[GIT PULL] cpupower update for Linux 6.4-rc3

[Shuah Khan]

Hi Rafael,

Please pull the following cpupower update for Linux 6.4-rc3 or for
a later rc.

This cpupower fixes update for Linux 6.4-rc3 consists of:

- a resource leak fix
- fix drift in C0 percentage calculation due to System-wide TSC read.
  To lower this drift read TSC per CPU and also just after mperf read.
  This technique improves C0 percentage calculation in Mperf monitor

diff is attached.

thanks,
-- Shuah

----------------------------------------------------------------
The following changes since commit ac9a78681b921877518763ba0e89202254349d1b:

  Linux 6.4-rc1 (2023-05-07 13:34:35 -0700)

are available in the Git repository at:

  git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux tags/linux-cpupower-6.4-rc3

for you to fetch changes up to c2adb1877b76fc81ae041e1db1a6ed2078c6746b:

  cpupower: Make TSC read per CPU for Mperf monitor (2023-05-08 10:46:49 -0600)

----------------------------------------------------------------
linux-cpupower-6.4-rc3

This cpupower fixes update for Linux 6.4-rc3 consists of:

- a resource leak fix
- fix drift in C0 percentage calculation due to System-wide TSC read.
  To lower this drift read TSC per CPU and also just after mperf read.
  This technique improves C0 percentage calculation in Mperf monitor

----------------------------------------------------------------
Hao Zeng (1):
      cpupower:Fix resource leaks in sysfs_get_enabled()

Wyes Karny (1):
      cpupower: Make TSC read per CPU for Mperf monitor

 tools/power/cpupower/lib/powercap.c                | 23 +++++++++++-----
 .../cpupower/utils/idle_monitor/mperf_monitor.c    | 31 ++++++++++------------
 2 files changed, 30 insertions(+), 24 deletions(-)

----------------------------------------------------------------diff --git a/tools/power/cpupower/lib/powercap.c b/tools/power/cpupower/lib/powercap.c
index 0ce29ee4c2e4..a7a59c6bacda 100644
--- a/tools/power/cpupower/lib/powercap.c
+++ b/tools/power/cpupower/lib/powercap.c
@@ -40,25 +40,34 @@ static int sysfs_get_enabled(char *path, int *mode)
 {
 	int fd;
 	char yes_no;
+	int ret = 0;
 
 	*mode = 0;
 
 	fd = open(path, O_RDONLY);
-	if (fd == -1)
-		return -1;
+	if (fd == -1) {
+		ret = -1;
+		goto out;
+	}
 
 	if (read(fd, &yes_no, 1) != 1) {
-		close(fd);
-		return -1;
+		ret = -1;
+		goto out_close;
 	}
 
 	if (yes_no == '1') {
 		*mode = 1;
-		return 0;
+		goto out_close;
 	} else if (yes_no == '0') {
-		return 0;
+		goto out_close;
+	} else {
+		ret = -1;
+		goto out_close;
 	}
-	return -1;
+out_close:
+	close(fd);
+out:
+	return ret;
 }
 
 int powercap_get_enabled(int *mode)
diff --git a/tools/power/cpupower/utils/idle_monitor/mperf_monitor.c b/tools/power/cpupower/utils/idle_monitor/mperf_monitor.c
index e7d48cb563c0..ae6af354a81d 100644
--- a/tools/power/cpupower/utils/idle_monitor/mperf_monitor.c
+++ b/tools/power/cpupower/utils/idle_monitor/mperf_monitor.c
@@ -70,8 +70,8 @@ static int max_freq_mode;
  */
 static unsigned long max_frequency;
 
-static unsigned long long tsc_at_measure_start;
-static unsigned long long tsc_at_measure_end;
+static unsigned long long *tsc_at_measure_start;
+static unsigned long long *tsc_at_measure_end;
 static unsigned long long *mperf_previous_count;
 static unsigned long long *aperf_previous_count;
 static unsigned long long *mperf_current_count;
@@ -169,7 +169,7 @@ static int mperf_get_count_percent(unsigned int id, double *percent,
 	aperf_diff = aperf_current_count[cpu] - aperf_previous_count[cpu];
 
 	if (max_freq_mode == MAX_FREQ_TSC_REF) {
-		tsc_diff = tsc_at_measure_end - tsc_at_measure_start;
+		tsc_diff = tsc_at_measure_end[cpu] - tsc_at_measure_start[cpu];
 		*percent = 100.0 * mperf_diff / tsc_diff;
 		dprint("%s: TSC Ref - mperf_diff: %llu, tsc_diff: %llu\n",
 		       mperf_cstates[id].name, mperf_diff, tsc_diff);
@@ -206,7 +206,7 @@ static int mperf_get_count_freq(unsigned int id, unsigned long long *count,
 
 	if (max_freq_mode == MAX_FREQ_TSC_REF) {
 		/* Calculate max_freq from TSC count */
-		tsc_diff = tsc_at_measure_end - tsc_at_measure_start;
+		tsc_diff = tsc_at_measure_end[cpu] - tsc_at_measure_start[cpu];
 		time_diff = timespec_diff_us(time_start, time_end);
 		max_frequency = tsc_diff / time_diff;
 	}
@@ -225,33 +225,27 @@ static int mperf_get_count_freq(unsigned int id, unsigned long long *count,
 static int mperf_start(void)
 {
 	int cpu;
-	unsigned long long dbg;
 
 	clock_gettime(CLOCK_REALTIME, &time_start);
-	mperf_get_tsc(&tsc_at_measure_start);
 
-	for (cpu = 0; cpu < cpu_count; cpu++)
+	for (cpu = 0; cpu < cpu_count; cpu++) {
+		mperf_get_tsc(&tsc_at_measure_start[cpu]);
 		mperf_init_stats(cpu);
+	}
 
-	mperf_get_tsc(&dbg);
-	dprint("TSC diff: %llu\n", dbg - tsc_at_measure_start);
 	return 0;
 }
 
 static int mperf_stop(void)
 {
-	unsigned long long dbg;
 	int cpu;
 
-	for (cpu = 0; cpu < cpu_count; cpu++)
+	for (cpu = 0; cpu < cpu_count; cpu++) {
 		mperf_measure_stats(cpu);
+		mperf_get_tsc(&tsc_at_measure_end[cpu]);
+	}
 
-	mperf_get_tsc(&tsc_at_measure_end);
 	clock_gettime(CLOCK_REALTIME, &time_end);
-
-	mperf_get_tsc(&dbg);
-	dprint("TSC diff: %llu\n", dbg - tsc_at_measure_end);
-
 	return 0;
 }
 
@@ -353,7 +347,8 @@ struct cpuidle_monitor *mperf_register(void)
 	aperf_previous_count = calloc(cpu_count, sizeof(unsigned long long));
 	mperf_current_count = calloc(cpu_count, sizeof(unsigned long long));
 	aperf_current_count = calloc(cpu_count, sizeof(unsigned long long));
-
+	tsc_at_measure_start = calloc(cpu_count, sizeof(unsigned long long));
+	tsc_at_measure_end = calloc(cpu_count, sizeof(unsigned long long));
 	mperf_monitor.name_len = strlen(mperf_monitor.name);
 	return &mperf_monitor;
 }
@@ -364,6 +359,8 @@ void mperf_unregister(void)
 	free(aperf_previous_count);
 	free(mperf_current_count);
 	free(aperf_current_count);
+	free(tsc_at_measure_start);
+	free(tsc_at_measure_end);
 	free(is_valid);
 }