selftests/resctrl: Simplify mem bandwidth file code for MBA & MBM tests

initialize_mem_bw_resctrl() and set_mbm_path() contain complicated set
of conditions, each yielding different file to be opened to measure
memory bandwidth through resctrl FS. In practice, only two of them are
used. For MBA test, ctrlgrp is always provided, and for MBM test both
ctrlgrp and mongrp are set.

The file used differ between MBA/MBM test, however, MBM test
unnecessarily create monitor group because resctrl FS already provides
monitoring interface underneath any ctrlgrp too, which is what the MBA
selftest uses.

Consolidate memory bandwidth file used to the one used by the MBA
selftest. Remove all unused branches opening other files to simplify
the code.

Suggested-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Tested-by: Babu Moger <babu.moger@amd.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

Author: ij-intel

tools/testing/selftests/resctrl/mbm_test.c

@@ -115,7 +115,6 @@ static int mbm_run_test(const struct resctrl_test *test, const struct user_param
 	struct resctrl_val_param param = {
 		.resctrl_val	= MBM_STR,
 		.ctrlgrp	= "c1",
-		.mongrp		= "m1",
 		.filename	= RESULT_FILE_NAME,
 		.bw_report	= "reads",
 		.setup		= mbm_setup

tools/testing/selftests/resctrl/resctrl_val.c

@@ -19,18 +19,10 @@
 #define MAX_TOKENS		5
 #define READ			0
 #define WRITE			1
-#define CON_MON_MBM_LOCAL_BYTES_PATH				\
-	"%s/%s/mon_groups/%s/mon_data/mon_L3_%02d/mbm_local_bytes"
 
 #define CON_MBM_LOCAL_BYTES_PATH		\
 	"%s/%s/mon_data/mon_L3_%02d/mbm_local_bytes"
 
-#define MON_MBM_LOCAL_BYTES_PATH		\
-	"%s/mon_groups/%s/mon_data/mon_L3_%02d/mbm_local_bytes"
-
-#define MBM_LOCAL_BYTES_PATH			\
-	"%s/mon_data/mon_L3_%02d/mbm_local_bytes"
-
 #define CON_MON_LCC_OCCUP_PATH		\
 	"%s/%s/mon_groups/%s/mon_data/mon_L3_%02d/llc_occupancy"
 
@@ -430,43 +422,15 @@ static int get_mem_bw_imc(char *bw_report, float *bw_imc)
 	return 0;
 }
 
-void set_mbm_path(const char *ctrlgrp, const char *mongrp, int domain_id)
-{
-	if (ctrlgrp && mongrp)
-		sprintf(mbm_total_path, CON_MON_MBM_LOCAL_BYTES_PATH,
-			RESCTRL_PATH, ctrlgrp, mongrp, domain_id);
-	else if (!ctrlgrp && mongrp)
-		sprintf(mbm_total_path, MON_MBM_LOCAL_BYTES_PATH, RESCTRL_PATH,
-			mongrp, domain_id);
-	else if (ctrlgrp && !mongrp)
-		sprintf(mbm_total_path, CON_MBM_LOCAL_BYTES_PATH, RESCTRL_PATH,
-			ctrlgrp, domain_id);
-	else if (!ctrlgrp && !mongrp)
-		sprintf(mbm_total_path, MBM_LOCAL_BYTES_PATH, RESCTRL_PATH,
-			domain_id);
-}
-
 /*
  * initialize_mem_bw_resctrl:	Appropriately populate "mbm_total_path"
  * @ctrlgrp:			Name of the control monitor group (con_mon grp)
- * @mongrp:			Name of the monitor group (mon grp)
  * @domain_id:			Domain ID (cache ID; for MB, L3 cache ID)
- * @resctrl_val:		Resctrl feature (Eg: mbm, mba.. etc)
  */
-static void initialize_mem_bw_resctrl(const char *ctrlgrp, const char *mongrp,
-				      int domain_id, char *resctrl_val)
+static void initialize_mem_bw_resctrl(const char *ctrlgrp, int domain_id)
 {
-	if (!strncmp(resctrl_val, MBM_STR, sizeof(MBM_STR)))
-		set_mbm_path(ctrlgrp, mongrp, domain_id);
-
-	if (!strncmp(resctrl_val, MBA_STR, sizeof(MBA_STR))) {
-		if (ctrlgrp)
-			sprintf(mbm_total_path, CON_MBM_LOCAL_BYTES_PATH,
-				RESCTRL_PATH, ctrlgrp, domain_id);
-		else
-			sprintf(mbm_total_path, MBM_LOCAL_BYTES_PATH,
-				RESCTRL_PATH, domain_id);
-	}
+	sprintf(mbm_total_path, CON_MBM_LOCAL_BYTES_PATH, RESCTRL_PATH,
+		ctrlgrp, domain_id);
 }
 
 /*
@@ -867,8 +831,7 @@ int resctrl_val(const struct resctrl_test *test,
 		if (ret)
 			goto out;
 
-		initialize_mem_bw_resctrl(param->ctrlgrp, param->mongrp,
-					  domain_id, resctrl_val);
+		initialize_mem_bw_resctrl(param->ctrlgrp, domain_id);
 	} else if (!strncmp(resctrl_val, CMT_STR, sizeof(CMT_STR)))
 		initialize_llc_occu_resctrl(param->ctrlgrp, param->mongrp,
 					    domain_id, resctrl_val);