Similar to wakeup_flusher_threads(), except that we only wake
up the flusher threads on the specified backing device.
No functional changes in this patch.
Acked-by: Johannes Weiner <hannes@xxxxxxxxxxx>
Tested-by: Chris Mason <clm@xxxxxx>
Reviewed-by: Jan Kara <jack@xxxxxxx>
Reviewed-by: Christoph Hellwig <hch@xxxxxx>
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
---
fs/fs-writeback.c | 39 +++++++++++++++++++++++++++++----------
include/linux/writeback.h | 2 ++
2 files changed, 31 insertions(+), 10 deletions(-)
diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index 65e6992d8719..1a9b45250437 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -1947,6 +1947,33 @@ void wb_workfn(struct work_struct *work)
}
/*
+ * Start writeback of `nr_pages' pages on this bdi. If `nr_pages' is zero,
+ * write back the whole world.
+ */
+static void __wakeup_flusher_threads_bdi(struct backing_dev_info *bdi,
+ long nr_pages, enum wb_reason reason)
+{
+ struct bdi_writeback *wb;
+
+ if (!bdi_has_dirty_io(bdi))
+ return;
+
+ list_for_each_entry_rcu(wb, &bdi->wb_list, bdi_node)
+ wb_start_writeback(wb, wb_split_bdi_pages(wb, nr_pages),
+ true, reason);
+}
+
+void wakeup_flusher_threads_bdi(struct backing_dev_info *bdi,
+ enum wb_reason reason)
+{
+ long nr_pages = get_nr_dirty_pages();
+
+ rcu_read_lock();
+ __wakeup_flusher_threads_bdi(bdi, nr_pages, reason);
+ rcu_read_unlock();
+}
+
+/*
* Wakeup the flusher threads to start writeback of all currently dirty pages
*/
void wakeup_flusher_threads(enum wb_reason reason)
@@ -1963,16 +1990,8 @@ void wakeup_flusher_threads(enum wb_reason reason)
nr_pages = get_nr_dirty_pages();
rcu_read_lock();
- list_for_each_entry_rcu(bdi, &bdi_list, bdi_list) {
- struct bdi_writeback *wb;
-
- if (!bdi_has_dirty_io(bdi))
- continue;
-
- list_for_each_entry_rcu(wb, &bdi->wb_list, bdi_node)
- wb_start_writeback(wb, wb_split_bdi_pages(wb, nr_pages),
- true, reason);
- }
+ list_for_each_entry_rcu(bdi, &bdi_list, bdi_list)
+ __wakeup_flusher_threads_bdi(bdi, nr_pages, reason);
rcu_read_unlock();
}
diff --git a/include/linux/writeback.h b/include/linux/writeback.h
index 1f9c6db5e29a..9c0091678af4 100644
--- a/include/linux/writeback.h
+++ b/include/linux/writeback.h
@@ -190,6 +190,8 @@ bool try_to_writeback_inodes_sb_nr(struct super_block *, unsigned long nr,
enum wb_reason reason);
void sync_inodes_sb(struct super_block *);
void wakeup_flusher_threads(enum wb_reason reason);
+void wakeup_flusher_threads_bdi(struct backing_dev_info *bdi,
+ enum wb_reason reason);
void inode_wait_for_writeback(struct inode *inode);
/* writeback.h requires fs.h; it, too, is not included from here. */
--
2.7.4
