selftests/resctrl: Add ->measure() callback to resctrl_val_param

The measurement done in resctrl_val() varies depending on test type.
The decision for how to measure is decided based on the string compare
to test name which is quite inflexible.

Add ->measure() callback into the struct resctrl_val_param to allow
each test to provide necessary code as a function which simplifies what
resctrl_val() has to do.
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>

tools/testing/selftests/resctrl/cmt_test.c

@@ -29,6 +29,13 @@ static int cmt_setup(const struct resctrl_test *test,
 	return 0;
 }
 
+static int cmt_measure(const struct user_params *uparams,
+		       struct resctrl_val_param *param, pid_t bm_pid)
+{
+	sleep(1);
+	return measure_llc_resctrl(param->filename, bm_pid);
+}
+
 static int show_results_info(unsigned long sum_llc_val, int no_of_bits,
 			     unsigned long cache_span, unsigned long max_diff,
 			     unsigned long max_diff_percent, unsigned long num_of_runs,
@@ -133,6 +140,7 @@ static int cmt_run_test(const struct resctrl_test *test, const struct user_param
 		.mask		= ~(long_mask << n) & long_mask,
 		.num_of_runs	= 0,
 		.setup		= cmt_setup,
+		.measure	= cmt_measure,
 	};
 
 	span = cache_portion_size(cache_total_size, param.mask, long_mask);

tools/testing/selftests/resctrl/mba_test.c

@@ -51,6 +51,12 @@ static int mba_setup(const struct resctrl_test *test,
 	return 0;
 }
 
+static int mba_measure(const struct user_params *uparams,
+		       struct resctrl_val_param *param, pid_t bm_pid)
+{
+	return measure_mem_bw(uparams, param, bm_pid);
+}
+
 static bool show_mba_info(unsigned long *bw_imc, unsigned long *bw_resc)
 {
 	int allocation, runs;
@@ -150,7 +156,8 @@ static int mba_run_test(const struct resctrl_test *test, const struct user_param
 		.mongrp		= "m1",
 		.filename	= RESULT_FILE_NAME,
 		.bw_report	= "reads",
-		.setup		= mba_setup
+		.setup		= mba_setup,
+		.measure	= mba_measure,
 	};
 	int ret;
 

tools/testing/selftests/resctrl/mbm_test.c

@@ -105,6 +105,12 @@ static int mbm_setup(const struct resctrl_test *test,
 	return ret;
 }
 
+static int mbm_measure(const struct user_params *uparams,
+		       struct resctrl_val_param *param, pid_t bm_pid)
+{
+	return measure_mem_bw(uparams, param, bm_pid);
+}
+
 static void mbm_test_cleanup(void)
 {
 	remove(RESULT_FILE_NAME);
@@ -117,7 +123,8 @@ static int mbm_run_test(const struct resctrl_test *test, const struct user_param
 		.ctrlgrp	= "c1",
 		.filename	= RESULT_FILE_NAME,
 		.bw_report	= "reads",
-		.setup		= mbm_setup
+		.setup		= mbm_setup,
+		.measure	= mbm_measure,
 	};
 	int ret;
 

tools/testing/selftests/resctrl/resctrl.h

@@ -87,6 +87,7 @@ struct resctrl_test {
  * @filename:		Name of file to which the o/p should be written
  * @bw_report:		Bandwidth report type (reads vs writes)
  * @setup:		Call back function to setup test environment
+ * @measure:		Callback that performs the measurement (a single test)
  */
 struct resctrl_val_param {
 	char		*resctrl_val;
@@ -99,6 +100,9 @@ struct resctrl_val_param {
 	int		(*setup)(const struct resctrl_test *test,
 				 const struct user_params *uparams,
 				 struct resctrl_val_param *param);
+	int		(*measure)(const struct user_params *uparams,
+				   struct resctrl_val_param *param,
+				   pid_t bm_pid);
 };
 
 struct perf_event_read {
@@ -145,6 +149,8 @@ unsigned char *alloc_buffer(size_t buf_size, int memflush);
 void mem_flush(unsigned char *buf, size_t buf_size);
 void fill_cache_read(unsigned char *buf, size_t buf_size, bool once);
 int run_fill_buf(size_t buf_size, int memflush, int op, bool once);
+int measure_mem_bw(const struct user_params *uparams,
+		   struct resctrl_val_param *param, pid_t bm_pid);
 int resctrl_val(const struct resctrl_test *test,
 		const struct user_params *uparams,
 		const char * const *benchmark_cmd,

tools/testing/selftests/resctrl/resctrl_val.c

@@ -606,8 +606,8 @@ static void initialize_llc_occu_resctrl(const char *ctrlgrp, const char *mongrp,
  * available. Compare the two values to validate resctrl value. It takes
  * 1 sec to measure the data.
  */
-static int measure_mem_bw(const struct user_params *uparams,
-			  struct resctrl_val_param *param, pid_t bm_pid)
+int measure_mem_bw(const struct user_params *uparams,
+		   struct resctrl_val_param *param, pid_t bm_pid)
 {
 	unsigned long bw_resc, bw_resc_start, bw_resc_end;
 	FILE *mem_bw_fp;
@@ -868,17 +868,9 @@ int resctrl_val(const struct resctrl_test *test,
 		if (ret < 0)
 			break;
 
-		if (!strncmp(resctrl_val, MBM_STR, sizeof(MBM_STR)) ||
-		    !strncmp(resctrl_val, MBA_STR, sizeof(MBA_STR))) {
-			ret = measure_mem_bw(uparams, param, bm_pid);
-			if (ret)
-				break;
-		} else if (!strncmp(resctrl_val, CMT_STR, sizeof(CMT_STR))) {
-			sleep(1);
-			ret = measure_llc_resctrl(param->filename, bm_pid);
-			if (ret)
-				break;
-		}
+		ret = param->measure(uparams, param, bm_pid);
+		if (ret)
+			break;
 	}
 
 out: