NR_USAGE_SLOTS    496 block/blk-iocost.c 	u32				usages[NR_USAGE_SLOTS];
NR_USAGE_SLOTS   1447 block/blk-iocost.c 			iocg->usage_idx = (iocg->usage_idx + 1) % NR_USAGE_SLOTS;
NR_USAGE_SLOTS   1513 block/blk-iocost.c 		for (i = 0, usage = 0; i < NR_USAGE_SLOTS; i++) {