vppinfra: add clib_mem_vm_ext_alloc function

Change-Id: Iff33694fc42cc3bcc73cf1372339053a6365039c
Signed-off-by: Damjan Marion <damarion@cisco.com>

1 files changed, 250 insertions, 0 deletions

diff --git a/src/vppinfra/linux/sysfs.c b/src/vppinfra/linux/sysfs.c
new file mode 100644
index 00000000000..5f611e6a341
--- /dev/null
+++ b/src/vppinfra/linux/sysfs.c
@@ -0,0 +1,250 @@
+/*
+ * Copyright (c) 2017 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <vppinfra/clib.h>
+#include <vppinfra/clib_error.h>
+#include <vppinfra/format.h>
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <dirent.h>
+
+clib_error_t *
+clib_sysfs_write (char *file_name, char *fmt, ...)
+{
+  u8 *s;
+  int fd;
+  clib_error_t *error = 0;
+
+  fd = open (file_name, O_WRONLY);
+  if (fd < 0)
+    return clib_error_return_unix (0, "open `%s'", file_name);
+
+  va_list va;
+  va_start (va, fmt);
+  s = va_format (0, fmt, &va);
+  va_end (va);
+
+  if (write (fd, s, vec_len (s)) < 0)
+    error = clib_error_return_unix (0, "write `%s'", file_name);
+
+  vec_free (s);
+  close (fd);
+  return error;
+}
+
+clib_error_t *
+clib_sysfs_read (char *file_name, char *fmt, ...)
+{
+  unformat_input_t input;
+  u8 *s = 0;
+  int fd;
+  ssize_t sz;
+  uword result;
+
+  fd = open (file_name, O_RDONLY);
+  if (fd < 0)
+    return clib_error_return_unix (0, "open `%s'", file_name);
+
+  vec_validate (s, 4095);
+
+  sz = read (fd, s, vec_len (s));
+  if (sz < 0)
+    {
+      close (fd);
+      vec_free (s);
+      return clib_error_return_unix (0, "read `%s'", file_name);
+    }
+
+  _vec_len (s) = sz;
+  unformat_init_vector (&input, s);
+
+  va_list va;
+  va_start (va, fmt);
+  result = va_unformat (&input, fmt, &va);
+  va_end (va);
+
+  vec_free (s);
+  close (fd);
+
+  if (result == 0)
+    return clib_error_return (0, "unformat error");
+
+  return 0;
+}
+
+u8 *
+clib_sysfs_link_to_name (char *link)
+{
+  char *p, buffer[64];
+  unformat_input_t in;
+  u8 *s = 0;
+  int r;
+
+  r = readlink (link, buffer, sizeof (buffer) - 1);
+
+  if (r < 0)
+    return 0;
+
+  buffer[r] = 0;
+  p = strrchr (buffer, '/');
+
+  if (!p)
+    return 0;
+
+  unformat_init_string (&in, p + 1, strlen (p + 1));
+  if (unformat (&in, "%s", &s) != 1)
+    clib_unix_warning ("no string?");
+  unformat_free (&in);
+
+  return s;
+}
+
+clib_error_t *
+clib_sysfs_set_nr_hugepages (int numa_node, int page_size, int nr)
+{
+  clib_error_t *error = 0;
+  struct stat sb;
+  u8 *p = 0;
+
+  p = format (p, "/sys/devices/system/node/node%u%c", numa_node, 0);
+
+  if (stat ((char *) p, &sb) == 0)
+    {
+      if (S_ISDIR (sb.st_mode) == 0)
+	{
+	  error = clib_error_return (0, "'%s' is not directory", p);
+	  goto done;
+	}
+    }
+  else if (numa_node == 0)
+    {
+      vec_reset_length (p);
+      p = format (p, "/sys/kernel/mm%c", 0);
+      if (stat ((char *) p, &sb) < 0 || S_ISDIR (sb.st_mode) == 0)
+	{
+	  error = clib_error_return (0, "'%s' does not exist or it is not "
+				     "directory", p);
+	  goto done;
+	}
+    }
+  else
+    {
+      error = clib_error_return (0, "'%s' does not exist", p);
+      goto done;
+    }
+
+  _vec_len (p) -= 1;
+  p = format (p, "/hugepages/hugepages-%ukB/nr_hugepages%c", page_size, 0);
+  clib_sysfs_write ((char *) p, "%d", nr);
+
+done:
+  vec_free (p);
+  return error;
+}
+
+
+static clib_error_t *
+clib_sysfs_get_xxx_hugepages (char *type, int numa_node,
+			      int page_size, int *val)
+{
+  clib_error_t *error = 0;
+  struct stat sb;
+  u8 *p = 0;
+
+  p = format (p, "/sys/devices/system/node/node%u%c", numa_node, 0);
+
+  if (stat ((char *) p, &sb) == 0)
+    {
+      if (S_ISDIR (sb.st_mode) == 0)
+	{
+	  error = clib_error_return (0, "'%s' is not directory", p);
+	  goto done;
+	}
+    }
+  else if (numa_node == 0)
+    {
+      vec_reset_length (p);
+      p = format (p, "/sys/kernel/mm%c", 0);
+      if (stat ((char *) p, &sb) < 0 || S_ISDIR (sb.st_mode) == 0)
+	{
+	  error = clib_error_return (0, "'%s' does not exist or it is not "
+				     "directory", p);
+	  goto done;
+	}
+    }
+  else
+    {
+      error = clib_error_return (0, "'%s' does not exist", p);
+      goto done;
+    }
+
+  _vec_len (p) -= 1;
+  p = format (p, "/hugepages/hugepages-%ukB/%s_hugepages%c", page_size,
+	      type, 0);
+  error = clib_sysfs_read ((char *) p, "%d", val);
+
+done:
+  vec_free (p);
+  return error;
+}
+
+clib_error_t *
+clib_sysfs_get_free_hugepages (int numa_node, int page_size, int *v)
+{
+  return clib_sysfs_get_xxx_hugepages ("free", numa_node, page_size, v);
+}
+
+clib_error_t *
+clib_sysfs_get_nr_hugepages (int numa_node, int page_size, int *v)
+{
+  return clib_sysfs_get_xxx_hugepages ("nr", numa_node, page_size, v);
+}
+
+clib_error_t *
+clib_sysfs_get_surplus_hugepages (int numa_node, int page_size, int *v)
+{
+  return clib_sysfs_get_xxx_hugepages ("surplus", numa_node, page_size, v);
+}
+
+clib_error_t *
+clib_sysfs_prealloc_hugepages (int numa_node, int page_size, int nr)
+{
+  clib_error_t *error = 0;
+  int n, needed;
+  error = clib_sysfs_get_free_hugepages (numa_node, page_size, &n);
+  if (error)
+    return error;
+  needed = nr - n;
+  if (needed <= 0)
+    return 0;
+
+  error = clib_sysfs_get_nr_hugepages (numa_node, page_size, &n);
+  if (error)
+    return error;
+  clib_warning ("pre-allocating %u additional %uK hugepages on numa node %u",
+		needed, page_size, numa_node);
+  return clib_sysfs_set_nr_hugepages (numa_node, page_size, n + needed);
+}
+
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */