mode & FMODE_WRITE)) { + struct jbd2_inode *jinode = jbd2_alloc_inode(GFP_KERNEL); + + spin_lock(&inode->i_lock); + if (!ei->jinode) { + if (!jinode) { + spin_unlock(&inode->i_lock); + return -ENOMEM; + } + ei->jinode = jinode; + jbd2_journal_init_jbd_inode(ei->jinode, inode); + } + spin_unlock(&inode->i_lock); + } return dquot_file_open(inode, filp); } diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index 2d60028..de3f2e3 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -55,10 +55,17 @@ static inline int ext4_begin_ordered_truncate(struct inode *inode, loff_t new_size) { trace_ext4_begin_ordered_truncate(inode, new_size); - return jbd2_journal_begin_ordered_truncate( - EXT4_SB(inode->i_sb)->s_journal, - &EXT4_I(inode)->jinode, - new_size); + /* + * If jinode is zero, then we never opened the file for + * writing, so there's no need to call + * jbd2_journal_begin_ordered_truncate() since there's no + * outstanding writes we need to flush. + */ + if (!EXT4_I(inode)->jinode) + return 0; + return jbd2_journal_begin_ordered_truncate(EXT4_JOURNAL(inode), + EXT4_I(inode)->jinode, + new_size); } static void ext4_invalidatepage(struct page *page, unsigned long offset); diff --git a/fs/ext4/super.c b/fs/ext4/super.c index f5960d6..7f99ac7 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -818,12 +818,6 @@ static struct inode *ext4_alloc_inode(struct super_block *sb) memset(&ei->i_cached_extent, 0, sizeof(struct ext4_ext_cache)); INIT_LIST_HEAD(&ei->i_prealloc_list); spin_lock_init(&ei->i_prealloc_lock); - /* - * Note: We can be called before EXT4_SB(sb)->s_journal is set, - * therefore it can be null here. Don't check it, just initialize - * jinode. - */ - jbd2_journal_init_jbd_inode(&ei->jinode, &ei->vfs_inode); ei->i_reserved_data_blocks = 0; ei->i_reserved_meta_blocks = 0; ei->i_allocated_meta_blocks = 0; @@ -832,6 +826,7 @@ static struct inode *ext4_alloc_inode(struct super_block *sb) #ifdef CONFIG_QUOTA ei->i_reserved_quota = 0; #endif + ei->jinode = 0; INIT_LIST_HEAD(&ei->i_completed_io_list); spin_lock_init(&ei->i_completed_io_lock); ei->cur_aio_dio = NULL; @@ -900,9 +895,12 @@ void ext4_clear_inode(struct inode *inode) end_writeback(inode); dquot_drop(inode); ext4_discard_preallocations(inode); - if (EXT4_JOURNAL(inode)) - jbd2_journal_release_jbd_inode(EXT4_SB(inode->i_sb)->s_journal, - &EXT4_I(inode)->jinode); + if (EXT4_JOURNAL(inode) && EXT4_I(inode)->jinode) { + jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode), + EXT4_I(inode)->jinode); + jbd2_free_inode(EXT4_I(inode)->jinode); + EXT4_I(inode)->jinode = 0; + } } static inline void ext4_show_quota_options(struct seq_file *seq, diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c index 2447bd8..9e46869 100644 --- a/fs/jbd2/journal.c +++ b/fs/jbd2/journal.c @@ -94,6 +94,7 @@ EXPORT_SYMBOL(jbd2_journal_file_inode); EXPORT_SYMBOL(jbd2_journal_init_jbd_inode); EXPORT_SYMBOL(jbd2_journal_release_jbd_inode); EXPORT_SYMBOL(jbd2_journal_begin_ordered_truncate); +EXPORT_SYMBOL(jbd2_inode_cache); static int journal_convert_superblock_v1(journal_t *, journal_superblock_t *); static void __journal_abort_soft (journal_t *journal, int errno); @@ -2286,17 +2287,19 @@ static void __exit jbd2_remove_jbd_stats_proc_entry(void) #endif -struct kmem_cache *jbd2_handle_cache; +struct kmem_cache *jbd2_handle_cache, *jbd2_inode_cache; static int __init journal_init_handle_cache(void) { - jbd2_handle_cache = kmem_cache_create("jbd2_journal_handle", - sizeof(handle_t), - 0, /* offset */ - SLAB_TEMPORARY, /* flags */ - NULL); /* ctor */ + jbd2_handle_cache = KMEM_CACHE(jbd2_journal_handle, SLAB_TEMPORARY); if (jbd2_handle_cache == NULL) { - printk(KERN_EMERG "JBD: failed to create handle cache\n"); + printk(KERN_EMERG "JBD2: failed to create handle cache\n"); + return -ENOMEM; + } + jbd2_inode_cache = KMEM_CACHE(jbd2_inode, 0); + if (jbd2_inode_cache == NULL) { + printk(KERN_EMERG "JBD2: failed to create inode cache\n"); + kmem_cache_destroy(jbd2_handle_cache); return -ENOMEM; } return 0; @@ -2306,6 +2309,9 @@ static void jbd2_journal_destroy_handle_cache(void) { if (jbd2_handle_cache) kmem_cache_destroy(jbd2_handle_cache); + if (jbd2_inode_cache) + kmem_cache_destroy(jbd2_inode_cache); + } /* diff --git a/include/linux/jbd2.h b/include/linux/jbd2.h index 2ae86aa..27e79c2 100644 --- a/include/linux/jbd2.h +++ b/include/linux/jbd2.h @@ -94,7 +94,7 @@ extern void jbd2_free(void *ptr, size_t size); * * This is an opaque datatype. **/ -typedef struct handle_s handle_t; /* Atomic operation type */ +typedef struct jbd2_journal_handle handle_t; /* Atomic operation type */ /** @@ -416,7 +416,7 @@ struct jbd2_revoke_table_s; * in so it can be fixed later. */ -struct handle_s +struct jbd2_journal_handle { /* Which compound transaction is this update a part of? */ transaction_t *h_transaction; @@ -1158,6 +1158,22 @@ static inline void jbd2_free_handle(handle_t *handle) kmem_cache_free(jbd2_handle_cache, handle); } +/* + * jbd2_inode management (optional, for those file systems that want to use + * dynamically allocated jbd2_inode structures) + */ +extern struct kmem_cache *jbd2_inode_cache; + +static inline struct jbd2_inode *jbd2_alloc_inode(gfp_t gfp_flags) +{ + return kmem_cache_alloc(jbd2_inode_cache, gfp_flags); +} + +static inline void jbd2_free_inode(struct jbd2_inode *jinode) +{ + kmem_cache_free(jbd2_inode_cache, jinode); +} + /* Primary revoke support */ #define JOURNAL_REVOKE_DEFAULT_HASH 256 extern int jbd2_journal_init_revoke(journal_t *, int); -- 1.7.3.1