diff options
| author |   Tejun Heo <tj@kernel.org> | 2015-05-22 17:13:46 -0400 |
|---|---|---|
| committer |   Jens Axboe <axboe@fb.com> | 2015-06-02 08:33:35 -0600 |
| commit | 766a9d6e60578f1ef6de71f89f022084f8bffc82 (patch) | |
| tree | c14261a70cdc790ffca5e82fa006fa8adf663319 | |
| parent | writeback: implement WB_has_dirty_io wb_state flag (diff) | |
| download | linux-dev-766a9d6e60578f1ef6de71f89f022084f8bffc82.tar.xz linux-dev-766a9d6e60578f1ef6de71f89f022084f8bffc82.zip | |
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 <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
| -rw-r--r-- | fs/fs-writeback.c | 7 | ||||
| -rw-r--r-- | include/linux/backing-dev-defs.h | 2 | ||||
| -rw-r--r-- | mm/page-writeback.c | 3 |
3 files changed, 11 insertions, 1 deletions
diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c index 0a90dc557748..bbccf68b38db 100644 --- a/fs/fs-writeback.c +++ b/fs/fs-writeback.c @@ -99,6 +99,8 @@ static bool wb_io_lists_populated(struct bdi_writeback *wb) return false; } else { set_bit(WB_has_dirty_io, &wb->state); + atomic_long_add(wb->avg_write_bandwidth, + &wb->bdi->tot_write_bandwidth); return true; } } @@ -106,8 +108,11 @@ static bool wb_io_lists_populated(struct bdi_writeback *wb) static void wb_io_lists_depopulated(struct bdi_writeback *wb) { if (wb_has_dirty_io(wb) && list_empty(&wb->b_dirty) && - list_empty(&wb->b_io) && list_empty(&wb->b_more_io)) + list_empty(&wb->b_io) && list_empty(&wb->b_more_io)) { clear_bit(WB_has_dirty_io, &wb->state); + atomic_long_sub(wb->avg_write_bandwidth, + &wb->bdi->tot_write_bandwidth); + } } /** diff --git a/include/linux/backing-dev-defs.h b/include/linux/backing-dev-defs.h index 7a94b7850b7c..d631a61f4023 100644 --- a/include/linux/backing-dev-defs.h +++ b/include/linux/backing-dev-defs.h @@ -142,6 +142,8 @@ struct backing_dev_info { unsigned int min_ratio; unsigned int max_ratio, max_prop_frac; + atomic_long_t tot_write_bandwidth; /* sum of active avg_write_bw */ + struct bdi_writeback wb; /* the root writeback info for this bdi */ struct bdi_writeback_congested wb_congested; /* its congested state */ #ifdef CONFIG_CGROUP_WRITEBACK 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; } |