[PATCH v2 5/8] turbostat: Add a helper to parse a single int out of a file

From: Josh Triplett
Date: Tue Aug 20 2013 - 20:21:01 EST


Many different chunks of code in turbostat open a file, parse a single
int out of it, and close it. Factor that out into a common function.

Signed-off-by: Josh Triplett <josh@xxxxxxxxxxxxxxxx>
---
tools/power/x86/turbostat/turbostat.c | 81 +++++++++++------------------------
1 file changed, 24 insertions(+), 57 deletions(-)

diff --git a/tools/power/x86/turbostat/turbostat.c b/tools/power/x86/turbostat/turbostat.c
index 514adba..e0dbada 100644
--- a/tools/power/x86/turbostat/turbostat.c
+++ b/tools/power/x86/turbostat/turbostat.c
@@ -21,6 +21,7 @@

#define _GNU_SOURCE
#include MSRHEADER
+#include <stdarg.h>
#include <stdio.h>
#include <unistd.h>
#include <sys/types.h>
@@ -1152,27 +1153,38 @@ void free_all_buffers(void)
}

/*
- * cpu_is_first_sibling_in_core(cpu)
- * return 1 if given CPU is 1st HT sibling in the core
+ * Parse a file containing a single int.
*/
-int cpu_is_first_sibling_in_core(int cpu)
+int parse_int_file(const char *fmt, ...)
{
- char path[64];
+ va_list args;
+ char path[PATH_MAX];
FILE *filep;
- int first_cpu;
+ int value;

- sprintf(path, "/sys/devices/system/cpu/cpu%d/topology/thread_siblings_list", cpu);
+ va_start(args, fmt);
+ vsnprintf(path, sizeof(path), fmt, args);
+ va_end(args);
filep = fopen(path, "r");
- if (filep == NULL) {
+ if (!filep) {
perror(path);
exit(1);
}
- if (fscanf(filep, "%d", &first_cpu) != 1) {
+ if (fscanf(filep, "%d", &value) != 1) {
perror(path);
exit(1);
}
fclose(filep);
- return (cpu == first_cpu);
+ return value;
+}
+
+/*
+ * cpu_is_first_sibling_in_core(cpu)
+ * return 1 if given CPU is 1st HT sibling in the core
+ */
+int cpu_is_first_sibling_in_core(int cpu)
+{
+ return cpu == parse_int_file("/sys/devices/system/cpu/cpu%d/topology/thread_siblings_list", cpu);
}

/*
@@ -1181,62 +1193,17 @@ int cpu_is_first_sibling_in_core(int cpu)
*/
int cpu_is_first_core_in_package(int cpu)
{
- char path[64];
- FILE *filep;
- int first_cpu;
-
- sprintf(path, "/sys/devices/system/cpu/cpu%d/topology/core_siblings_list", cpu);
- filep = fopen(path, "r");
- if (filep == NULL) {
- perror(path);
- exit(1);
- }
- if (fscanf(filep, "%d", &first_cpu) != 1) {
- perror(path);
- exit(1);
- }
- fclose(filep);
- return (cpu == first_cpu);
+ return cpu == parse_int_file("/sys/devices/system/cpu/cpu%d/topology/core_siblings_list", cpu);
}

int get_physical_package_id(int cpu)
{
- char path[80];
- FILE *filep;
- int pkg;
-
- sprintf(path, "/sys/devices/system/cpu/cpu%d/topology/physical_package_id", cpu);
- filep = fopen(path, "r");
- if (filep == NULL) {
- perror(path);
- exit(1);
- }
- if (fscanf(filep, "%d", &pkg) != 1) {
- perror(path);
- exit(1);
- }
- fclose(filep);
- return pkg;
+ return parse_int_file("/sys/devices/system/cpu/cpu%d/topology/physical_package_id", cpu);
}

int get_core_id(int cpu)
{
- char path[80];
- FILE *filep;
- int core;
-
- sprintf(path, "/sys/devices/system/cpu/cpu%d/topology/core_id", cpu);
- filep = fopen(path, "r");
- if (filep == NULL) {
- perror(path);
- exit(1);
- }
- if (fscanf(filep, "%d", &core) != 1) {
- perror(path);
- exit(1);
- }
- fclose(filep);
- return core;
+ return parse_int_file("/sys/devices/system/cpu/cpu%d/topology/core_id", cpu);
}

int get_num_ht_siblings(int cpu)
--
1.8.4.rc3

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