blob: eede03391be9c03d90b85a6246c6532c95183ddf [file] [log] [blame]
/*
* stats.c -- Statistics helpers
*
* Copyright (C) 2004 Henrique de Moraes Holschuh <hmh@debian.org>
*
* 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; either version 2 of the License, or
* (at your option) any later version.
*
* 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#define _GNU_SOURCE
#ifndef HAVE_CONFIG_H
#error Invalid or missing autoconf build environment
#endif
#include "rng-tools-config.h"
#include <unistd.h>
#include <stdint.h>
#include <stdio.h>
#include <sys/time.h>
#include <time.h>
#include <string.h>
#include "fips.h"
#include "stats.h"
static char stat_prefix[20] = "";
void set_stat_prefix(const char* prefix)
{
stat_prefix[sizeof(stat_prefix)-1] = 0;
strncpy(stat_prefix, prefix, sizeof(stat_prefix)-1);
}
static void scale_mult_unit(char *unit, int unitsize,
const char *baseunit,
double *value_min,
double *value_avg,
double *value_max)
{
int mult = 0;
char multchar[] = "KMGTPE";
while ((*value_min >= 1024.0) && (*value_avg >= 1024.0) &&
(*value_max >= 1024.0) && (mult < sizeof(multchar))) {
mult++;
*value_min = *value_min / 1024.0;
*value_max = *value_max / 1024.0;
*value_avg = *value_avg / 1024.0;
}
unit[unitsize-1] = 0;
if (mult)
snprintf(unit, unitsize, "%ci%s", multchar[mult-1], baseunit);
else
strncpy(unit, baseunit, unitsize);
}
/* Computes elapsed time in microseconds */
uint64_t elapsed_time(struct timeval *start,
struct timeval *stop)
{
uint64_t diff;
if (stop->tv_sec < start->tv_sec) return 0;
diff = (stop->tv_sec - start->tv_sec) * 1000000ULL;
if (stop->tv_usec > start->tv_usec) {
diff += stop->tv_usec - start->tv_usec;
} else {
diff -= start->tv_usec - stop->tv_usec;
}
return diff;
}
/* Updates min-max stat */
void update_stat(struct rng_stat *stat, uint64_t value)
{
uint64_t overflow = stat->num_samples;
if ((stat->min == 0 ) || (value < stat->min)) stat->min = value;
if (value > stat->max) stat->max = value;
if (++stat->num_samples > overflow) {
stat->sum += value;
} else {
stat->sum = value;
stat->num_samples = 1;
}
}
char *dump_stat_counter(char *buf, int size,
const char *msg, uint64_t value)
{
buf[size-1] = 0;
snprintf(buf, size-1, "%s%s: %llu", stat_prefix, msg,
(unsigned long long) value);
return buf;
}
char *dump_stat_stat(char *buf, int size,
const char *msg, const char *unit, struct rng_stat *stat)
{
double avg = 0.0;
if (stat->num_samples > 0)
avg = (double)stat->sum / stat->num_samples;
buf[size-1] = 0;
snprintf(buf, size-1, "%s%s: (min=%llu; avg=%.3f; max=%llu)%s",
stat_prefix, msg, (unsigned long long) stat->min, avg,
(unsigned long long) stat->max, unit);
return buf;
}
char *dump_stat_bw(char *buf, int size,
const char *msg, const char *unit,
struct rng_stat *stat,
uint64_t blocksize)
{
char unitscaled[20];
double bw_avg = 0.0, bw_min = 0.0, bw_max = 0.0;
if (stat->max > 0)
bw_min = (1000000.0 * blocksize) / stat->max;
if (stat->min > 0)
bw_max = (1000000.0 * blocksize) / stat->min;
if (stat->num_samples > 0)
bw_avg = (1000000.0 * blocksize * stat->num_samples) / stat->sum;
scale_mult_unit(unitscaled, sizeof(unitscaled), unit,
&bw_min, &bw_avg, &bw_max);
buf[size-1] = 0;
snprintf(buf, size-1, "%s%s: (min=%.3f; avg=%.3f; max=%.3f)%s/s",
stat_prefix, msg, bw_min, bw_avg, bw_max, unitscaled);
return buf;
}