cpupowerutils: bench - ConfigStyle bugfixes
[linux-2.6.git] / tools / power / cpupower / bench / benchmark.c
1 /*  cpufreq-bench CPUFreq microbenchmark
2  *
3  *  Copyright (C) 2008 Christian Kornacker <ckornacker@suse.de>
4  *
5  *  This program is free software; you can redistribute it and/or modify
6  *  it under the terms of the GNU General Public License as published by
7  *  the Free Software Foundation; either version 2 of the License, or
8  *  (at your option) any later version.
9  *
10  *  This program is distributed in the hope that it will be useful,
11  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
12  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  *  GNU General Public License for more details.
14  *
15  *  You should have received a copy of the GNU General Public License
16  *  along with this program; if not, write to the Free Software
17  *  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
18  */
19
20 #include <stdio.h>
21 #include <unistd.h>
22 #include <math.h>
23
24 #include "config.h"
25 #include "system.h"
26 #include "benchmark.h"
27
28 /* Print out progress if we log into a file */
29 #define show_progress(total_time, progress_time)        \
30 if (config->output != stdout) {                         \
31         fprintf(stdout, "Progress: %02lu %%\r",         \
32                 (progress_time * 100) / total_time);    \
33         fflush(stdout);                                 \
34 }
35
36 /**
37  * compute how many rounds of calculation we should do
38  * to get the given load time
39  *
40  * @param load aimed load time in ┬Ás
41  *
42  * @retval rounds of calculation
43  **/
44
45 unsigned int calculate_timespace(long load, struct config *config)
46 {
47         int i;
48         long long now, then;
49         unsigned int estimated = GAUGECOUNT;
50         unsigned int rounds = 0;
51         unsigned int timed = 0;
52
53         if (config->verbose)
54                 printf("calibrating load of %lius, please wait...\n", load);
55
56         /* get the initial calculation time for a specific number of rounds */
57         now = get_time();
58         ROUNDS(estimated);
59         then = get_time();
60
61         timed = (unsigned int)(then - now);
62
63         /* approximation of the wanted load time by comparing with the
64          * initial calculation time */
65         for (i = 0; i < 4; i++) {
66                 rounds = (unsigned int)(load * estimated / timed);
67                 dprintf("calibrating with %u rounds\n", rounds);
68                 now = get_time();
69                 ROUNDS(rounds);
70                 then = get_time();
71
72                 timed = (unsigned int)(then - now);
73                 estimated = rounds;
74         }
75         if (config->verbose)
76                 printf("calibration done\n");
77
78         return estimated;
79 }
80
81 /**
82  * benchmark
83  * generates a specific sleep an load time with the performance
84  * governor and compares the used time for same calculations done
85  * with the configured powersave governor
86  *
87  * @param config config values for the benchmark
88  *
89  **/
90
91 void start_benchmark(struct config *config)
92 {
93         unsigned int _round, cycle;
94         long long now, then;
95         long sleep_time = 0, load_time = 0;
96         long performance_time = 0, powersave_time = 0;
97         unsigned int calculations;
98         unsigned long total_time = 0, progress_time = 0;
99
100         sleep_time = config->sleep;
101         load_time = config->load;
102
103         /* For the progress bar */
104         for (_round = 1; _round <= config->rounds; _round++)
105                 total_time += _round * (config->sleep + config->load);
106         total_time *= 2; /* powersave and performance cycles */
107
108         for (_round = 0; _round < config->rounds; _round++) {
109                 performance_time = 0LL;
110                 powersave_time = 0LL;
111
112                 show_progress(total_time, progress_time);
113
114                 /* set the cpufreq governor to "performance" which disables
115                  * P-State switching. */
116                 if (set_cpufreq_governor("performance", config->cpu) != 0)
117                         return;
118
119                 /* calibrate the calculation time. the resulting calculation
120                  * _rounds should produce a load which matches the configured
121                  * load time */
122                 calculations = calculate_timespace(load_time, config);
123
124                 if (config->verbose)
125                         printf("_round %i: doing %u cycles with %u calculations"
126                                " for %lius\n", _round + 1, config->cycles,
127                                calculations, load_time);
128
129                 fprintf(config->output, "%u %li %li ",
130                         _round, load_time, sleep_time);
131
132                 if (config->verbose)
133                         printf("avarage: %lius, rps:%li\n",
134                                 load_time / calculations,
135                                 1000000 * calculations / load_time);
136
137                 /* do some sleep/load cycles with the performance governor */
138                 for (cycle = 0; cycle < config->cycles; cycle++) {
139                         now = get_time();
140                         usleep(sleep_time);
141                         ROUNDS(calculations);
142                         then = get_time();
143                         performance_time += then - now - sleep_time;
144                         if (config->verbose)
145                                 printf("performance cycle took %lius, "
146                                         "sleep: %lius, "
147                                         "load: %lius, rounds: %u\n",
148                                         (long)(then - now), sleep_time,
149                                         load_time, calculations);
150                 }
151                 fprintf(config->output, "%li ",
152                         performance_time / config->cycles);
153
154                 progress_time += sleep_time + load_time;
155                 show_progress(total_time, progress_time);
156
157                 /* set the powersave governor which activates P-State switching
158                  * again */
159                 if (set_cpufreq_governor(config->governor, config->cpu) != 0)
160                         return;
161
162                 /* again, do some sleep/load cycles with the
163                  * powersave governor */
164                 for (cycle = 0; cycle < config->cycles; cycle++) {
165                         now = get_time();
166                         usleep(sleep_time);
167                         ROUNDS(calculations);
168                         then = get_time();
169                         powersave_time += then - now - sleep_time;
170                         if (config->verbose)
171                                 printf("powersave cycle took %lius, "
172                                         "sleep: %lius, "
173                                         "load: %lius, rounds: %u\n",
174                                         (long)(then - now), sleep_time,
175                                         load_time, calculations);
176                 }
177
178                 progress_time += sleep_time + load_time;
179
180                 /* compare the avarage sleep/load cycles  */
181                 fprintf(config->output, "%li ",
182                         powersave_time / config->cycles);
183                 fprintf(config->output, "%.3f\n",
184                         performance_time * 100.0 / powersave_time);
185                 fflush(config->output);
186
187                 if (config->verbose)
188                         printf("performance is at %.2f%%\n",
189                                 performance_time * 100.0 / powersave_time);
190
191                 sleep_time += config->sleep_step;
192                 load_time += config->load_step;
193         }
194 }