[PATCH 20/22] selftests/resctrl: Split measure_cache_vals() function

[Ilpo Järvinen]

The measure_cache_vals() function does a different thing depending on
the test case that called it:
  - For CAT, it measures LLC perf misses 2.
  - For CMT, it measures LLC occupancy through resctrl.

Split these two functionalities such that CMT test calls a new function
called measure_llc_resctrl() to get LLC occupancy through resctrl and
CAT test directly calls get_llc_perf().

Co-developed-by: Fenghua Yu <fenghua.yu@xxxxxxxxx>
Signed-off-by: Fenghua Yu <fenghua.yu@xxxxxxxxx>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@xxxxxxxxxxxxxxx>
---
 tools/testing/selftests/resctrl/cache.c       | 37 ++++++++-----------
 tools/testing/selftests/resctrl/resctrl.h     |  2 +-
 tools/testing/selftests/resctrl/resctrl_val.c |  2 +-
 3 files changed, 17 insertions(+), 24 deletions(-)

diff --git a/tools/testing/selftests/resctrl/cache.c b/tools/testing/selftests/resctrl/cache.c
index 835d5a892524..225ba589d230 100644
--- a/tools/testing/selftests/resctrl/cache.c
+++ b/tools/testing/selftests/resctrl/cache.c
@@ -199,35 +199,20 @@ static int print_results_cache(char *filename, int bm_pid,
 	return 0;
 }
 
-int measure_cache_vals(struct resctrl_val_param *param, int bm_pid)
+int measure_llc_resctrl(struct resctrl_val_param *param, int bm_pid)
 {
-	unsigned long llc_perf_miss = 0, llc_occu_resc = 0, llc_value = 0;
+	unsigned long llc_occu_resc = 0;
 	int ret;
 
-	/*
-	 * Measure cache miss from perf.
-	 */
-	if (!strncmp(param->resctrl_val, CAT_STR, sizeof(CAT_STR))) {
-		ret = get_llc_perf(&llc_perf_miss);
-		if (ret < 0)
-			return ret;
-		llc_value = llc_perf_miss;
-	}
-
 	/*
 	 * Measure llc occupancy from resctrl.
 	 */
-	if (!strncmp(param->resctrl_val, CMT_STR, sizeof(CMT_STR))) {
-		ret = get_llc_occu_resctrl(&llc_occu_resc);
-		if (ret < 0)
-			return ret;
-		llc_value = llc_occu_resc;
-	}
-	ret = print_results_cache(param->filename, bm_pid, llc_value);
-	if (ret)
+	ret = get_llc_occu_resctrl(&llc_occu_resc);
+	if (ret < 0)
 		return ret;
 
-	return 0;
+	ret = print_results_cache(param->filename, bm_pid, llc_occu_resc);
+	return ret;
 }
 
 /*
@@ -241,6 +226,7 @@ int cat_val(struct resctrl_val_param *param)
 {
 	int memflush = 1, operation = 0, ret = 0;
 	char *resctrl_val = param->resctrl_val;
+	unsigned long llc_perf_miss = 0;
 	pid_t bm_pid;
 
 	if (strcmp(param->filename, "") == 0)
@@ -281,7 +267,14 @@ int cat_val(struct resctrl_val_param *param)
 		}
 
 		sleep(1);
-		ret = measure_cache_vals(param, bm_pid);
+
+		/* Measure cache miss from perf */
+		ret = get_llc_perf(&llc_perf_miss);
+		if (ret)
+			break;
+
+		ret = print_results_cache(param->filename, bm_pid,
+					  llc_perf_miss);
 		if (ret)
 			break;
 	}
diff --git a/tools/testing/selftests/resctrl/resctrl.h b/tools/testing/selftests/resctrl/resctrl.h
index 7609d5765fcd..028b979c28fb 100644
--- a/tools/testing/selftests/resctrl/resctrl.h
+++ b/tools/testing/selftests/resctrl/resctrl.h
@@ -124,7 +124,7 @@ int cmt_resctrl_val(int cpu_no, int n, char **benchmark_cmd);
 unsigned int count_bits(unsigned long n);
 void cmt_test_cleanup(void);
 int get_core_sibling(int cpu_no);
-int measure_cache_vals(struct resctrl_val_param *param, int bm_pid);
+int measure_llc_resctrl(struct resctrl_val_param *param, int bm_pid);
 int show_cache_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,
diff --git a/tools/testing/selftests/resctrl/resctrl_val.c b/tools/testing/selftests/resctrl/resctrl_val.c
index 8ed6ce565b13..2904bafba4aa 100644
--- a/tools/testing/selftests/resctrl/resctrl_val.c
+++ b/tools/testing/selftests/resctrl/resctrl_val.c
@@ -749,7 +749,7 @@ int resctrl_val(char **benchmark_cmd, struct resctrl_val_param *param)
 				break;
 		} else if (!strncmp(resctrl_val, CMT_STR, sizeof(CMT_STR))) {
 			sleep(1);
-			ret = measure_cache_vals(param, bm_pid);
+			ret = measure_llc_resctrl(param, bm_pid);
 			if (ret)
 				break;
 		}
-- 
2.30.2