#define SYS_CPU_DIR "/sys/devices/system/cpu/cpu%u"
#define CORE_ID_FILE "topology/core_id"
-#define PHYS_PKG_FILE "topology/physical_package_id"
+#define NUMA_NODE_PATH "/sys/devices/system/node"
/* Check if a cpu is present by the presence of the cpu information for it */
-static int
-cpu_detected(unsigned lcore_id)
+int
+eal_cpu_detected(unsigned lcore_id)
{
char path[PATH_MAX];
int len = snprintf(path, sizeof(path), SYS_CPU_DIR
return 1;
}
-/* Get CPU socket id (NUMA node) by reading directory
- * /sys/devices/system/cpu/cpuX looking for symlink "nodeY"
- * which gives the NUMA topology information.
- * Note: physical package id != NUMA node, but we use it as a
- * fallback for kernels which don't create a nodeY link
+/*
+ * Get CPU socket id (NUMA node) for a logical core.
+ *
+ * This searches each nodeX directories in /sys for the symlink for the given
+ * lcore_id and returns the numa node where the lcore is found. If lcore is not
+ * found on any numa node, returns zero.
*/
unsigned
eal_cpu_socket_id(unsigned lcore_id)
{
- const char node_prefix[] = "node";
- const size_t prefix_len = sizeof(node_prefix) - 1;
- char path[PATH_MAX];
- DIR *d = NULL;
- unsigned long id = 0;
- struct dirent *e;
- char *endptr = NULL;
-
- int len = snprintf(path, sizeof(path),
- SYS_CPU_DIR, lcore_id);
- if (len <= 0 || (unsigned)len >= sizeof(path))
- goto err;
+ unsigned socket;
- d = opendir(path);
- if (!d)
- goto err;
-
- while ((e = readdir(d)) != NULL) {
- if (strncmp(e->d_name, node_prefix, prefix_len) == 0) {
- id = strtoul(e->d_name+prefix_len, &endptr, 0);
- break;
- }
- }
- if (endptr == NULL || *endptr!='\0' || endptr == e->d_name+prefix_len) {
- RTE_LOG(WARNING, EAL, "Cannot read numa node link "
- "for lcore %u - using physical package id instead\n",
- lcore_id);
+ for (socket = 0; socket < RTE_MAX_NUMA_NODES; socket++) {
+ char path[PATH_MAX];
- len = snprintf(path, sizeof(path), SYS_CPU_DIR "/%s",
- lcore_id, PHYS_PKG_FILE);
- if (len <= 0 || (unsigned)len >= sizeof(path))
- goto err;
- if (eal_parse_sysfs_value(path, &id) != 0)
- goto err;
+ snprintf(path, sizeof(path), "%s/node%u/cpu%u", NUMA_NODE_PATH,
+ socket, lcore_id);
+ if (access(path, F_OK) == 0)
+ return socket;
}
- closedir(d);
- return (unsigned)id;
-
-err:
- if (d)
- closedir(d);
- RTE_LOG(ERR, EAL, "Error getting NUMA socket information from %s "
- "for lcore %u - assuming NUMA socket 0\n", SYS_CPU_DIR, lcore_id);
return 0;
}
/* Get the cpu core id value from the /sys/.../cpuX core_id value */
-static unsigned
-cpu_core_id(unsigned lcore_id)
+unsigned
+eal_cpu_core_id(unsigned lcore_id)
{
char path[PATH_MAX];
unsigned long id;
"for lcore %u - assuming core 0\n", SYS_CPU_DIR, lcore_id);
return 0;
}
-
-/*
- * Parse /sys/devices/system/cpu to get the number of physical and logical
- * processors on the machine. The function will fill the cpu_info
- * structure.
- */
-int
-rte_eal_cpu_init(void)
-{
- /* pointer to global configuration */
- struct rte_config *config = rte_eal_get_configuration();
- unsigned lcore_id;
- unsigned count = 0;
-
- /*
- * Parse the maximum set of logical cores, detect the subset of running
- * ones and enable them by default.
- */
- for (lcore_id = 0; lcore_id < RTE_MAX_LCORE; lcore_id++) {
- /* init cpuset for per lcore config */
- CPU_ZERO(&lcore_config[lcore_id].cpuset);
-
- /* in 1:1 mapping, record related cpu detected state */
- lcore_config[lcore_id].detected = cpu_detected(lcore_id);
- if (lcore_config[lcore_id].detected == 0) {
- config->lcore_role[lcore_id] = ROLE_OFF;
- continue;
- }
-
- /* By default, lcore 1:1 map to cpu id */
- CPU_SET(lcore_id, &lcore_config[lcore_id].cpuset);
-
- /* By default, each detected core is enabled */
- config->lcore_role[lcore_id] = ROLE_RTE;
- lcore_config[lcore_id].core_id = cpu_core_id(lcore_id);
- lcore_config[lcore_id].socket_id = eal_cpu_socket_id(lcore_id);
- if (lcore_config[lcore_id].socket_id >= RTE_MAX_NUMA_NODES)
-#ifdef RTE_EAL_ALLOW_INV_SOCKET_ID
- lcore_config[lcore_id].socket_id = 0;
-#else
- rte_panic("Socket ID (%u) is greater than "
- "RTE_MAX_NUMA_NODES (%d)\n",
- lcore_config[lcore_id].socket_id, RTE_MAX_NUMA_NODES);
-#endif
- RTE_LOG(DEBUG, EAL, "Detected lcore %u as core %u on socket %u\n",
- lcore_id,
- lcore_config[lcore_id].core_id,
- lcore_config[lcore_id].socket_id);
- count ++;
- }
- /* Set the count of enabled logical cores of the EAL configuration */
- config->lcore_count = count;
- RTE_LOG(DEBUG, EAL, "Support maximum %u logical core(s) by configuration.\n",
- RTE_MAX_LCORE);
- RTE_LOG(DEBUG, EAL, "Detected %u lcore(s)\n", config->lcore_count);
-
- return 0;
-}