mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-21 08:19:28 +00:00
perf tools: Allow ability to map cpus to nodes easily
This patch figures out the max number of cpus and nodes that are on the system and creates a map of cpu to node. This allows us to provide a cpu and quickly get the node associated with it. It was mostly copied from builtin-kmem.c and tweaked slightly to use less memory (use possible cpus instead of max). It also calculates the max number of nodes. Signed-off-by: Don Zickus <dzickus@redhat.com> Reviewed-by: Namhyung Kim <namhyung@kernel.org> Link: http://lkml.kernel.org/r/1396896924-129847-2-git-send-email-dzickus@redhat.com [ Removing out label code in init_cpunode_map ] [ Adding check for snprintf error ] [ Removing unneeded returns ] Signed-off-by: Jiri Olsa <jolsa@redhat.com>
This commit is contained in:
parent
7c2f8164e5
commit
7780c25bae
2 changed files with 195 additions and 0 deletions
|
@ -317,3 +317,163 @@ int cpu_map__build_core_map(struct cpu_map *cpus, struct cpu_map **corep)
|
|||
{
|
||||
return cpu_map__build_map(cpus, corep, cpu_map__get_core);
|
||||
}
|
||||
|
||||
/* setup simple routines to easily access node numbers given a cpu number */
|
||||
static int get_max_num(char *path, int *max)
|
||||
{
|
||||
size_t num;
|
||||
char *buf;
|
||||
int err = 0;
|
||||
|
||||
if (filename__read_str(path, &buf, &num))
|
||||
return -1;
|
||||
|
||||
buf[num] = '\0';
|
||||
|
||||
/* start on the right, to find highest node num */
|
||||
while (--num) {
|
||||
if ((buf[num] == ',') || (buf[num] == '-')) {
|
||||
num++;
|
||||
break;
|
||||
}
|
||||
}
|
||||
if (sscanf(&buf[num], "%d", max) < 1) {
|
||||
err = -1;
|
||||
goto out;
|
||||
}
|
||||
|
||||
/* convert from 0-based to 1-based */
|
||||
(*max)++;
|
||||
|
||||
out:
|
||||
free(buf);
|
||||
return err;
|
||||
}
|
||||
|
||||
/* Determine highest possible cpu in the system for sparse allocation */
|
||||
static void set_max_cpu_num(void)
|
||||
{
|
||||
const char *mnt;
|
||||
char path[PATH_MAX];
|
||||
int ret = -1;
|
||||
|
||||
/* set up default */
|
||||
max_cpu_num = 4096;
|
||||
|
||||
mnt = sysfs__mountpoint();
|
||||
if (!mnt)
|
||||
goto out;
|
||||
|
||||
/* get the highest possible cpu number for a sparse allocation */
|
||||
ret = snprintf(path, PATH_MAX, "%s/devices/system/cpu/kernel_max", mnt);
|
||||
if (ret == PATH_MAX) {
|
||||
pr_err("sysfs path crossed PATH_MAX(%d) size\n", PATH_MAX);
|
||||
goto out;
|
||||
}
|
||||
|
||||
ret = get_max_num(path, &max_cpu_num);
|
||||
|
||||
out:
|
||||
if (ret)
|
||||
pr_err("Failed to read max cpus, using default of %d\n", max_cpu_num);
|
||||
}
|
||||
|
||||
/* Determine highest possible node in the system for sparse allocation */
|
||||
static void set_max_node_num(void)
|
||||
{
|
||||
const char *mnt;
|
||||
char path[PATH_MAX];
|
||||
int ret = -1;
|
||||
|
||||
/* set up default */
|
||||
max_node_num = 8;
|
||||
|
||||
mnt = sysfs__mountpoint();
|
||||
if (!mnt)
|
||||
goto out;
|
||||
|
||||
/* get the highest possible cpu number for a sparse allocation */
|
||||
ret = snprintf(path, PATH_MAX, "%s/devices/system/node/possible", mnt);
|
||||
if (ret == PATH_MAX) {
|
||||
pr_err("sysfs path crossed PATH_MAX(%d) size\n", PATH_MAX);
|
||||
goto out;
|
||||
}
|
||||
|
||||
ret = get_max_num(path, &max_node_num);
|
||||
|
||||
out:
|
||||
if (ret)
|
||||
pr_err("Failed to read max nodes, using default of %d\n", max_node_num);
|
||||
}
|
||||
|
||||
static int init_cpunode_map(void)
|
||||
{
|
||||
int i;
|
||||
|
||||
set_max_cpu_num();
|
||||
set_max_node_num();
|
||||
|
||||
cpunode_map = calloc(max_cpu_num, sizeof(int));
|
||||
if (!cpunode_map) {
|
||||
pr_err("%s: calloc failed\n", __func__);
|
||||
return -1;
|
||||
}
|
||||
|
||||
for (i = 0; i < max_cpu_num; i++)
|
||||
cpunode_map[i] = -1;
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
int cpu__setup_cpunode_map(void)
|
||||
{
|
||||
struct dirent *dent1, *dent2;
|
||||
DIR *dir1, *dir2;
|
||||
unsigned int cpu, mem;
|
||||
char buf[PATH_MAX];
|
||||
char path[PATH_MAX];
|
||||
const char *mnt;
|
||||
int n;
|
||||
|
||||
/* initialize globals */
|
||||
if (init_cpunode_map())
|
||||
return -1;
|
||||
|
||||
mnt = sysfs__mountpoint();
|
||||
if (!mnt)
|
||||
return 0;
|
||||
|
||||
n = snprintf(path, PATH_MAX, "%s/devices/system/node", mnt);
|
||||
if (n == PATH_MAX) {
|
||||
pr_err("sysfs path crossed PATH_MAX(%d) size\n", PATH_MAX);
|
||||
return -1;
|
||||
}
|
||||
|
||||
dir1 = opendir(path);
|
||||
if (!dir1)
|
||||
return 0;
|
||||
|
||||
/* walk tree and setup map */
|
||||
while ((dent1 = readdir(dir1)) != NULL) {
|
||||
if (dent1->d_type != DT_DIR || sscanf(dent1->d_name, "node%u", &mem) < 1)
|
||||
continue;
|
||||
|
||||
n = snprintf(buf, PATH_MAX, "%s/%s", path, dent1->d_name);
|
||||
if (n == PATH_MAX) {
|
||||
pr_err("sysfs path crossed PATH_MAX(%d) size\n", PATH_MAX);
|
||||
continue;
|
||||
}
|
||||
|
||||
dir2 = opendir(buf);
|
||||
if (!dir2)
|
||||
continue;
|
||||
while ((dent2 = readdir(dir2)) != NULL) {
|
||||
if (dent2->d_type != DT_LNK || sscanf(dent2->d_name, "cpu%u", &cpu) < 1)
|
||||
continue;
|
||||
cpunode_map[cpu] = mem;
|
||||
}
|
||||
closedir(dir2);
|
||||
}
|
||||
closedir(dir1);
|
||||
return 0;
|
||||
}
|
||||
|
|
|
@ -4,6 +4,9 @@
|
|||
#include <stdio.h>
|
||||
#include <stdbool.h>
|
||||
|
||||
#include "perf.h"
|
||||
#include "util/debug.h"
|
||||
|
||||
struct cpu_map {
|
||||
int nr;
|
||||
int map[];
|
||||
|
@ -46,4 +49,36 @@ static inline bool cpu_map__empty(const struct cpu_map *map)
|
|||
return map ? map->map[0] == -1 : true;
|
||||
}
|
||||
|
||||
int max_cpu_num;
|
||||
int max_node_num;
|
||||
int *cpunode_map;
|
||||
|
||||
int cpu__setup_cpunode_map(void);
|
||||
|
||||
static inline int cpu__max_node(void)
|
||||
{
|
||||
if (unlikely(!max_node_num))
|
||||
pr_debug("cpu_map not initialized\n");
|
||||
|
||||
return max_node_num;
|
||||
}
|
||||
|
||||
static inline int cpu__max_cpu(void)
|
||||
{
|
||||
if (unlikely(!max_cpu_num))
|
||||
pr_debug("cpu_map not initialized\n");
|
||||
|
||||
return max_cpu_num;
|
||||
}
|
||||
|
||||
static inline int cpu__get_node(int cpu)
|
||||
{
|
||||
if (unlikely(cpunode_map == NULL)) {
|
||||
pr_debug("cpu_map not initialized\n");
|
||||
return -1;
|
||||
}
|
||||
|
||||
return cpunode_map[cpu];
|
||||
}
|
||||
|
||||
#endif /* __PERF_CPUMAP_H */
|
||||
|
|
Loading…
Reference in a new issue