From d8a8559cd7a9ccac98d5f6f13297a2ff68a43627 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Wed, 2 Sep 2009 12:34:32 +0200 Subject: writeback: get rid of generic_sync_sb_inodes() export This adds two new exported functions: - writeback_inodes_sb(), which only attempts to writeback dirty inodes on this super_block, for WB_SYNC_NONE writeout. - sync_inodes_sb(), which writes out all dirty inodes on this super_block and also waits for the IO to complete. Acked-by: Jan Kara Signed-off-by: Jens Axboe --- fs/fs-writeback.c | 70 +++++++++++++++++++++++++++++++++---------------------- fs/sync.c | 18 +++++++------- fs/ubifs/budget.c | 16 ++----------- fs/ubifs/super.c | 8 +------ 4 files changed, 55 insertions(+), 57 deletions(-) (limited to 'fs') diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c index c54226be529..271e5f44e87 100644 --- a/fs/fs-writeback.c +++ b/fs/fs-writeback.c @@ -458,8 +458,8 @@ writeback_single_inode(struct inode *inode, struct writeback_control *wbc) * on the writer throttling path, and we get decent balancing between many * throttled threads: we don't want them all piling up on inode_sync_wait. */ -void generic_sync_sb_inodes(struct super_block *sb, - struct writeback_control *wbc) +static void generic_sync_sb_inodes(struct super_block *sb, + struct writeback_control *wbc) { const unsigned long start = jiffies; /* livelock avoidance */ int sync = wbc->sync_mode == WB_SYNC_ALL; @@ -593,13 +593,6 @@ void generic_sync_sb_inodes(struct super_block *sb, return; /* Leave any unwritten inodes on s_io */ } -EXPORT_SYMBOL_GPL(generic_sync_sb_inodes); - -static void sync_sb_inodes(struct super_block *sb, - struct writeback_control *wbc) -{ - generic_sync_sb_inodes(sb, wbc); -} /* * Start writeback of dirty pagecache data against all unlocked inodes. @@ -640,7 +633,7 @@ restart: */ if (down_read_trylock(&sb->s_umount)) { if (sb->s_root) - sync_sb_inodes(sb, wbc); + generic_sync_sb_inodes(sb, wbc); up_read(&sb->s_umount); } spin_lock(&sb_lock); @@ -653,35 +646,56 @@ restart: spin_unlock(&sb_lock); } -/* - * writeback and wait upon the filesystem's dirty inodes. The caller will - * do this in two passes - one to write, and one to wait. - * - * A finite limit is set on the number of pages which will be written. - * To prevent infinite livelock of sys_sync(). +/** + * writeback_inodes_sb - writeback dirty inodes from given super_block + * @sb: the superblock * - * We add in the number of potentially dirty inodes, because each inode write - * can dirty pagecache in the underlying blockdev. + * Start writeback on some inodes on this super_block. No guarantees are made + * on how many (if any) will be written, and this function does not wait + * for IO completion of submitted IO. The number of pages submitted is + * returned. */ -void sync_inodes_sb(struct super_block *sb, int wait) +long writeback_inodes_sb(struct super_block *sb) { struct writeback_control wbc = { - .sync_mode = wait ? WB_SYNC_ALL : WB_SYNC_NONE, + .sync_mode = WB_SYNC_NONE, .range_start = 0, .range_end = LLONG_MAX, }; + unsigned long nr_dirty = global_page_state(NR_FILE_DIRTY); + unsigned long nr_unstable = global_page_state(NR_UNSTABLE_NFS); + long nr_to_write; - if (!wait) { - unsigned long nr_dirty = global_page_state(NR_FILE_DIRTY); - unsigned long nr_unstable = global_page_state(NR_UNSTABLE_NFS); - - wbc.nr_to_write = nr_dirty + nr_unstable + + nr_to_write = nr_dirty + nr_unstable + (inodes_stat.nr_inodes - inodes_stat.nr_unused); - } else - wbc.nr_to_write = LONG_MAX; /* doesn't actually matter */ - sync_sb_inodes(sb, &wbc); + wbc.nr_to_write = nr_to_write; + generic_sync_sb_inodes(sb, &wbc); + return nr_to_write - wbc.nr_to_write; +} +EXPORT_SYMBOL(writeback_inodes_sb); + +/** + * sync_inodes_sb - sync sb inode pages + * @sb: the superblock + * + * This function writes and waits on any dirty inode belonging to this + * super_block. The number of pages synced is returned. + */ +long sync_inodes_sb(struct super_block *sb) +{ + struct writeback_control wbc = { + .sync_mode = WB_SYNC_ALL, + .range_start = 0, + .range_end = LLONG_MAX, + }; + long nr_to_write = LONG_MAX; /* doesn't actually matter */ + + wbc.nr_to_write = nr_to_write; + generic_sync_sb_inodes(sb, &wbc); + return nr_to_write - wbc.nr_to_write; } +EXPORT_SYMBOL(sync_inodes_sb); /** * write_inode_now - write an inode to disk diff --git a/fs/sync.c b/fs/sync.c index 3422ba61d86..66f210476f4 100644 --- a/fs/sync.c +++ b/fs/sync.c @@ -19,20 +19,22 @@ SYNC_FILE_RANGE_WAIT_AFTER) /* - * Do the filesystem syncing work. For simple filesystems sync_inodes_sb(sb, 0) - * just dirties buffers with inodes so we have to submit IO for these buffers - * via __sync_blockdev(). This also speeds up the wait == 1 case since in that - * case write_inode() functions do sync_dirty_buffer() and thus effectively - * write one block at a time. + * Do the filesystem syncing work. For simple filesystems + * writeback_inodes_sb(sb) just dirties buffers with inodes so we have to + * submit IO for these buffers via __sync_blockdev(). This also speeds up the + * wait == 1 case since in that case write_inode() functions do + * sync_dirty_buffer() and thus effectively write one block at a time. */ static int __sync_filesystem(struct super_block *sb, int wait) { /* Avoid doing twice syncing and cache pruning for quota sync */ - if (!wait) + if (!wait) { writeout_quota_sb(sb, -1); - else + writeback_inodes_sb(sb); + } else { sync_quota_sb(sb, -1); - sync_inodes_sb(sb, wait); + sync_inodes_sb(sb); + } if (sb->s_op->sync_fs) sb->s_op->sync_fs(sb, wait); return __sync_blockdev(sb->s_bdev, wait); diff --git a/fs/ubifs/budget.c b/fs/ubifs/budget.c index eaf6d891d46..1c8991b0db1 100644 --- a/fs/ubifs/budget.c +++ b/fs/ubifs/budget.c @@ -65,26 +65,14 @@ static int shrink_liability(struct ubifs_info *c, int nr_to_write) { int nr_written; - struct writeback_control wbc = { - .sync_mode = WB_SYNC_NONE, - .range_end = LLONG_MAX, - .nr_to_write = nr_to_write, - }; - - generic_sync_sb_inodes(c->vfs_sb, &wbc); - nr_written = nr_to_write - wbc.nr_to_write; + nr_written = writeback_inodes_sb(c->vfs_sb); if (!nr_written) { /* * Re-try again but wait on pages/inodes which are being * written-back concurrently (e.g., by pdflush). */ - memset(&wbc, 0, sizeof(struct writeback_control)); - wbc.sync_mode = WB_SYNC_ALL; - wbc.range_end = LLONG_MAX; - wbc.nr_to_write = nr_to_write; - generic_sync_sb_inodes(c->vfs_sb, &wbc); - nr_written = nr_to_write - wbc.nr_to_write; + nr_written = sync_inodes_sb(c->vfs_sb); } dbg_budg("%d pages were written back", nr_written); diff --git a/fs/ubifs/super.c b/fs/ubifs/super.c index 26d2e0d8046..8d6050a5966 100644 --- a/fs/ubifs/super.c +++ b/fs/ubifs/super.c @@ -438,12 +438,6 @@ static int ubifs_sync_fs(struct super_block *sb, int wait) { int i, err; struct ubifs_info *c = sb->s_fs_info; - struct writeback_control wbc = { - .sync_mode = WB_SYNC_ALL, - .range_start = 0, - .range_end = LLONG_MAX, - .nr_to_write = LONG_MAX, - }; /* * Zero @wait is just an advisory thing to help the file system shove @@ -462,7 +456,7 @@ static int ubifs_sync_fs(struct super_block *sb, int wait) * the user be able to get more accurate results of 'statfs()' after * they synchronize the file system. */ - generic_sync_sb_inodes(sb, &wbc); + sync_inodes_sb(sb); /* * Synchronize write buffers, because 'ubifs_run_commit()' does not -- cgit v1.2.3