[PATCH v2 1/6] 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/mba_test.c    |  1 +
 tools/testing/selftests/resctrl/mbm_test.c    |  1 +
 tools/testing/selftests/resctrl/resctrl.h     |  2 ++
 tools/testing/selftests/resctrl/resctrl_val.c | 20 +++++++++++++++++++
 4 files changed, 24 insertions(+)

diff --git a/tools/testing/selftests/resctrl/mba_test.c b/tools/testing/selftests/resctrl/mba_test.c
index 39cee9898359..4bb1a82eb195 100644
--- a/tools/testing/selftests/resctrl/mba_test.c
+++ b/tools/testing/selftests/resctrl/mba_test.c
@@ -166,6 +166,7 @@ static int check_results(void)
 
 static void mba_test_cleanup(void)
 {
+	cleanup_read_mem_bw_imc();
 	remove(RESULT_FILE_NAME);
 }
 
diff --git a/tools/testing/selftests/resctrl/mbm_test.c b/tools/testing/selftests/resctrl/mbm_test.c
index 6dbbc3b76003..68c89f50a34a 100644
--- a/tools/testing/selftests/resctrl/mbm_test.c
+++ b/tools/testing/selftests/resctrl/mbm_test.c
@@ -125,6 +125,7 @@ static int mbm_measure(const struct user_params *uparams,
 
 static void mbm_test_cleanup(void)
 {
+	cleanup_read_mem_bw_imc();
 	remove(RESULT_FILE_NAME);
 }
 
diff --git a/tools/testing/selftests/resctrl/resctrl.h b/tools/testing/selftests/resctrl/resctrl.h
index 175101022bf3..a7556cdae0de 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)
@@ -183,6 +184,7 @@ void mem_flush(unsigned char *buf, size_t buf_size);
 void fill_cache_read(unsigned char *buf, size_t buf_size, bool once);
 ssize_t get_fill_buf_size(int cpu_no, const char *cache_type);
 int initialize_read_mem_bw_imc(void);
+void cleanup_read_mem_bw_imc(void);
 int measure_read_mem_bw(const struct user_params *uparams,
 			struct resctrl_val_param *param, pid_t bm_pid);
 void initialize_mem_bw_resctrl(const struct resctrl_val_param *param,
diff --git a/tools/testing/selftests/resctrl/resctrl_val.c b/tools/testing/selftests/resctrl/resctrl_val.c
index f20d2194c35f..d9ae24e9d971 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 entry;
 	__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_list);
 static const struct resctrl_test *current_test;
 
 static void read_mem_bw_initialize_perf_event_attr(int i)
@@ -113,6 +115,7 @@ static int parse_imc_read_bw_events(char *imc_dir, unsigned int type,
 				    unsigned int *count)
 {
 	char imc_events_dir[PATH_MAX], imc_counter_cfg[PATH_MAX];
+	struct imc_counter_config *imc_counter;
 	unsigned int orig_count = *count;
 	char cas_count_cfg[1024];
 	struct dirent *ep;
@@ -167,11 +170,17 @@ static int parse_imc_read_bw_events(char *imc_dir, unsigned int type,
 			ksft_print_msg("Maximum iMC count exceeded\n");
 			goto out_close;
 		}
+		imc_counter = calloc(1, sizeof(*imc_counter));
+		if (!imc_counter) {
+			ksft_perror("Unable to allocate memory for iMC counters\n");
+			goto out_close;
+		}
 
 		imc_counters_config[*count].type = type;
 		get_read_event_and_umask(cas_count_cfg, *count);
 		/* Do not fail after incrementing *count. */
 		*count += 1;
+		list_add(&imc_counter->entry, &imc_counters_list);
 	}
 	if (*count == orig_count) {
 		ksft_print_msg("Unable to find events in %s\n", imc_events_dir);
@@ -303,6 +312,17 @@ int initialize_read_mem_bw_imc(void)
 	return 0;
 }
 
+void cleanup_read_mem_bw_imc(void)
+{
+	struct imc_counter_config *imc_counter, *tmp;
+
+	list_for_each_entry_safe(imc_counter, tmp,
+				 &imc_counters_list, entry) {
+		list_del(&imc_counter->entry);
+		free(imc_counter);
+	}
+}
+
 static void perf_close_imc_read_mem_bw(void)
 {
 	int mc;
-- 
2.43.0