From e8dfc30582995ae12454cda517b17d6294175b07 Mon Sep 17 00:00:00 2001 From: Wu Fengguang Date: Thu, 21 Apr 2011 12:06:32 -0600 Subject: [PATCH] writeback: elevate queue_io() into wb_writeback() Code refactor for more logical code layout. No behavior change. - remove the mis-named __writeback_inodes_sb() - wb_writeback()/writeback_inodes_wb() will decide when to queue_io() before calling __writeback_inodes_wb() Acked-by: Jan Kara Signed-off-by: Wu Fengguang --- fs/fs-writeback.c | 29 ++++++++++++----------------- 1 file changed, 12 insertions(+), 17 deletions(-) diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c index 36a30917e0dc..565b1fd15be6 100644 --- a/fs/fs-writeback.c +++ b/fs/fs-writeback.c @@ -580,17 +580,13 @@ static int writeback_sb_inodes(struct super_block *sb, struct bdi_writeback *wb, return 1; } -void writeback_inodes_wb(struct bdi_writeback *wb, - struct writeback_control *wbc) +static void __writeback_inodes_wb(struct bdi_writeback *wb, + struct writeback_control *wbc) { int ret = 0; if (!wbc->wb_start) wbc->wb_start = jiffies; /* livelock avoidance */ - spin_lock(&wb->list_lock); - - if (list_empty(&wb->b_io)) - queue_io(wb, wbc->older_than_this); while (!list_empty(&wb->b_io)) { struct inode *inode = wb_inode(wb->b_io.prev); @@ -606,19 +602,16 @@ void writeback_inodes_wb(struct bdi_writeback *wb, if (ret) break; } - spin_unlock(&wb->list_lock); /* Leave any unwritten inodes on b_io */ } -static void __writeback_inodes_sb(struct super_block *sb, - struct bdi_writeback *wb, struct writeback_control *wbc) +void writeback_inodes_wb(struct bdi_writeback *wb, + struct writeback_control *wbc) { - WARN_ON(!rwsem_is_locked(&sb->s_umount)); - spin_lock(&wb->list_lock); if (list_empty(&wb->b_io)) queue_io(wb, wbc->older_than_this); - writeback_sb_inodes(sb, wb, wbc, true); + __writeback_inodes_wb(wb, wbc); spin_unlock(&wb->list_lock); } @@ -685,7 +678,7 @@ static long wb_writeback(struct bdi_writeback *wb, * The intended call sequence for WB_SYNC_ALL writeback is: * * wb_writeback() - * __writeback_inodes_sb() <== called only once + * writeback_sb_inodes() <== called only once * write_cache_pages() <== called once for each inode * (quickly) tag currently dirty pages * (maybe slowly) sync all tagged pages @@ -694,6 +687,7 @@ static long wb_writeback(struct bdi_writeback *wb, write_chunk = LONG_MAX; wbc.wb_start = jiffies; /* livelock avoidance */ + spin_lock(&wb->list_lock); for (;;) { /* * Stop writeback when nr_pages has been consumed @@ -730,10 +724,12 @@ static long wb_writeback(struct bdi_writeback *wb, wbc.inodes_written = 0; trace_wbc_writeback_start(&wbc, wb->bdi); + if (list_empty(&wb->b_io)) + queue_io(wb, wbc.older_than_this); if (work->sb) - __writeback_inodes_sb(work->sb, wb, &wbc); + writeback_sb_inodes(work->sb, wb, &wbc, true); else - writeback_inodes_wb(wb, &wbc); + __writeback_inodes_wb(wb, &wbc); trace_wbc_writeback_written(&wbc, wb->bdi); work->nr_pages -= write_chunk - wbc.nr_to_write; @@ -761,7 +757,6 @@ static long wb_writeback(struct bdi_writeback *wb, * become available for writeback. Otherwise * we'll just busyloop. */ - spin_lock(&wb->list_lock); if (!list_empty(&wb->b_more_io)) { inode = wb_inode(wb->b_more_io.prev); trace_wbc_writeback_wait(&wbc, wb->bdi); @@ -769,8 +764,8 @@ static long wb_writeback(struct bdi_writeback *wb, inode_wait_for_writeback(inode, wb); spin_unlock(&inode->i_lock); } - spin_unlock(&wb->list_lock); } + spin_unlock(&wb->list_lock); return wrote; }