X86_64 perf counter plugin

Change-Id: Ie5a00c15ee9536cc61afab57f6cadc1aa1972f3c
Signed-off-by: Dave Barach <dave@barachs.net>

1 files changed, 235 insertions, 0 deletions

diff --git a/src/plugins/perfmon/parse_util.c b/src/plugins/perfmon/parse_util.c
new file mode 100644
index 00000000000..436acaa6de0
--- /dev/null
+++ b/src/plugins/perfmon/parse_util.c
@@ -0,0 +1,235 @@
+/*
+ * parse_util.c - halfhearted json parser
+ *
+ * Copyright (c) 2018 Cisco Systems 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 <perfmon/perfmon.h>
+#include <vppinfra/unix.h>
+
+typedef enum
+{
+  STATE_START,
+  STATE_READ_NAME,
+  STATE_READ_VALUE,
+} parse_state_t;
+
+static u8 *
+downcase (u8 * s)
+{
+  u8 *rv = 0;
+  u8 c;
+  int i;
+
+  for (i = 0; i < vec_len (s); i++)
+    {
+      c = s[i];
+      if (c >= 'A' && c <= 'Z')
+	c = c + ('a' - 'A');
+      vec_add1 (rv, c);
+    }
+  return (rv);
+}
+
+uword *
+perfmon_parse_table (perfmon_main_t * pm, char *path, char *table_name)
+{
+  u8 *cp;
+  u8 *event_name;
+  int state = STATE_START;
+  uword *ht;
+  name_value_pair_t *nvp = 0;
+  name_value_pair_t **nvps = 0;
+  u8 *v;
+  int i;
+  u8 *json_filename;
+  clib_error_t *error;
+
+  /* Create the name/value hash table in any case... */
+  ht = hash_create_string (0, sizeof (uword));
+
+  json_filename = format (0, "%s/%s%c", path, table_name, 0);
+
+  vlib_log_debug (pm->log_class, "Try to read perfmon events from %s",
+		  json_filename);
+
+  error = unix_proc_file_contents ((char *) json_filename, &cp);
+
+  if (error)
+    {
+      vlib_log_err (pm->log_class,
+		    "Failed to read CPU-specific counter table");
+      vlib_log_err (pm->log_class,
+		    "Download from https://download.01.org/perfmon, "
+		    "and install as %s", json_filename);
+      vec_free (json_filename);
+      clib_error_report (error);
+      return ht;
+    }
+  vlib_log_debug (pm->log_class, "Read OK, parse the event table...");
+  vec_free (json_filename);
+
+again:
+  while (*cp)
+    {
+      switch (state)
+	{
+	case STATE_START:
+	  while (*cp && *cp != '{' && *cp != '}' && *cp != ',')
+	    cp++;
+	  if (*cp == 0)
+	    goto done;
+
+	  /* Look for a new event */
+	  if (*cp == '{')
+	    {
+	      if (*cp == 0)
+		{
+		error:
+		  clib_warning ("parse fail");
+		  hash_free (ht);
+		  return 0;
+		}
+	      cp++;
+	      state = STATE_READ_NAME;
+	      goto again;
+	    }
+	  else if (*cp == '}')	/* end of event */
+	    {
+	      /* Look for the "EventName" nvp */
+	      for (i = 0; i < vec_len (nvps); i++)
+		{
+		  nvp = nvps[i];
+		  if (!strncmp ((char *) nvp->name, "EventName", 9))
+		    {
+		      event_name = nvp->value;
+		      goto found;
+		    }
+		}
+	      /* no name? */
+	      for (i = 0; i < vec_len (nvps); i++)
+		{
+		  vec_free (nvps[i]->name);
+		  vec_free (nvps[i]->value);
+		}
+	      vec_free (nvps);
+	      cp++;
+	      goto again;
+
+	    found:
+	      event_name = downcase (event_name);
+	      hash_set_mem (ht, event_name, nvps);
+	      nvp = 0;
+	      nvps = 0;
+	      cp++;
+	      goto again;
+	    }
+	  else if (*cp == ',')	/* punctuation */
+	    {
+	      cp++;
+	      goto again;
+	    }
+
+	case STATE_READ_NAME:
+	  vec_validate (nvp, 0);
+	  v = 0;
+	  while (*cp && *cp != '"')
+	    cp++;
+
+	  if (*cp == 0)
+	    {
+	      vec_free (nvp);
+	      goto error;
+	    }
+
+	  cp++;
+	  while (*cp && *cp != '"')
+	    {
+	      vec_add1 (v, *cp);
+	      cp++;
+	    }
+	  if (*cp == 0)
+	    {
+	      vec_free (v);
+	      goto error;
+	    }
+	  cp++;
+	  vec_add1 (v, 0);
+	  nvp->name = v;
+	  state = STATE_READ_VALUE;
+	  goto again;
+
+	case STATE_READ_VALUE:
+	  while (*cp && *cp != ':')
+	    cp++;
+	  if (*cp == 0)
+	    {
+	      vec_free (nvp->name);
+	      goto error;
+	    }
+	  while (*cp && *cp != '"')
+	    cp++;
+	  if (*cp == 0)
+	    {
+	      vec_free (nvp->name);
+	      goto error;
+	    }
+	  else
+	    cp++;
+	  v = 0;
+	  while (*cp && *cp != '"')
+	    {
+	      vec_add1 (v, *cp);
+	      cp++;
+	    }
+	  if (*cp == 0)
+	    {
+	      vec_free (nvp->name);
+	      vec_free (v);
+	      goto error;
+	    }
+	  vec_add1 (v, 0);
+	  nvp->value = v;
+	  vec_add1 (nvps, nvp);
+	  while (*cp && *cp != ',' && *cp != '}')
+	    cp++;
+	  if (*cp == 0)
+	    {
+	      vec_free (nvp->name);
+	      vec_free (nvp->value);
+	      goto error;
+	    }
+	  else if (*cp == '}')
+	    state = STATE_START;
+	  else
+	    {
+	      cp++;
+	      state = STATE_READ_NAME;
+	    }
+	  nvp = 0;
+	  goto again;
+	}
+    }
+
+done:
+  return (ht);
+}
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */