xencpu plugin: Plugin to collect CPU load under Xen

  Fixed remarks of code review:
  * Removed static pointer initialization
  * Tabs replaced by spaces
  * Added check for xenctrl.h
  * Changed order of libraries check, added argument quotes
  * Added plugin documentation

diff --git a/configure.ac b/configure.ac
index 68db42b..5713595 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -4709,6 +4709,46 @@ then
 fi
 # }}}
 
+# --with-libxenctrl {{{
+with_libxenctrl_cppflags=""
+with_libxenctrl_ldflags=""
+AC_ARG_WITH(libxenctrl, [AS_HELP_STRING([--with-libxenctrl@<:@=PREFIX@:>@], [Path to libxenctrl.])],
+[
+       if test "x$withval" != "xno" && test "x$withval" != "xyes"
+       then
+               with_libxenctrl_cppflags="-I$withval/include"
+               with_libxenctrl_ldflags="-L$withval/lib"
+               with_libxenctrl="yes"
+       else
+               with_libxenctrl="$withval"
+       fi
+],
+[
+       with_libxenctrl="yes"
+])
+if test "x$with_libxenctrl" = "xyes"
+then
+       SAVE_CPPFLAGS="$CPPFLAGS"
+       CPPFLAGS="$CPPFLAGS $with_libxenctrl_cppflags"
+
+       AC_CHECK_HEADERS(xenctrl.h, [with_libxenctrl="yes"], [with_libxenctrl="no (xenctrl.h not found)"])
+
+       CPPFLAGS="$SAVE_CPPFLAGS"
+fi
+if test "x$with_libxenctrl" = "xyes"
+then
+       SAVE_CPPFLAGS="$CPPFLAGS"
+       SAVE_LDFLAGS="$LDFLAGS"
+       CPPFLAGS="$CPPFLAGS $with_libxenctrl_cppflags"
+       LDFLAGS="$LDFLAGS $with_libxenctrl_ldflags"
+
+       #Xen versions older than 3.4 has no xc_getcpuinfo()
+       AC_CHECK_LIB(xenctrl, xc_getcpuinfo, [with_libxenctrl="yes"], [with_libxenctrl="no (symbol 'xc_getcpuinfo' not found)"], [])
+
+       CPPFLAGS="$SAVE_CPPFLAGS"
+       LDFLAGS="$SAVE_LDFLAGS"
+fi
+
 # --with-libxmms {{{
 with_xmms_config="xmms-config"
 with_xmms_cflags=""
@@ -5407,6 +5447,7 @@ plugin_virt="no"
 plugin_vmem="no"
 plugin_vserver="no"
 plugin_wireless="no"
+plugin_xencpu="no"
 plugin_zfs_arc="no"
 plugin_zone="no"
 plugin_zookeeper="no"
@@ -5738,6 +5779,10 @@ then
        plugin_virt="yes"
 fi
 
+if test "x$with_libxenctrl" = "xyes"
+then
+  plugin_xencpu="yes"
+fi
 
 m4_divert_once([HELP_ENABLE], [
 collectd plugins:])
@@ -5893,6 +5938,7 @@ AC_PLUGIN([write_redis],         [$with_libhiredis],        [Redis output plugin
 AC_PLUGIN([write_riemann],       [$with_riemann_c],         [Riemann output plugin])
 AC_PLUGIN([write_sensu],         [yes],                     [Sensu output plugin])
 AC_PLUGIN([write_tsdb],          [yes],                     [TSDB output plugin])
+AC_PLUGIN([xencpu],              [$plugin_xencpu],          [Xen Host CPU usage])
 AC_PLUGIN([xmms],                [$with_libxmms],           [XMMS statistics])
 AC_PLUGIN([zfs_arc],             [$plugin_zfs_arc],         [ZFS ARC statistics])
 AC_PLUGIN([zone],                [$plugin_zone],            [Solaris container statistics])
@@ -6144,6 +6190,7 @@ Configuration:
     libupsclient  . . . . $with_libupsclient
     libvarnish  . . . . . $with_libvarnish
     libvirt . . . . . . . $with_libvirt
+    libxenctrl  . . . . . $with_libxenctrl
     libxml2 . . . . . . . $with_libxml2
     libxmms . . . . . . . $with_libxmms
     libyajl . . . . . . . $with_libyajl
@@ -6293,6 +6340,7 @@ Configuration:
     write_riemann . . . . $enable_write_riemann
     write_sensu . . . . . $enable_write_sensu
     write_tsdb  . . . . . $enable_write_tsdb
+    xencpu  . . . . . . . $enable_xencpu
     xmms  . . . . . . . . $enable_xmms
     zfs_arc . . . . . . . $enable_zfs_arc
     zone  . . . . . . . . $enable_zone

diff --git a/src/Makefile.am b/src/Makefile.am
index 1e3dfba..3683b55 100644 (file)
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -1277,6 +1277,13 @@ write_tsdb_la_SOURCES = write_tsdb.c
 write_tsdb_la_LDFLAGS = $(PLUGIN_LDFLAGS)
 endif
 
+if BUILD_PLUGIN_XENCPU
+pkglib_LTLIBRARIES += xencpu.la
+xencpu_la_SOURCES = xencpu.c
+xencpu_la_LDFLAGS = $(PLUGIN_LDFLAGS)
+xencpu_la_LIBADD = -lxenctrl
+endif
+
 if BUILD_PLUGIN_XMMS
 pkglib_LTLIBRARIES += xmms.la
 xmms_la_SOURCES = xmms.c

diff --git a/src/collectd.conf.in b/src/collectd.conf.in
index 41d10ee..80a7db9 100644 (file)
--- a/src/collectd.conf.in
+++ b/src/collectd.conf.in
@@ -206,6 +206,7 @@
 #@BUILD_PLUGIN_WRITE_RIEMANN_TRUE@LoadPlugin write_riemann
 #@BUILD_PLUGIN_WRITE_SENSU_TRUE@LoadPlugin write_sensu
 #@BUILD_PLUGIN_WRITE_TSDB_TRUE@LoadPlugin write_tsdb
+#@BUILD_PLUGIN_XENCPU_TRUE@LoadPlugin xencpu
 #@BUILD_PLUGIN_XMMS_TRUE@LoadPlugin xmms
 #@BUILD_PLUGIN_ZFS_ARC_TRUE@LoadPlugin zfs_arc
 #@BUILD_PLUGIN_ZONE_TRUE@LoadPlugin zone

diff --git a/src/collectd.conf.pod b/src/collectd.conf.pod
index 3f2b2ef..c72d64a 100644 (file)
--- a/src/collectd.conf.pod
+++ b/src/collectd.conf.pod
@@ -8077,6 +8077,14 @@ attribute for each metric being sent out to I<Sensu>.
 
 =back
 
+=head2 Plugin C<xencpu>
+
+This plugin collects metrics of hardware CPU load for machine running Xen
+hypervisor. Load is calculated from 'idle time' value, provided by Xen.
+Result is reported using the C<percent> type, for each CPU (core).
+
+This plugin doesn't have any options (yet).
+
 =head2 Plugin C<zookeeper>
 
 The I<zookeeper plugin> will collect statistics from a I<Zookeeper> server

diff --git a/src/xencpu.c b/src/xencpu.c
new file mode 100644 (file)
index 0000000..2b87235
--- /dev/null
+++ b/src/xencpu.c
@@ -0,0 +1,163 @@
+/**
+ * collectd - src/xencpu.c
+ * Copyright (C) 2016       Pavel Rochnyak
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; only version 2 of the License is applicable.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
+ *
+ * Authors:
+ *   Pavel Rochnyak <pavel2000 ngs.ru>
+ **/
+
+#include "collectd.h"
+#include "common.h"
+#include "plugin.h"
+
+#include <xenctrl.h>
+
+#ifdef XENCTRL_HAS_XC_INTERFACE
+
+//Xen-4.1+
+#define XC_INTERFACE_INIT_ARGS NULL,NULL,0
+xc_interface *xc_handle;
+
+#else /* XENCTRL_HAS_XC_INTERFACE */
+
+//For xen-3.4/xen-4.0
+#include <string.h>
+#define xc_strerror(xc_interface, errcode) strerror(errcode)
+#define XC_INTERFACE_INIT_ARGS
+typedef int xc_interface;
+xc_interface xc_handle = 0;
+
+#endif /* XENCTRL_HAS_XC_INTERFACE */
+
+uint32_t num_cpus = 0;
+xc_cpuinfo_t *cpu_info;
+static value_to_rate_state_t *cpu_states;
+
+static int xencpu_init (void)
+{
+    xc_handle = xc_interface_open(XC_INTERFACE_INIT_ARGS);
+    if (!xc_handle)
+    {
+        ERROR ("xencpu: xc_interface_open() failed");
+        return (-1);
+    };
+
+    xc_physinfo_t *physinfo;
+
+    physinfo = calloc(1, sizeof(xc_physinfo_t));
+    if (physinfo == NULL)
+    {
+        ERROR ("xencpu plugin: calloc() for physinfo failed.");
+        xc_interface_close(xc_handle);
+        return (ENOMEM);
+    }
+
+    if (xc_physinfo(xc_handle, physinfo) < 0)
+    {
+        ERROR ("xencpu plugin: xc_physinfo() failed");
+        xc_interface_close(xc_handle);
+        free(physinfo);
+        return (-1);
+    };
+
+    num_cpus = physinfo->nr_cpus;
+    free(physinfo);
+
+    INFO ("xencpu plugin: Found %"PRIu32" processors.", num_cpus);
+
+    cpu_info = calloc(num_cpus, sizeof(xc_cpuinfo_t));
+    if (cpu_info == NULL)
+    {
+        ERROR ("xencpu plugin: calloc() for num_cpus failed.");
+        xc_interface_close(xc_handle);
+        return (ENOMEM);
+    }
+
+    cpu_states = calloc (num_cpus, sizeof (value_to_rate_state_t));
+    if (cpu_states == NULL)
+    {
+        ERROR ("xencpu plugin: calloc() for cpu_states failed.");
+        xc_interface_close(xc_handle);
+        free(cpu_info);
+        return (ENOMEM);
+    }
+
+    return (0);
+} /* static int xencpu_init */
+
+static int xencpu_shutdown (void)
+{
+    free(cpu_states);
+    free(cpu_info);
+    xc_interface_close(xc_handle);
+
+    return 0;
+} /* static int xencpu_shutdown */
+
+static void submit_value (int cpu_num, gauge_t percent)
+{
+    value_t values[1];
+    value_list_t vl = VALUE_LIST_INIT;
+
+    values[0].gauge = percent;
+
+    vl.values = values;
+    vl.values_len = 1;
+
+    sstrncpy (vl.host, hostname_g, sizeof (vl.host));
+    sstrncpy (vl.plugin, "xencpu", sizeof (vl.plugin));
+    sstrncpy (vl.type, "percent", sizeof (vl.type));
+    sstrncpy (vl.type_instance, "load", sizeof (vl.type_instance));
+
+    if (cpu_num >= 0) {
+        ssnprintf (vl.plugin_instance, sizeof (vl.plugin_instance),
+                "%i", cpu_num);
+    }
+    plugin_dispatch_values (&vl);
+} /* static void submit_value */
+
+static int xencpu_read (void)
+{
+    cdtime_t now = cdtime ();
+
+    int rc, nr_cpus;
+
+    rc = xc_getcpuinfo(xc_handle, num_cpus, cpu_info, &nr_cpus);
+    if (rc < 0) {
+        ERROR ("xencpu: xc_getcpuinfo() Failed: %d %s\n", rc, xc_strerror(xc_handle,errno));
+        return (-1);
+    }
+
+    int cpu, status;
+    for (cpu = 0; cpu < nr_cpus; cpu++) {
+        gauge_t rate = NAN;
+        value_t value = {.derive = cpu_info[cpu].idletime};
+
+        status = value_to_rate (&rate, value, DS_TYPE_DERIVE, now, &cpu_states[cpu]);
+        if (status == 0) {
+            submit_value(cpu, 100 - rate/10000000);
+        }
+    }
+
+    return (0);
+} /* static int xencpu_read */
+
+void module_register (void)
+{
+    plugin_register_init ("xencpu", xencpu_init);
+    plugin_register_read ("xencpu", xencpu_read);
+    plugin_register_shutdown ("xencpu", xencpu_shutdown);
+} /* void module_register */