linux/include/linux/blk-cgroup.h
/**
 * blkcg_cgwb_put - put a reference for @blkcg->cgwb_list
 * @blkcg: blkcg of interest
 *
 * This is used to track the number of active wb's related to a blkcg.
 * When this count goes to zero, all active wb has finished so the
 * blkcg can continue destruction by calling blkcg_destroy_blkgs().
 * This work may occur in cgwb_release_workfn() on the cgwb_release
 * workqueue.
 */


This is used to track the number of active wb's related to a blkcg.
When this count goes to zero, all active wb has finished so the
blkcg can continue destruction by calling blkcg_destroy_blkgs().
This work may occur in cgwb_release_workfn() on the cgwb_release
workqueue.
This is used to track the number of active wb ' s related to a blkcg . When this count goes to zero all active wb has finished so the blkcg can continue destruction by calling blkcg_destroy_blkgs () . This work may occur in cgwb_release_workfn () on the cgwb_release workqueue .
static inline void blkcg_cgwb_put(struct blkcg *blkcg)
{
	if (refcount_dec_and_test(&blkcg->cgwb_refcnt))
		blkcg_destroy_blkgs(blkcg);
}
static inline void blkcg_cgwb_put ( struct blkcg * blkcg ) { if ( refcount_dec_and_test ( & blkcg -> cgwb_refcnt ) ) blkcg_destroy_blkgs ( blkcg ) ; }
blkcg_cgwb_put - put a reference for @blkcg->cgwb_list
 @blkcg: blkcg of interest
blkcg_cgwb_put - put a reference for @blkcg - > cgwb_list @blkcg : blkcg of interest