From 8bdc81c5069e43755d6e59e5e990e21ca200e8e2 Mon Sep 17 00:00:00 2001 From: Artem Bityutskiy Date: Mon, 7 May 2012 19:56:53 +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: Al Viro --- fs/jffs2/wbuf.c | 55 ++++++++++++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 52 insertions(+), 3 deletions(-) (limited to 'fs/jffs2/wbuf.c') diff --git a/fs/jffs2/wbuf.c b/fs/jffs2/wbuf.c index 74d9be19df3f..6f4529d3697f 100644 --- a/fs/jffs2/wbuf.c +++ b/fs/jffs2/wbuf.c @@ -20,6 +20,7 @@ #include #include #include +#include #include "nodelist.h" @@ -85,7 +86,7 @@ static void jffs2_wbuf_dirties_inode(struct jffs2_sb_info *c, uint32_t ino) { struct jffs2_inodirty *new; - /* Mark the superblock dirty so that kupdated will flush... */ + /* Schedule delayed write-buffer write-out */ jffs2_dirty_trigger(c); if (jffs2_wbuf_pending_for_ino(c, ino)) @@ -1148,6 +1149,47 @@ int jffs2_write_nand_badblock(struct jffs2_sb_info *c, struct jffs2_eraseblock * return 1; } +static struct jffs2_sb_info *work_to_sb(struct work_struct *work) +{ + struct delayed_work *dwork; + + dwork = container_of(work, struct delayed_work, work); + return container_of(dwork, struct jffs2_sb_info, wbuf_dwork); +} + +static void delayed_wbuf_sync(struct work_struct *work) +{ + struct jffs2_sb_info *c = work_to_sb(work); + struct super_block *sb = OFNI_BS_2SFFJ(c); + + spin_lock(&c->wbuf_dwork_lock); + c->wbuf_queued = 0; + spin_unlock(&c->wbuf_dwork_lock); + + if (!(sb->s_flags & MS_RDONLY)) { + jffs2_dbg(1, "%s()\n", __func__); + jffs2_flush_wbuf_gc(c, 0); + } +} + +void jffs2_dirty_trigger(struct jffs2_sb_info *c) +{ + struct super_block *sb = OFNI_BS_2SFFJ(c); + unsigned long delay; + + if (sb->s_flags & MS_RDONLY) + return; + + spin_lock(&c->wbuf_dwork_lock); + if (!c->wbuf_queued) { + jffs2_dbg(1, "%s()\n", __func__); + delay = msecs_to_jiffies(dirty_writeback_interval * 10); + queue_delayed_work(system_long_wq, &c->wbuf_dwork, delay); + c->wbuf_queued = 1; + } + spin_unlock(&c->wbuf_dwork_lock); +} + int jffs2_nand_flash_setup(struct jffs2_sb_info *c) { struct nand_ecclayout *oinfo = c->mtd->ecclayout; @@ -1169,6 +1211,8 @@ int jffs2_nand_flash_setup(struct jffs2_sb_info *c) /* Initialise write buffer */ init_rwsem(&c->wbuf_sem); + spin_lock_init(&c->wbuf_dwork_lock); + INIT_DELAYED_WORK(&c->wbuf_dwork, delayed_wbuf_sync); c->wbuf_pagesize = c->mtd->writesize; c->wbuf_ofs = 0xFFFFFFFF; @@ -1207,8 +1251,8 @@ int jffs2_dataflash_setup(struct jffs2_sb_info *c) { /* Initialize write buffer */ init_rwsem(&c->wbuf_sem); - - + spin_lock_init(&c->wbuf_dwork_lock); + INIT_DELAYED_WORK(&c->wbuf_dwork, delayed_wbuf_sync); c->wbuf_pagesize = c->mtd->erasesize; /* Find a suitable c->sector_size @@ -1267,6 +1311,9 @@ int jffs2_nor_wbuf_flash_setup(struct jffs2_sb_info *c) { /* Initialize write buffer */ init_rwsem(&c->wbuf_sem); + spin_lock_init(&c->wbuf_dwork_lock); + INIT_DELAYED_WORK(&c->wbuf_dwork, delayed_wbuf_sync); + c->wbuf_pagesize = c->mtd->writesize; c->wbuf_ofs = 0xFFFFFFFF; @@ -1299,6 +1346,8 @@ int jffs2_ubivol_setup(struct jffs2_sb_info *c) { return 0; init_rwsem(&c->wbuf_sem); + spin_lock_init(&c->wbuf_dwork_lock); + INIT_DELAYED_WORK(&c->wbuf_dwork, delayed_wbuf_sync); c->wbuf_pagesize = c->mtd->writesize; c->wbuf_ofs = 0xFFFFFFFF; -- cgit