[RFC patch 7/9] selftests/resctrl: Add support for HiSilicon memory bandwidth measurement
From: Yifan Wu
Date: Tue Mar 03 2026 - 23:03:55 EST
This commit adds support for HiSilicon memory bandwidth measurement by
introducing vendor-specific implementations:
1. Counter Discovery for HiSilicon: A new function num_of_hisi_ddrc()
is implemented. It discovers the HiSilicon DDRC PMUs in the PMU path,
dynamically creating and linking counter structures into the global list
for each one found.
2. Support for config Perf Event Attribute: To adapt HiSilicon's perf
event configuration, struct imc_counter_config is augmented with a
__u64 config field, and get_read_event_and_umask() is updated to parse a
"config" token from the event files. The perf_event_attr configuration
logic now uses this config value if available, falling back to the
event/umask logic for Intel.
3. Resctrl Domain ID Discovery for MB: A new vendor-specific logic is
added to get_domain_id() in resctrlfs.c. On HiSilicon platforms, when the
resource is "MB", the domain ID is discovered by reading the NUMA Node
ID from the CPU's topology path (/sys/devices/system/cpu/cpuX/topology/),
as MPAM's Memory Bandwidth resource is scoped to NUMA domains.
4. Bandwidth Calculation Adjustment: The measure_read_mem_bw() function
is modified to handle the fundamental difference in reporting between
vendors: Intel's resctrl reports a cumulative historical delta value,
which must be converted to a rate division by MB. HiSilicon MPAM reports
a real-time value, which is used directly.
These changes collectively enable the selftests to accurately measure
memory bandwidth on HiSilicon platforms that implement MPAM.
Signed-off-by: Yifan Wu <wuyifan50@xxxxxxxxxx>
---
tools/testing/selftests/resctrl/resctrl_val.c | 67 ++++++++++++++++++-
tools/testing/selftests/resctrl/resctrlfs.c | 20 ++++++
2 files changed, 85 insertions(+), 2 deletions(-)
diff --git a/tools/testing/selftests/resctrl/resctrl_val.c b/tools/testing/selftests/resctrl/resctrl_val.c
index 75a3d359f16b..2c3df653e6ce 100644
--- a/tools/testing/selftests/resctrl/resctrl_val.c
+++ b/tools/testing/selftests/resctrl/resctrl_val.c
@@ -15,6 +15,8 @@
#define CON_MBM_LOCAL_BYTES_PATH \
"%s/%s/mon_data/mon_L3_%02d/mbm_local_bytes"
+#define CON_MBM_TOTAL_BYTES_PATH \
+ "%s/%s/mon_data/mon_MB_%02d/mbm_total_bytes"
struct membw_read_format {
__u64 value; /* The value of the event */
@@ -27,6 +29,7 @@ struct imc_counter_config {
__u32 type;
__u64 event;
__u64 umask;
+ __u64 config;
struct perf_event_attr pe;
struct membw_read_format return_value;
int fd;
@@ -39,9 +42,11 @@ struct membw_read_config {
const char *event;
double scale;
int (*num_of)(void);
+ const char *mbm_path;
};
static int num_of_imcs(void);
+static int num_of_hisi_ddrc(void);
static struct membw_read_config membw_read_configs[] = {
{
@@ -50,6 +55,15 @@ static struct membw_read_config membw_read_configs[] = {
.event = "events/cas_count_read",
.scale = 64.0 / MB,
.num_of = num_of_imcs,
+ .mbm_path = CON_MBM_LOCAL_BYTES_PATH
+ },
+ {
+ .vendor_id = ARCH_HISILICON,
+ .name = "hisi_sccl%d_ddrc%d_%d",
+ .event = "events/flux_rd",
+ .scale = 32.0 / MB,
+ .num_of = num_of_hisi_ddrc,
+ .mbm_path = CON_MBM_TOTAL_BYTES_PATH
},
{
.vendor_id = NULL
@@ -71,6 +85,7 @@ static void read_mem_bw_initialize_perf_event_attr(struct imc_counter_config *im
imc_counters_config->pe.inherit = 1;
imc_counters_config->pe.exclude_guest = 0;
imc_counters_config->pe.config =
+ imc_counters_config->config ? :
imc_counters_config->umask << 8 |
imc_counters_config->event;
imc_counters_config->pe.sample_type = PERF_SAMPLE_IDENTIFIER;
@@ -114,6 +129,8 @@ static void get_read_event_and_umask(char *cas_count_cfg, struct imc_counter_con
imc_counters_config->event = strtol(token[i + 1], NULL, 16);
if (strcmp(token[i], "umask") == 0)
imc_counters_config->umask = strtol(token[i + 1], NULL, 16);
+ if (strcmp(token[i], "config") == 0)
+ imc_counters_config->config = strtol(token[i + 1], NULL, 16);
}
}
@@ -248,6 +265,49 @@ static int num_of_imcs(void)
return count;
}
+static int num_of_hisi_ddrc(void)
+{
+ char hisi_ddrc_dir[512], *temp;
+ unsigned int count = 0;
+ struct dirent *ep;
+ int ret;
+ DIR *dp;
+ struct imc_counter_config *imc_counters_config;
+
+ dp = opendir(DYN_PMU_PATH);
+ if (dp) {
+ while ((ep = readdir(dp))) {
+ if (!strstr(ep->d_name, "hisi") || !strstr(ep->d_name, "ddrc"))
+ continue;
+
+ imc_counters_config = malloc(sizeof(struct imc_counter_config));
+ sprintf(hisi_ddrc_dir, "%s/%s/", DYN_PMU_PATH,
+ ep->d_name);
+ ret = read_from_imc_dir(hisi_ddrc_dir, imc_counters_config);
+ if (ret) {
+ free(imc_counters_config);
+ closedir(dp);
+
+ return ret;
+ }
+ list_add(&imc_counters_config->imc_list, &imc_counters_configs);
+ count++;
+ }
+ closedir(dp);
+ if (count == 0) {
+ ksft_print_msg("Unable to find PMU counters\n");
+
+ return -1;
+ }
+ } else {
+ ksft_perror("Unable to open PMU directory");
+
+ return -1;
+ }
+
+ return count;
+}
+
int initialize_read_mem_bw_imc(void)
{
struct imc_counter_config *imc_counters_config;
@@ -382,7 +442,7 @@ static int get_read_mem_bw_imc(float *bw_imc)
void initialize_mem_bw_resctrl(const struct resctrl_val_param *param,
int domain_id)
{
- sprintf(mbm_total_path, CON_MBM_LOCAL_BYTES_PATH, RESCTRL_PATH,
+ sprintf(mbm_total_path, current_config->mbm_path, RESCTRL_PATH,
param->ctrlgrp, domain_id);
}
@@ -579,7 +639,10 @@ int measure_read_mem_bw(const struct user_params *uparams,
perf_close_imc_read_mem_bw();
fclose(mem_bw_fp);
- bw_resc = (bw_resc_end - bw_resc_start) / MB;
+ if (get_vendor() == ARCH_HISILICON)
+ bw_resc = bw_resc_end;
+ else
+ bw_resc = (bw_resc_end - bw_resc_start) / MB;
return print_results_bw(param->filename, bm_pid, bw_imc, bw_resc);
diff --git a/tools/testing/selftests/resctrl/resctrlfs.c b/tools/testing/selftests/resctrl/resctrlfs.c
index b9c1bfb6cc02..01b775cfe849 100644
--- a/tools/testing/selftests/resctrl/resctrlfs.c
+++ b/tools/testing/selftests/resctrl/resctrlfs.c
@@ -139,6 +139,26 @@ int get_domain_id(const char *resource, int cpu_no, int *domain_id)
if (cache_num < 0)
return cache_num;
+ /* On HiSilicon's platform, the "MB" resource domain is associated with the NUMA Node. */
+ if (get_vendor() == ARCH_HISILICON && !strncmp(resource, "MB", sizeof("MB"))) {
+ struct dirent *ep;
+ DIR *dp;
+
+ sprintf(phys_pkg_path, "%s%d/", PHYS_ID_PATH, cpu_no);
+ dp = opendir(phys_pkg_path);
+ if (dp) {
+ while ((ep = readdir(dp))) {
+ if (!strstr(ep->d_name, "node"))
+ continue;
+ if (sscanf(ep->d_name, "node%d\n", domain_id) == 1)
+ return 0;
+ }
+ closedir(dp);
+ }
+ ksft_perror("Could not get domain ID");
+ return -1;
+ }
+
sprintf(phys_pkg_path, "%s%d/cache/index%d/id", PHYS_ID_PATH, cpu_no, cache_num);
fp = fopen(phys_pkg_path, "r");
--
2.33.0