1 /******************************************************************************/
2 /* */
3 /* Copyright (c) International Business Machines Corp., 2007 */
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 */
13 /* the 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */
18 /* */
19 /******************************************************************************/
20
21 /******************************************************************************/
22 /* */
23 /* File: cpuctl_test01.c */
24 /* */
25 /* Description: This is a c program that tests the cpucontroller fairness of */
26 /* scheduling the tasks according to their group shares. This */
27 /* testcase tests the ability of the cpu controller to provide */
28 /* fairness for share values (absolute). */
29 /* */
30 /* Total Tests: 3 */
31 /* */
32 /* Test 01: Tests if fairness persists among different runs */
33 /* Test 02: Tests fairness with respect to absolute share values */
34 /* Test 03: Granularity test with respect to shares values */
35 /* */
36 /* Test Name: cpu_controller_test01 */
37 /* */
38 /* Test Assertion */
39 /* Please refer to the file cpuctl_testplan.txt */
40 /* */
41 /* Author: Sudhir Kumar skumar@linux.vnet.ibm.com */
42 /* */
43 /* History: */
44 /* Created- 20/12/2007 -Sudhir Kumar <skumar@linux.vnet.ibm.com> */
45 /* */
46 /******************************************************************************/
47
48 #include <unistd.h>
49 #include <math.h>
50 #include <signal.h>
51 #include <stdio.h>
52 #include <stdlib.h>
53 #include <string.h>
54 #include <sys/resource.h>
55 #include <sys/syscall.h>
56 #include <sys/time.h>
57 #include <sys/types.h>
58 #include <sys/stat.h>
59 #include <fcntl.h>
60 #include <time.h>
61 #include <unistd.h>
62
63 #include "../libcontrollers/libcontrollers.h"
64 #include "test.h" /* LTP harness APIs */
65
66 #define TIME_INTERVAL 30 /* Time interval in seconds */
67 #define NUM_INTERVALS 3 /* How many iterations of TIME_INTERVAL */
68 #define NUM_SETS 4 /* How many share values (with same ratio) */
69 #define MULTIPLIER 10 /* decides the rate at which share value gets multiplied */
70 #define GRANULARITY 5 /* % value by which shares of a group changes */
71 char *TCID = "cpuctl_test01";
72 int TST_TOTAL = 1;
73 pid_t scriptpid;
74 char path[] = "/dev/cpuctl";
cleanup()75 extern void cleanup()
76 {
77 kill(scriptpid, SIGUSR1); /* Inform the shell to do cleanup */
78 tst_exit(); /* Report exit status */
79 }
80
81 volatile int timer_expired = 0;
82
main(int argc,char * argv[])83 int main(int argc, char *argv[])
84 {
85
86 int num_cpus;
87 int test_num;
88 int len; /* Total time = TIME_INTERVAL *num_cpus in the machine */
89 char mygroup[FILENAME_MAX], mytaskfile[FILENAME_MAX];
90 char mysharesfile[FILENAME_MAX], ch;
91 pid_t pid;
92 gid_t my_group_num; /* A number attached with a group */
93 int fd; /* A descriptor to open a fifo for synchronized start */
94 int first_counter = 0; /* To take n number of readings */
95 int second_counter = 0; /* To track number of times the base value of shares has been changed */
96 double total_cpu_time, /* Accumulated cpu time */
97 delta_cpu_time, /* Time the task could run on cpu(s) (in an interval) */
98 prev_cpu_time = 0;
99 double exp_cpu_time; /* Expected time in % as obtained by shares calculation */
100 struct rusage cpu_usage;
101 time_t current_time, prev_time, delta_time;
102 unsigned long int myshares = 2, baseshares = 1000; /* Simply the base value to start with */
103 unsigned int fmyshares, num_tasks; /* f-> from file. num_tasks is tasks in this group */
104 struct sigaction newaction, oldaction;
105
106 my_group_num = -1;
107 num_cpus = 0;
108 test_num = 0;
109
110 /* Signal handling for alarm */
111 sigemptyset(&newaction.sa_mask);
112 newaction.sa_handler = signal_handler_alarm;
113 newaction.sa_flags = 0;
114 sigaction(SIGALRM, &newaction, &oldaction);
115
116 /* Check if all parameters passed are correct */
117 if ((argc < 5) || ((my_group_num = atoi(argv[1])) <= 0)
118 || ((scriptpid = atoi(argv[3])) <= 0)
119 || ((num_cpus = atoi(argv[4])) <= 0)
120 || (test_num = atoi(argv[5])) <= 0) {
121 tst_brkm(TBROK, cleanup, "Invalid input parameters\n");
122 }
123
124 if (test_num == 1) /* Test 01 & Test 02 */
125 myshares *= my_group_num;
126 else if (test_num == 3) /* Test 03 */
127 myshares = baseshares;
128 else {
129 tst_brkm(TBROK, cleanup,
130 "Wrong Test number passed. Exiting Test...\n");
131 }
132
133 sprintf(mygroup, "%s", argv[2]);
134 sprintf(mytaskfile, "%s", mygroup);
135 sprintf(mysharesfile, "%s", mygroup);
136 strcat(mytaskfile, "/tasks");
137 strcat(mysharesfile, "/cpu.shares");
138 pid = getpid();
139 write_to_file(mytaskfile, "a", pid); /* Assign the task to it's group */
140 write_to_file(mysharesfile, "w", myshares);
141
142 fd = open("./myfifo", 0);
143 if (fd == -1) {
144 tst_brkm(TBROK, cleanup,
145 "Could not open fifo for synchronization");
146 }
147
148 fprintf(stdout, "\ntask-%d SHARES=%lu\n", my_group_num, myshares);
149 read(fd, &ch, 1); /* To block all tasks here and fire them up at the same time */
150
151 /*
152 * We now calculate the expected % cpu time of this task by getting
153 * it's group's shares, the total shares of all the groups and the
154 * number of tasks in this group.
155 */
156 FLAG = 0;
157 total_shares = 0;
158 shares_pointer = &total_shares;
159 len = strlen(path);
160 if (!strncpy(fullpath, path, len))
161 tst_brkm(TBROK, cleanup, "Could not copy directory path %s ",
162 path);
163
164 if (scan_shares_files(shares_pointer) != 0)
165 tst_brkm(TBROK, cleanup,
166 "From function scan_shares_files in %s ", fullpath);
167
168 /* return val: -1 in case of function error, else 2 is min share value */
169 if ((fmyshares = read_shares_file(mysharesfile)) < 2)
170 tst_brkm(TBROK, cleanup, "in reading shares files %s ",
171 mysharesfile);
172
173 if ((read_file(mytaskfile, GET_TASKS, &num_tasks)) < 0)
174 tst_brkm(TBROK, cleanup, "in reading tasks files %s ",
175 mytaskfile);
176
177 exp_cpu_time = (double)(fmyshares * 100) / (total_shares * num_tasks);
178
179 prev_time = time(NULL); /* Note down the time */
180
181 while (1) {
182 /* Need to run some cpu intensive task, which also frequently checks the timer value */
183 double f = 274.345, mytime; /*just a float number to take sqrt */
184 alarm(TIME_INTERVAL);
185 timer_expired = 0;
186 while (!timer_expired) /* Let the task run on cpu for TIME_INTERVAL */
187 f = sqrt(f * f); /* Time of this operation should not be high otherwise we can
188 * exceed the TIME_INTERVAL to measure cpu usage
189 */
190 current_time = time(NULL);
191 delta_time = current_time - prev_time; /* Duration in case its not exact TIME_INTERVAL */
192
193 getrusage(0, &cpu_usage);
194 total_cpu_time = (cpu_usage.ru_utime.tv_sec + cpu_usage.ru_utime.tv_usec * 1e-6 + /*user */
195 cpu_usage.ru_stime.tv_sec + cpu_usage.ru_stime.tv_usec * 1e-6); /*sys */
196 delta_cpu_time = total_cpu_time - prev_cpu_time;
197
198 prev_cpu_time = total_cpu_time;
199 prev_time = current_time;
200
201 /* calculate % cpu time each task gets */
202 if (delta_time > TIME_INTERVAL)
203 mytime =
204 (delta_cpu_time * 100) / (delta_time * num_cpus);
205 else
206 mytime =
207 (delta_cpu_time * 100) / (TIME_INTERVAL * num_cpus);
208
209 fprintf(stdout, "task-%d:CPU TIME{calc:-%6.2f(s)i.e. %6.2f(%%) exp:-%6.2f(%%)}\
210 with %lu(shares) in %lu (s) INTERVAL\n", my_group_num, delta_cpu_time, mytime,
211 exp_cpu_time, myshares, delta_time);
212 first_counter++;
213
214 if (first_counter >= NUM_INTERVALS) { /* Take n sets of readings for each shares value */
215 first_counter = 0;
216 second_counter++;
217 if (second_counter >= NUM_SETS)
218 exit(0); /* This task is done with its job */
219
220 /* Change share values depending on the test_num */
221 if (test_num == 1) {
222 /* Keep same ratio but change values */
223 myshares = MULTIPLIER * myshares;
224 } else {
225 /* Increase for odd task and decrease for even task */
226 if (my_group_num % 2)
227 myshares +=
228 baseshares * GRANULARITY / 100;
229 else
230 myshares -=
231 baseshares * GRANULARITY / 100;
232 }
233 write_to_file(mysharesfile, "w", myshares);
234 if (test_num == 3) {
235 /*
236 * Read the shares file and again calculate the cpu fraction
237 * No need to read tasks file as we do not migrate tasks
238 * No need to scan all shares file as total shares are const
239 */
240 if ((fmyshares =
241 read_shares_file(mysharesfile)) < 2)
242 tst_brkm(TBROK, cleanup,
243 "in reading shares files %s ",
244 mysharesfile);
245 exp_cpu_time =
246 (double)(fmyshares * 100) / (total_shares *
247 num_tasks);
248 }
249
250 fprintf(stdout, "\ntask-%d SHARES=%lu\n", my_group_num,
251 myshares);
252 } /* end if */
253 } /* end while */
254 } /* end main */
255