[PATCH 4/4] perf tools: Use sysfs__mountpoint() when reading cpu topology

From: Jiri Olsa
Date: Tue Feb 19 2019 - 04:58:39 EST


Using sysfs__mountpoint() when reading sysfs files
for cpu/numa topology.

Also using scnprintf instead of sprintf as suggested
by Namhyung.

Link: http://lkml.kernel.org/n/tip-pny10k3m9459q6f2j7ot7uzs@xxxxxxxxxxxxxx
Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
---
tools/perf/util/cputopo.c | 29 ++++++++++++++++++++++-------
1 file changed, 22 insertions(+), 7 deletions(-)

diff --git a/tools/perf/util/cputopo.c b/tools/perf/util/cputopo.c
index 83ffca2ea9ee..ece0710249d4 100644
--- a/tools/perf/util/cputopo.c
+++ b/tools/perf/util/cputopo.c
@@ -1,6 +1,7 @@
// SPDX-License-Identifier: GPL-2.0
#include <sys/param.h>
#include <inttypes.h>
+#include <api/fs/fs.h>

#include "cputopo.h"
#include "cpumap.h"
@@ -9,9 +10,15 @@


#define CORE_SIB_FMT \
- "/sys/devices/system/cpu/cpu%d/topology/core_siblings_list"
+ "%s/devices/system/cpu/cpu%d/topology/core_siblings_list"
#define THRD_SIB_FMT \
- "/sys/devices/system/cpu/cpu%d/topology/thread_siblings_list"
+ "%s/devices/system/cpu/cpu%d/topology/thread_siblings_list"
+#define NODE_ONLINE_FMT \
+ "%s/devices/system/node/online"
+#define NODE_MEMINFO_FMT \
+ "%s/devices/system/node/node%d/meminfo"
+#define NODE_CPULIST_FMT \
+ "%s/devices/system/node/node%d/cpulist"

static int build_cpu_topology(struct cpu_topology *tp, int cpu)
{
@@ -23,7 +30,8 @@ static int build_cpu_topology(struct cpu_topology *tp, int cpu)
u32 i = 0;
int ret = -1;

- sprintf(filename, CORE_SIB_FMT, cpu);
+ scnprintf(filename, MAXPATHLEN, CORE_SIB_FMT,
+ sysfs__mountpoint(), cpu);
fp = fopen(filename, "r");
if (!fp)
goto try_threads;
@@ -50,7 +58,8 @@ static int build_cpu_topology(struct cpu_topology *tp, int cpu)
ret = 0;

try_threads:
- sprintf(filename, THRD_SIB_FMT, cpu);
+ scnprintf(filename, MAXPATHLEN, THRD_SIB_FMT,
+ sysfs__mountpoint(), cpu);
fp = fopen(filename, "r");
if (!fp)
goto done;
@@ -157,7 +166,8 @@ static int load_numa_node(struct numa_topology_node *node, int nr)

node->node = (u32) nr;

- sprintf(str, "/sys/devices/system/node/node%d/meminfo", nr);
+ scnprintf(str, MAXPATHLEN, NODE_MEMINFO_FMT,
+ sysfs__mountpoint(), nr);
fp = fopen(str, "r");
if (!fp)
return -1;
@@ -179,7 +189,8 @@ static int load_numa_node(struct numa_topology_node *node, int nr)
fclose(fp);
fp = NULL;

- sprintf(str, "/sys/devices/system/node/node%d/cpulist", nr);
+ scnprintf(str, MAXPATHLEN, NODE_CPULIST_FMT,
+ sysfs__mountpoint(), nr);

fp = fopen(str, "r");
if (!fp)
@@ -207,13 +218,17 @@ struct numa_topology *numa_topology__new(void)
{
struct cpu_map *node_map = NULL;
struct numa_topology *tp = NULL;
+ char path[MAXPATHLEN];
char *buf = NULL;
size_t len = 0;
u32 nr, i;
FILE *fp;
char *c;

- fp = fopen("/sys/devices/system/node/online", "r");
+ scnprintf(path, MAXPATHLEN, NODE_ONLINE_FMT,
+ sysfs__mountpoint());
+
+ fp = fopen(path, "r");
if (!fp)
return NULL;

--
2.17.2