src/proc_softirqs.c

   1 #ifdef HAVE_CONFIG_H
   2 #include <config.h>
   3 #endif
   4 #include <stdio.h>
   5 #include <stdlib.h>
   6 #include <string.h>
   7 #include <ctype.h>
   8
   9 #include "common.h"
  10 #include "appconfig.h"
  11 #include "procfile.h"
  12 #include "rrd.h"
  13 #include "plugin_proc.h"
  14 #include "log.h"
  15
  16 #define MAX_INTERRUPTS 256
  17 #define MAX_INTERRUPT_CPUS 256
  18 #define MAX_INTERRUPT_NAME 50
  19
  20 struct interrupt {
  21         int used;
  22         char *id;
  23         char name[MAX_INTERRUPT_NAME + 1];
  24         unsigned long long value[MAX_INTERRUPT_CPUS];
  25         unsigned long long total;
  26 };
  27
  28 static struct interrupt *alloc_interrupts(int lines) {
  29         static struct interrupt *irrs = NULL;
  30         static int alloced = 0;
  31
  32         if(lines < alloced) return irrs;
  33         else {
  34                 irrs = (struct interrupt *)realloc(irrs, lines * sizeof(struct interrupt));
  35                 if(!irrs)
  36                         fatal("Cannot allocate memory for %d interrupts", lines);
  37
  38                 alloced = lines;
  39         }
  40
  41         return irrs;
  42 }
  43
  44 int do_proc_softirqs(int update_every, unsigned long long dt) {
  45         static procfile *ff = NULL;
  46         static int cpus = -1, do_per_core = -1;
  47
  48         struct interrupt *irrs = NULL;
  49
  50         if(dt) {};
  51
  52         if(do_per_core == -1) do_per_core = config_get_boolean("plugin:proc:/proc/softirqs", "interrupts per core", 1);
  53
  54         if(!ff) {
  55                 char filename[FILENAME_MAX + 1];
  56                 snprintf(filename, FILENAME_MAX, "%s%s", global_host_prefix, "/proc/softirqs");
  57                 ff = procfile_open(config_get("plugin:proc:/proc/softirqs", "filename to monitor", filename), " \t", PROCFILE_FLAG_DEFAULT);
  58         }
  59         if(!ff) return 1;
  60
  61         ff = procfile_readall(ff);
  62         if(!ff) return 0; // we return 0, so that we will retry to open it next time
  63
  64         uint32_t lines = procfile_lines(ff), l;
  65         uint32_t words = procfile_linewords(ff, 0), w;
  66
  67         if(!lines) {
  68                 error("Cannot read /proc/softirqs, zero lines reported.");
  69                 return 1;
  70         }
  71
  72         // find how many CPUs are there
  73         if(cpus == -1) {
  74                 cpus = 0;
  75                 for(w = 0; w < words ; w++) {
  76                         if(strncmp(procfile_lineword(ff, 0, w), "CPU", 3) == 0)
  77                                 cpus++;
  78                 }
  79
  80                 if(cpus > MAX_INTERRUPT_CPUS) cpus = MAX_INTERRUPT_CPUS;
  81         }
  82
  83         if(!cpus) {
  84                 error("PLUGIN: PROC_SOFTIRQS: Cannot find the number of CPUs in /proc/softirqs");
  85                 return 1;
  86         }
  87
  88         // allocate the size we need;
  89         irrs = alloc_interrupts(lines);
  90         irrs[0].used = 0;
  91
  92         // loop through all lines
  93         for(l = 1; l < lines ;l++) {
  94                 struct interrupt *irr = &irrs[l];
  95                 irr->used = 0;
  96                 irr->total = 0;
  97
  98                 words = procfile_linewords(ff, l);
  99                 if(!words) continue;
 100
 101                 irr->id = procfile_lineword(ff, l, 0);
 102                 if(!irr->id || !irr->id[0]) continue;
 103
 104                 int idlen = strlen(irr->id);
 105                 if(irr->id[idlen - 1] == ':')
 106                         irr->id[idlen - 1] = '\0';
 107
 108                 int c;
 109                 for(c = 0; c < cpus ;c++) {
 110                         if((c + 1) < (int)words)
 111                                 irr->value[c] = strtoull(procfile_lineword(ff, l, (uint32_t)(c + 1)), NULL, 10);
 112                         else
 113                                 irr->value[c] = 0;
 114
 115                         irr->total += irr->value[c];
 116                 }
 117
 118                 strncpy(irr->name, irr->id, MAX_INTERRUPT_NAME);
 119                 irr->name[MAX_INTERRUPT_NAME] = '\0';
 120
 121                 irr->used = 1;
 122         }
 123
 124         RRDSET *st;
 125
 126         // --------------------------------------------------------------------
 127
 128         st = rrdset_find_bytype("system", "softirqs");
 129         if(!st) {
 130                 st = rrdset_create("system", "softirqs", NULL, "softirqs", NULL, "System softirqs", "softirqs/s", 950, update_every, RRDSET_TYPE_STACKED);
 131
 132                 for(l = 0; l < lines ;l++) {
 133                         if(!irrs[l].used) continue;
 134                         rrddim_add(st, irrs[l].id, irrs[l].name, 1, 1, RRDDIM_INCREMENTAL);
 135                 }
 136         }
 137         else rrdset_next(st);
 138
 139         for(l = 0; l < lines ;l++) {
 140                 if(!irrs[l].used) continue;
 141                 rrddim_set(st, irrs[l].id, irrs[l].total);
 142         }
 143         rrdset_done(st);
 144
 145         if(do_per_core) {
 146                 int c;
 147
 148                 for(c = 0; c < cpus ; c++) {
 149                         char id[256];
 150                         snprintf(id, 256, "cpu%d_softirqs", c);
 151
 152                         st = rrdset_find_bytype("cpu", id);
 153                         if(!st) {
 154                                 // find if everything is zero
 155                                 unsigned long long core_sum = 0 ;
 156                                 for(l = 0; l < lines ;l++) {
 157                                         if(!irrs[l].used) continue;
 158                                         core_sum += irrs[l].value[c];
 159                                 }
 160                                 if(core_sum == 0) continue; // try next core
 161
 162                                 char name[256], title[256];
 163                                 snprintf(name, 256, "cpu%d_softirqs", c);
 164                                 snprintf(title, 256, "CPU%d softirqs", c);
 165                                 st = rrdset_create("cpu", id, name, "softirqs", "cpu.softirqs", title, "softirqs/s", 3000 + c, update_every, RRDSET_TYPE_STACKED);
 166
 167                                 for(l = 0; l < lines ;l++) {
 168                                         if(!irrs[l].used) continue;
 169                                         rrddim_add(st, irrs[l].id, irrs[l].name, 1, 1, RRDDIM_INCREMENTAL);
 170                                 }
 171                         }
 172                         else rrdset_next(st);
 173
 174                         for(l = 0; l < lines ;l++) {
 175                                 if(!irrs[l].used) continue;
 176                                 rrddim_set(st, irrs[l].id, irrs[l].value[c]);
 177                         }
 178                         rrdset_done(st);
 179                 }
 180         }
 181
 182         return 0;
 183 }