[PATCH 1/3] selftests/resctrl: Introduced linked list management for IMC counters

[Yifan Wu]

Added linked list based management for IMC counter configurations,
allowing the system to dynamically allocate and clean up resources based on
actual hardware capabilities.

Signed-off-by: Yifan Wu <wuyifan50@xxxxxxxxxx>
---
 tools/testing/selftests/resctrl/resctrl.h     |  1 +
 tools/testing/selftests/resctrl/resctrl_val.c | 25 +++++++++++++++++++
 2 files changed, 26 insertions(+)

diff --git a/tools/testing/selftests/resctrl/resctrl.h b/tools/testing/selftests/resctrl/resctrl.h
index 175101022bf3..29c9f76132f0 100644
--- a/tools/testing/selftests/resctrl/resctrl.h
+++ b/tools/testing/selftests/resctrl/resctrl.h
@@ -24,6 +24,7 @@
 #include <linux/perf_event.h>
 #include <linux/compiler.h>
 #include <linux/bits.h>
+#include  <linux/list.h>
 #include "kselftest.h"
 
 #define MB			(1024 * 1024)
diff --git a/tools/testing/selftests/resctrl/resctrl_val.c b/tools/testing/selftests/resctrl/resctrl_val.c
index f20d2194c35f..ac58d3862281 100644
--- a/tools/testing/selftests/resctrl/resctrl_val.c
+++ b/tools/testing/selftests/resctrl/resctrl_val.c
@@ -28,6 +28,7 @@ struct membw_read_format {
 };
 
 struct imc_counter_config {
+	struct list_head imc_list;
 	__u32 type;
 	__u64 event;
 	__u64 umask;
@@ -38,6 +39,7 @@ struct imc_counter_config {
 static char mbm_total_path[1024];
 static int imcs;
 static struct imc_counter_config imc_counters_config[MAX_IMCS];
+LIST_HEAD(imc_counters_configs);
 static const struct resctrl_test *current_test;
 
 static void read_mem_bw_initialize_perf_event_attr(int i)
@@ -235,6 +237,7 @@ static int read_from_imc_dir(char *imc_dir, unsigned int *count)
  */
 static int num_of_imcs(void)
 {
+	struct imc_counter_config *imc_counters_config;
 	char imc_dir[512], *temp;
 	unsigned int count = 0;
 	struct dirent *ep;
@@ -263,14 +266,23 @@ static int num_of_imcs(void)
 			 * first character is a numerical digit or not.
 			 */
 			if (temp[0] >= '0' && temp[0] <= '9') {
+				imc_counters_config = malloc(sizeof(struct imc_counter_config));
+				if (!imc_counters_config) {
+					ksft_print_msg("Unable to allocate memory for iMC counters\n");
+
+					return -1;
+				}
+				memset(imc_counters_config, 0, sizeof(struct imc_counter_config));
 				sprintf(imc_dir, "%s/%s/", DYN_PMU_PATH,
 					ep->d_name);
 				ret = read_from_imc_dir(imc_dir, &count);
 				if (ret) {
+					free(imc_counters_config);
 					closedir(dp);
 
 					return ret;
 				}
+				list_add(&imc_counters_config->imc_list, &imc_counters_configs);
 			}
 		}
 		closedir(dp);
@@ -303,6 +315,19 @@ int initialize_read_mem_bw_imc(void)
 	return 0;
 }
 
+void cleanup_read_mem_bw_imc(void)
+{
+	struct imc_counter_config *next_imc_counters_config;
+	struct imc_counter_config *imc_counters_config;
+
+	list_for_each_entry_safe(imc_counters_config, next_imc_counters_config,
+				 &imc_counters_configs, imc_list) {
+		list_del(&imc_counters_config->imc_list);
+		free(imc_counters_config);
+	}
+	INIT_LIST_HEAD(&imc_counters_configs);
+}
+
 static void perf_close_imc_read_mem_bw(void)
 {
 	int mc;
-- 
2.33.0