From 208b14e507c00ff7f108e1a388dd3d8cc805a443 Mon Sep 17 00:00:00 2001 From: Artem Bityutskiy Date: Mon, 7 May 2012 19:02:46 +0300 Subject: jffs2: get rid of jffs2_sync_super Currently JFFS2 file-system maps the VFS "superblock" abstraction to the write-buffer. Namely, it uses VFS services to synchronize the write-buffer periodically. The whole "superblock write-out" VFS infrastructure is served by the 'sync_supers()' kernel thread, which wakes up every 5 (by default) seconds and writes out all dirty superblock using the '->write_super()' call-back. But the problem with this thread is that it wastes power by waking up the system every 5 seconds no matter what. So we want to kill it completely and thus, we need to make file-systems to stop using the '->write_super' VFS service, and then remove it together with the kernel thread. This patch switches the JFFS2 write-buffer management from '->write_super()'/'->s_dirt' to a delayed work. Instead of setting the 's_dirt' flag we just schedule a delayed work for synchronizing the write-buffer. Signed-off-by: Artem Bityutskiy Signed-off-by: David Woodhouse --- fs/jffs2/jffs2_fs_sb.h | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'fs/jffs2/jffs2_fs_sb.h') diff --git a/fs/jffs2/jffs2_fs_sb.h b/fs/jffs2/jffs2_fs_sb.h index 0d00bf26923b..413ef89c2d1b 100644 --- a/fs/jffs2/jffs2_fs_sb.h +++ b/fs/jffs2/jffs2_fs_sb.h @@ -133,6 +133,10 @@ struct jffs2_sb_info { struct jffs2_inodirty *wbuf_inodes; struct rw_semaphore wbuf_sem; /* Protects the write buffer */ + struct delayed_work wbuf_dwork; /* write-buffer write-out work */ + int wbuf_queued; /* non-zero delayed work is queued */ + spinlock_t wbuf_dwork_lock; /* protects wbuf_dwork and and wbuf_queued */ + unsigned char *oobbuf; int oobavail; /* How many bytes are available for JFFS2 in OOB */ #endif -- cgit v1.2.3-55-g7522