53 struct cgroup_subsys_state * const blkcg_root_css = &blkcg_root.css;
101  * blkcg_css - find the current css
103  * Find the css associated with either the kthread or the current task.
104  * This may return a dying css, so it is up to the caller to use tryget logic
109 	struct cgroup_subsys_state *css;  in blkcg_css()  local
111 	css = kthread_blkcg();  in blkcg_css()
112 	if (css)  in blkcg_css()
113 		return css;  in blkcg_css()
143 	 * Release blkcg css ref only after blkg is removed from q->blkg_list,  in blkg_free_workfn()
146 	css_put(&blkg->blkcg->css);  in blkg_free_workfn()
272  * bio_blkcg_css - return the blkcg CSS associated with a bio
275  * This returns the CSS for the blkcg associated with a bio, or %NULL if not
283 	return &bio->bi_blkg->blkcg->css;  in bio_blkcg_css()
295 	return css_to_blkcg(blkcg->css.parent);  in blkcg_parent()
324 	if (!css_tryget_online(&blkcg->css))  in blkg_alloc()
366 	css_put(&blkcg->css);  in blkg_alloc()
652 static int blkcg_reset_stats(struct cgroup_subsys_state *css,  in blkcg_reset_stats()  argument
655 	struct blkcg *blkcg = css_to_blkcg(css);  in blkcg_reset_stats()
1076 static void blkcg_rstat_flush(struct cgroup_subsys_state *css, int cpu)  in blkcg_rstat_flush()  argument
1079 	if (cgroup_parent(css->cgroup))  in blkcg_rstat_flush()
1080 		__blkcg_rstat_flush(css_to_blkcg(css), cpu);  in blkcg_rstat_flush()
1195 		css_rstat_flush(&blkcg->css);  in blkcg_print_stat()
1221 struct list_head *blkcg_get_cgwb_list(struct cgroup_subsys_state *css)  in blkcg_get_cgwb_list()  argument
1223 	return &css_to_blkcg(css)->cgwb_list;  in blkcg_get_cgwb_list()
1238  *    and handles the destruction of blkgs.  Here the css reference held by
1269  * Destroying the blkgs releases the reference held on the blkcg's css allowing
1336  * @css: css of interest
1338  * This function is called when @css is about to go away.  Here the cgwbs are
1342 static void blkcg_css_offline(struct cgroup_subsys_state *css)  in blkcg_css_offline()  argument
1345 	wb_blkcg_offline(css);  in blkcg_css_offline()
1348 	blkcg_unpin_online(css);  in blkcg_css_offline()
1351 static void blkcg_css_free(struct cgroup_subsys_state *css)  in blkcg_css_free()  argument
1353 	struct blkcg *blkcg = css_to_blkcg(css);  in blkcg_css_free()
1357 	 * Every blkg holds a reference on this css and drops any delay it  in blkcg_css_free()
1431 	return &blkcg->css;  in blkcg_css_alloc()
1446 static int blkcg_css_online(struct cgroup_subsys_state *css)  in blkcg_css_online()  argument
1448 	struct blkcg *parent = blkcg_parent(css_to_blkcg(css));  in blkcg_css_online()
1456 		blkcg_pin_online(&parent->css);  in blkcg_css_online()
2082  * @css: target css
2089 		struct cgroup_subsys_state *css)  in blkg_tryget_closest()  argument
2092 	struct blkcg *blkcg = css_to_blkcg(css);  in blkg_tryget_closest()
2118  * bio_associate_blkg_from_css - associate a bio with a specified css
2120  * @css: target css
2122  * Associate @bio with the blkg found by combining the css's blkg and the
2132 				 struct cgroup_subsys_state *css)  in bio_associate_blkg_from_css()  argument
2137 	if (css && css->parent) {  in bio_associate_blkg_from_css()
2138 		bio->bi_blkg = blkg_tryget_closest(bio, css);  in bio_associate_blkg_from_css()
2150  * Associate @bio with the blkg found from the bio's css and request_queue.
2152  * already associated, the css is reused and association redone as the
2157 	struct cgroup_subsys_state *css;  in bio_associate_blkg()  local
2163 		css = bio_blkcg_css(bio);  in bio_associate_blkg()
2164 		bio_associate_blkg_from_css(bio, css);  in bio_associate_blkg()
2167 		css = blkcg_css();  in bio_associate_blkg()
2168 		if (!css_tryget_online(css))  in bio_associate_blkg()
2169 			css = NULL;  in bio_associate_blkg()
2172 		bio_associate_blkg_from_css(bio, css);  in bio_associate_blkg()
2173 		if (css)  in bio_associate_blkg()
2174 			css_put(css);  in bio_associate_blkg()
2211 	if (!cgroup_parent(blkcg->css.cgroup))  in blk_cgroup_bio_start()
2240 	__css_rstat_updated(&blkcg->css, cpu);  in blk_cgroup_bio_start()