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. Signed-off-by: Jens Axboe <[email protected]> --- fs/fs-writeback.c | 40 ++++++++++++++++++++++++++++++---------- include/linux/writeback.h | 2 ++ 2 files changed, 32 insertions(+), 10 deletions(-) diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c index 245c430a2e41..03fda0830bf8 100644 --- a/fs/fs-writeback.c +++ b/fs/fs-writeback.c @@ -1947,6 +1947,34 @@ 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), + false, reason); +} + +void wakeup_flusher_threads_bdi(struct backing_dev_info *bdi, long nr_pages, + enum wb_reason reason) +{ + if (!nr_pages) + nr_pages = get_nr_dirty_pages(); + + rcu_read_lock(); + __wakeup_flusher_threads_bdi(bdi, nr_pages, reason); + rcu_read_unlock(); +} + +/* * Start writeback of `nr_pages' pages. If `nr_pages' is zero, write back * the whole world. */ @@ -1964,16 +1992,8 @@ void wakeup_flusher_threads(long nr_pages, 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), - false, 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 d5815794416c..5a7ed74d1f6f 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(long nr_pages, enum wb_reason reason); +void wakeup_flusher_threads_bdi(struct backing_dev_info *bdi, long nr_pages, + 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
