buffer, writeback: make __block_write_full_page() honor cgroup writeback
[__]block_write_full_page() is used to implement ->writepage in
various filesystems. All writeback logic is now updated to handle
cgroup writeback and the block cgroup to issue IOs for is encoded in
writeback_control and can be retrieved using wbc_blkcg_css(); however,
[__]block_write_full_page() currently ignores the blkcg indicated by
wbc and issues all bio's without explicit blkcg association.
This patch adds submit_bh_blkcg() which associates the bio with the
specified blkio cgroup before issuing and uses it in
__block_write_full_page() so that the issued bio's are associated with
wbc_blkcg_css().
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jan Kara <jack@suse.cz>
Cc: Andrew Morton <akpm@linux-foundation.org>
diff --git a/fs/buffer.c b/fs/buffer.c
index 2dab7dd..1377346 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -45,6 +45,9 @@
#include <trace/events/block.h>
static int fsync_buffers_list(spinlock_t *lock, struct list_head *list);
+static int submit_bh_blkcg(int rw, struct buffer_head *bh,
+ unsigned long bio_flags,
+ struct cgroup_subsys_state *blkcg_css);
#define BH_ENTRY(list) list_entry((list), struct buffer_head, b_assoc_buffers)
@@ -1777,7 +1780,7 @@
do {
struct buffer_head *next = bh->b_this_page;
if (buffer_async_write(bh)) {
- submit_bh(write_op, bh);
+ submit_bh_blkcg(write_op, bh, 0, wbc_blkcg_css(wbc));
nr_underway++;
}
bh = next;
@@ -1831,7 +1834,7 @@
struct buffer_head *next = bh->b_this_page;
if (buffer_async_write(bh)) {
clear_buffer_dirty(bh);
- submit_bh(write_op, bh);
+ submit_bh_blkcg(write_op, bh, 0, wbc_blkcg_css(wbc));
nr_underway++;
}
bh = next;
@@ -3000,7 +3003,9 @@
}
}
-int _submit_bh(int rw, struct buffer_head *bh, unsigned long bio_flags)
+static int submit_bh_blkcg(int rw, struct buffer_head *bh,
+ unsigned long bio_flags,
+ struct cgroup_subsys_state *blkcg_css)
{
struct bio *bio;
int ret = 0;
@@ -3023,6 +3028,9 @@
*/
bio = bio_alloc(GFP_NOIO, 1);
+ if (blkcg_css)
+ bio_associate_blkcg(bio, blkcg_css);
+
bio->bi_iter.bi_sector = bh->b_blocknr * (bh->b_size >> 9);
bio->bi_bdev = bh->b_bdev;
bio->bi_io_vec[0].bv_page = bh->b_page;
@@ -3053,11 +3061,16 @@
bio_put(bio);
return ret;
}
+
+int _submit_bh(int rw, struct buffer_head *bh, unsigned long bio_flags)
+{
+ return submit_bh_blkcg(rw, bh, bio_flags, NULL);
+}
EXPORT_SYMBOL_GPL(_submit_bh);
int submit_bh(int rw, struct buffer_head *bh)
{
- return _submit_bh(rw, bh, 0);
+ return submit_bh_blkcg(rw, bh, 0, NULL);
}
EXPORT_SYMBOL(submit_bh);
