selftests/resctrl: Add Cache QoS Monitoring (CQM) selftest

Cache QoS Monitoring (CQM) selftest starts stressful cache benchmark
with specified size of memory to access the cache. Last Level cache
occupancy reported by CQM should be close to the size of the memory.

Co-developed-by: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Signed-off-by: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Co-developed-by: Babu Moger <babu.moger@amd.com>
Signed-off-by: Babu Moger <babu.moger@amd.com>
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

1 files changed, 185 insertions, 8 deletions

diff --git a/tools/testing/selftests/resctrl/resctrlfs.c b/tools/testing/selftests/resctrl/resctrlfs.c
index 07c8394b427f..9c050a6c1723 100644
--- a/tools/testing/selftests/resctrl/resctrlfs.c
+++ b/tools/testing/selftests/resctrl/resctrlfs.c
@@ -49,6 +49,8 @@ static int find_resctrl_mount(char *buffer)
 	return -ENOENT;
 }
 
+char cbm_mask[256];
+
 /*
  * remount_resctrlfs - Remount resctrl FS at /sys/fs/resctrl
  * @mum_resctrlfs:	Should the resctrl FS be remounted?
@@ -131,6 +133,145 @@ int get_resource_id(int cpu_no, int *resource_id)
 }
 
 /*
+ * get_cache_size - Get cache size for a specified CPU
+ * @cpu_no:	CPU number
+ * @cache_type:	Cache level L2/L3
+ * @cache_size:	pointer to cache_size
+ *
+ * Return: = 0 on success, < 0 on failure.
+ */
+int get_cache_size(int cpu_no, char *cache_type, unsigned long *cache_size)
+{
+	char cache_path[1024], cache_str[64];
+	int length, i, cache_num;
+	FILE *fp;
+
+	if (!strcmp(cache_type, "L3")) {
+		cache_num = 3;
+	} else if (!strcmp(cache_type, "L2")) {
+		cache_num = 2;
+	} else {
+		perror("Invalid cache level");
+		return -1;
+	}
+
+	sprintf(cache_path, "/sys/bus/cpu/devices/cpu%d/cache/index%d/size",
+		cpu_no, cache_num);
+	fp = fopen(cache_path, "r");
+	if (!fp) {
+		perror("Failed to open cache size");
+
+		return -1;
+	}
+	if (fscanf(fp, "%s", cache_str) <= 0) {
+		perror("Could not get cache_size");
+		fclose(fp);
+
+		return -1;
+	}
+	fclose(fp);
+
+	length = (int)strlen(cache_str);
+
+	*cache_size = 0;
+
+	for (i = 0; i < length; i++) {
+		if ((cache_str[i] >= '0') && (cache_str[i] <= '9'))
+
+			*cache_size = *cache_size * 10 + (cache_str[i] - '0');
+
+		else if (cache_str[i] == 'K')
+
+			*cache_size = *cache_size * 1024;
+
+		else if (cache_str[i] == 'M')
+
+			*cache_size = *cache_size * 1024 * 1024;
+
+		else
+			break;
+	}
+
+	return 0;
+}
+
+#define CORE_SIBLINGS_PATH	"/sys/bus/cpu/devices/cpu"
+
+/*
+ * get_cbm_mask - Get cbm mask for given cache
+ * @cache_type:	Cache level L2/L3
+ *
+ * Mask is stored in cbm_mask which is global variable.
+ *
+ * Return: = 0 on success, < 0 on failure.
+ */
+int get_cbm_mask(char *cache_type)
+{
+	char cbm_mask_path[1024];
+	FILE *fp;
+
+	sprintf(cbm_mask_path, "%s/%s/cbm_mask", CBM_MASK_PATH, cache_type);
+
+	fp = fopen(cbm_mask_path, "r");
+	if (!fp) {
+		perror("Failed to open cache level");
+
+		return -1;
+	}
+	if (fscanf(fp, "%s", cbm_mask) <= 0) {
+		perror("Could not get max cbm_mask");
+		fclose(fp);
+
+		return -1;
+	}
+	fclose(fp);
+
+	return 0;
+}
+
+/*
+ * get_core_sibling - Get sibling core id from the same socket for given CPU
+ * @cpu_no:	CPU number
+ *
+ * Return:	> 0 on success, < 0 on failure.
+ */
+int get_core_sibling(int cpu_no)
+{
+	char core_siblings_path[1024], cpu_list_str[64];
+	int sibling_cpu_no = -1;
+	FILE *fp;
+
+	sprintf(core_siblings_path, "%s%d/topology/core_siblings_list",
+		CORE_SIBLINGS_PATH, cpu_no);
+
+	fp = fopen(core_siblings_path, "r");
+	if (!fp) {
+		perror("Failed to open core siblings path");
+
+		return -1;
+	}
+	if (fscanf(fp, "%s", cpu_list_str) <= 0) {
+		perror("Could not get core_siblings list");
+		fclose(fp);
+
+		return -1;
+	}
+	fclose(fp);
+
+	char *token = strtok(cpu_list_str, "-,");
+
+	while (token) {
+		sibling_cpu_no = atoi(token);
+		/* Skipping core 0 as we don't want to run test on core 0 */
+		if (sibling_cpu_no != 0)
+			break;
+		token = strtok(NULL, "-,");
+	}
+
+	return sibling_cpu_no;
+}
+
+/*
  * taskset_benchmark - Taskset PID (i.e. benchmark) to a specified cpu
  * @bm_pid:	PID that should be binded
  * @cpu_no:	CPU number at which the PID would be binded
@@ -164,9 +305,10 @@ int taskset_benchmark(pid_t bm_pid, int cpu_no)
  */
 void run_benchmark(int signum, siginfo_t *info, void *ucontext)
 {
-	unsigned long span;
-	int operation, ret;
+	int operation, ret, malloc_and_init_memory, memflush;
+	unsigned long span, buffer_span;
 	char **benchmark_cmd;
+	char resctrl_val[64];
 	FILE *fp;
 
 	benchmark_cmd = info->si_ptr;
@@ -182,8 +324,18 @@ void run_benchmark(int signum, siginfo_t *info, void *ucontext)
 	if (strcmp(benchmark_cmd[0], "fill_buf") == 0) {
 		/* Execute default fill_buf benchmark */
 		span = strtoul(benchmark_cmd[1], NULL, 10);
+		malloc_and_init_memory = atoi(benchmark_cmd[2]);
+		memflush =  atoi(benchmark_cmd[3]);
 		operation = atoi(benchmark_cmd[4]);
-		if (run_fill_buf(span, 1, 1, operation, NULL))
+		sprintf(resctrl_val, "%s", benchmark_cmd[5]);
+
+		if (strcmp(resctrl_val, "cqm") != 0)
+			buffer_span = span * MB;
+		else
+			buffer_span = span;
+
+		if (run_fill_buf(buffer_span, malloc_and_init_memory, memflush,
+				 operation, resctrl_val))
 			fprintf(stderr, "Error in running fill buffer\n");
 	} else {
 		/* Execute specified benchmark */
@@ -210,6 +362,14 @@ static int create_grp(const char *grp_name, char *grp, const char *parent_grp)
 	struct dirent *ep;
 	DIR *dp;
 
+	/*
+	 * At this point, we are guaranteed to have resctrl FS mounted and if
+	 * length of grp_name == 0, it means, user wants to use root con_mon
+	 * grp, so do nothing
+	 */
+	if (strlen(grp_name) == 0)
+		return 0;
+
 	/* Check if requested grp exists or not */
 	dp = opendir(parent_grp);
 	if (dp) {
@@ -293,9 +453,10 @@ int write_bm_pid_to_resctrl(pid_t bm_pid, char *ctrlgrp, char *mongrp,
 	if (ret)
 		goto out;
 
-	/* Create mon grp and write pid into it for "mbm" test */
-	if ((strcmp(resctrl_val, "mbm") == 0)) {
-		if (mongrp) {
+	/* Create mon grp and write pid into it for "mbm" and "cqm" test */
+	if ((strcmp(resctrl_val, "cqm") == 0) ||
+	    (strcmp(resctrl_val, "mbm") == 0)) {
+		if (strlen(mongrp)) {
 			sprintf(monitorgroup_p, "%s/mon_groups", controlgroup);
 			sprintf(monitorgroup, "%s/%s", monitorgroup_p, mongrp);
 			ret = create_grp(mongrp, monitorgroup, monitorgroup_p);
@@ -339,7 +500,8 @@ int write_schemata(char *ctrlgrp, char *schemata, int cpu_no, char *resctrl_val)
 	int resource_id, ret = 0;
 	FILE *fp;
 
-	if (strcmp(resctrl_val, "mba") != 0)
+	if ((strcmp(resctrl_val, "mba") != 0) &&
+	    (strcmp(resctrl_val, "cqm") != 0))
 		return -ENOENT;
 
 	if (!schemata) {
@@ -360,7 +522,10 @@ int write_schemata(char *ctrlgrp, char *schemata, int cpu_no, char *resctrl_val)
 	else
 		sprintf(controlgroup, "%s/schemata", RESCTRL_PATH);
 
-	sprintf(schema, "%s%d%c%s", "MB:", resource_id, '=', schemata);
+	if (!strcmp(resctrl_val, "cqm"))
+		sprintf(schema, "%s%d%c%s", "L3:", resource_id, '=', schemata);
+	if (strcmp(resctrl_val, "mba") == 0)
+		sprintf(schema, "%s%d%c%s", "MB:", resource_id, '=', schemata);
 
 	fp = fopen(controlgroup, "w");
 	if (!fp) {
@@ -537,3 +702,15 @@ int perf_event_open(struct perf_event_attr *hw_event, pid_t pid, int cpu,
 		      group_fd, flags);
 	return ret;
 }
+
+unsigned int count_bits(unsigned long n)
+{
+	unsigned int count = 0;
+
+	while (n) {
+		count += n & 1;
+		n >>= 1;
+	}
+
+	return count;
+}