Hi, Please do checkpatch.pl before sending a patch. Thanks, 2013-09-30 (월), 18:28 +0800, yuan zhong: > Previously, do_checkpoint() will call congestion_wait() for waiting the pages (previous submitted node/meta/data pages) to be written back. > Because congestion_wait() will set a regular period (e.g. HZ / 50 ) for waiting. > For this reason, there is a situation that after the pages have been written back, but the checkpoint thread still wait for congestion_wait to exit. > This is a problem here, especially, when sync a large number of small files or dirs. > In order to avoid this, a wait_list is introduced, the checkpoint thread will be dropped into the wait_list if the pages have not been written back, and will be waked up by contrast. > > Signed-off-by: Yuan Zhong <yuan.mark.zhong@xxxxxxxxxxx> > --- > fs/f2fs/checkpoint.c | 3 +-- > fs/f2fs/f2fs.h | 19 +++++++++++++++++++ > fs/f2fs/segment.c | 1 + > fs/f2fs/super.c | 1 + > 4 files changed, 22 insertions(+), 2 deletions(-) > > diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c index bb31220..cf6b4a5 100644 > --- a/fs/f2fs/checkpoint.c > +++ b/fs/f2fs/checkpoint.c > @@ -756,8 +756,7 @@ static void do_checkpoint(struct f2fs_sb_info *sbi, bool is_umount) > f2fs_put_page(cp_page, 1); > > /* wait for previous submitted node/meta pages writeback */ > - while (get_pages(sbi, F2FS_WRITEBACK)) > - congestion_wait(BLK_RW_ASYNC, HZ / 50); > + f2fs_writeback_wait(sbi); > > filemap_fdatawait_range(sbi->node_inode->i_mapping, 0, LONG_MAX); > filemap_fdatawait_range(sbi->meta_inode->i_mapping, 0, LONG_MAX); diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h index 608f0df..f8b62cc 100644 > --- a/fs/f2fs/f2fs.h > +++ b/fs/f2fs/f2fs.h > @@ -18,6 +18,7 @@ > #include <linux/crc32.h> > #include <linux/magic.h> > #include <linux/kobject.h> > +#include <linux/wait.h> > > /* > * For mount options > @@ -430,6 +431,8 @@ struct f2fs_sb_info { > /* For sysfs suppport */ > struct kobject s_kobj; > struct completion s_kobj_unregister; > + > + wait_queue_head_t writeback_wqh; > }; > > /* > @@ -961,6 +964,22 @@ static inline int f2fs_readonly(struct super_block *sb) > return sb->s_flags & MS_RDONLY; > } > > +static inline void f2fs_writeback_wait(struct f2fs_sb_info *sbi) { > + DEFINE_WAIT(wait); > + > + prepare_to_wait(&sbi->writeback_wqh, &wait, TASK_UNINTERRUPTIBLE); > + if (get_pages(sbi, F2FS_WRITEBACK)) > + io_schedule(); > + finish_wait(&sbi->writeback_wqh, &wait); } > + > +static inline void f2fs_writeback_wake(struct f2fs_sb_info *sbi) { > + if (!get_pages(sbi, F2FS_WRITEBACK)) > + wake_up_all(&sbi->writeback_wqh); > +} > + > /* > * file.c > */ > diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c index 09af9c7..79293fe 100644 > --- a/fs/f2fs/segment.c > +++ b/fs/f2fs/segment.c > @@ -597,6 +597,7 @@ static void f2fs_end_io_write(struct bio *bio, int err) > > if (p->is_sync) > complete(p->wait); > + f2fs_writeback_wake(p->sbi); > kfree(p); > bio_put(bio); > } > diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c index 13d0a0f..b31f686 100644 > --- a/fs/f2fs/super.c > +++ b/fs/f2fs/super.c > @@ -818,6 +818,7 @@ static int f2fs_fill_super(struct super_block *sb, void *data, int silent) > mutex_init(&sbi->gc_mutex); > mutex_init(&sbi->writepages); > mutex_init(&sbi->cp_mutex); > + init_waitqueue_head(&sbi->writeback_wqh); > for (i = 0; i < NR_GLOBAL_LOCKS; i++) > mutex_init(&sbi->fs_lock[i]); > mutex_init(&sbi->node_write); > -- Jaegeuk Kim Samsung -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html