Adding upstream version 18.2.2.upstream/18.2.2

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 260 insertions, 0 deletions

diff --git a/src/common/numa.cc b/src/common/numa.cc
new file mode 100644
index 000000000..f62f0d010
--- /dev/null
+++ b/src/common/numa.cc
@@ -0,0 +1,260 @@
+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+// vim: ts=8 sw=2 smarttab
+
+#include "numa.h"
+
+#include <cstring>
+#include <errno.h>
+#include <iostream>
+
+#include "include/stringify.h"
+#include "common/safe_io.h"
+
+using namespace std::literals;
+
+using std::set;
+
+
+// list
+#if defined(__linux__)
+int parse_cpu_set_list(const char *s,
+		       size_t *cpu_set_size,
+		       cpu_set_t *cpu_set)
+{
+  CPU_ZERO(cpu_set);
+  while (*s) {
+    char *end;
+    int a = strtol(s, &end, 10);
+    if (end == s) {
+      return -EINVAL;
+    }
+    if (*end == '-') {
+      s = end + 1;
+      int b = strtol(s, &end, 10);
+      if (end == s) {
+	return -EINVAL;
+      }
+      for (; a <= b; ++a) {
+	CPU_SET(a, cpu_set);
+      }
+      *cpu_set_size = a;
+    } else {
+      CPU_SET(a, cpu_set);
+      *cpu_set_size = a + 1;
+    }
+    if (*end == 0) {
+      break;
+    }
+    if (*end != ',') {
+      return -EINVAL;
+    }
+    s = end + 1;
+  }
+  return 0;
+}
+
+std::string cpu_set_to_str_list(size_t cpu_set_size,
+				const cpu_set_t *cpu_set)
+{
+  std::string r;
+  unsigned a = 0;
+  while (true) {
+    while (a < cpu_set_size && !CPU_ISSET(a, cpu_set)) {
+      ++a;
+    }
+    if (a >= cpu_set_size) {
+      break;
+    }
+    unsigned b = a + 1;
+    while (b < cpu_set_size && CPU_ISSET(b, cpu_set)) {
+      ++b;
+    }
+    if (r.size()) {
+      r += ",";
+    }
+    if (b > a + 1) {
+      r += stringify(a) + "-" + stringify(b - 1);
+    } else {
+      r += stringify(a);
+    }
+    a = b;
+  }
+  return r;
+}
+
+std::set<int> cpu_set_to_set(size_t cpu_set_size,
+			     const cpu_set_t *cpu_set)
+{
+  set<int> r;
+  unsigned a = 0;
+  while (true) {
+    while (a < cpu_set_size && !CPU_ISSET(a, cpu_set)) {
+      ++a;
+    }
+    if (a >= cpu_set_size) {
+      break;
+    }
+    unsigned b = a + 1;
+    while (b < cpu_set_size && CPU_ISSET(b, cpu_set)) {
+      ++b;
+    }
+    while (a < b) {
+      r.insert(a);
+      ++a;
+    }
+  }
+  return r;
+}
+
+
+int get_numa_node_cpu_set(
+  int node,
+  size_t *cpu_set_size,
+  cpu_set_t *cpu_set)
+{
+  std::string fn = "/sys/devices/system/node/node";
+  fn += stringify(node);
+  fn += "/cpulist";
+  int fd = ::open(fn.c_str(), O_RDONLY);
+  if (fd < 0) {
+    return -errno;
+  }
+  char buf[1024];
+  int r = safe_read(fd, &buf, sizeof(buf));
+  if (r < 0) {
+    goto out;
+  }
+  buf[r] = 0;
+  while (r > 0 && ::isspace(buf[--r])) {
+    buf[r] = 0;
+  }
+  r = parse_cpu_set_list(buf, cpu_set_size, cpu_set);
+  if (r < 0) {
+    goto out;
+  }
+  r = 0;
+ out:
+  ::close(fd);
+  return r;
+}
+
+static int easy_readdir(const std::string& dir, std::set<std::string> *out)
+{
+  DIR *h = ::opendir(dir.c_str());
+  if (!h) {
+    return -errno;
+  }
+  struct dirent *de = nullptr;
+  while ((de = ::readdir(h))) {
+    if (strcmp(de->d_name, ".") == 0 ||
+	strcmp(de->d_name, "..") == 0) {
+      continue;
+    }
+    out->insert(de->d_name);
+  }
+  closedir(h);
+  return 0;
+}
+
+#ifdef HAVE_DPDK
+static std::string get_task_comm(pid_t tid)
+{
+  static const char* comm_fmt = "/proc/self/task/%d/comm";
+  char comm_name[strlen(comm_fmt) + 8];
+  snprintf(comm_name, sizeof(comm_name), comm_fmt, tid);
+  int fd = open(comm_name, O_CLOEXEC | O_RDONLY);
+  if (fd == -1) {
+    return "";
+  }
+  // see linux/sched.h
+  static constexpr int TASK_COMM_LEN = 16;
+  char name[TASK_COMM_LEN];
+  ssize_t n = safe_read(fd, name, sizeof(name));
+  close(fd);
+  if (n < 0) {
+    return "";
+  }
+  assert(static_cast<size_t>(n) <= sizeof(name));
+  if (name[n - 1] == '\n') {
+    name[n - 1] = '\0';
+  } else {
+    name[n] = '\0';
+  }
+  return name;
+}
+#endif
+
+int set_cpu_affinity_all_threads(size_t cpu_set_size, cpu_set_t *cpu_set)
+{
+  // first set my affinity
+  int r = sched_setaffinity(getpid(), cpu_set_size, cpu_set);
+  if (r < 0) {
+    return -errno;
+  }
+
+  // make 2 passes here so that we (hopefully) catch racing threads creating
+  // threads.
+  for (unsigned pass = 0; pass < 2; ++pass) {
+    // enumerate all child threads from /proc
+    std::set<std::string> ls;
+    std::string path = "/proc/"s + stringify(getpid()) + "/task";
+    r = easy_readdir(path, &ls);
+    if (r < 0) {
+      return r;
+    }
+    for (auto& i : ls) {
+      pid_t tid = atoll(i.c_str());
+      if (!tid) {
+	continue;  // wtf
+      }
+      #ifdef HAVE_DPDK
+      std::string thread_name = get_task_comm(tid);
+      static const char *dpdk_worker_name = "lcore-worker";
+      if (!thread_name.compare(0, strlen(dpdk_worker_name), dpdk_worker_name)) {
+	// ignore dpdk reactor thread, as it takes case of numa by itself
+        continue;
+      }
+      #endif
+      r = sched_setaffinity(tid, cpu_set_size, cpu_set);
+      if (r < 0) {
+	return -errno;
+      }
+    }
+  }
+  return 0;
+}
+
+#else
+int parse_cpu_set_list(const char *s,
+		       size_t *cpu_set_size,
+		       cpu_set_t *cpu_set)
+{
+  return -ENOTSUP;
+}
+
+std::string cpu_set_to_str_list(size_t cpu_set_size,
+				const cpu_set_t *cpu_set)
+{
+  return {};
+}
+
+std::set<int> cpu_set_to_set(size_t cpu_set_size,
+			     const cpu_set_t *cpu_set)
+{
+  return {};
+}
+
+int get_numa_node_cpu_set(int node,
+                          size_t *cpu_set_size,
+                          cpu_set_t *cpu_set)
+{
+  return -ENOTSUP;
+}
+
+int set_cpu_affinity_all_threads(size_t cpu_set_size,
+				 cpu_set_t *cpu_set)
+{
+  return -ENOTSUP;
+}
+
+#endif