writeback: make congestion functions per bdi_writeback
Currently, all congestion functions take bdi (backing_dev_info) and
always operate on the root wb (bdi->wb) and the congestion state from
the block layer is propagated only for the root blkcg. This patch
introduces {set|clear}_wb_congested() and wb_congested() which take a
bdi_writeback_congested and bdi_writeback respectively. The bdi
counteparts are now wrappers invoking the wb based functions on
@bdi->wb.
While converting clear_bdi_congested() to clear_wb_congested(), the
local variable declaration order between @wqh and @bit is swapped for
cosmetic reason.
This patch just adds the new wb based functions. The following
patches will apply them.
v2: Updated for bdi_writeback_congested.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Jens Axboe <axboe@fb.com>
diff --git a/include/linux/backing-dev.h b/include/linux/backing-dev.h
index 8ae59df..2c498a2 100644
--- a/include/linux/backing-dev.h
+++ b/include/linux/backing-dev.h
@@ -167,27 +167,13 @@
return sb->s_bdi;
}
-static inline int bdi_congested(struct backing_dev_info *bdi, int bdi_bits)
+static inline int wb_congested(struct bdi_writeback *wb, int cong_bits)
{
+ struct backing_dev_info *bdi = wb->bdi;
+
if (bdi->congested_fn)
- return bdi->congested_fn(bdi->congested_data, bdi_bits);
- return (bdi->wb.congested->state & bdi_bits);
-}
-
-static inline int bdi_read_congested(struct backing_dev_info *bdi)
-{
- return bdi_congested(bdi, 1 << WB_sync_congested);
-}
-
-static inline int bdi_write_congested(struct backing_dev_info *bdi)
-{
- return bdi_congested(bdi, 1 << WB_async_congested);
-}
-
-static inline int bdi_rw_congested(struct backing_dev_info *bdi)
-{
- return bdi_congested(bdi, (1 << WB_sync_congested) |
- (1 << WB_async_congested));
+ return bdi->congested_fn(bdi->congested_data, cong_bits);
+ return wb->congested->state & cong_bits;
}
long congestion_wait(int sync, long timeout);
@@ -454,4 +440,25 @@
#endif /* CONFIG_CGROUP_WRITEBACK */
+static inline int bdi_congested(struct backing_dev_info *bdi, int cong_bits)
+{
+ return wb_congested(&bdi->wb, cong_bits);
+}
+
+static inline int bdi_read_congested(struct backing_dev_info *bdi)
+{
+ return bdi_congested(bdi, 1 << WB_sync_congested);
+}
+
+static inline int bdi_write_congested(struct backing_dev_info *bdi)
+{
+ return bdi_congested(bdi, 1 << WB_async_congested);
+}
+
+static inline int bdi_rw_congested(struct backing_dev_info *bdi)
+{
+ return bdi_congested(bdi, (1 << WB_sync_congested) |
+ (1 << WB_async_congested));
+}
+
#endif /* _LINUX_BACKING_DEV_H */