tools/gator/daemon/KMod.cpp

   1 /**
   2  * Copyright (C) ARM Limited 2013-2015. All rights reserved.
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License version 2 as
   6  * published by the Free Software Foundation.
   7  */
   8
   9 #include "KMod.h"
  10
  11 #include <sys/types.h>
  12 #include <dirent.h>
  13 #include <unistd.h>
  14
  15 #include "ConfigurationXML.h"
  16 #include "Counter.h"
  17 #include "DriverSource.h"
  18 #include "Logging.h"
  19 #include "SessionData.h"
  20
  21 // Claim all the counters in /dev/gator/events
  22 bool KMod::claimCounter(const Counter &counter) const {
  23         char text[128];
  24         snprintf(text, sizeof(text), "/dev/gator/events/%s", counter.getType());
  25         return access(text, F_OK) == 0;
  26 }
  27
  28 void KMod::resetCounters() {
  29         char base[128];
  30         char text[128];
  31
  32         // Initialize all perf counters in the driver, i.e. set enabled to zero
  33         struct dirent *ent;
  34         DIR* dir = opendir("/dev/gator/events");
  35         if (dir) {
  36                 while ((ent = readdir(dir)) != NULL) {
  37                         // skip hidden files, current dir, and parent dir
  38                         if (ent->d_name[0] == '.')
  39                                 continue;
  40                         snprintf(base, sizeof(base), "/dev/gator/events/%s", ent->d_name);
  41                         snprintf(text, sizeof(text), "%s/enabled", base);
  42                         DriverSource::writeDriver(text, 0);
  43                         snprintf(text, sizeof(text), "%s/count", base);
  44                         DriverSource::writeDriver(text, 0);
  45                 }
  46                 closedir(dir);
  47         }
  48 }
  49
  50 static const char ARM_MALI_MIDGARD[] = "ARM_Mali-Midgard_";
  51 static const char ARM_MALI_T[] = "ARM_Mali-T";
  52
  53 void KMod::setupCounter(Counter &counter) {
  54         char base[128];
  55         char text[128];
  56         snprintf(base, sizeof(base), "/dev/gator/events/%s", counter.getType());
  57
  58         if ((strncmp(counter.getType(), ARM_MALI_MIDGARD, sizeof(ARM_MALI_MIDGARD) - 1) == 0 ||
  59              strncmp(counter.getType(), ARM_MALI_T, sizeof(ARM_MALI_T) - 1) == 0)) {
  60                 mIsMaliCapture = true;
  61         }
  62
  63         snprintf(text, sizeof(text), "%s/enabled", base);
  64         int enabled = true;
  65         if (DriverSource::writeReadDriver(text, &enabled) || !enabled) {
  66                 counter.setEnabled(false);
  67                 return;
  68         }
  69
  70         int value = 0;
  71         snprintf(text, sizeof(text), "%s/key", base);
  72         DriverSource::readIntDriver(text, &value);
  73         counter.setKey(value);
  74
  75         snprintf(text, sizeof(text), "%s/cores", base);
  76         if (DriverSource::readIntDriver(text, &value) == 0) {
  77                 counter.setCores(value);
  78         }
  79
  80         snprintf(text, sizeof(text), "%s/event", base);
  81         DriverSource::writeDriver(text, counter.getEvent());
  82         snprintf(text, sizeof(text), "%s/count", base);
  83         if (access(text, F_OK) == 0) {
  84                 int count = counter.getCount();
  85                 if (DriverSource::writeReadDriver(text, &count) && counter.getCount() > 0) {
  86                         logg->logError("Cannot enable EBS for %s:%i with a count of %d\n", counter.getType(), counter.getEvent(), counter.getCount());
  87                         handleException();
  88                 }
  89                 counter.setCount(count);
  90         } else if (counter.getCount() > 0) {
  91                 ConfigurationXML::remove();
  92                 logg->logError("Event Based Sampling is only supported with kernel versions 3.0.0 and higher with CONFIG_PERF_EVENTS=y, and CONFIG_HW_PERF_EVENTS=y. The invalid configuration.xml has been removed.\n");
  93                 handleException();
  94         }
  95 }
  96
  97 int KMod::writeCounters(mxml_node_t *root) const {
  98         struct dirent *ent;
  99         mxml_node_t *counter;
 100
 101         // counters.xml is simply a file listing of /dev/gator/events
 102         DIR* dir = opendir("/dev/gator/events");
 103         if (dir == NULL) {
 104                 return 0;
 105         }
 106
 107         int count = 0;
 108         while ((ent = readdir(dir)) != NULL) {
 109                 // skip hidden files, current dir, and parent dir
 110                 if (ent->d_name[0] == '.')
 111                         continue;
 112                 counter = mxmlNewElement(root, "counter");
 113                 mxmlElementSetAttr(counter, "name", ent->d_name);
 114                 ++count;
 115         }
 116         closedir(dir);
 117
 118         return count;
 119 }