From 766a9d6e60578f1ef6de71f89f022084f8bffc82 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Fri, 22 May 2015 17:13:46 -0400 Subject: writeback: implement backing_dev_info->tot_write_bandwidth cgroup writeback support needs to keep track of the sum of avg_write_bandwidth of all wb's (bdi_writeback's) with dirty inodes to distribute write workload. This patch adds bdi->tot_write_bandwidth and updates inode_wb_list_move_locked(), inode_wb_list_del_locked() and wb_update_write_bandwidth() to adjust it as wb's gain and lose dirty inodes and its avg_write_bandwidth gets updated. As the update events are not synchronized with each other, bdi->tot_write_bandwidth is an atomic_long_t. Signed-off-by: Tejun Heo Cc: Jens Axboe Cc: Jan Kara Signed-off-by: Jens Axboe --- mm/page-writeback.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'mm/page-writeback.c') diff --git a/mm/page-writeback.c b/mm/page-writeback.c index e31dea94d116..c95eb24dd652 100644 --- a/mm/page-writeback.c +++ b/mm/page-writeback.c @@ -881,6 +881,9 @@ static void wb_update_write_bandwidth(struct bdi_writeback *wb, avg += (old - avg) >> 3; out: + if (wb_has_dirty_io(wb)) + atomic_long_add(avg - wb->avg_write_bandwidth, + &wb->bdi->tot_write_bandwidth); wb->write_bandwidth = bw; wb->avg_write_bandwidth = avg; } -- cgit v1.2.3