Imported Upstream version 16.04

[deb_dpdk.git] / lib / librte_eal / linuxapp / eal / eal_lcore.c

diff --git a/lib/librte_eal/linuxapp/eal/eal_lcore.c b/lib/librte_eal/linuxapp/eal/eal_lcore.c
new file mode 100644 (file)
index 0000000..de5b426
--- /dev/null
+++ b/lib/librte_eal/linuxapp/eal/eal_lcore.c
@@ -0,0 +1,110 @@
+/*-
+ *   BSD LICENSE
+ *
+ *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
+ *   All rights reserved.
+ *
+ *   Redistribution and use in source and binary forms, with or without
+ *   modification, are permitted provided that the following conditions
+ *   are met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in
+ *       the documentation and/or other materials provided with the
+ *       distribution.
+ *     * Neither the name of Intel Corporation nor the names of its
+ *       contributors may be used to endorse or promote products derived
+ *       from this software without specific prior written permission.
+ *
+ *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <unistd.h>
+#include <limits.h>
+#include <string.h>
+#include <dirent.h>
+
+#include <rte_log.h>
+#include <rte_eal.h>
+#include <rte_lcore.h>
+#include <rte_common.h>
+#include <rte_string_fns.h>
+#include <rte_debug.h>
+
+#include "eal_private.h"
+#include "eal_filesystem.h"
+#include "eal_thread.h"
+
+#define SYS_CPU_DIR "/sys/devices/system/cpu/cpu%u"
+#define CORE_ID_FILE "topology/core_id"
+#define NUMA_NODE_PATH "/sys/devices/system/node"
+
+/* Check if a cpu is present by the presence of the cpu information for it */
+int
+eal_cpu_detected(unsigned lcore_id)
+{
+       char path[PATH_MAX];
+       int len = snprintf(path, sizeof(path), SYS_CPU_DIR
+               "/"CORE_ID_FILE, lcore_id);
+       if (len <= 0 || (unsigned)len >= sizeof(path))
+               return 0;
+       if (access(path, F_OK) != 0)
+               return 0;
+
+       return 1;
+}
+
+/*
+ * 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)
+{
+       unsigned socket;
+
+       for (socket = 0; socket < RTE_MAX_NUMA_NODES; socket++) {
+               char path[PATH_MAX];
+
+               snprintf(path, sizeof(path), "%s/node%u/cpu%u", NUMA_NODE_PATH,
+                               socket, lcore_id);
+               if (access(path, F_OK) == 0)
+                       return socket;
+       }
+       return 0;
+}
+
+/* Get the cpu core id value from the /sys/.../cpuX core_id value */
+unsigned
+eal_cpu_core_id(unsigned lcore_id)
+{
+       char path[PATH_MAX];
+       unsigned long id;
+
+       int len = snprintf(path, sizeof(path), SYS_CPU_DIR "/%s", lcore_id, CORE_ID_FILE);
+       if (len <= 0 || (unsigned)len >= sizeof(path))
+               goto err;
+       if (eal_parse_sysfs_value(path, &id) != 0)
+               goto err;
+       return (unsigned)id;
+
+err:
+       RTE_LOG(ERR, EAL, "Error reading core id value from %s "
+                       "for lcore %u - assuming core 0\n", SYS_CPU_DIR, lcore_id);
+       return 0;
+}