diff mbox series

[v3,09/16] selftests/resctrl: Simplify mem bandwidth file code for MBA & MBM tests

Message ID 20240408163247.3224-10-ilpo.jarvinen@linux.intel.com (mailing list archive)
State New
Headers show
Series selftests/resctrl: resctrl_val() related cleanups & improvements | expand

Commit Message

Ilpo Järvinen April 8, 2024, 4:32 p.m. UTC 
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>
---

v3:
- New patch
---
 tools/testing/selftests/resctrl/resctrl_val.c | 45 ++-----------------
 1 file changed, 4 insertions(+), 41 deletions(-)

Comments

Reinette Chatre April 25, 2024, 4:38 a.m. UTC | #1 
Hi Ilpo,

On 4/8/2024 9:32 AM, Ilpo Järvinen wrote:
> 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.

This is a good change but it seems incomplete to me. As changelog states
MBM creates monitor group unnecessarily, but from what I can tell it continues
to do so after this change. It is also optimized in patch 16, which I think
may end up being dropped as part of cleaning this up (here and for the CMT test).

Reinette
diff mbox series

Patch

diff --git a/tools/testing/selftests/resctrl/resctrl_val.c b/tools/testing/selftests/resctrl/resctrl_val.c
index e4ad60963b0d..e8e5c0f7f20b 100644
--- a/tools/testing/selftests/resctrl/resctrl_val.c
+++ b/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"
 
@@ -426,43 +418,15 @@  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);
 }
 
 /*
@@ -850,8 +814,7 @@  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);