blkcg, writeback: Implement wbc_blkcg_css() (653c45c6) · Commits · 戴 / test

Add a helper to determine the target blkcg from wbc. Reviewed-by:

include/linux/writeback.h

+11 −0

Original line number	Diff line number	Diff line
		@@ -11,6 +11,7 @@
		#include <linux/flex_proportions.h>
		#include <linux/backing-dev-defs.h>
		#include <linux/blk_types.h>
		#include <linux/blk-cgroup.h>

		struct bio;

		@@ -101,6 +102,16 @@ static inline int wbc_to_write_flags(struct writeback_control *wbc)
		return 0;
		}

		static inline struct cgroup_subsys_state *
		wbc_blkcg_css(struct writeback_control *wbc)
		{
		#ifdef CONFIG_CGROUP_WRITEBACK
		if (wbc->wb)
		return wbc->wb->blkcg_css;
		#endif
		return blkcg_root_css;
		}

		/*
		* A wb_domain represents a domain that wb's (bdi_writeback's) belong to
		* and are measured against each other in. There always is one global