x86/resctrl: Remove unused struct mbm_state::chunks_bw

Nothing reads struct mbm_states's chunks_bw value, its a copy of
chunks. Remove it.
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Link: https://lkml.kernel.org/r/20200708163929.2783-2-james.morse@arm.com

arch/x86/kernel/cpu/resctrl/internal.h

@@ -283,7 +283,6 @@ struct rftype {
  * struct mbm_state - status for each MBM counter in each domain
  * @chunks:	Total data moved (multiply by rdt_group.mon_scale to get bytes)
  * @prev_msr	Value of IA32_QM_CTR for this RMID last time we read it
- * @chunks_bw	Total local data moved. Used for bandwidth calculation
  * @prev_bw_msr:Value of previous IA32_QM_CTR for bandwidth counting
  * @prev_bw	The most recent bandwidth in MBps
  * @delta_bw	Difference between the current and previous bandwidth
@@ -292,7 +291,6 @@ struct rftype {
 struct mbm_state {
 	u64	chunks;
 	u64	prev_msr;
-	u64	chunks_bw;
 	u64	prev_bw_msr;
 	u32	prev_bw;
 	u32	delta_bw;

arch/x86/kernel/cpu/resctrl/monitor.c

@@ -279,8 +279,7 @@ static void mbm_bw_count(u32 rmid, struct rmid_read *rr)
 		return;
 
 	chunks = mbm_overflow_count(m->prev_bw_msr, tval, rr->r->mbm_width);
-	m->chunks_bw += chunks;
-	m->chunks = m->chunks_bw;
+	m->chunks += chunks;
 	cur_bw = (chunks * r->mon_scale) >> 20;
 
 	if (m->delta_comp)