blk-cgroup: remove blkcg_bio_issue_check

blkcg_bio_issue_check is a giant inline function that does three entirely
different things.  Factor out the blk-cgroup related bio initalization
into a new helper, and the open code the sequence in the only caller,
relying on the fact that all the actual functionality is stubbed out for
non-cgroup builds.

Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

1 files changed, 34 insertions, 0 deletions

diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
index d21ec2acd716..1ce94afc03bc 100644
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -1813,6 +1813,40 @@ void bio_clone_blkg_association(struct bio *dst, struct bio *src)
 }
 EXPORT_SYMBOL_GPL(bio_clone_blkg_association);
 
+static int blk_cgroup_io_type(struct bio *bio)
+{
+	if (op_is_discard(bio->bi_opf))
+		return BLKG_IOSTAT_DISCARD;
+	if (op_is_write(bio->bi_opf))
+		return BLKG_IOSTAT_WRITE;
+	return BLKG_IOSTAT_READ;
+}
+
+void blk_cgroup_bio_start(struct bio *bio)
+{
+	int rwd = blk_cgroup_io_type(bio), cpu;
+	struct blkg_iostat_set *bis;
+
+	cpu = get_cpu();
+	bis = per_cpu_ptr(bio->bi_blkg->iostat_cpu, cpu);
+	u64_stats_update_begin(&bis->sync);
+
+	/*
+	 * If the bio is flagged with BIO_CGROUP_ACCT it means this is a split
+	 * bio and we would have already accounted for the size of the bio.
+	 */
+	if (!bio_flagged(bio, BIO_CGROUP_ACCT)) {
+		bio_set_flag(bio, BIO_CGROUP_ACCT);
+			bis->cur.bytes[rwd] += bio->bi_iter.bi_size;
+	}
+	bis->cur.ios[rwd]++;
+
+	u64_stats_update_end(&bis->sync);
+	if (cgroup_subsys_on_dfl(io_cgrp_subsys))
+		cgroup_rstat_updated(bio->bi_blkg->blkcg->css.cgroup, cpu);
+	put_cpu();
+}
+
 static int __init blkcg_init(void)
 {
 	blkcg_punt_bio_wq = alloc_workqueue("blkcg_punt_bio",