[dpdk-dev] [RFC 2/9] usertools/lib: add platform info library

[Anatoly Burakov <anatoly.burakov@intel.com>]

Add a library that will parse system information:

* NUMA nodes
* Cores and threads
* Mapping from NUMA node and core to thread id's
* Hyperthreading support status
* RAM size
* Default hugepage size as reported by kernel

This can be used by scripts.

Signed-off-by: Anatoly Burakov <anatoly.burakov@intel.com>
---
 usertools/DPDKConfigLib/PlatformInfo.py | 130 ++++++++++++++++++++++++
 usertools/DPDKConfigLib/Util.py         |  16 +++
 2 files changed, 146 insertions(+)
 create mode 100755 usertools/DPDKConfigLib/PlatformInfo.py
 create mode 100755 usertools/DPDKConfigLib/Util.py

diff --git a/usertools/DPDKConfigLib/PlatformInfo.py b/usertools/DPDKConfigLib/PlatformInfo.py
new file mode 100755
index 000000000..734d22026
--- /dev/null
+++ b/usertools/DPDKConfigLib/PlatformInfo.py
@@ -0,0 +1,130 @@
+#!/usr/bin/python
+# SPDX-License-Identifier: BSD-3-Clause
+# Copyright(c) 2018 Intel Corporation
+
+
+from .Util import *
+import re
+import glob
+
+__SYSFS_CPU_INFO_PATH = "/sys/devices/system/cpu"
+__SYSFS_IOMMU_CLASS_PATH = "/sys/class/iommu"
+__KERNEL_HPSZ_PATH = "/sys/kernel/mm/hugepages/hugepages-*"
+
+try:
+    xrange  # python 2
+except NameError:
+    xrange = range  # python 3
+
+
+__CPU_FLAGS_TO_HP_SIZE = {
+    # x86 supports 2M and 1G pages
+    "pse": 2048,
+    "pdpe1gb": 1048576
+}
+__IOMMU_CPU_FLAGS = ["vmx", "vms"]
+
+__HT_CPU_FLAGS = ["ht"]
+
+
+def _parse_cpuinfo(pinfo):
+    core_info_list = []
+    with open("/proc/cpuinfo") as f:
+        cur_core = {}
+        for line in f:
+            line = line.strip()
+            # if we've reached end of current core info, store it and clear it
+            if line == "":
+                core_info_list.append(cur_core)
+                cur_core = {}
+                continue
+            key, value = kv_split(line, ":")
+            cur_core[key] = value
+    # parse flags - they're the same for all CPU's so only parse the first one
+    flags = set(core_info_list[0]["flags"].split())
+    for flag in flags:
+        if flag in __CPU_FLAGS_TO_HP_SIZE:
+            pinfo.hugepage_sizes_supported.append(__CPU_FLAGS_TO_HP_SIZE[flag])
+        elif flag in __IOMMU_CPU_FLAGS:
+            pinfo.iommu_supported = True
+        elif flag in __HT_CPU_FLAGS:
+            pinfo.hyperthreading_supported = True
+
+    # parse cores and sockets
+    numa_nodes = set()
+    core_map = {}
+    for core_dict in core_info_list:
+        thread_id = int(core_dict["processor"])
+        core_id = int(core_dict["core id"])
+        numa_node = int(core_dict["physical id"])
+
+        core_map.setdefault((numa_node, core_id), []).append(thread_id)
+        numa_nodes.add(numa_node)
+
+    # now, populate PlatformInfo with our, well, info - convert to lists
+    pinfo.numa_nodes = list(numa_nodes)
+    pinfo.core_map = core_map
+
+
+def _parse_meminfo(pinfo):
+    meminfo_data = {}
+    with open("/proc/meminfo") as f:
+        for line in f:
+            key, value = kv_split(line, ":")
+            meminfo_data[key] = value
+
+    # regex used to capture kilobytes
+    r = re.compile("(\d+) kB")
+
+    # total ram size
+    m = r.match(meminfo_data["MemTotal"])
+    if not m:
+        raise RuntimeError("BUG: Bad regular expression")
+    pinfo.ram_size = int(m.group(1))
+
+    # hugepages may not be supported
+    if "Hugepagesize" in meminfo_data:
+        m = r.match(meminfo_data["Hugepagesize"])
+        if not m:
+            raise RuntimeError("BUG: Bad regular expression")
+        pinfo.default_hugepage_size = int(m.group(1))
+
+
+def _find_enabled_hugepage_sizes():
+    paths = glob.glob(__KERNEL_HPSZ_PATH)
+    r = re.compile("hugepages-(\d+)kB")
+    sizes = []
+    for p in paths:
+        p = os.path.basename(p)
+        m = r.search(p)
+        if not m:
+            raise RuntimeError("BUG: Bad regular expression")
+        sizes.append(int(m.group(1)))
+    return sizes
+
+
+def _iommu_is_enabled():
+    pass
+
+
+class PlatformInfo:
+    def __init__(self):
+        self.update()
+
+    def reset(self):
+        self.numa_nodes = []
+        self.hyperthreading_supported = False
+        self.core_map = {}  # numa_node, core_id: [thread_id]
+        self.iommu_supported = False
+        self.iommu_mode = ""
+        self.bootloader_iommu_mode = ""
+        self.hugepage_sizes_supported = []
+        self.hugepage_sizes_enabled = []
+        self.default_hugepage_size = 0
+        self.ram_size = 0
+
+    def update(self):
+        self.reset()
+        _parse_cpuinfo(self)
+        _parse_meminfo(self)
+        self.hugepage_sizes_enabled = _find_enabled_hugepage_sizes()
diff --git a/usertools/DPDKConfigLib/Util.py b/usertools/DPDKConfigLib/Util.py
new file mode 100755
index 000000000..42434e728
--- /dev/null
+++ b/usertools/DPDKConfigLib/Util.py
@@ -0,0 +1,16 @@
+#!/usr/bin/python
+# SPDX-License-Identifier: BSD-3-Clause
+# Copyright(c) 2018 Intel Corporation
+
+# split line into key-value pair, cleaning up the values in the process
+def kv_split(line, separator):
+    # just in case
+    line = line.strip()
+
+    tokens = line.split(separator, 1)
+    key, value = None, None
+    if len(tokens) > 0:
+        key = tokens[0].strip()
+    if len(tokens) > 1:
+        value = tokens[1].strip()
+    return key, value
-- 
2.17.1