xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

jffs2: get rid of jffs2_sync_super

Browse Source 
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 <artem.bityutskiy@linux.intel.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Artem Bityutskiy
2012-05-07 19:56:53 +03:00
committed by Al Viro
parent 06688905cc
commit 8bdc81c506
4 changed files with 58 additions and 21 deletions
Download Patch File Download Diff File Expand all files Collapse all files

7
fs/jffs2/os-linux.h
View File

@@ -95,6 +95,7 @@ static inline void jffs2_init_inode_info(struct jffs2_inode_info *f)
#define jffs2_ubivol(c) (0)
#define jffs2_ubivol_setup(c) (0)
#define jffs2_ubivol_cleanup(c) do {} while (0)
#define jffs2_dirty_trigger(c) do {} while (0)
#else /* NAND and/or ECC'd NOR support present */
@@ -135,14 +136,10 @@ void jffs2_ubivol_cleanup(struct jffs2_sb_info *c);
#define jffs2_nor_wbuf_flash(c) (c->mtd->type == MTD_NORFLASH && ! (c->mtd->flags & MTD_BIT_WRITEABLE))
int jffs2_nor_wbuf_flash_setup(struct jffs2_sb_info *c);
void jffs2_nor_wbuf_flash_cleanup(struct jffs2_sb_info *c);
void jffs2_dirty_trigger(struct jffs2_sb_info *c);
#endif /* WRITEBUFFER */
static inline void jffs2_dirty_trigger(struct jffs2_sb_info *c)
{
OFNI_BS_2SFFJ(c)->s_dirt = 1;
}
/* background.c */
int jffs2_start_garbage_collect_thread(struct jffs2_sb_info *c);
void jffs2_stop_garbage_collect_thread(struct jffs2_sb_info *c);