2024-05-31 13:12:37

by Ilpo Järvinen

[permalink] [raw]
Subject: [PATCH v5 00/16] selftests/resctrl: resctrl_val() related cleanups & improvements

Hi all,

This series does a number of cleanups into resctrl_val() and
generalizes it by removing test name specific handling from the
function.

Hopefully these reach also Shuah successfully as I've recently seen
rejects for mail from @linux.intel.com to gmail addresses.

v5:
- Open mem bw file only once and use rewind().
- Add \n to mem bw file read to allow reading fresh values from the file.
- Return 0 if create_grp() is given NULL grp_name (matches the original
behavior). Mention this in function's kerneldoc.
- Cast pid_t to int before printing with %d.
- Caps/typo fixes to kerneldoc and commit messages.
- Use imperative tone in commit messages and improve them based on points
that came up during review.

v4:
- Merged close fix into IMC READ+WRITE rework patch
- Add loop to reset imc_counters_config fds to -1 to be able know which
need closing
- Introduce perf_close_imc_mem_bw() to close fds
- Open resctrl mem bw file (twice) beforehand to avoid opening it during
the test
- Remove MBM .mongrp setup
- Remove mongrp from CMT test

v3:
- Rename init functions to <testname>_init()
- Replace for loops with READ+WRITE statements for clarity
- Don't drop Return: entry from perf_open_imc_mem_bw() func comment
- New patch: Fix closing of IMC fds in case of error
- New patch: Make "bandwidth" consistent in comments & prints
- New patch: Simplify mem bandwidth file code
- Remove wrong comment
- Changed grp_name check to return -1 on fail (internal sanity check)

v2:
- Resolved conflicts with kselftest/next
- Spaces -> tabs correction

Ilpo Järvinen (16):
selftests/resctrl: Fix closing IMC fds on error and open-code R+W
instead of loops
selftests/resctrl: Calculate resctrl FS derived mem bw over sleep(1)
only
selftests/resctrl: Make "bandwidth" consistent in comments & prints
selftests/resctrl: Consolidate get_domain_id() into resctrl_val()
selftests/resctrl: Use correct type for pids
selftests/resctrl: Cleanup bm_pid and ppid usage & limit scope
selftests/resctrl: Rename measure_vals() to measure_mem_bw_vals() &
document
selftests/resctrl: Simplify mem bandwidth file code for MBA & MBM
tests
selftests/resctrl: Add ->measure() callback to resctrl_val_param
selftests/resctrl: Add ->init() callback into resctrl_val_param
selftests/resctrl: Simplify bandwidth report type handling
selftests/resctrl: Make some strings passed to resctrlfs functions
const
selftests/resctrl: Convert ctrlgrp & mongrp to pointers
selftests/resctrl: Remove mongrp from MBA test
selftests/resctrl: Remove mongrp from CMT test
selftests/resctrl: Remove test name comparing from
write_bm_pid_to_resctrl()

tools/testing/selftests/resctrl/cache.c | 10 +-
tools/testing/selftests/resctrl/cat_test.c | 5 +-
tools/testing/selftests/resctrl/cmt_test.c | 22 +-
tools/testing/selftests/resctrl/mba_test.c | 26 +-
tools/testing/selftests/resctrl/mbm_test.c | 26 +-
tools/testing/selftests/resctrl/resctrl.h | 49 ++-
tools/testing/selftests/resctrl/resctrl_val.c | 364 ++++++++----------
tools/testing/selftests/resctrl/resctrlfs.c | 67 ++--
8 files changed, 290 insertions(+), 279 deletions(-)

--
2.39.2



2024-05-31 13:13:52

by Ilpo Järvinen

[permalink] [raw]
Subject: [PATCH v5 05/16] selftests/resctrl: Use correct type for pids

A few functions receive PIDs through int arguments. PIDs variables
should be of type pid_t, not int.

Convert pid arguments from int to pid_t.

Before printing PID, match the type to %d by casting to int which is
enough for Linux (standard would allow using a longer integer type but
generalizing for that would complicate the code unnecessarily, the
selftest code does not need to be portable).

Signed-off-by: Ilpo Järvinen <[email protected]>
---

v5:
- Cast to int before printing to match with %d.
---
tools/testing/selftests/resctrl/cache.c | 10 +++++-----
tools/testing/selftests/resctrl/resctrl.h | 4 ++--
tools/testing/selftests/resctrl/resctrl_val.c | 8 ++++----
tools/testing/selftests/resctrl/resctrlfs.c | 2 +-
4 files changed, 12 insertions(+), 12 deletions(-)

diff --git a/tools/testing/selftests/resctrl/cache.c b/tools/testing/selftests/resctrl/cache.c
index 1b339d6bbff1..1ff1104e6575 100644
--- a/tools/testing/selftests/resctrl/cache.c
+++ b/tools/testing/selftests/resctrl/cache.c
@@ -101,12 +101,12 @@ static int get_llc_occu_resctrl(unsigned long *llc_occupancy)
*
* Return: 0 on success, < 0 on error.
*/
-static int print_results_cache(const char *filename, int bm_pid, __u64 llc_value)
+static int print_results_cache(const char *filename, pid_t bm_pid, __u64 llc_value)
{
FILE *fp;

if (strcmp(filename, "stdio") == 0 || strcmp(filename, "stderr") == 0) {
- printf("Pid: %d \t LLC_value: %llu\n", bm_pid, llc_value);
+ printf("Pid: %d \t LLC_value: %llu\n", (int)bm_pid, llc_value);
} else {
fp = fopen(filename, "a");
if (!fp) {
@@ -114,7 +114,7 @@ static int print_results_cache(const char *filename, int bm_pid, __u64 llc_value

return -1;
}
- fprintf(fp, "Pid: %d \t llc_value: %llu\n", bm_pid, llc_value);
+ fprintf(fp, "Pid: %d \t llc_value: %llu\n", (int)bm_pid, llc_value);
fclose(fp);
}

@@ -133,7 +133,7 @@ static int print_results_cache(const char *filename, int bm_pid, __u64 llc_value
* Return: =0 on success. <0 on failure.
*/
int perf_event_measure(int pe_fd, struct perf_event_read *pe_read,
- const char *filename, int bm_pid)
+ const char *filename, pid_t bm_pid)
{
int ret;

@@ -161,7 +161,7 @@ int perf_event_measure(int pe_fd, struct perf_event_read *pe_read,
*
* Return: =0 on success. <0 on failure.
*/
-int measure_llc_resctrl(const char *filename, int bm_pid)
+int measure_llc_resctrl(const char *filename, pid_t bm_pid)
{
unsigned long llc_occu_resc = 0;
int ret;
diff --git a/tools/testing/selftests/resctrl/resctrl.h b/tools/testing/selftests/resctrl/resctrl.h
index 00d51fa7531c..e6f221236c79 100644
--- a/tools/testing/selftests/resctrl/resctrl.h
+++ b/tools/testing/selftests/resctrl/resctrl.h
@@ -174,8 +174,8 @@ void perf_event_initialize_read_format(struct perf_event_read *pe_read);
int perf_open(struct perf_event_attr *pea, pid_t pid, int cpu_no);
int perf_event_reset_enable(int pe_fd);
int perf_event_measure(int pe_fd, struct perf_event_read *pe_read,
- const char *filename, int bm_pid);
-int measure_llc_resctrl(const char *filename, int bm_pid);
+ const char *filename, pid_t bm_pid);
+int measure_llc_resctrl(const char *filename, pid_t bm_pid);
void show_cache_info(int no_of_bits, __u64 avg_llc_val, size_t cache_span, bool lines);

/*
diff --git a/tools/testing/selftests/resctrl/resctrl_val.c b/tools/testing/selftests/resctrl/resctrl_val.c
index e1ae59063c51..d6f6db77d480 100644
--- a/tools/testing/selftests/resctrl/resctrl_val.c
+++ b/tools/testing/selftests/resctrl/resctrl_val.c
@@ -572,14 +572,14 @@ void signal_handler_unregister(void)
*
* Return: 0 on success, < 0 on error.
*/
-static int print_results_bw(char *filename, int bm_pid, float bw_imc,
+static int print_results_bw(char *filename, pid_t bm_pid, float bw_imc,
unsigned long bw_resc)
{
unsigned long diff = fabs(bw_imc - bw_resc);
FILE *fp;

if (strcmp(filename, "stdio") == 0 || strcmp(filename, "stderr") == 0) {
- printf("Pid: %d \t Mem_BW_iMC: %f \t ", bm_pid, bw_imc);
+ printf("Pid: %d \t Mem_BW_iMC: %f \t ", (int)bm_pid, bw_imc);
printf("Mem_BW_resc: %lu \t Difference: %lu\n", bw_resc, diff);
} else {
fp = fopen(filename, "a");
@@ -589,7 +589,7 @@ static int print_results_bw(char *filename, int bm_pid, float bw_imc,
return -1;
}
if (fprintf(fp, "Pid: %d \t Mem_BW_iMC: %f \t Mem_BW_resc: %lu \t Difference: %lu\n",
- bm_pid, bw_imc, bw_resc, diff) <= 0) {
+ (int)bm_pid, bw_imc, bw_resc, diff) <= 0) {
ksft_print_msg("Could not log results\n");
fclose(fp);

@@ -832,7 +832,7 @@ int resctrl_val(const struct resctrl_test *test,
PARENT_EXIT();
}

- ksft_print_msg("Benchmark PID: %d\n", bm_pid);
+ ksft_print_msg("Benchmark PID: %d\n", (int)bm_pid);

/*
* The cast removes constness but nothing mutates benchmark_cmd within
diff --git a/tools/testing/selftests/resctrl/resctrlfs.c b/tools/testing/selftests/resctrl/resctrlfs.c
index 9b86f826a40c..917d677adbba 100644
--- a/tools/testing/selftests/resctrl/resctrlfs.c
+++ b/tools/testing/selftests/resctrl/resctrlfs.c
@@ -508,7 +508,7 @@ static int write_pid_to_tasks(char *tasks, pid_t pid)

return -1;
}
- if (fprintf(fp, "%d\n", pid) < 0) {
+ if (fprintf(fp, "%d\n", (int)pid) < 0) {
ksft_print_msg("Failed to write pid to tasks file\n");
fclose(fp);

--
2.39.2


2024-05-31 13:15:16

by Ilpo Järvinen

[permalink] [raw]
Subject: [PATCH v5 11/16] selftests/resctrl: Simplify bandwidth report type handling

bw_report is only needed for selecting the correct value from the
values IMC measured. It is a member in the resctrl_val_param struct and
is always set to "reads". The value is then checked in resctrl_val()
using validate_bw_report_request() that besides validating the input,
assumes it can mutate the string which is questionable programming
practice.

Simplify handling bw_report:

- Convert validate_bw_report_request() into get_bw_report_type() that
inputs and returns const char *. Use NULL to indicate error.

- Validate the report types inside measure_mem_bw(), not in
resctrl_val().

- Pass bw_report to measure_mem_bw() from ->measure() hook because
resctrl_val() no longer needs bw_report for anything.

Signed-off-by: Ilpo Järvinen <[email protected]>
Reviewed-by: Reinette Chatre <[email protected]>
---
v5:
- Use imperative tone in commit message
v2:
- Rebased on top of next to resolve conflict in resctrl.h
---
tools/testing/selftests/resctrl/mba_test.c | 3 +--
tools/testing/selftests/resctrl/mbm_test.c | 3 +--
tools/testing/selftests/resctrl/resctrl.h | 7 +++----
tools/testing/selftests/resctrl/resctrl_val.c | 19 +++++++++----------
tools/testing/selftests/resctrl/resctrlfs.c | 13 ++++++-------
5 files changed, 20 insertions(+), 25 deletions(-)

diff --git a/tools/testing/selftests/resctrl/mba_test.c b/tools/testing/selftests/resctrl/mba_test.c
index 0a95c42f1616..9c9a4f22e529 100644
--- a/tools/testing/selftests/resctrl/mba_test.c
+++ b/tools/testing/selftests/resctrl/mba_test.c
@@ -67,7 +67,7 @@ static int mba_setup(const struct resctrl_test *test,
static int mba_measure(const struct user_params *uparams,
struct resctrl_val_param *param, pid_t bm_pid)
{
- return measure_mem_bw(uparams, param, bm_pid);
+ return measure_mem_bw(uparams, param, bm_pid, "reads");
}

static bool show_mba_info(unsigned long *bw_imc, unsigned long *bw_resc)
@@ -168,7 +168,6 @@ static int mba_run_test(const struct resctrl_test *test, const struct user_param
.ctrlgrp = "c1",
.mongrp = "m1",
.filename = RESULT_FILE_NAME,
- .bw_report = "reads",
.init = mba_init,
.setup = mba_setup,
.measure = mba_measure,
diff --git a/tools/testing/selftests/resctrl/mbm_test.c b/tools/testing/selftests/resctrl/mbm_test.c
index 00e60b01188a..27b936fe60bc 100644
--- a/tools/testing/selftests/resctrl/mbm_test.c
+++ b/tools/testing/selftests/resctrl/mbm_test.c
@@ -121,7 +121,7 @@ static int mbm_setup(const struct resctrl_test *test,
static int mbm_measure(const struct user_params *uparams,
struct resctrl_val_param *param, pid_t bm_pid)
{
- return measure_mem_bw(uparams, param, bm_pid);
+ return measure_mem_bw(uparams, param, bm_pid, "reads");
}

static void mbm_test_cleanup(void)
@@ -135,7 +135,6 @@ static int mbm_run_test(const struct resctrl_test *test, const struct user_param
.resctrl_val = MBM_STR,
.ctrlgrp = "c1",
.filename = RESULT_FILE_NAME,
- .bw_report = "reads",
.init = mbm_init,
.setup = mbm_setup,
.measure = mbm_measure,
diff --git a/tools/testing/selftests/resctrl/resctrl.h b/tools/testing/selftests/resctrl/resctrl.h
index d3fbb957309d..4446a0e493ef 100644
--- a/tools/testing/selftests/resctrl/resctrl.h
+++ b/tools/testing/selftests/resctrl/resctrl.h
@@ -85,7 +85,6 @@ struct resctrl_test {
* @ctrlgrp: Name of the control monitor group (con_mon grp)
* @mongrp: Name of the monitor group (mon grp)
* @filename: Name of file to which the o/p should be written
- * @bw_report: Bandwidth report type (reads vs writes)
* @init: Callback function to initialize test environment
* @setup: Callback function to setup per test run environment
* @measure: Callback that performs the measurement (a single test)
@@ -95,7 +94,6 @@ struct resctrl_val_param {
char ctrlgrp[64];
char mongrp[64];
char filename[64];
- char *bw_report;
unsigned long mask;
int num_of_runs;
int (*init)(const struct resctrl_val_param *param,
@@ -135,7 +133,7 @@ int filter_dmesg(void);
int get_domain_id(const char *resource, int cpu_no, int *domain_id);
int mount_resctrlfs(void);
int umount_resctrlfs(void);
-int validate_bw_report_request(char *bw_report);
+const char *get_bw_report_type(const char *bw_report);
bool resctrl_resource_exists(const char *resource);
bool resctrl_mon_feature_exists(const char *resource, const char *feature);
bool resource_info_file_exists(const char *resource, const char *file);
@@ -154,7 +152,8 @@ void fill_cache_read(unsigned char *buf, size_t buf_size, bool once);
int run_fill_buf(size_t buf_size, int memflush, int op, bool once);
int initialize_mem_bw_imc(void);
int measure_mem_bw(const struct user_params *uparams,
- struct resctrl_val_param *param, pid_t bm_pid);
+ struct resctrl_val_param *param, pid_t bm_pid,
+ const char *bw_report);
void initialize_mem_bw_resctrl(const struct resctrl_val_param *param,
int domain_id);
int resctrl_val(const struct resctrl_test *test,
diff --git a/tools/testing/selftests/resctrl/resctrl_val.c b/tools/testing/selftests/resctrl/resctrl_val.c
index 164f57454cb0..26350fccc1c1 100644
--- a/tools/testing/selftests/resctrl/resctrl_val.c
+++ b/tools/testing/selftests/resctrl/resctrl_val.c
@@ -349,7 +349,7 @@ static void do_imc_mem_bw_test(void)
*
* Return: = 0 on success. < 0 on failure.
*/
-static int get_mem_bw_imc(char *bw_report, float *bw_imc)
+static int get_mem_bw_imc(const char *bw_report, float *bw_imc)
{
float reads, writes, of_mul_read, of_mul_write;
int imc;
@@ -562,15 +562,21 @@ static int print_results_bw(char *filename, pid_t bm_pid, float bw_imc,
* @uparams: User supplied parameters
* @param: Parameters passed to resctrl_val()
* @bm_pid: PID that runs the benchmark
+ * @bw_report: Bandwidth report type (reads, writes)
*/
int measure_mem_bw(const struct user_params *uparams,
- struct resctrl_val_param *param, pid_t bm_pid)
+ struct resctrl_val_param *param, pid_t bm_pid,
+ const char *bw_report)
{
unsigned long bw_resc, bw_resc_start, bw_resc_end;
FILE *mem_bw_fp;
float bw_imc;
int ret;

+ bw_report = get_bw_report_type(bw_report);
+ if (!bw_report)
+ return -1;
+
mem_bw_fp = open_mem_bw_resctrl(mbm_total_path);
if (!mem_bw_fp)
return -1;
@@ -598,7 +604,7 @@ int measure_mem_bw(const struct user_params *uparams,
if (ret < 0)
goto close_fp;

- ret = get_mem_bw_imc(param->bw_report, &bw_imc);
+ ret = get_mem_bw_imc(bw_report, &bw_imc);
if (ret < 0)
goto close_fp;

@@ -699,13 +705,6 @@ int resctrl_val(const struct resctrl_test *test,
return ret;
}

- if (!strncmp(resctrl_val, MBA_STR, sizeof(MBA_STR)) ||
- !strncmp(resctrl_val, MBM_STR, sizeof(MBM_STR))) {
- ret = validate_bw_report_request(param->bw_report);
- if (ret)
- return ret;
- }
-
/*
* If benchmark wasn't successfully started by child, then child should
* kill parent, so save parent's pid
diff --git a/tools/testing/selftests/resctrl/resctrlfs.c b/tools/testing/selftests/resctrl/resctrlfs.c
index 917d677adbba..9e4cda154d66 100644
--- a/tools/testing/selftests/resctrl/resctrlfs.c
+++ b/tools/testing/selftests/resctrl/resctrlfs.c
@@ -837,22 +837,21 @@ int filter_dmesg(void)
return 0;
}

-int validate_bw_report_request(char *bw_report)
+const char *get_bw_report_type(const char *bw_report)
{
if (strcmp(bw_report, "reads") == 0)
- return 0;
+ return bw_report;
if (strcmp(bw_report, "writes") == 0)
- return 0;
+ return bw_report;
if (strcmp(bw_report, "nt-writes") == 0) {
- strcpy(bw_report, "writes");
- return 0;
+ return "writes";
}
if (strcmp(bw_report, "total") == 0)
- return 0;
+ return bw_report;

fprintf(stderr, "Requested iMC bandwidth report type unavailable\n");

- return -1;
+ return NULL;
}

int perf_event_open(struct perf_event_attr *hw_event, pid_t pid, int cpu,
--
2.39.2


2024-05-31 13:16:44

by Ilpo Järvinen

[permalink] [raw]
Subject: [PATCH v5 15/16] selftests/resctrl: Remove mongrp from CMT test

The CMT selftest instantiates a monitor group to read LLC occupancy.
Since the test also creates a control group, it is unnecessary to
create another one for monitoring because control groups already
provide monitoring too.

Remove the unnecessary monitor group from the CMT selftest.

Suggested-by: Reinette Chatre <[email protected]>
Signed-off-by: Ilpo Järvinen <[email protected]>
Reviewed-by: Reinette Chatre <[email protected]>
--

v4:
- New patch
---
tools/testing/selftests/resctrl/cmt_test.c | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/tools/testing/selftests/resctrl/cmt_test.c b/tools/testing/selftests/resctrl/cmt_test.c
index 238f514ba7e6..b63fa1e93307 100644
--- a/tools/testing/selftests/resctrl/cmt_test.c
+++ b/tools/testing/selftests/resctrl/cmt_test.c
@@ -17,12 +17,12 @@
#define MAX_DIFF_PERCENT 15

#define CON_MON_LCC_OCCUP_PATH \
- "%s/%s/mon_groups/%s/mon_data/mon_L3_%02d/llc_occupancy"
+ "%s/%s/mon_data/mon_L3_%02d/llc_occupancy"

static int cmt_init(const struct resctrl_val_param *param, int domain_id)
{
sprintf(llc_occup_path, CON_MON_LCC_OCCUP_PATH, RESCTRL_PATH,
- param->ctrlgrp, param->mongrp, domain_id);
+ param->ctrlgrp, domain_id);

return 0;
}
@@ -146,7 +146,6 @@ static int cmt_run_test(const struct resctrl_test *test, const struct user_param
struct resctrl_val_param param = {
.resctrl_val = CMT_STR,
.ctrlgrp = "c1",
- .mongrp = "m1",
.filename = RESULT_FILE_NAME,
.mask = ~(long_mask << n) & long_mask,
.num_of_runs = 0,
--
2.39.2


2024-05-31 14:18:45

by Ilpo Järvinen

[permalink] [raw]
Subject: [PATCH v5 01/16] selftests/resctrl: Fix closing IMC fds on error and open-code R+W instead of loops

The imc perf fd close() calls are missing from all error paths. In
addition, get_mem_bw_imc() handles fds in a for loop but close() is
based on two fixed indexes READ and WRITE.

Open code inner for loops to READ+WRITE entries for clarity and add a
function to close() IMC fds properly in all cases.

Fixes: 7f4d257e3a2a ("selftests/resctrl: Add callback to start a benchmark")
Suggested-by: Reinette Chatre <[email protected]>
Signed-off-by: Ilpo Järvinen <[email protected]>
Reviewed-by: Reinette Chatre <[email protected]>
---

v4:
- Merge with the fix close patch
- Add loop to reset imc_counters_config fds to -1 to be able know which
need closing
- Introduce perf_close_imc_mem_bw() to close fds
v3:
- Rework entirely, use open coding instead of for loops for clarity
---
tools/testing/selftests/resctrl/resctrl_val.c | 54 ++++++++++++-------
1 file changed, 36 insertions(+), 18 deletions(-)

diff --git a/tools/testing/selftests/resctrl/resctrl_val.c b/tools/testing/selftests/resctrl/resctrl_val.c
index 445f306d4c2f..f55f5989de72 100644
--- a/tools/testing/selftests/resctrl/resctrl_val.c
+++ b/tools/testing/selftests/resctrl/resctrl_val.c
@@ -293,6 +293,18 @@ static int initialize_mem_bw_imc(void)
return 0;
}

+static void perf_close_imc_mem_bw(void)
+{
+ int mc;
+
+ for (mc = 0; mc < imcs; mc++) {
+ if (imc_counters_config[mc][READ].fd != -1)
+ close(imc_counters_config[mc][READ].fd);
+ if (imc_counters_config[mc][WRITE].fd != -1)
+ close(imc_counters_config[mc][WRITE].fd);
+ }
+}
+
/*
* get_mem_bw_imc: Memory band width as reported by iMC counters
* @cpu_no: CPU number that the benchmark PID is binded to
@@ -306,26 +318,33 @@ static int initialize_mem_bw_imc(void)
static int get_mem_bw_imc(int cpu_no, char *bw_report, float *bw_imc)
{
float reads, writes, of_mul_read, of_mul_write;
- int imc, j, ret;
+ int imc, ret;
+
+ for (imc = 0; imc < imcs; imc++) {
+ imc_counters_config[imc][READ].fd = -1;
+ imc_counters_config[imc][WRITE].fd = -1;
+ }

/* Start all iMC counters to log values (both read and write) */
reads = 0, writes = 0, of_mul_read = 1, of_mul_write = 1;
for (imc = 0; imc < imcs; imc++) {
- for (j = 0; j < 2; j++) {
- ret = open_perf_event(imc, cpu_no, j);
- if (ret)
- return -1;
- }
- for (j = 0; j < 2; j++)
- membw_ioctl_perf_event_ioc_reset_enable(imc, j);
+ ret = open_perf_event(imc, cpu_no, READ);
+ if (ret)
+ goto close_fds;
+ ret = open_perf_event(imc, cpu_no, WRITE);
+ if (ret)
+ goto close_fds;
+
+ membw_ioctl_perf_event_ioc_reset_enable(imc, READ);
+ membw_ioctl_perf_event_ioc_reset_enable(imc, WRITE);
}

sleep(1);

/* Stop counters after a second to get results (both read and write) */
for (imc = 0; imc < imcs; imc++) {
- for (j = 0; j < 2; j++)
- membw_ioctl_perf_event_ioc_disable(imc, j);
+ membw_ioctl_perf_event_ioc_disable(imc, READ);
+ membw_ioctl_perf_event_ioc_disable(imc, WRITE);
}

/*
@@ -341,15 +360,13 @@ static int get_mem_bw_imc(int cpu_no, char *bw_report, float *bw_imc)
if (read(r->fd, &r->return_value,
sizeof(struct membw_read_format)) == -1) {
ksft_perror("Couldn't get read b/w through iMC");
-
- return -1;
+ goto close_fds;
}

if (read(w->fd, &w->return_value,
sizeof(struct membw_read_format)) == -1) {
ksft_perror("Couldn't get write bw through iMC");
-
- return -1;
+ goto close_fds;
}

__u64 r_time_enabled = r->return_value.time_enabled;
@@ -369,10 +386,7 @@ static int get_mem_bw_imc(int cpu_no, char *bw_report, float *bw_imc)
writes += w->return_value.value * of_mul_write * SCALE;
}

- for (imc = 0; imc < imcs; imc++) {
- close(imc_counters_config[imc][READ].fd);
- close(imc_counters_config[imc][WRITE].fd);
- }
+ perf_close_imc_mem_bw();

if (strcmp(bw_report, "reads") == 0) {
*bw_imc = reads;
@@ -386,6 +400,10 @@ static int get_mem_bw_imc(int cpu_no, char *bw_report, float *bw_imc)

*bw_imc = reads + writes;
return 0;
+
+close_fds:
+ perf_close_imc_mem_bw();
+ return -1;
}

void set_mbm_path(const char *ctrlgrp, const char *mongrp, int domain_id)
--
2.39.2


2024-05-31 14:19:03

by Ilpo Järvinen

[permalink] [raw]
Subject: [PATCH v5 03/16] selftests/resctrl: Make "bandwidth" consistent in comments & prints

Resctrl selftests refer to "bandwidth" currently in two other forms in
the code ("B/W" and "band width").

Use "bandwidth" consistently everywhere. While at it, fix also one
"over flow" -> "overflow" on a line that is touched by the change.

Suggested-by: Reinette Chatre <[email protected]>
Signed-off-by: Ilpo Järvinen <[email protected]>
Reviewed-by: Reinette Chatre <[email protected]>
---

v3:
- New patch
---
tools/testing/selftests/resctrl/resctrl_val.c | 14 +++++++-------
tools/testing/selftests/resctrl/resctrlfs.c | 2 +-
2 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/tools/testing/selftests/resctrl/resctrl_val.c b/tools/testing/selftests/resctrl/resctrl_val.c
index 6231275a6e6c..cb646168179e 100644
--- a/tools/testing/selftests/resctrl/resctrl_val.c
+++ b/tools/testing/selftests/resctrl/resctrl_val.c
@@ -361,11 +361,11 @@ static void do_imc_mem_bw_test(void)
}

/*
- * get_mem_bw_imc - Memory band width as reported by iMC counters
+ * get_mem_bw_imc - Memory bandwidth as reported by iMC counters
* @bw_report: Bandwidth report type (reads, writes)
*
- * Memory B/W utilized by a process on a socket can be calculated using
- * iMC counters. Perf events are used to read these counters.
+ * Memory bandwidth utilized by a process on a socket can be calculated
+ * using iMC counters. Perf events are used to read these counters.
*
* Return: = 0 on success. < 0 on failure.
*/
@@ -379,7 +379,7 @@ static int get_mem_bw_imc(char *bw_report, float *bw_imc)

/*
* Get results which are stored in struct type imc_counter_config
- * Take over flow into consideration before calculating total b/w
+ * Take overflow into consideration before calculating total bandwidth.
*/
for (imc = 0; imc < imcs; imc++) {
struct imc_counter_config *r =
@@ -389,13 +389,13 @@ static int get_mem_bw_imc(char *bw_report, float *bw_imc)

if (read(r->fd, &r->return_value,
sizeof(struct membw_read_format)) == -1) {
- ksft_perror("Couldn't get read b/w through iMC");
+ ksft_perror("Couldn't get read bandwidth through iMC");
goto close_fds;
}

if (read(w->fd, &w->return_value,
sizeof(struct membw_read_format)) == -1) {
- ksft_perror("Couldn't get write bw through iMC");
+ ksft_perror("Couldn't get write bandwidth through iMC");
goto close_fds;
}

@@ -498,7 +498,7 @@ static FILE *open_mem_bw_resctrl(const char *mbm_bw_file)

fp = fopen(mbm_bw_file, "r");
if (!fp)
- ksft_perror("Failed to open total bw file");
+ ksft_perror("Failed to open total memory bandwidth file");

return fp;
}
diff --git a/tools/testing/selftests/resctrl/resctrlfs.c b/tools/testing/selftests/resctrl/resctrlfs.c
index 1cade75176eb..9b86f826a40c 100644
--- a/tools/testing/selftests/resctrl/resctrlfs.c
+++ b/tools/testing/selftests/resctrl/resctrlfs.c
@@ -850,7 +850,7 @@ int validate_bw_report_request(char *bw_report)
if (strcmp(bw_report, "total") == 0)
return 0;

- fprintf(stderr, "Requested iMC B/W report type unavailable\n");
+ fprintf(stderr, "Requested iMC bandwidth report type unavailable\n");

return -1;
}
--
2.39.2


2024-05-31 14:56:02

by Ilpo Järvinen

[permalink] [raw]
Subject: [PATCH v5 16/16] selftests/resctrl: Remove test name comparing from write_bm_pid_to_resctrl()

write_bm_pid_to_resctrl() uses resctrl_val to check test name which is
not a good interface generic resctrl FS functions should provide.

Tests define mongrp when needed. Remove the test name check in
write_bm_pid_to_resctrl() to only rely on the mongrp parameter being
non-NULL.

Remove write_bm_pid_to_resctrl() resctrl_val parameter and resctrl_val
member from the struct resctrl_val_param that are not used anymore.
Similarly, remove the test name constants that are no longer used.

Signed-off-by: Ilpo Järvinen <[email protected]>
---
tools/testing/selftests/resctrl/cat_test.c | 5 +--
tools/testing/selftests/resctrl/cmt_test.c | 1 -
tools/testing/selftests/resctrl/mba_test.c | 1 -
tools/testing/selftests/resctrl/mbm_test.c | 1 -
tools/testing/selftests/resctrl/resctrl.h | 10 +-----
tools/testing/selftests/resctrl/resctrl_val.c | 4 +--
tools/testing/selftests/resctrl/resctrlfs.c | 33 ++++++++-----------
7 files changed, 17 insertions(+), 38 deletions(-)

diff --git a/tools/testing/selftests/resctrl/cat_test.c b/tools/testing/selftests/resctrl/cat_test.c
index c7686fb6641a..d4dffc934bc3 100644
--- a/tools/testing/selftests/resctrl/cat_test.c
+++ b/tools/testing/selftests/resctrl/cat_test.c
@@ -158,7 +158,6 @@ static int cat_test(const struct resctrl_test *test,
struct resctrl_val_param *param,
size_t span, unsigned long current_mask)
{
- char *resctrl_val = param->resctrl_val;
struct perf_event_read pe_read;
struct perf_event_attr pea;
cpu_set_t old_affinity;
@@ -178,8 +177,7 @@ static int cat_test(const struct resctrl_test *test,
return ret;

/* Write benchmark to specified con_mon grp, mon_grp in resctrl FS*/
- ret = write_bm_pid_to_resctrl(bm_pid, param->ctrlgrp, param->mongrp,
- resctrl_val);
+ ret = write_bm_pid_to_resctrl(bm_pid, param->ctrlgrp, param->mongrp);
if (ret)
goto reset_affinity;

@@ -272,7 +270,6 @@ static int cat_run_test(const struct resctrl_test *test, const struct user_param
start_mask = create_bit_mask(start, n);

struct resctrl_val_param param = {
- .resctrl_val = CAT_STR,
.ctrlgrp = "c1",
.filename = RESULT_FILE_NAME,
.num_of_runs = 0,
diff --git a/tools/testing/selftests/resctrl/cmt_test.c b/tools/testing/selftests/resctrl/cmt_test.c
index b63fa1e93307..d1c272743eb2 100644
--- a/tools/testing/selftests/resctrl/cmt_test.c
+++ b/tools/testing/selftests/resctrl/cmt_test.c
@@ -144,7 +144,6 @@ static int cmt_run_test(const struct resctrl_test *test, const struct user_param
}

struct resctrl_val_param param = {
- .resctrl_val = CMT_STR,
.ctrlgrp = "c1",
.filename = RESULT_FILE_NAME,
.mask = ~(long_mask << n) & long_mask,
diff --git a/tools/testing/selftests/resctrl/mba_test.c b/tools/testing/selftests/resctrl/mba_test.c
index 5e0b1e794295..1f2a7dc73b62 100644
--- a/tools/testing/selftests/resctrl/mba_test.c
+++ b/tools/testing/selftests/resctrl/mba_test.c
@@ -164,7 +164,6 @@ static void mba_test_cleanup(void)
static int mba_run_test(const struct resctrl_test *test, const struct user_params *uparams)
{
struct resctrl_val_param param = {
- .resctrl_val = MBA_STR,
.ctrlgrp = "c1",
.filename = RESULT_FILE_NAME,
.init = mba_init,
diff --git a/tools/testing/selftests/resctrl/mbm_test.c b/tools/testing/selftests/resctrl/mbm_test.c
index 27b936fe60bc..39aa70374154 100644
--- a/tools/testing/selftests/resctrl/mbm_test.c
+++ b/tools/testing/selftests/resctrl/mbm_test.c
@@ -132,7 +132,6 @@ static void mbm_test_cleanup(void)
static int mbm_run_test(const struct resctrl_test *test, const struct user_params *uparams)
{
struct resctrl_val_param param = {
- .resctrl_val = MBM_STR,
.ctrlgrp = "c1",
.filename = RESULT_FILE_NAME,
.init = mbm_init,
diff --git a/tools/testing/selftests/resctrl/resctrl.h b/tools/testing/selftests/resctrl/resctrl.h
index a999fbc13fd3..2dda56084588 100644
--- a/tools/testing/selftests/resctrl/resctrl.h
+++ b/tools/testing/selftests/resctrl/resctrl.h
@@ -81,7 +81,6 @@ struct resctrl_test {

/*
* resctrl_val_param: resctrl test parameters
- * @resctrl_val: Resctrl feature (Eg: mbm, mba.. etc)
* @ctrlgrp: Name of the control monitor group (con_mon grp)
* @mongrp: Name of the monitor group (mon grp)
* @filename: Name of file to which the o/p should be written
@@ -90,7 +89,6 @@ struct resctrl_test {
* @measure: Callback that performs the measurement (a single test)
*/
struct resctrl_val_param {
- char *resctrl_val;
const char *ctrlgrp;
const char *mongrp;
char filename[64];
@@ -113,11 +111,6 @@ struct perf_event_read {
} values[2];
};

-#define MBM_STR "mbm"
-#define MBA_STR "mba"
-#define CMT_STR "cmt"
-#define CAT_STR "cat"
-
/*
* Memory location that consumes values compiler must not optimize away.
* Volatile ensures writes to this location cannot be optimized away by
@@ -143,8 +136,7 @@ int taskset_benchmark(pid_t bm_pid, int cpu_no, cpu_set_t *old_affinity);
int taskset_restore(pid_t bm_pid, cpu_set_t *old_affinity);
int write_schemata(const char *ctrlgrp, char *schemata, int cpu_no,
const char *resource);
-int write_bm_pid_to_resctrl(pid_t bm_pid, const char *ctrlgrp,
- const char *mongrp, const char *resctrl_val);
+int write_bm_pid_to_resctrl(pid_t bm_pid, const char *ctrlgrp, const char *mongrp);
int perf_event_open(struct perf_event_attr *hw_event, pid_t pid, int cpu,
int group_fd, unsigned long flags);
unsigned char *alloc_buffer(size_t buf_size, int memflush);
diff --git a/tools/testing/selftests/resctrl/resctrl_val.c b/tools/testing/selftests/resctrl/resctrl_val.c
index 26350fccc1c1..35eba2d99d32 100644
--- a/tools/testing/selftests/resctrl/resctrl_val.c
+++ b/tools/testing/selftests/resctrl/resctrl_val.c
@@ -689,7 +689,6 @@ int resctrl_val(const struct resctrl_test *test,
const char * const *benchmark_cmd,
struct resctrl_val_param *param)
{
- char *resctrl_val = param->resctrl_val;
struct sigaction sigact;
int ret = 0, pipefd[2];
char pipe_message = 0;
@@ -780,8 +779,7 @@ int resctrl_val(const struct resctrl_test *test,
goto out;

/* Write benchmark to specified control&monitoring grp in resctrl FS */
- ret = write_bm_pid_to_resctrl(bm_pid, param->ctrlgrp, param->mongrp,
- resctrl_val);
+ ret = write_bm_pid_to_resctrl(bm_pid, param->ctrlgrp, param->mongrp);
if (ret)
goto out;

diff --git a/tools/testing/selftests/resctrl/resctrlfs.c b/tools/testing/selftests/resctrl/resctrlfs.c
index 893041faaf18..891ebfbfbd85 100644
--- a/tools/testing/selftests/resctrl/resctrlfs.c
+++ b/tools/testing/selftests/resctrl/resctrlfs.c
@@ -522,7 +522,6 @@ static int write_pid_to_tasks(char *tasks, pid_t pid)
* @bm_pid: PID that should be written
* @ctrlgrp: Name of the control monitor group (con_mon grp)
* @mongrp: Name of the monitor group (mon grp)
- * @resctrl_val: Resctrl feature (Eg: mbm, mba.. etc)
*
* If a con_mon grp is requested, create it and write pid to it, otherwise
* write pid to root con_mon grp.
@@ -532,8 +531,7 @@ static int write_pid_to_tasks(char *tasks, pid_t pid)
*
* Return: 0 on success, < 0 on error.
*/
-int write_bm_pid_to_resctrl(pid_t bm_pid, const char *ctrlgrp,
- const char *mongrp, const char *resctrl_val)
+int write_bm_pid_to_resctrl(pid_t bm_pid, const char *ctrlgrp, const char *mongrp)
{
char controlgroup[128], monitorgroup[512], monitorgroup_p[256];
char tasks[1024];
@@ -553,22 +551,19 @@ int write_bm_pid_to_resctrl(pid_t bm_pid, const char *ctrlgrp,
if (ret)
goto out;

- /* Create mon grp and write pid into it for "mbm" and "cmt" test */
- if (!strncmp(resctrl_val, CMT_STR, sizeof(CMT_STR)) ||
- !strncmp(resctrl_val, MBM_STR, sizeof(MBM_STR))) {
- if (mongrp) {
- sprintf(monitorgroup_p, "%s/mon_groups", controlgroup);
- sprintf(monitorgroup, "%s/%s", monitorgroup_p, mongrp);
- ret = create_grp(mongrp, monitorgroup, monitorgroup_p);
- if (ret)
- goto out;
-
- sprintf(tasks, "%s/mon_groups/%s/tasks",
- controlgroup, mongrp);
- ret = write_pid_to_tasks(tasks, bm_pid);
- if (ret)
- goto out;
- }
+ /* Create monitor group and write pid into if it is used */
+ if (mongrp) {
+ sprintf(monitorgroup_p, "%s/mon_groups", controlgroup);
+ sprintf(monitorgroup, "%s/%s", monitorgroup_p, mongrp);
+ ret = create_grp(mongrp, monitorgroup, monitorgroup_p);
+ if (ret)
+ goto out;
+
+ sprintf(tasks, "%s/mon_groups/%s/tasks",
+ controlgroup, mongrp);
+ ret = write_pid_to_tasks(tasks, bm_pid);
+ if (ret)
+ goto out;
}

out:
--
2.39.2


2024-05-31 15:18:36

by Ilpo Järvinen

[permalink] [raw]
Subject: [PATCH v5 02/16] selftests/resctrl: Calculate resctrl FS derived mem bw over sleep(1) only

For MBM/MBA tests, measure_vals() calls get_mem_bw_imc() that performs
the measurement over a duration of sleep(1) call. The memory bandwidth
numbers from IMC are derived over this duration. The resctrl FS derived
memory bandwidth, however, is calculated inside measure_vals() and only
takes delta between the previous value and the current one which
besides the actual test, also samples inter-test noise.

Rework the logic in measure_vals() and get_mem_bw_imc() such that the
resctrl FS memory bandwidth section covers much shorter duration
closely matching that of the IMC perf counters to improve measurement
accuracy.

For the second read after rewind() to return a fresh value, also
newline has to be consumed by the fscanf().

Suggested-by: Reinette Chatre <[email protected]>
Signed-off-by: Ilpo Järvinen <[email protected]>
---

v5:
- Open mem bw file once and use rewind()
- Read \n from the mem bw file to allow rewind to return a new value.
v4:
- Open resctrl mem bw file (twice) beforehand to avoid opening it during
the test
v3:
- Don't drop Return: entry from perf_open_imc_mem_bw() func comment
---
tools/testing/selftests/resctrl/resctrl_val.c | 115 ++++++++++++------
1 file changed, 80 insertions(+), 35 deletions(-)

diff --git a/tools/testing/selftests/resctrl/resctrl_val.c b/tools/testing/selftests/resctrl/resctrl_val.c
index f55f5989de72..6231275a6e6c 100644
--- a/tools/testing/selftests/resctrl/resctrl_val.c
+++ b/tools/testing/selftests/resctrl/resctrl_val.c
@@ -306,18 +306,13 @@ static void perf_close_imc_mem_bw(void)
}

/*
- * get_mem_bw_imc: Memory band width as reported by iMC counters
- * @cpu_no: CPU number that the benchmark PID is binded to
- * @bw_report: Bandwidth report type (reads, writes)
- *
- * Memory B/W utilized by a process on a socket can be calculated using
- * iMC counters. Perf events are used to read these counters.
+ * perf_open_imc_mem_bw - Open perf fds for IMCs
+ * @cpu_no: CPU number that the benchmark PID is binded to
*
* Return: = 0 on success. < 0 on failure.
*/
-static int get_mem_bw_imc(int cpu_no, char *bw_report, float *bw_imc)
+static int perf_open_imc_mem_bw(int cpu_no)
{
- float reads, writes, of_mul_read, of_mul_write;
int imc, ret;

for (imc = 0; imc < imcs; imc++) {
@@ -325,8 +320,6 @@ static int get_mem_bw_imc(int cpu_no, char *bw_report, float *bw_imc)
imc_counters_config[imc][WRITE].fd = -1;
}

- /* Start all iMC counters to log values (both read and write) */
- reads = 0, writes = 0, of_mul_read = 1, of_mul_write = 1;
for (imc = 0; imc < imcs; imc++) {
ret = open_perf_event(imc, cpu_no, READ);
if (ret)
@@ -334,7 +327,26 @@ static int get_mem_bw_imc(int cpu_no, char *bw_report, float *bw_imc)
ret = open_perf_event(imc, cpu_no, WRITE);
if (ret)
goto close_fds;
+ }
+
+ return 0;
+
+close_fds:
+ perf_close_imc_mem_bw();
+ return -1;
+}

+/*
+ * do_mem_bw_test - Perform memory bandwidth test
+ *
+ * Runs memory bandwidth test over one second period. Also, handles starting
+ * and stopping of the IMC perf counters around the test.
+ */
+static void do_imc_mem_bw_test(void)
+{
+ int imc;
+
+ for (imc = 0; imc < imcs; imc++) {
membw_ioctl_perf_event_ioc_reset_enable(imc, READ);
membw_ioctl_perf_event_ioc_reset_enable(imc, WRITE);
}
@@ -346,6 +358,24 @@ static int get_mem_bw_imc(int cpu_no, char *bw_report, float *bw_imc)
membw_ioctl_perf_event_ioc_disable(imc, READ);
membw_ioctl_perf_event_ioc_disable(imc, WRITE);
}
+}
+
+/*
+ * get_mem_bw_imc - Memory band width as reported by iMC counters
+ * @bw_report: Bandwidth report type (reads, writes)
+ *
+ * Memory B/W utilized by a process on a socket can be calculated using
+ * iMC counters. Perf events are used to read these counters.
+ *
+ * Return: = 0 on success. < 0 on failure.
+ */
+static int get_mem_bw_imc(char *bw_report, float *bw_imc)
+{
+ float reads, writes, of_mul_read, of_mul_write;
+ int imc;
+
+ /* Start all iMC counters to log values (both read and write) */
+ reads = 0, writes = 0, of_mul_read = 1, of_mul_write = 1;

/*
* Get results which are stored in struct type imc_counter_config
@@ -462,24 +492,23 @@ static void initialize_mem_bw_resctrl(const char *ctrlgrp, const char *mongrp,
* 1. If con_mon grp is given, then read from it
* 2. If con_mon grp is not given, then read from root con_mon grp
*/
-static int get_mem_bw_resctrl(unsigned long *mbm_total)
+static FILE *open_mem_bw_resctrl(const char *mbm_bw_file)
{
FILE *fp;

- fp = fopen(mbm_total_path, "r");
- if (!fp) {
+ fp = fopen(mbm_bw_file, "r");
+ if (!fp)
ksft_perror("Failed to open total bw file");

- return -1;
- }
- if (fscanf(fp, "%lu", mbm_total) <= 0) {
- ksft_perror("Could not get mbm local bytes");
- fclose(fp);
+ return fp;
+}

+static int get_mem_bw_resctrl(FILE *fp, unsigned long *mbm_total)
+{
+ if (fscanf(fp, "%lu\n", mbm_total) <= 0) {
+ ksft_perror("Could not get mbm local bytes");
return -1;
}
- fclose(fp);
-
return 0;
}

@@ -616,13 +645,17 @@ static void initialize_llc_occu_resctrl(const char *ctrlgrp, const char *mongrp,
}

static int measure_vals(const struct user_params *uparams,
- struct resctrl_val_param *param,
- unsigned long *bw_resc_start)
+ struct resctrl_val_param *param)
{
- unsigned long bw_resc, bw_resc_end;
+ unsigned long bw_resc, bw_resc_start, bw_resc_end;
+ FILE *mem_bw_fp;
float bw_imc;
int ret;

+ mem_bw_fp = open_mem_bw_resctrl(mbm_total_path);
+ if (!mem_bw_fp)
+ return -1;
+
/*
* Measure memory bandwidth from resctrl and from
* another source which is perf imc value or could
@@ -630,22 +663,35 @@ static int measure_vals(const struct user_params *uparams,
* Compare the two values to validate resctrl value.
* It takes 1sec to measure the data.
*/
- ret = get_mem_bw_imc(uparams->cpu, param->bw_report, &bw_imc);
+ ret = perf_open_imc_mem_bw(uparams->cpu);
if (ret < 0)
- return ret;
+ goto close_fp;

- ret = get_mem_bw_resctrl(&bw_resc_end);
+ ret = get_mem_bw_resctrl(mem_bw_fp, &bw_resc_start);
if (ret < 0)
- return ret;
+ goto close_fp;

- bw_resc = (bw_resc_end - *bw_resc_start) / MB;
- ret = print_results_bw(param->filename, bm_pid, bw_imc, bw_resc);
- if (ret)
- return ret;
+ rewind(mem_bw_fp);

- *bw_resc_start = bw_resc_end;
+ do_imc_mem_bw_test();

- return 0;
+ ret = get_mem_bw_resctrl(mem_bw_fp, &bw_resc_end);
+ if (ret < 0)
+ goto close_fp;
+
+ ret = get_mem_bw_imc(param->bw_report, &bw_imc);
+ if (ret < 0)
+ goto close_fp;
+
+ fclose(mem_bw_fp);
+
+ bw_resc = (bw_resc_end - bw_resc_start) / MB;
+
+ return print_results_bw(param->filename, bm_pid, bw_imc, bw_resc);
+
+close_fp:
+ fclose(mem_bw_fp);
+ return ret;
}

/*
@@ -719,7 +765,6 @@ int resctrl_val(const struct resctrl_test *test,
struct resctrl_val_param *param)
{
char *resctrl_val = param->resctrl_val;
- unsigned long bw_resc_start = 0;
struct sigaction sigact;
int ret = 0, pipefd[2];
char pipe_message = 0;
@@ -861,7 +906,7 @@ int resctrl_val(const struct resctrl_test *test,

if (!strncmp(resctrl_val, MBM_STR, sizeof(MBM_STR)) ||
!strncmp(resctrl_val, MBA_STR, sizeof(MBA_STR))) {
- ret = measure_vals(uparams, param, &bw_resc_start);
+ ret = measure_vals(uparams, param);
if (ret)
break;
} else if (!strncmp(resctrl_val, CMT_STR, sizeof(CMT_STR))) {
--
2.39.2


2024-05-31 15:38:06

by Ilpo Järvinen

[permalink] [raw]
Subject: [PATCH v5 13/16] selftests/resctrl: Convert ctrlgrp & mongrp to pointers

The struct resctrl_val_param has control and monitor groups as char
arrays but they are not supposed to be mutated within resctrl_val().

Convert the ctrlgrp and mongrp char array within resctrl_val_param to
plain const char pointers and adjust the strlen() based checks to
check NULL instead.

Convert !grp_name check in create_grp() into internal sanity check by
returning error if the caller asked to create a group but doesn't
provide a name for the group. The existing code already abides this by
only calling create_grp() if mongrp is non-NULL so the error should
never be returned with the current selftests (ctrlgrp is never NULL).

Signed-off-by: Ilpo Järvinen <[email protected]>
---
v5:
- Return 0 if grp_name is null (restore earlier behavior)
- Move the root group note from comment into kerneldoc

v3:
- Removed wrong comment
- Changed grp_name check to return -1 on fail (internal sanity check)
---
tools/testing/selftests/resctrl/resctrl.h | 4 ++--
tools/testing/selftests/resctrl/resctrlfs.c | 16 +++++++---------
2 files changed, 9 insertions(+), 11 deletions(-)

diff --git a/tools/testing/selftests/resctrl/resctrl.h b/tools/testing/selftests/resctrl/resctrl.h
index 5967389038d4..a999fbc13fd3 100644
--- a/tools/testing/selftests/resctrl/resctrl.h
+++ b/tools/testing/selftests/resctrl/resctrl.h
@@ -91,8 +91,8 @@ struct resctrl_test {
*/
struct resctrl_val_param {
char *resctrl_val;
- char ctrlgrp[64];
- char mongrp[64];
+ const char *ctrlgrp;
+ const char *mongrp;
char filename[64];
unsigned long mask;
int num_of_runs;
diff --git a/tools/testing/selftests/resctrl/resctrlfs.c b/tools/testing/selftests/resctrl/resctrlfs.c
index f4dc8ef23a8c..893041faaf18 100644
--- a/tools/testing/selftests/resctrl/resctrlfs.c
+++ b/tools/testing/selftests/resctrl/resctrlfs.c
@@ -456,6 +456,9 @@ int taskset_restore(pid_t bm_pid, cpu_set_t *old_affinity)
* @grp: Full path and name of the group
* @parent_grp: Full path and name of the parent group
*
+ * Creates a group @grp_name if it does not exist yet. If @grp_name is NULL,
+ * it is interpreted as the root group which always results success.
+ *
* Return: 0 on success, < 0 on error.
*/
static int create_grp(const char *grp_name, char *grp, const char *parent_grp)
@@ -464,12 +467,7 @@ 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)
+ if (!grp_name)
return 0;

/* Check if requested grp exists or not */
@@ -541,7 +539,7 @@ int write_bm_pid_to_resctrl(pid_t bm_pid, const char *ctrlgrp,
char tasks[1024];
int ret = 0;

- if (strlen(ctrlgrp))
+ if (ctrlgrp)
sprintf(controlgroup, "%s/%s", RESCTRL_PATH, ctrlgrp);
else
sprintf(controlgroup, "%s", RESCTRL_PATH);
@@ -558,7 +556,7 @@ int write_bm_pid_to_resctrl(pid_t bm_pid, const char *ctrlgrp,
/* Create mon grp and write pid into it for "mbm" and "cmt" test */
if (!strncmp(resctrl_val, CMT_STR, sizeof(CMT_STR)) ||
!strncmp(resctrl_val, MBM_STR, sizeof(MBM_STR))) {
- if (strlen(mongrp)) {
+ if (mongrp) {
sprintf(monitorgroup_p, "%s/mon_groups", controlgroup);
sprintf(monitorgroup, "%s/%s", monitorgroup_p, mongrp);
ret = create_grp(mongrp, monitorgroup, monitorgroup_p);
@@ -612,7 +610,7 @@ int write_schemata(const char *ctrlgrp, char *schemata, int cpu_no,
goto out;
}

- if (strlen(ctrlgrp) != 0)
+ if (ctrlgrp)
sprintf(controlgroup, "%s/%s/schemata", RESCTRL_PATH, ctrlgrp);
else
sprintf(controlgroup, "%s/schemata", RESCTRL_PATH);
--
2.39.2


2024-05-31 15:42:53

by Ilpo Järvinen

[permalink] [raw]
Subject: [PATCH v5 12/16] selftests/resctrl: Make some strings passed to resctrlfs functions const

Control group, monitor group and resctrl_val are not mutated and
should not be mutated within resctrlfs.c functions.

Mark this by using const char * for the arguments.

Signed-off-by: Ilpo Järvinen <[email protected]>
Reviewed-by: Reinette Chatre <[email protected]>
---
tools/testing/selftests/resctrl/resctrl.h | 7 ++++---
tools/testing/selftests/resctrl/resctrlfs.c | 7 ++++---
2 files changed, 8 insertions(+), 6 deletions(-)

diff --git a/tools/testing/selftests/resctrl/resctrl.h b/tools/testing/selftests/resctrl/resctrl.h
index 4446a0e493ef..5967389038d4 100644
--- a/tools/testing/selftests/resctrl/resctrl.h
+++ b/tools/testing/selftests/resctrl/resctrl.h
@@ -141,9 +141,10 @@ bool test_resource_feature_check(const struct resctrl_test *test);
char *fgrep(FILE *inf, const char *str);
int taskset_benchmark(pid_t bm_pid, int cpu_no, cpu_set_t *old_affinity);
int taskset_restore(pid_t bm_pid, cpu_set_t *old_affinity);
-int write_schemata(char *ctrlgrp, char *schemata, int cpu_no, const char *resource);
-int write_bm_pid_to_resctrl(pid_t bm_pid, char *ctrlgrp, char *mongrp,
- char *resctrl_val);
+int write_schemata(const char *ctrlgrp, char *schemata, int cpu_no,
+ const char *resource);
+int write_bm_pid_to_resctrl(pid_t bm_pid, const char *ctrlgrp,
+ const char *mongrp, const char *resctrl_val);
int perf_event_open(struct perf_event_attr *hw_event, pid_t pid, int cpu,
int group_fd, unsigned long flags);
unsigned char *alloc_buffer(size_t buf_size, int memflush);
diff --git a/tools/testing/selftests/resctrl/resctrlfs.c b/tools/testing/selftests/resctrl/resctrlfs.c
index 9e4cda154d66..f4dc8ef23a8c 100644
--- a/tools/testing/selftests/resctrl/resctrlfs.c
+++ b/tools/testing/selftests/resctrl/resctrlfs.c
@@ -534,8 +534,8 @@ static int write_pid_to_tasks(char *tasks, pid_t pid)
*
* Return: 0 on success, < 0 on error.
*/
-int write_bm_pid_to_resctrl(pid_t bm_pid, char *ctrlgrp, char *mongrp,
- char *resctrl_val)
+int write_bm_pid_to_resctrl(pid_t bm_pid, const char *ctrlgrp,
+ const char *mongrp, const char *resctrl_val)
{
char controlgroup[128], monitorgroup[512], monitorgroup_p[256];
char tasks[1024];
@@ -593,7 +593,8 @@ int write_bm_pid_to_resctrl(pid_t bm_pid, char *ctrlgrp, char *mongrp,
*
* Return: 0 on success, < 0 on error.
*/
-int write_schemata(char *ctrlgrp, char *schemata, int cpu_no, const char *resource)
+int write_schemata(const char *ctrlgrp, char *schemata, int cpu_no,
+ const char *resource)
{
char controlgroup[1024], reason[128], schema[1024] = {};
int domain_id, fd, schema_len, ret = 0;
--
2.39.2


2024-05-31 15:47:12

by Ilpo Järvinen

[permalink] [raw]
Subject: [PATCH v5 07/16] selftests/resctrl: Rename measure_vals() to measure_mem_bw_vals() & document

measure_vals() is awfully generic name so rename it to measure_mem_bw()
to describe better what it does and document the function parameters.

Signed-off-by: Ilpo Järvinen <[email protected]>
Reviewed-by: Reinette Chatre <[email protected]>
---

v5:
- Typo fix to commit message
- Consistent caps in kerneldoc
---
tools/testing/selftests/resctrl/resctrl_val.c | 12 +++++++++---
1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/tools/testing/selftests/resctrl/resctrl_val.c b/tools/testing/selftests/resctrl/resctrl_val.c
index 3939a657de4a..e3670b8bc317 100644
--- a/tools/testing/selftests/resctrl/resctrl_val.c
+++ b/tools/testing/selftests/resctrl/resctrl_val.c
@@ -637,8 +637,14 @@ static void initialize_llc_occu_resctrl(const char *ctrlgrp, const char *mongrp,
set_cmt_path(ctrlgrp, mongrp, domain_id);
}

-static int measure_vals(const struct user_params *uparams,
- struct resctrl_val_param *param, pid_t bm_pid)
+/*
+ * measure_mem_bw - Measures memory bandwidth numbers while benchmark runs
+ * @uparams: User supplied parameters
+ * @param: Parameters passed to resctrl_val()
+ * @bm_pid: PID that runs the benchmark
+ */
+static int measure_mem_bw(const struct user_params *uparams,
+ struct resctrl_val_param *param, pid_t bm_pid)
{
unsigned long bw_resc, bw_resc_start, bw_resc_end;
FILE *mem_bw_fp;
@@ -906,7 +912,7 @@ int resctrl_val(const struct resctrl_test *test,

if (!strncmp(resctrl_val, MBM_STR, sizeof(MBM_STR)) ||
!strncmp(resctrl_val, MBA_STR, sizeof(MBA_STR))) {
- ret = measure_vals(uparams, param, bm_pid);
+ ret = measure_mem_bw(uparams, param, bm_pid);
if (ret)
break;
} else if (!strncmp(resctrl_val, CMT_STR, sizeof(CMT_STR))) {
--
2.39.2


2024-05-31 15:50:06

by Ilpo Järvinen

[permalink] [raw]
Subject: [PATCH v5 08/16] selftests/resctrl: Simplify mem bandwidth file code for MBA & MBM tests

initialize_mem_bw_resctrl() and set_mbm_path() contain complicated set
of conditions, each yielding different file to be opened to measure
memory bandwidth through resctrl FS. In practice, only two of them are
used. For MBA test, ctrlgrp is always provided, and for MBM test both
ctrlgrp and mongrp are set.

The file used differ between MBA/MBM test, however, MBM test
unnecessarily create monitor group because resctrl FS already provides
monitoring interface underneath any ctrlgrp too, which is what the MBA
selftest uses.

Consolidate memory bandwidth file used to the one used by the MBA
selftest. Remove all unused branches opening other files to simplify
the code.

Suggested-by: Reinette Chatre <[email protected]>
Signed-off-by: Ilpo Järvinen <[email protected]>
Reviewed-by: Reinette Chatre <[email protected]>
---

v4:
- Remove also MBM .mongrp setup
v3:
- New patch
---
tools/testing/selftests/resctrl/mbm_test.c | 1 -
tools/testing/selftests/resctrl/resctrl_val.c | 45 ++-----------------
2 files changed, 4 insertions(+), 42 deletions(-)

diff --git a/tools/testing/selftests/resctrl/mbm_test.c b/tools/testing/selftests/resctrl/mbm_test.c
index 3059ccc51a5a..96d279b06377 100644
--- a/tools/testing/selftests/resctrl/mbm_test.c
+++ b/tools/testing/selftests/resctrl/mbm_test.c
@@ -115,7 +115,6 @@ static int mbm_run_test(const struct resctrl_test *test, const struct user_param
struct resctrl_val_param param = {
.resctrl_val = MBM_STR,
.ctrlgrp = "c1",
- .mongrp = "m1",
.filename = RESULT_FILE_NAME,
.bw_report = "reads",
.setup = mbm_setup
diff --git a/tools/testing/selftests/resctrl/resctrl_val.c b/tools/testing/selftests/resctrl/resctrl_val.c
index e3670b8bc317..2a10b50c9e2a 100644
--- a/tools/testing/selftests/resctrl/resctrl_val.c
+++ b/tools/testing/selftests/resctrl/resctrl_val.c
@@ -19,18 +19,10 @@
#define MAX_TOKENS 5
#define READ 0
#define WRITE 1
-#define CON_MON_MBM_LOCAL_BYTES_PATH \
- "%s/%s/mon_groups/%s/mon_data/mon_L3_%02d/mbm_local_bytes"

#define CON_MBM_LOCAL_BYTES_PATH \
"%s/%s/mon_data/mon_L3_%02d/mbm_local_bytes"

-#define MON_MBM_LOCAL_BYTES_PATH \
- "%s/mon_groups/%s/mon_data/mon_L3_%02d/mbm_local_bytes"
-
-#define MBM_LOCAL_BYTES_PATH \
- "%s/mon_data/mon_L3_%02d/mbm_local_bytes"
-
#define CON_MON_LCC_OCCUP_PATH \
"%s/%s/mon_groups/%s/mon_data/mon_L3_%02d/llc_occupancy"

@@ -436,43 +428,15 @@ static int get_mem_bw_imc(char *bw_report, float *bw_imc)
return -1;
}

-void set_mbm_path(const char *ctrlgrp, const char *mongrp, int domain_id)
-{
- if (ctrlgrp && mongrp)
- sprintf(mbm_total_path, CON_MON_MBM_LOCAL_BYTES_PATH,
- RESCTRL_PATH, ctrlgrp, mongrp, domain_id);
- else if (!ctrlgrp && mongrp)
- sprintf(mbm_total_path, MON_MBM_LOCAL_BYTES_PATH, RESCTRL_PATH,
- mongrp, domain_id);
- else if (ctrlgrp && !mongrp)
- sprintf(mbm_total_path, CON_MBM_LOCAL_BYTES_PATH, RESCTRL_PATH,
- ctrlgrp, domain_id);
- else if (!ctrlgrp && !mongrp)
- sprintf(mbm_total_path, MBM_LOCAL_BYTES_PATH, RESCTRL_PATH,
- domain_id);
-}
-
/*
* initialize_mem_bw_resctrl: Appropriately populate "mbm_total_path"
* @ctrlgrp: Name of the control monitor group (con_mon grp)
- * @mongrp: Name of the monitor group (mon grp)
* @domain_id: Domain ID (cache ID; for MB, L3 cache ID)
- * @resctrl_val: Resctrl feature (Eg: mbm, mba.. etc)
*/
-static void initialize_mem_bw_resctrl(const char *ctrlgrp, const char *mongrp,
- int domain_id, char *resctrl_val)
+static void initialize_mem_bw_resctrl(const char *ctrlgrp, int domain_id)
{
- if (!strncmp(resctrl_val, MBM_STR, sizeof(MBM_STR)))
- set_mbm_path(ctrlgrp, mongrp, domain_id);
-
- if (!strncmp(resctrl_val, MBA_STR, sizeof(MBA_STR))) {
- if (ctrlgrp)
- sprintf(mbm_total_path, CON_MBM_LOCAL_BYTES_PATH,
- RESCTRL_PATH, ctrlgrp, domain_id);
- else
- sprintf(mbm_total_path, MBM_LOCAL_BYTES_PATH,
- RESCTRL_PATH, domain_id);
- }
+ sprintf(mbm_total_path, CON_MBM_LOCAL_BYTES_PATH, RESCTRL_PATH,
+ ctrlgrp, domain_id);
}

/*
@@ -872,8 +836,7 @@ int resctrl_val(const struct resctrl_test *test,
if (ret)
goto out;

- initialize_mem_bw_resctrl(param->ctrlgrp, param->mongrp,
- domain_id, resctrl_val);
+ initialize_mem_bw_resctrl(param->ctrlgrp, domain_id);
} else if (!strncmp(resctrl_val, CMT_STR, sizeof(CMT_STR)))
initialize_llc_occu_resctrl(param->ctrlgrp, param->mongrp,
domain_id, resctrl_val);
--
2.39.2


2024-05-31 16:12:59

by Ilpo Järvinen

[permalink] [raw]
Subject: [PATCH v5 06/16] selftests/resctrl: Cleanup bm_pid and ppid usage & limit scope

'bm_pid' and 'ppid' are global variables. As they are used by different
processes and in signal handler, they cannot be entirely converted into
local variables.

The scope of those variables can still be reduced into resctrl_val.c
only. As PARENT_EXIT() macro is using 'ppid', make it a function in
resctrl_val.c and pass ppid to it as an argument because it is easier
to understand than using the global variable directly.

Pass 'bm_pid' into measure_vals() instead of relying on the global
variable which helps to make the call signatures of measure_vals() and
measure_llc_resctrl() more similar to each other.

Signed-off-by: Ilpo Järvinen <[email protected]>
Reviewed-by: Reinette Chatre <[email protected]>
---
tools/testing/selftests/resctrl/resctrl.h | 9 --------
tools/testing/selftests/resctrl/resctrl_val.c | 23 ++++++++++++-------
2 files changed, 15 insertions(+), 17 deletions(-)

diff --git a/tools/testing/selftests/resctrl/resctrl.h b/tools/testing/selftests/resctrl/resctrl.h
index e6f221236c79..e4b6dc672ecc 100644
--- a/tools/testing/selftests/resctrl/resctrl.h
+++ b/tools/testing/selftests/resctrl/resctrl.h
@@ -43,13 +43,6 @@

#define DEFAULT_SPAN (250 * MB)

-#define PARENT_EXIT() \
- do { \
- kill(ppid, SIGKILL); \
- umount_resctrlfs(); \
- exit(EXIT_FAILURE); \
- } while (0)
-
/*
* user_params: User supplied parameters
* @cpu: CPU number to which the benchmark will be bound to
@@ -127,8 +120,6 @@ struct perf_event_read {
*/
extern volatile int *value_sink;

-extern pid_t bm_pid, ppid;
-
extern char llc_occup_path[1024];

int get_vendor(void);
diff --git a/tools/testing/selftests/resctrl/resctrl_val.c b/tools/testing/selftests/resctrl/resctrl_val.c
index d6f6db77d480..3939a657de4a 100644
--- a/tools/testing/selftests/resctrl/resctrl_val.c
+++ b/tools/testing/selftests/resctrl/resctrl_val.c
@@ -505,7 +505,7 @@ static int get_mem_bw_resctrl(FILE *fp, unsigned long *mbm_total)
return 0;
}

-pid_t bm_pid, ppid;
+static pid_t bm_pid, ppid;

void ctrlc_handler(int signum, siginfo_t *info, void *ptr)
{
@@ -563,6 +563,13 @@ void signal_handler_unregister(void)
}
}

+static void parent_exit(pid_t ppid)
+{
+ kill(ppid, SIGKILL);
+ umount_resctrlfs();
+ exit(EXIT_FAILURE);
+}
+
/*
* print_results_bw: the memory bandwidth results are stored in a file
* @filename: file that stores the results
@@ -631,7 +638,7 @@ static void initialize_llc_occu_resctrl(const char *ctrlgrp, const char *mongrp,
}

static int measure_vals(const struct user_params *uparams,
- struct resctrl_val_param *param)
+ struct resctrl_val_param *param, pid_t bm_pid)
{
unsigned long bw_resc, bw_resc_start, bw_resc_end;
FILE *mem_bw_fp;
@@ -704,7 +711,7 @@ static void run_benchmark(int signum, siginfo_t *info, void *ucontext)
fp = freopen("/dev/null", "w", stdout);
if (!fp) {
ksft_perror("Unable to direct benchmark status to /dev/null");
- PARENT_EXIT();
+ parent_exit(ppid);
}

if (strcmp(benchmark_cmd[0], "fill_buf") == 0) {
@@ -718,7 +725,7 @@ static void run_benchmark(int signum, siginfo_t *info, void *ucontext)
once = false;
} else {
ksft_print_msg("Invalid once parameter\n");
- PARENT_EXIT();
+ parent_exit(ppid);
}

if (run_fill_buf(span, memflush, operation, once))
@@ -732,7 +739,7 @@ static void run_benchmark(int signum, siginfo_t *info, void *ucontext)

fclose(stdout);
ksft_print_msg("Unable to run specified benchmark\n");
- PARENT_EXIT();
+ parent_exit(ppid);
}

/*
@@ -811,7 +818,7 @@ int resctrl_val(const struct resctrl_test *test,
/* Register for "SIGUSR1" signal from parent */
if (sigaction(SIGUSR1, &sigact, NULL)) {
ksft_perror("Can't register child for signal");
- PARENT_EXIT();
+ parent_exit(ppid);
}

/* Tell parent that child is ready */
@@ -829,7 +836,7 @@ int resctrl_val(const struct resctrl_test *test,
sigsuspend(&sigact.sa_mask);

ksft_perror("Child is done");
- PARENT_EXIT();
+ parent_exit(ppid);
}

ksft_print_msg("Benchmark PID: %d\n", (int)bm_pid);
@@ -899,7 +906,7 @@ int resctrl_val(const struct resctrl_test *test,

if (!strncmp(resctrl_val, MBM_STR, sizeof(MBM_STR)) ||
!strncmp(resctrl_val, MBA_STR, sizeof(MBA_STR))) {
- ret = measure_vals(uparams, param);
+ ret = measure_vals(uparams, param, bm_pid);
if (ret)
break;
} else if (!strncmp(resctrl_val, CMT_STR, sizeof(CMT_STR))) {
--
2.39.2


2024-05-31 16:23:08

by Ilpo Järvinen

[permalink] [raw]
Subject: [PATCH v5 09/16] selftests/resctrl: Add ->measure() callback to resctrl_val_param

The measurement done in resctrl_val() varies depending on test type.
The decision for how to measure is decided based on the string compare
to test name which is quite inflexible.

Add ->measure() callback into the struct resctrl_val_param to allow
each test to provide necessary code as a function which simplifies what
resctrl_val() has to do.

Signed-off-by: Ilpo Järvinen <[email protected]>
Reviewed-by: Reinette Chatre <[email protected]>
---

v2:
- spaces -> tabs
---
tools/testing/selftests/resctrl/cmt_test.c | 8 ++++++++
tools/testing/selftests/resctrl/mba_test.c | 9 ++++++++-
tools/testing/selftests/resctrl/mbm_test.c | 9 ++++++++-
tools/testing/selftests/resctrl/resctrl.h | 6 ++++++
tools/testing/selftests/resctrl/resctrl_val.c | 18 +++++-------------
5 files changed, 35 insertions(+), 15 deletions(-)

diff --git a/tools/testing/selftests/resctrl/cmt_test.c b/tools/testing/selftests/resctrl/cmt_test.c
index a44e6fcd37b7..d8521386cd18 100644
--- a/tools/testing/selftests/resctrl/cmt_test.c
+++ b/tools/testing/selftests/resctrl/cmt_test.c
@@ -29,6 +29,13 @@ static int cmt_setup(const struct resctrl_test *test,
return 0;
}

+static int cmt_measure(const struct user_params *uparams,
+ struct resctrl_val_param *param, pid_t bm_pid)
+{
+ sleep(1);
+ return measure_llc_resctrl(param->filename, bm_pid);
+}
+
static int show_results_info(unsigned long sum_llc_val, int no_of_bits,
unsigned long cache_span, unsigned long max_diff,
unsigned long max_diff_percent, unsigned long num_of_runs,
@@ -133,6 +140,7 @@ static int cmt_run_test(const struct resctrl_test *test, const struct user_param
.mask = ~(long_mask << n) & long_mask,
.num_of_runs = 0,
.setup = cmt_setup,
+ .measure = cmt_measure,
};

span = cache_portion_size(cache_total_size, param.mask, long_mask);
diff --git a/tools/testing/selftests/resctrl/mba_test.c b/tools/testing/selftests/resctrl/mba_test.c
index 5d6af9e8afed..de6e29faf214 100644
--- a/tools/testing/selftests/resctrl/mba_test.c
+++ b/tools/testing/selftests/resctrl/mba_test.c
@@ -51,6 +51,12 @@ static int mba_setup(const struct resctrl_test *test,
return 0;
}

+static int mba_measure(const struct user_params *uparams,
+ struct resctrl_val_param *param, pid_t bm_pid)
+{
+ return measure_mem_bw(uparams, param, bm_pid);
+}
+
static bool show_mba_info(unsigned long *bw_imc, unsigned long *bw_resc)
{
int allocation, runs;
@@ -150,7 +156,8 @@ static int mba_run_test(const struct resctrl_test *test, const struct user_param
.mongrp = "m1",
.filename = RESULT_FILE_NAME,
.bw_report = "reads",
- .setup = mba_setup
+ .setup = mba_setup,
+ .measure = mba_measure,
};
int ret;

diff --git a/tools/testing/selftests/resctrl/mbm_test.c b/tools/testing/selftests/resctrl/mbm_test.c
index 96d279b06377..59e26adf60bb 100644
--- a/tools/testing/selftests/resctrl/mbm_test.c
+++ b/tools/testing/selftests/resctrl/mbm_test.c
@@ -105,6 +105,12 @@ static int mbm_setup(const struct resctrl_test *test,
return ret;
}

+static int mbm_measure(const struct user_params *uparams,
+ struct resctrl_val_param *param, pid_t bm_pid)
+{
+ return measure_mem_bw(uparams, param, bm_pid);
+}
+
static void mbm_test_cleanup(void)
{
remove(RESULT_FILE_NAME);
@@ -117,7 +123,8 @@ static int mbm_run_test(const struct resctrl_test *test, const struct user_param
.ctrlgrp = "c1",
.filename = RESULT_FILE_NAME,
.bw_report = "reads",
- .setup = mbm_setup
+ .setup = mbm_setup,
+ .measure = mbm_measure,
};
int ret;

diff --git a/tools/testing/selftests/resctrl/resctrl.h b/tools/testing/selftests/resctrl/resctrl.h
index e4b6dc672ecc..5dc3def70669 100644
--- a/tools/testing/selftests/resctrl/resctrl.h
+++ b/tools/testing/selftests/resctrl/resctrl.h
@@ -87,6 +87,7 @@ struct resctrl_test {
* @filename: Name of file to which the o/p should be written
* @bw_report: Bandwidth report type (reads vs writes)
* @setup: Call back function to setup test environment
+ * @measure: Callback that performs the measurement (a single test)
*/
struct resctrl_val_param {
char *resctrl_val;
@@ -99,6 +100,9 @@ struct resctrl_val_param {
int (*setup)(const struct resctrl_test *test,
const struct user_params *uparams,
struct resctrl_val_param *param);
+ int (*measure)(const struct user_params *uparams,
+ struct resctrl_val_param *param,
+ pid_t bm_pid);
};

struct perf_event_read {
@@ -145,6 +149,8 @@ unsigned char *alloc_buffer(size_t buf_size, int memflush);
void mem_flush(unsigned char *buf, size_t buf_size);
void fill_cache_read(unsigned char *buf, size_t buf_size, bool once);
int run_fill_buf(size_t buf_size, int memflush, int op, bool once);
+int measure_mem_bw(const struct user_params *uparams,
+ struct resctrl_val_param *param, pid_t bm_pid);
int resctrl_val(const struct resctrl_test *test,
const struct user_params *uparams,
const char * const *benchmark_cmd,
diff --git a/tools/testing/selftests/resctrl/resctrl_val.c b/tools/testing/selftests/resctrl/resctrl_val.c
index 2a10b50c9e2a..47d58c9aed28 100644
--- a/tools/testing/selftests/resctrl/resctrl_val.c
+++ b/tools/testing/selftests/resctrl/resctrl_val.c
@@ -607,8 +607,8 @@ static void initialize_llc_occu_resctrl(const char *ctrlgrp, const char *mongrp,
* @param: Parameters passed to resctrl_val()
* @bm_pid: PID that runs the benchmark
*/
-static int measure_mem_bw(const struct user_params *uparams,
- struct resctrl_val_param *param, pid_t bm_pid)
+int measure_mem_bw(const struct user_params *uparams,
+ struct resctrl_val_param *param, pid_t bm_pid)
{
unsigned long bw_resc, bw_resc_start, bw_resc_end;
FILE *mem_bw_fp;
@@ -873,17 +873,9 @@ int resctrl_val(const struct resctrl_test *test,
if (ret < 0)
break;

- if (!strncmp(resctrl_val, MBM_STR, sizeof(MBM_STR)) ||
- !strncmp(resctrl_val, MBA_STR, sizeof(MBA_STR))) {
- ret = measure_mem_bw(uparams, param, bm_pid);
- if (ret)
- break;
- } else if (!strncmp(resctrl_val, CMT_STR, sizeof(CMT_STR))) {
- sleep(1);
- ret = measure_llc_resctrl(param->filename, bm_pid);
- if (ret)
- break;
- }
+ ret = param->measure(uparams, param, bm_pid);
+ if (ret)
+ break;
}

out:
--
2.39.2


2024-05-31 17:21:00

by Ilpo Järvinen

[permalink] [raw]
Subject: [PATCH v5 14/16] selftests/resctrl: Remove mongrp from MBA test

Nothing during MBA test uses mongrp even if it has been defined ever
since the introduction of the MBA test in the commit 01fee6b4d1f9
("selftests/resctrl: Add MBA test").

Remove the mongrp from MBA test.

Signed-off-by: Ilpo Järvinen <[email protected]>
Reviewed-by: Reinette Chatre <[email protected]>
---
tools/testing/selftests/resctrl/mba_test.c | 1 -
1 file changed, 1 deletion(-)

diff --git a/tools/testing/selftests/resctrl/mba_test.c b/tools/testing/selftests/resctrl/mba_test.c
index 9c9a4f22e529..5e0b1e794295 100644
--- a/tools/testing/selftests/resctrl/mba_test.c
+++ b/tools/testing/selftests/resctrl/mba_test.c
@@ -166,7 +166,6 @@ static int mba_run_test(const struct resctrl_test *test, const struct user_param
struct resctrl_val_param param = {
.resctrl_val = MBA_STR,
.ctrlgrp = "c1",
- .mongrp = "m1",
.filename = RESULT_FILE_NAME,
.init = mba_init,
.setup = mba_setup,
--
2.39.2


2024-05-31 17:29:29

by Ilpo Järvinen

[permalink] [raw]
Subject: [PATCH v5 04/16] selftests/resctrl: Consolidate get_domain_id() into resctrl_val()

Both initialize_mem_bw_resctrl() and initialize_llc_occu_resctrl() that
are called from resctrl_val() need to determine domain ID to construct
resctrl fs related paths. Both functions do it by taking CPU ID which
neither needs for any other purpose than determining the domain ID.

Consolidate determining the domain ID into resctrl_val() and pass the
domain ID instead of CPU ID to initialize_mem_bw_resctrl() and
initialize_llc_occu_resctrl().

Signed-off-by: Ilpo Järvinen <[email protected]>
Reviewed-by: Reinette Chatre <[email protected]>
---
tools/testing/selftests/resctrl/resctrl_val.c | 33 ++++++++-----------
1 file changed, 13 insertions(+), 20 deletions(-)

diff --git a/tools/testing/selftests/resctrl/resctrl_val.c b/tools/testing/selftests/resctrl/resctrl_val.c
index cb646168179e..e1ae59063c51 100644
--- a/tools/testing/selftests/resctrl/resctrl_val.c
+++ b/tools/testing/selftests/resctrl/resctrl_val.c
@@ -456,19 +456,12 @@ void set_mbm_path(const char *ctrlgrp, const char *mongrp, int domain_id)
* initialize_mem_bw_resctrl: Appropriately populate "mbm_total_path"
* @ctrlgrp: Name of the control monitor group (con_mon grp)
* @mongrp: Name of the monitor group (mon grp)
- * @cpu_no: CPU number that the benchmark PID is binded to
+ * @domain_id: Domain ID (cache ID; for MB, L3 cache ID)
* @resctrl_val: Resctrl feature (Eg: mbm, mba.. etc)
*/
static void initialize_mem_bw_resctrl(const char *ctrlgrp, const char *mongrp,
- int cpu_no, char *resctrl_val)
+ int domain_id, char *resctrl_val)
{
- int domain_id;
-
- if (get_domain_id("MB", cpu_no, &domain_id) < 0) {
- ksft_print_msg("Could not get domain ID\n");
- return;
- }
-
if (!strncmp(resctrl_val, MBM_STR, sizeof(MBM_STR)))
set_mbm_path(ctrlgrp, mongrp, domain_id);

@@ -627,19 +620,12 @@ static void set_cmt_path(const char *ctrlgrp, const char *mongrp, char sock_num)
* initialize_llc_occu_resctrl: Appropriately populate "llc_occup_path"
* @ctrlgrp: Name of the control monitor group (con_mon grp)
* @mongrp: Name of the monitor group (mon grp)
- * @cpu_no: CPU number that the benchmark PID is binded to
+ * @domain_id: Domain ID (cache ID; for MB, L3 cache ID)
* @resctrl_val: Resctrl feature (Eg: cat, cmt.. etc)
*/
static void initialize_llc_occu_resctrl(const char *ctrlgrp, const char *mongrp,
- int cpu_no, char *resctrl_val)
+ int domain_id, char *resctrl_val)
{
- int domain_id;
-
- if (get_domain_id("L3", cpu_no, &domain_id) < 0) {
- ksft_print_msg("Could not get domain ID\n");
- return;
- }
-
if (!strncmp(resctrl_val, CMT_STR, sizeof(CMT_STR)))
set_cmt_path(ctrlgrp, mongrp, domain_id);
}
@@ -769,10 +755,17 @@ int resctrl_val(const struct resctrl_test *test,
int ret = 0, pipefd[2];
char pipe_message = 0;
union sigval value;
+ int domain_id;

if (strcmp(param->filename, "") == 0)
sprintf(param->filename, "stdio");

+ ret = get_domain_id(test->resource, uparams->cpu, &domain_id);
+ if (ret < 0) {
+ ksft_print_msg("Could not get domain ID\n");
+ return ret;
+ }
+
if (!strncmp(resctrl_val, MBA_STR, sizeof(MBA_STR)) ||
!strncmp(resctrl_val, MBM_STR, sizeof(MBM_STR))) {
ret = validate_bw_report_request(param->bw_report);
@@ -867,10 +860,10 @@ int resctrl_val(const struct resctrl_test *test,
goto out;

initialize_mem_bw_resctrl(param->ctrlgrp, param->mongrp,
- uparams->cpu, resctrl_val);
+ domain_id, resctrl_val);
} else if (!strncmp(resctrl_val, CMT_STR, sizeof(CMT_STR)))
initialize_llc_occu_resctrl(param->ctrlgrp, param->mongrp,
- uparams->cpu, resctrl_val);
+ domain_id, resctrl_val);

/* Parent waits for child to be ready. */
close(pipefd[1]);
--
2.39.2


2024-05-31 17:34:04

by Ilpo Järvinen

[permalink] [raw]
Subject: [PATCH v5 10/16] selftests/resctrl: Add ->init() callback into resctrl_val_param

The struct resctrl_val_param is there to customize behavior inside
resctrl_val() which is currently not used to full extent and there are
number of strcmp()s for test name in resctrl_val done by resctrl_val().

Create ->init() hook into the struct resctrl_val_param to cleanly
do per test initialization.

Remove also unused branches to setup paths and the related #defines
for CMT test.

While touching kerneldoc, make the adjacent line consistent with the
newly added form (callback vs call back).

Signed-off-by: Ilpo Järvinen <[email protected]>
Reviewed-by: Reinette Chatre <[email protected]>
---

v5:
- Use consistent formatting in kerneldoc
v3:
- Rename init functions to <testname>_init()
- Removed tabs intermixed with code
- Leave now common mbm bw filename setup into resctrl_val.c
---
tools/testing/selftests/resctrl/cmt_test.c | 12 +++
tools/testing/selftests/resctrl/mba_test.c | 14 ++++
tools/testing/selftests/resctrl/mbm_test.c | 14 ++++
tools/testing/selftests/resctrl/resctrl.h | 8 +-
tools/testing/selftests/resctrl/resctrl_val.c | 75 ++++---------------
5 files changed, 60 insertions(+), 63 deletions(-)

diff --git a/tools/testing/selftests/resctrl/cmt_test.c b/tools/testing/selftests/resctrl/cmt_test.c
index d8521386cd18..238f514ba7e6 100644
--- a/tools/testing/selftests/resctrl/cmt_test.c
+++ b/tools/testing/selftests/resctrl/cmt_test.c
@@ -16,6 +16,17 @@
#define MAX_DIFF 2000000
#define MAX_DIFF_PERCENT 15

+#define CON_MON_LCC_OCCUP_PATH \
+ "%s/%s/mon_groups/%s/mon_data/mon_L3_%02d/llc_occupancy"
+
+static int cmt_init(const struct resctrl_val_param *param, int domain_id)
+{
+ sprintf(llc_occup_path, CON_MON_LCC_OCCUP_PATH, RESCTRL_PATH,
+ param->ctrlgrp, param->mongrp, domain_id);
+
+ return 0;
+}
+
static int cmt_setup(const struct resctrl_test *test,
const struct user_params *uparams,
struct resctrl_val_param *p)
@@ -139,6 +150,7 @@ static int cmt_run_test(const struct resctrl_test *test, const struct user_param
.filename = RESULT_FILE_NAME,
.mask = ~(long_mask << n) & long_mask,
.num_of_runs = 0,
+ .init = cmt_init,
.setup = cmt_setup,
.measure = cmt_measure,
};
diff --git a/tools/testing/selftests/resctrl/mba_test.c b/tools/testing/selftests/resctrl/mba_test.c
index de6e29faf214..0a95c42f1616 100644
--- a/tools/testing/selftests/resctrl/mba_test.c
+++ b/tools/testing/selftests/resctrl/mba_test.c
@@ -17,6 +17,19 @@
#define ALLOCATION_MIN 10
#define ALLOCATION_STEP 10

+static int mba_init(const struct resctrl_val_param *param, int domain_id)
+{
+ int ret;
+
+ ret = initialize_mem_bw_imc();
+ if (ret)
+ return ret;
+
+ initialize_mem_bw_resctrl(param, domain_id);
+
+ return 0;
+}
+
/*
* Change schemata percentage from 100 to 10%. Write schemata to specified
* con_mon grp, mon_grp in resctrl FS.
@@ -156,6 +169,7 @@ static int mba_run_test(const struct resctrl_test *test, const struct user_param
.mongrp = "m1",
.filename = RESULT_FILE_NAME,
.bw_report = "reads",
+ .init = mba_init,
.setup = mba_setup,
.measure = mba_measure,
};
diff --git a/tools/testing/selftests/resctrl/mbm_test.c b/tools/testing/selftests/resctrl/mbm_test.c
index 59e26adf60bb..00e60b01188a 100644
--- a/tools/testing/selftests/resctrl/mbm_test.c
+++ b/tools/testing/selftests/resctrl/mbm_test.c
@@ -86,6 +86,19 @@ static int check_results(size_t span)
return ret;
}

+static int mbm_init(const struct resctrl_val_param *param, int domain_id)
+{
+ int ret;
+
+ ret = initialize_mem_bw_imc();
+ if (ret)
+ return ret;
+
+ initialize_mem_bw_resctrl(param, domain_id);
+
+ return 0;
+}
+
static int mbm_setup(const struct resctrl_test *test,
const struct user_params *uparams,
struct resctrl_val_param *p)
@@ -123,6 +136,7 @@ static int mbm_run_test(const struct resctrl_test *test, const struct user_param
.ctrlgrp = "c1",
.filename = RESULT_FILE_NAME,
.bw_report = "reads",
+ .init = mbm_init,
.setup = mbm_setup,
.measure = mbm_measure,
};
diff --git a/tools/testing/selftests/resctrl/resctrl.h b/tools/testing/selftests/resctrl/resctrl.h
index 5dc3def70669..d3fbb957309d 100644
--- a/tools/testing/selftests/resctrl/resctrl.h
+++ b/tools/testing/selftests/resctrl/resctrl.h
@@ -86,7 +86,8 @@ struct resctrl_test {
* @mongrp: Name of the monitor group (mon grp)
* @filename: Name of file to which the o/p should be written
* @bw_report: Bandwidth report type (reads vs writes)
- * @setup: Call back function to setup test environment
+ * @init: Callback function to initialize test environment
+ * @setup: Callback function to setup per test run environment
* @measure: Callback that performs the measurement (a single test)
*/
struct resctrl_val_param {
@@ -97,6 +98,8 @@ struct resctrl_val_param {
char *bw_report;
unsigned long mask;
int num_of_runs;
+ int (*init)(const struct resctrl_val_param *param,
+ int domain_id);
int (*setup)(const struct resctrl_test *test,
const struct user_params *uparams,
struct resctrl_val_param *param);
@@ -149,8 +152,11 @@ unsigned char *alloc_buffer(size_t buf_size, int memflush);
void mem_flush(unsigned char *buf, size_t buf_size);
void fill_cache_read(unsigned char *buf, size_t buf_size, bool once);
int run_fill_buf(size_t buf_size, int memflush, int op, bool once);
+int initialize_mem_bw_imc(void);
int measure_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,
+ int domain_id);
int resctrl_val(const struct resctrl_test *test,
const struct user_params *uparams,
const char * const *benchmark_cmd,
diff --git a/tools/testing/selftests/resctrl/resctrl_val.c b/tools/testing/selftests/resctrl/resctrl_val.c
index 47d58c9aed28..164f57454cb0 100644
--- a/tools/testing/selftests/resctrl/resctrl_val.c
+++ b/tools/testing/selftests/resctrl/resctrl_val.c
@@ -23,18 +23,6 @@
#define CON_MBM_LOCAL_BYTES_PATH \
"%s/%s/mon_data/mon_L3_%02d/mbm_local_bytes"

-#define CON_MON_LCC_OCCUP_PATH \
- "%s/%s/mon_groups/%s/mon_data/mon_L3_%02d/llc_occupancy"
-
-#define CON_LCC_OCCUP_PATH \
- "%s/%s/mon_data/mon_L3_%02d/llc_occupancy"
-
-#define MON_LCC_OCCUP_PATH \
- "%s/mon_groups/%s/mon_data/mon_L3_%02d/llc_occupancy"
-
-#define LCC_OCCUP_PATH \
- "%s/mon_data/mon_L3_%02d/llc_occupancy"
-
struct membw_read_format {
__u64 value; /* The value of the event */
__u64 time_enabled; /* if PERF_FORMAT_TOTAL_TIME_ENABLED */
@@ -268,7 +256,7 @@ static int num_of_imcs(void)
return count;
}

-static int initialize_mem_bw_imc(void)
+int initialize_mem_bw_imc(void)
{
int imc, j;

@@ -430,24 +418,18 @@ static int get_mem_bw_imc(char *bw_report, float *bw_imc)

/*
* initialize_mem_bw_resctrl: Appropriately populate "mbm_total_path"
- * @ctrlgrp: Name of the control monitor group (con_mon grp)
- * @domain_id: Domain ID (cache ID; for MB, L3 cache ID)
+ * @param: Parameters passed to resctrl_val()
+ * @domain_id: Domain ID (cache ID; for MB, L3 cache ID)
*/
-static void initialize_mem_bw_resctrl(const char *ctrlgrp, int domain_id)
+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,
- ctrlgrp, domain_id);
+ param->ctrlgrp, domain_id);
}

/*
- * Get MBM Local bytes as reported by resctrl FS
- * For MBM,
- * 1. If con_mon grp and mon grp are given, then read from con_mon grp's mon grp
- * 2. If only con_mon grp is given, then read from con_mon grp
- * 3. If both are not given, then read from root con_mon grp
- * For MBA,
- * 1. If con_mon grp is given, then read from it
- * 2. If con_mon grp is not given, then read from root con_mon grp
+ * Open file to read MBM local bytes from resctrl FS
*/
static FILE *open_mem_bw_resctrl(const char *mbm_bw_file)
{
@@ -460,6 +442,9 @@ static FILE *open_mem_bw_resctrl(const char *mbm_bw_file)
return fp;
}

+/*
+ * Get MBM Local bytes as reported by resctrl FS
+ */
static int get_mem_bw_resctrl(FILE *fp, unsigned long *mbm_total)
{
if (fscanf(fp, "%lu\n", mbm_total) <= 0) {
@@ -572,35 +557,6 @@ static int print_results_bw(char *filename, pid_t bm_pid, float bw_imc,
return 0;
}

-static void set_cmt_path(const char *ctrlgrp, const char *mongrp, char sock_num)
-{
- if (strlen(ctrlgrp) && strlen(mongrp))
- sprintf(llc_occup_path, CON_MON_LCC_OCCUP_PATH, RESCTRL_PATH,
- ctrlgrp, mongrp, sock_num);
- else if (!strlen(ctrlgrp) && strlen(mongrp))
- sprintf(llc_occup_path, MON_LCC_OCCUP_PATH, RESCTRL_PATH,
- mongrp, sock_num);
- else if (strlen(ctrlgrp) && !strlen(mongrp))
- sprintf(llc_occup_path, CON_LCC_OCCUP_PATH, RESCTRL_PATH,
- ctrlgrp, sock_num);
- else if (!strlen(ctrlgrp) && !strlen(mongrp))
- sprintf(llc_occup_path, LCC_OCCUP_PATH, RESCTRL_PATH, sock_num);
-}
-
-/*
- * initialize_llc_occu_resctrl: Appropriately populate "llc_occup_path"
- * @ctrlgrp: Name of the control monitor group (con_mon grp)
- * @mongrp: Name of the monitor group (mon grp)
- * @domain_id: Domain ID (cache ID; for MB, L3 cache ID)
- * @resctrl_val: Resctrl feature (Eg: cat, cmt.. etc)
- */
-static void initialize_llc_occu_resctrl(const char *ctrlgrp, const char *mongrp,
- int domain_id, char *resctrl_val)
-{
- if (!strncmp(resctrl_val, CMT_STR, sizeof(CMT_STR)))
- set_cmt_path(ctrlgrp, mongrp, domain_id);
-}
-
/*
* measure_mem_bw - Measures memory bandwidth numbers while benchmark runs
* @uparams: User supplied parameters
@@ -830,16 +786,11 @@ int resctrl_val(const struct resctrl_test *test,
if (ret)
goto out;

- if (!strncmp(resctrl_val, MBM_STR, sizeof(MBM_STR)) ||
- !strncmp(resctrl_val, MBA_STR, sizeof(MBA_STR))) {
- ret = initialize_mem_bw_imc();
+ if (param->init) {
+ ret = param->init(param, domain_id);
if (ret)
goto out;
-
- initialize_mem_bw_resctrl(param->ctrlgrp, domain_id);
- } else if (!strncmp(resctrl_val, CMT_STR, sizeof(CMT_STR)))
- initialize_llc_occu_resctrl(param->ctrlgrp, param->mongrp,
- domain_id, resctrl_val);
+ }

/* Parent waits for child to be ready. */
close(pipefd[1]);
--
2.39.2


2024-05-31 18:17:30

by Reinette Chatre

[permalink] [raw]
Subject: Re: [PATCH v5 02/16] selftests/resctrl: Calculate resctrl FS derived mem bw over sleep(1) only

Hi Ilpo,

On 5/31/24 6:11 AM, Ilpo Järvinen wrote:
> For MBM/MBA tests, measure_vals() calls get_mem_bw_imc() that performs
> the measurement over a duration of sleep(1) call. The memory bandwidth
> numbers from IMC are derived over this duration. The resctrl FS derived
> memory bandwidth, however, is calculated inside measure_vals() and only
> takes delta between the previous value and the current one which
> besides the actual test, also samples inter-test noise.
>
> Rework the logic in measure_vals() and get_mem_bw_imc() such that the
> resctrl FS memory bandwidth section covers much shorter duration
> closely matching that of the IMC perf counters to improve measurement
> accuracy.
>
> For the second read after rewind() to return a fresh value, also
> newline has to be consumed by the fscanf().
>
> Suggested-by: Reinette Chatre <[email protected]>
> Signed-off-by: Ilpo Järvinen <[email protected]>
> ---
>
> v5:
> - Open mem bw file once and use rewind()
> - Read \n from the mem bw file to allow rewind to return a new value.
> v4:
> - Open resctrl mem bw file (twice) beforehand to avoid opening it during
> the test
> v3:
> - Don't drop Return: entry from perf_open_imc_mem_bw() func comment
> ---
> tools/testing/selftests/resctrl/resctrl_val.c | 115 ++++++++++++------
> 1 file changed, 80 insertions(+), 35 deletions(-)
>
> diff --git a/tools/testing/selftests/resctrl/resctrl_val.c b/tools/testing/selftests/resctrl/resctrl_val.c
> index f55f5989de72..6231275a6e6c 100644
> --- a/tools/testing/selftests/resctrl/resctrl_val.c
> +++ b/tools/testing/selftests/resctrl/resctrl_val.c
> @@ -306,18 +306,13 @@ static void perf_close_imc_mem_bw(void)
> }
>
> /*
> - * get_mem_bw_imc: Memory band width as reported by iMC counters
> - * @cpu_no: CPU number that the benchmark PID is binded to
> - * @bw_report: Bandwidth report type (reads, writes)
> - *
> - * Memory B/W utilized by a process on a socket can be calculated using
> - * iMC counters. Perf events are used to read these counters.
> + * perf_open_imc_mem_bw - Open perf fds for IMCs
> + * @cpu_no: CPU number that the benchmark PID is binded to

"is binded to" -> "is bound to"?

> *
> * Return: = 0 on success. < 0 on failure.
> */
> -static int get_mem_bw_imc(int cpu_no, char *bw_report, float *bw_imc)
> +static int perf_open_imc_mem_bw(int cpu_no)
> {
> - float reads, writes, of_mul_read, of_mul_write;
> int imc, ret;
>
> for (imc = 0; imc < imcs; imc++) {
> @@ -325,8 +320,6 @@ static int get_mem_bw_imc(int cpu_no, char *bw_report, float *bw_imc)
> imc_counters_config[imc][WRITE].fd = -1;
> }
>
> - /* Start all iMC counters to log values (both read and write) */
> - reads = 0, writes = 0, of_mul_read = 1, of_mul_write = 1;
> for (imc = 0; imc < imcs; imc++) {
> ret = open_perf_event(imc, cpu_no, READ);
> if (ret)
> @@ -334,7 +327,26 @@ static int get_mem_bw_imc(int cpu_no, char *bw_report, float *bw_imc)
> ret = open_perf_event(imc, cpu_no, WRITE);
> if (ret)
> goto close_fds;
> + }
> +
> + return 0;
> +
> +close_fds:
> + perf_close_imc_mem_bw();
> + return -1;
> +}
>
> +/*
> + * do_mem_bw_test - Perform memory bandwidth test
> + *
> + * Runs memory bandwidth test over one second period. Also, handles starting
> + * and stopping of the IMC perf counters around the test.
> + */
> +static void do_imc_mem_bw_test(void)
> +{
> + int imc;
> +
> + for (imc = 0; imc < imcs; imc++) {
> membw_ioctl_perf_event_ioc_reset_enable(imc, READ);
> membw_ioctl_perf_event_ioc_reset_enable(imc, WRITE);
> }
> @@ -346,6 +358,24 @@ static int get_mem_bw_imc(int cpu_no, char *bw_report, float *bw_imc)
> membw_ioctl_perf_event_ioc_disable(imc, READ);
> membw_ioctl_perf_event_ioc_disable(imc, WRITE);
> }
> +}
> +
> +/*
> + * get_mem_bw_imc - Memory band width as reported by iMC counters
> + * @bw_report: Bandwidth report type (reads, writes)
> + *
> + * Memory B/W utilized by a process on a socket can be calculated using
> + * iMC counters. Perf events are used to read these counters.
> + *
> + * Return: = 0 on success. < 0 on failure.
> + */
> +static int get_mem_bw_imc(char *bw_report, float *bw_imc)
> +{
> + float reads, writes, of_mul_read, of_mul_write;
> + int imc;
> +
> + /* Start all iMC counters to log values (both read and write) */
> + reads = 0, writes = 0, of_mul_read = 1, of_mul_write = 1;
>
> /*
> * Get results which are stored in struct type imc_counter_config
> @@ -462,24 +492,23 @@ static void initialize_mem_bw_resctrl(const char *ctrlgrp, const char *mongrp,
> * 1. If con_mon grp is given, then read from it
> * 2. If con_mon grp is not given, then read from root con_mon grp
> */
> -static int get_mem_bw_resctrl(unsigned long *mbm_total)
> +static FILE *open_mem_bw_resctrl(const char *mbm_bw_file)
> {
> FILE *fp;
>
> - fp = fopen(mbm_total_path, "r");
> - if (!fp) {
> + fp = fopen(mbm_bw_file, "r");
> + if (!fp)
> ksft_perror("Failed to open total bw file");
>
> - return -1;
> - }
> - if (fscanf(fp, "%lu", mbm_total) <= 0) {
> - ksft_perror("Could not get mbm local bytes");
> - fclose(fp);
> + return fp;
> +}
>
> +static int get_mem_bw_resctrl(FILE *fp, unsigned long *mbm_total)
> +{
> + if (fscanf(fp, "%lu\n", mbm_total) <= 0) {
> + ksft_perror("Could not get mbm local bytes");

I understand that you just copied this, but could you please
change "mbm" to "MBM" during this copy?

> return -1;
> }
> - fclose(fp);
> -
> return 0;
> }
>
> @@ -616,13 +645,17 @@ static void initialize_llc_occu_resctrl(const char *ctrlgrp, const char *mongrp,
> }
>
> static int measure_vals(const struct user_params *uparams,
> - struct resctrl_val_param *param,
> - unsigned long *bw_resc_start)
> + struct resctrl_val_param *param)
> {
> - unsigned long bw_resc, bw_resc_end;
> + unsigned long bw_resc, bw_resc_start, bw_resc_end;
> + FILE *mem_bw_fp;
> float bw_imc;
> int ret;
>
> + mem_bw_fp = open_mem_bw_resctrl(mbm_total_path);
> + if (!mem_bw_fp)
> + return -1;
> +

The comment below seems to refer to the resctrl measurement
that starts with the above snippet. Any reason why this snippet
is above the comment that follows since the comment seems to
apply to it?

> /*
> * Measure memory bandwidth from resctrl and from
> * another source which is perf imc value or could
> @@ -630,22 +663,35 @@ static int measure_vals(const struct user_params *uparams,
> * Compare the two values to validate resctrl value.
> * It takes 1sec to measure the data.
> */
> - ret = get_mem_bw_imc(uparams->cpu, param->bw_report, &bw_imc);
> + ret = perf_open_imc_mem_bw(uparams->cpu);
> if (ret < 0)
> - return ret;
> + goto close_fp;
>
> - ret = get_mem_bw_resctrl(&bw_resc_end);
> + ret = get_mem_bw_resctrl(mem_bw_fp, &bw_resc_start);
> if (ret < 0)
> - return ret;
> + goto close_fp;

perf_close_imc_mem_bw() seems to be missing from error path?

Symmetrical code is easier to understand. Looks like
perf_close_imc_mem_bw() stayed behind in get_mem_bw_imc() but I think
it would make things easier if get_mem_bw_imc() no longer calls
perf_close_imc_mem_bw() but instead leave that to the one that
calls perf_open_imc_mem_bw().

>
> - bw_resc = (bw_resc_end - *bw_resc_start) / MB;
> - ret = print_results_bw(param->filename, bm_pid, bw_imc, bw_resc);
> - if (ret)
> - return ret;
> + rewind(mem_bw_fp);
>
> - *bw_resc_start = bw_resc_end;
> + do_imc_mem_bw_test();
>
> - return 0;
> + ret = get_mem_bw_resctrl(mem_bw_fp, &bw_resc_end);
> + if (ret < 0)
> + goto close_fp;
> +
> + ret = get_mem_bw_imc(param->bw_report, &bw_imc);
> + if (ret < 0)
> + goto close_fp;
> +
> + fclose(mem_bw_fp);
> +
> + bw_resc = (bw_resc_end - bw_resc_start) / MB;
> +
> + return print_results_bw(param->filename, bm_pid, bw_imc, bw_resc);
> +
> +close_fp:
> + fclose(mem_bw_fp);
> + return ret;
> }
>
> /*
> @@ -719,7 +765,6 @@ int resctrl_val(const struct resctrl_test *test,
> struct resctrl_val_param *param)
> {
> char *resctrl_val = param->resctrl_val;
> - unsigned long bw_resc_start = 0;
> struct sigaction sigact;
> int ret = 0, pipefd[2];
> char pipe_message = 0;
> @@ -861,7 +906,7 @@ int resctrl_val(const struct resctrl_test *test,
>
> if (!strncmp(resctrl_val, MBM_STR, sizeof(MBM_STR)) ||
> !strncmp(resctrl_val, MBA_STR, sizeof(MBA_STR))) {
> - ret = measure_vals(uparams, param, &bw_resc_start);
> + ret = measure_vals(uparams, param);
> if (ret)
> break;
> } else if (!strncmp(resctrl_val, CMT_STR, sizeof(CMT_STR))) {

Reinette

2024-05-31 18:18:00

by Reinette Chatre

[permalink] [raw]
Subject: Re: [PATCH v5 05/16] selftests/resctrl: Use correct type for pids

Hi Ilpo,

On 5/31/24 6:11 AM, Ilpo Järvinen wrote:
> A few functions receive PIDs through int arguments. PIDs variables
> should be of type pid_t, not int.
>
> Convert pid arguments from int to pid_t.
>
> Before printing PID, match the type to %d by casting to int which is
> enough for Linux (standard would allow using a longer integer type but
> generalizing for that would complicate the code unnecessarily, the
> selftest code does not need to be portable).
>
> Signed-off-by: Ilpo Järvinen <[email protected]>
> ---

Thank you.

Reviewed-by: Reinette Chatre <[email protected]>

Reinette

2024-05-31 18:18:49

by Reinette Chatre

[permalink] [raw]
Subject: Re: [PATCH v5 13/16] selftests/resctrl: Convert ctrlgrp & mongrp to pointers

Hi Ilpo,

On 5/31/24 6:11 AM, Ilpo Järvinen wrote:
> The struct resctrl_val_param has control and monitor groups as char
> arrays but they are not supposed to be mutated within resctrl_val().
>
> Convert the ctrlgrp and mongrp char array within resctrl_val_param to
> plain const char pointers and adjust the strlen() based checks to
> check NULL instead.
>
> Convert !grp_name check in create_grp() into internal sanity check by
> returning error if the caller asked to create a group but doesn't
> provide a name for the group. The existing code already abides this by
> only calling create_grp() if mongrp is non-NULL so the error should
> never be returned with the current selftests (ctrlgrp is never NULL).

This paragraph is no longer relevant and can be dropped.

>
> Signed-off-by: Ilpo Järvinen <[email protected]>
> ---
> v5:
> - Return 0 if grp_name is null (restore earlier behavior)
> - Move the root group note from comment into kerneldoc
>
> v3:
> - Removed wrong comment
> - Changed grp_name check to return -1 on fail (internal sanity check)
> ---
> tools/testing/selftests/resctrl/resctrl.h | 4 ++--
> tools/testing/selftests/resctrl/resctrlfs.c | 16 +++++++---------
> 2 files changed, 9 insertions(+), 11 deletions(-)
>
> diff --git a/tools/testing/selftests/resctrl/resctrl.h b/tools/testing/selftests/resctrl/resctrl.h
> index 5967389038d4..a999fbc13fd3 100644
> --- a/tools/testing/selftests/resctrl/resctrl.h
> +++ b/tools/testing/selftests/resctrl/resctrl.h
> @@ -91,8 +91,8 @@ struct resctrl_test {
> */
> struct resctrl_val_param {
> char *resctrl_val;
> - char ctrlgrp[64];
> - char mongrp[64];
> + const char *ctrlgrp;
> + const char *mongrp;
> char filename[64];
> unsigned long mask;
> int num_of_runs;
> diff --git a/tools/testing/selftests/resctrl/resctrlfs.c b/tools/testing/selftests/resctrl/resctrlfs.c
> index f4dc8ef23a8c..893041faaf18 100644
> --- a/tools/testing/selftests/resctrl/resctrlfs.c
> +++ b/tools/testing/selftests/resctrl/resctrlfs.c
> @@ -456,6 +456,9 @@ int taskset_restore(pid_t bm_pid, cpu_set_t *old_affinity)
> * @grp: Full path and name of the group
> * @parent_grp: Full path and name of the parent group
> *
> + * Creates a group @grp_name if it does not exist yet. If @grp_name is NULL,
> + * it is interpreted as the root group which always results success.

"always results success" -> "always results in success"?

With changelog and comment fixups addressed:
| Reviewed-by: Reinette Chatre <[email protected]>

Reinette

2024-05-31 18:18:57

by Reinette Chatre

[permalink] [raw]
Subject: Re: [PATCH v5 16/16] selftests/resctrl: Remove test name comparing from write_bm_pid_to_resctrl()

Hi Ilpo,

On 5/31/24 6:11 AM, Ilpo Järvinen wrote:
> write_bm_pid_to_resctrl() uses resctrl_val to check test name which is
> not a good interface generic resctrl FS functions should provide.
>
> Tests define mongrp when needed. Remove the test name check in
> write_bm_pid_to_resctrl() to only rely on the mongrp parameter being
> non-NULL.
>
> Remove write_bm_pid_to_resctrl() resctrl_val parameter and resctrl_val
> member from the struct resctrl_val_param that are not used anymore.
> Similarly, remove the test name constants that are no longer used.
>
> Signed-off-by: Ilpo Järvinen <[email protected]>
> ---

Thank you.

Reviewed-by: Reinette Chatre <[email protected]>

Reinette

2024-06-03 08:26:15

by Ilpo Järvinen

[permalink] [raw]
Subject: Re: [PATCH v5 02/16] selftests/resctrl: Calculate resctrl FS derived mem bw over sleep(1) only

On Fri, 31 May 2024, Reinette Chatre wrote:
> On 5/31/24 6:11 AM, Ilpo J?rvinen wrote:
> > For MBM/MBA tests, measure_vals() calls get_mem_bw_imc() that performs
> > the measurement over a duration of sleep(1) call. The memory bandwidth
> > numbers from IMC are derived over this duration. The resctrl FS derived
> > memory bandwidth, however, is calculated inside measure_vals() and only
> > takes delta between the previous value and the current one which
> > besides the actual test, also samples inter-test noise.
> >
> > Rework the logic in measure_vals() and get_mem_bw_imc() such that the
> > resctrl FS memory bandwidth section covers much shorter duration
> > closely matching that of the IMC perf counters to improve measurement
> > accuracy.
> >
> > For the second read after rewind() to return a fresh value, also
> > newline has to be consumed by the fscanf().
> >
> > Suggested-by: Reinette Chatre <[email protected]>
> > Signed-off-by: Ilpo J?rvinen <[email protected]>
> > ---
> >
> > v5:
> > - Open mem bw file once and use rewind()
> > - Read \n from the mem bw file to allow rewind to return a new value.
> > v4:
> > - Open resctrl mem bw file (twice) beforehand to avoid opening it during
> > the test
> > v3:
> > - Don't drop Return: entry from perf_open_imc_mem_bw() func comment
> > ---
> > tools/testing/selftests/resctrl/resctrl_val.c | 115 ++++++++++++------
> > 1 file changed, 80 insertions(+), 35 deletions(-)
> >
> > diff --git a/tools/testing/selftests/resctrl/resctrl_val.c
> > b/tools/testing/selftests/resctrl/resctrl_val.c
> > index f55f5989de72..6231275a6e6c 100644
> > --- a/tools/testing/selftests/resctrl/resctrl_val.c
> > +++ b/tools/testing/selftests/resctrl/resctrl_val.c

> > @@ -616,13 +645,17 @@ static void initialize_llc_occu_resctrl(const char
> > *ctrlgrp, const char *mongrp,
> > }
> > static int measure_vals(const struct user_params *uparams,
> > - struct resctrl_val_param *param,
> > - unsigned long *bw_resc_start)
> > + struct resctrl_val_param *param)
> > {
> > - unsigned long bw_resc, bw_resc_end;
> > + unsigned long bw_resc, bw_resc_start, bw_resc_end;
> > + FILE *mem_bw_fp;
> > float bw_imc;
> > int ret;
> > + mem_bw_fp = open_mem_bw_resctrl(mbm_total_path);
> > + if (!mem_bw_fp)
> > + return -1;
> > +
>
> The comment below seems to refer to the resctrl measurement
> that starts with the above snippet. Any reason why this snippet
> is above the comment that follows since the comment seems to
> apply to it?

No particular reason. I've made the comment a function one now which
seemed better placement for it.

> > /*
> > * Measure memory bandwidth from resctrl and from
> > * another source which is perf imc value or could

> > @@ -630,22 +663,35 @@ static int measure_vals(const struct user_params
> > *uparams,
> > * Compare the two values to validate resctrl value.
> > * It takes 1sec to measure the data.
> > */
> > - ret = get_mem_bw_imc(uparams->cpu, param->bw_report, &bw_imc);
> > + ret = perf_open_imc_mem_bw(uparams->cpu);
> > if (ret < 0)
> > - return ret;
> > + goto close_fp;
> > - ret = get_mem_bw_resctrl(&bw_resc_end);
> > + ret = get_mem_bw_resctrl(mem_bw_fp, &bw_resc_start);
> > if (ret < 0)
> > - return ret;
> > + goto close_fp;
>
> perf_close_imc_mem_bw() seems to be missing from error path?
>
> Symmetrical code is easier to understand. Looks like
> perf_close_imc_mem_bw() stayed behind in get_mem_bw_imc() but I think
> it would make things easier if get_mem_bw_imc() no longer calls
> perf_close_imc_mem_bw() but instead leave that to the one that
> calls perf_open_imc_mem_bw().

Okay yeah, it makes things more tractable.

--
i.

2024-06-03 11:39:34

by Ilpo Järvinen

[permalink] [raw]
Subject: Re: [PATCH v5 13/16] selftests/resctrl: Convert ctrlgrp & mongrp to pointers

On Fri, 31 May 2024, Reinette Chatre wrote:
> On 5/31/24 6:11 AM, Ilpo Järvinen wrote:
> > The struct resctrl_val_param has control and monitor groups as char
> > arrays but they are not supposed to be mutated within resctrl_val().
> >
> > Convert the ctrlgrp and mongrp char array within resctrl_val_param to
> > plain const char pointers and adjust the strlen() based checks to
> > check NULL instead.
> >
> > Convert !grp_name check in create_grp() into internal sanity check by
> > returning error if the caller asked to create a group but doesn't
> > provide a name for the group. The existing code already abides this by
> > only calling create_grp() if mongrp is non-NULL so the error should
> > never be returned with the current selftests (ctrlgrp is never NULL).
>
> This paragraph is no longer relevant and can be dropped.

Thanks for catching this. I'm absolutely sure I had this open one in
my editor and removed it but it seems I did not, no idea what happened.

--
i.

2024-06-06 00:54:21

by Moger, Babu

[permalink] [raw]
Subject: Re: [PATCH v5 00/16] selftests/resctrl: resctrl_val() related cleanups & improvements

Tested the series.

Tested-by: Babu Moger <[email protected]>


On 5/31/2024 8:11 AM, Ilpo Järvinen wrote:
> Hi all,
>
> This series does a number of cleanups into resctrl_val() and
> generalizes it by removing test name specific handling from the
> function.
>
> Hopefully these reach also Shuah successfully as I've recently seen
> rejects for mail from @linux.intel.com to gmail addresses.
>
> v5:
> - Open mem bw file only once and use rewind().
> - Add \n to mem bw file read to allow reading fresh values from the file.
> - Return 0 if create_grp() is given NULL grp_name (matches the original
> behavior). Mention this in function's kerneldoc.
> - Cast pid_t to int before printing with %d.
> - Caps/typo fixes to kerneldoc and commit messages.
> - Use imperative tone in commit messages and improve them based on points
> that came up during review.
>
> v4:
> - Merged close fix into IMC READ+WRITE rework patch
> - Add loop to reset imc_counters_config fds to -1 to be able know which
> need closing
> - Introduce perf_close_imc_mem_bw() to close fds
> - Open resctrl mem bw file (twice) beforehand to avoid opening it during
> the test
> - Remove MBM .mongrp setup
> - Remove mongrp from CMT test
>
> v3:
> - Rename init functions to <testname>_init()
> - Replace for loops with READ+WRITE statements for clarity
> - Don't drop Return: entry from perf_open_imc_mem_bw() func comment
> - New patch: Fix closing of IMC fds in case of error
> - New patch: Make "bandwidth" consistent in comments & prints
> - New patch: Simplify mem bandwidth file code
> - Remove wrong comment
> - Changed grp_name check to return -1 on fail (internal sanity check)
>
> v2:
> - Resolved conflicts with kselftest/next
> - Spaces -> tabs correction
>
> Ilpo Järvinen (16):
> selftests/resctrl: Fix closing IMC fds on error and open-code R+W
> instead of loops
> selftests/resctrl: Calculate resctrl FS derived mem bw over sleep(1)
> only
> selftests/resctrl: Make "bandwidth" consistent in comments & prints
> selftests/resctrl: Consolidate get_domain_id() into resctrl_val()
> selftests/resctrl: Use correct type for pids
> selftests/resctrl: Cleanup bm_pid and ppid usage & limit scope
> selftests/resctrl: Rename measure_vals() to measure_mem_bw_vals() &
> document
> selftests/resctrl: Simplify mem bandwidth file code for MBA & MBM
> tests
> selftests/resctrl: Add ->measure() callback to resctrl_val_param
> selftests/resctrl: Add ->init() callback into resctrl_val_param
> selftests/resctrl: Simplify bandwidth report type handling
> selftests/resctrl: Make some strings passed to resctrlfs functions
> const
> selftests/resctrl: Convert ctrlgrp & mongrp to pointers
> selftests/resctrl: Remove mongrp from MBA test
> selftests/resctrl: Remove mongrp from CMT test
> selftests/resctrl: Remove test name comparing from
> write_bm_pid_to_resctrl()
>
> tools/testing/selftests/resctrl/cache.c | 10 +-
> tools/testing/selftests/resctrl/cat_test.c | 5 +-
> tools/testing/selftests/resctrl/cmt_test.c | 22 +-
> tools/testing/selftests/resctrl/mba_test.c | 26 +-
> tools/testing/selftests/resctrl/mbm_test.c | 26 +-
> tools/testing/selftests/resctrl/resctrl.h | 49 ++-
> tools/testing/selftests/resctrl/resctrl_val.c | 364 ++++++++----------
> tools/testing/selftests/resctrl/resctrlfs.c | 67 ++--
> 8 files changed, 290 insertions(+), 279 deletions(-)
>

--
- Babu Moger