X-Git-Url: https://git.octo.it/?a=blobdiff_plain;f=src%2Fturbostat.c;h=9465ddc0f168436d1c52265036b8aaab0b795bbf;hb=950876683f3b214072e9295cee21999ed726cd83;hp=31d458db9481652e532a04f287b6c5944b4ed29a;hpb=8b039e3d6d460b149630044973514677c9f17475;p=collectd.git

diff --git a/src/turbostat.c b/src/turbostat.c
index 31d458db..9465ddc0 100644
--- a/src/turbostat.c
+++ b/src/turbostat.c
@@ -37,8 +37,8 @@
 
 #include "collectd.h"
 
-#include "common.h"
 #include "plugin.h"
+#include "utils/common/common.h"
 #include "utils_time.h"
 
 #include "msr-index.h"
@@ -49,6 +49,14 @@
 
 #define PLUGIN_NAME "turbostat"
 
+typedef enum affinity_policy_enum {
+  policy_restore_affinity, /* restore cpu affinity to whatever it was before */
+  policy_allcpus_affinity  /* do not restore affinity, set to all cpus */
+} affinity_policy_t;
+
+/* the default is to set cpu affinity to all cpus */
+static affinity_policy_t affinity_policy = policy_allcpus_affinity;
+
 /*
  * This tool uses the Model-Specific Registers (MSRs) present on Intel
  * processors.
@@ -244,6 +252,7 @@ static const char *config_keys[] = {
     "TCCActivationTemp",
     "RunningAveragePowerLimit",
     "LogicalCoreNames",
+    "RestoreAffinityPolicy",
 };
 static const int config_keys_num = STATIC_ARRAY_SIZE(config_keys);
 
@@ -1425,9 +1434,9 @@ static void free_all_buffers(void) {
   package_delta = NULL;
 }
 
-/**********************
- * Collectd functions *
- **********************/
+  /**********************
+   * Collectd functions *
+   **********************/
 
 #define DO_OR_GOTO_ERR(something)                                              \
   do {                                                                         \
@@ -1454,9 +1463,32 @@ err:
   return ret;
 }
 
+static int save_affinity(void) {
+  if (affinity_policy == policy_restore_affinity) {
+    /* Try to save the scheduling affinity, as it will be modified by
+     * get_counters().
+     */
+    if (sched_getaffinity(0, cpu_saved_affinity_setsize,
+                          cpu_saved_affinity_set) != 0)
+      return -1;
+  }
+
+  return 0;
+}
+
+static void restore_affinity(void) {
+  /* Let's restore the affinity to the value saved in save_affinity */
+  if (affinity_policy == policy_restore_affinity)
+    (void)sched_setaffinity(0, cpu_saved_affinity_setsize,
+                            cpu_saved_affinity_set);
+  else {
+    /* reset the affinity to all present cpus */
+    (void)sched_setaffinity(0, cpu_present_setsize, cpu_present_set);
+  }
+}
+
 static int turbostat_read(void) {
   int ret;
-  int sched_getaffinity_ret;
 
   if (!allocated) {
     if ((ret = setup_all_buffers()) < 0)
@@ -1474,12 +1506,11 @@ static int turbostat_read(void) {
     }
   }
 
-  /* Try to save the scheduling affinity, as it will be modified by
-   * get_counters. If the call is unsuccessfull, this will be handled later
-   * on by restoring affinity to cpu_present_set instead.
-   */
-  sched_getaffinity_ret = sched_getaffinity(0, cpu_saved_affinity_setsize,
-                        cpu_saved_affinity_set);
+  if (save_affinity() != 0) {
+    ERROR("turbostat plugin: Unable to save the CPU affinity. Please read the "
+          "docs about RestoreAffinityPolicy option.");
+    return -1;
+  }
 
   if (!initialized) {
     if ((ret = for_all_cpus(get_counters, EVEN_COUNTERS)) < 0)
@@ -1514,21 +1545,8 @@ static int turbostat_read(void) {
   }
   ret = 0;
 out:
-  /*
-   * Let's restore the affinity
-   * This might fail if the number of CPU changed, but we can't do anything in
-   * that case..
-   */
-  if (sched_getaffinity_ret == 0) 
-    (void)sched_setaffinity(0, cpu_saved_affinity_setsize,
-                            cpu_saved_affinity_set);
-  else {
-    /*
-     * The previous call to sched_getaffinity() failed, so
-     * reset the affinity to all present cpus.
-     */
-    (void)sched_setaffinity(0, cpu_present_setsize, cpu_present_set);
-  }
+  restore_affinity();
+
   return ret;
 }
 
@@ -1645,6 +1663,15 @@ static int turbostat_config(const char *key, const char *value) {
       return -1;
     }
     tcc_activation_temp = (unsigned int)tmp_val;
+  } else if (strcasecmp("RestoreAffinityPolicy", key) == 0) {
+    if (strcasecmp("Restore", value) == 0)
+      affinity_policy = policy_restore_affinity;
+    else if (strcasecmp("AllCPUs", value) == 0)
+      affinity_policy = policy_allcpus_affinity;
+    else {
+      ERROR("turbostat plugin: Invalid RestoreAffinityPolicy '%s'", value);
+      return -1;
+    }
   } else {
     ERROR("turbostat plugin: Invalid configuration option '%s'", key);
     return -1;