[PATCH v2 3/4] selftests/resctrl: Add support for MBM and MBA tests on AMD

[Babu Moger <babu.moger@xxxxxxx>]

Add support to read UMC (Unified Memory Controller) perf events to compare
the numbers with QoS monitor for AMD.

Signed-off-by: Babu Moger <babu.moger@xxxxxxx>
---
 tools/testing/selftests/resctrl/resctrl_val.c | 67 ++++++++++++++++---
 1 file changed, 59 insertions(+), 8 deletions(-)

diff --git a/tools/testing/selftests/resctrl/resctrl_val.c b/tools/testing/selftests/resctrl/resctrl_val.c
index e3b09128ec3d..d90d3196d7b5 100644
--- a/tools/testing/selftests/resctrl/resctrl_val.c
+++ b/tools/testing/selftests/resctrl/resctrl_val.c
@@ -11,6 +11,7 @@
 #include "resctrl.h"
 
 #define UNCORE_IMC		"uncore_imc"
+#define AMD_UMC			"amd_umc"
 #define READ_FILE_NAME		"events/cas_count_read"
 #define WRITE_FILE_NAME		"events/cas_count_write"
 #define DYN_PMU_PATH		"/sys/bus/event_source/devices"
@@ -146,6 +147,47 @@ static int open_perf_event(int i, int cpu_no, int j)
 	return 0;
 }
 
+/* Get type and config (read and write) of an UMC counter */
+static int read_from_umc_dir(char *umc_dir, int count)
+{
+	char umc_counter_type[PATH_MAX];
+	FILE *fp;
+
+	/* Get type of iMC counter */
+	sprintf(umc_counter_type, "%s%s", umc_dir, "type");
+	fp = fopen(umc_counter_type, "r");
+	if (!fp) {
+		ksft_perror("Failed to open imc counter type file");
+		return -1;
+	}
+
+	if (fscanf(fp, "%u", &imc_counters_config[count][READ].type) <= 0) {
+		ksft_perror("Could not get imc type");
+		fclose(fp);
+		return -1;
+	}
+
+	fclose(fp);
+
+	imc_counters_config[count][WRITE].type =
+		imc_counters_config[count][READ].type;
+
+	/*
+	 * Setup the event and umasks for UMC events
+	 * Number of CAS commands sent for reads:
+	 * EventCode = 0x0a, umask = 0x1
+	 * Number of CAS commands sent for writes:
+	 * EventCode = 0x0a, umask = 0x2
+	 */
+	imc_counters_config[count][READ].event = 0xa;
+	imc_counters_config[count][READ].umask = 0x1;
+
+	imc_counters_config[count][WRITE].event = 0xa;
+	imc_counters_config[count][WRITE].umask = 0x2;
+
+	return 0;
+}
+
 /* Get type and config (read and write) of an iMC counter */
 static int read_from_imc_dir(char *imc_dir, int count)
 {
@@ -233,6 +275,9 @@ static int num_of_mem_controllers(void)
 	if (vendor == ARCH_INTEL) {
 		sysfs_name = UNCORE_IMC;
 		size = sizeof(UNCORE_IMC);
+	} else if (vendor == ARCH_AMD) {
+		sysfs_name = AMD_UMC;
+		size = sizeof(AMD_UMC);
 	} else {
 		perror("Unsupported Vendor!\n");
 		return -1;
@@ -246,11 +291,12 @@ static int num_of_mem_controllers(void)
 				continue;
 
 			/*
-			 * imc counters are named as "uncore_imc_<n>", hence
-			 * increment the pointer to point to <n>. Note that
-			 * sizeof(UNCORE_IMC) would count for null character as
-			 * well and hence the last underscore character in
-			 * uncore_imc'_' need not be counted.
+			 * Intel imc counters are named as "uncore_imc_<n>",
+			 * hence increment the pointer to point to <n>.
+			 * Note that sizeof(UNCORE_IMC) would count for null
+			 * character as well and hence the last underscore
+			 * character in uncore_imc'_' need not be counted.
+			 * For AMD, it will be amd_umc_<n>.
 			 */
 			temp = temp + size;
 
@@ -262,7 +308,11 @@ static int num_of_mem_controllers(void)
 			if (temp[0] >= '0' && temp[0] <= '9') {
 				sprintf(imc_dir, "%s/%s/", DYN_PMU_PATH,
 					ep->d_name);
-				ret = read_from_imc_dir(imc_dir, count);
+				if (vendor == ARCH_INTEL)
+					ret = read_from_imc_dir(imc_dir, count);
+				else
+					ret = read_from_umc_dir(imc_dir, count);
+
 				if (ret) {
 					closedir(dp);
 
@@ -273,8 +323,9 @@ static int num_of_mem_controllers(void)
 		}
 		closedir(dp);
 		if (count == 0) {
-			ksft_print_msg("Unable to find iMC counters\n");
-
+			ksft_print_msg("Unable to find iMC/UMC counters\n");
+			if (vendor == ARCH_AMD)
+				ksft_print_msg("Try loading amd_uncore module\n");
 			return -1;
 		}
 	} else {
-- 
2.34.1