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 #include "safe_macros.h"
66
67 #define TIME_INTERVAL 30 /* Time interval in seconds */
68 #define NUM_INTERVALS 3 /* How many iterations of TIME_INTERVAL */
69 #define NUM_SETS 4 /* How many share values (with same ratio) */
70 #define MULTIPLIER 10 /* decides the rate at which share value gets multiplied */
71 #define GRANULARITY 5 /* % value by which shares of a group changes */
72 char *TCID = "cpuctl_test01";
73 int TST_TOTAL = 1;
74 pid_t scriptpid;
75 char path[] = "/dev/cpuctl";
cleanup(void)76 extern void cleanup(void)
77 {
78 kill(scriptpid, SIGUSR1); /* Inform the shell to do cleanup */
79 tst_exit(); /* Report exit status */
80 }
81
main(int argc,char * argv[])82 int main(int argc, char *argv[])
83 {
84
85 int num_cpus;
86 int test_num;
87 int len; /* Total time = TIME_INTERVAL *num_cpus in the machine */
88 char mygroup[FILENAME_MAX], mytaskfile[FILENAME_MAX];
89 char mysharesfile[FILENAME_MAX], ch;
90 pid_t pid;
91 gid_t my_group_num; /* A number attached with a group */
92 int fd; /* A descriptor to open a fifo for synchronized start */
93 int first_counter = 0; /* To take n number of readings */
94 int second_counter = 0; /* To track number of times the base value of shares has been changed */
95 double total_cpu_time, /* Accumulated cpu time */
96 delta_cpu_time, /* Time the task could run on cpu(s) (in an interval) */
97 prev_cpu_time = 0;
98 double exp_cpu_time; /* Expected time in % as obtained by shares calculation */
99 struct rusage cpu_usage;
100 time_t current_time, prev_time, delta_time;
101 unsigned long int myshares = 2, baseshares = 1000; /* Simply the base value to start with */
102 unsigned int fmyshares, num_tasks; /* f-> from file. num_tasks is tasks in this group */
103 struct sigaction newaction, oldaction;
104
105 my_group_num = -1;
106 num_cpus = 0;
107 test_num = 0;
108
109 /* Signal handling for alarm */
110 sigemptyset(&newaction.sa_mask);
111 newaction.sa_handler = signal_handler_alarm;
112 newaction.sa_flags = 0;
113 sigaction(SIGALRM, &newaction, &oldaction);
114
115 /* Check if all parameters passed are correct */
116 if ((argc < 5) || ((my_group_num = atoi(argv[1])) <= 0)
117 || ((scriptpid = atoi(argv[3])) <= 0)
118 || ((num_cpus = atoi(argv[4])) <= 0)
119 || (test_num = atoi(argv[5])) <= 0) {
120 tst_brkm(TBROK, cleanup, "Invalid input parameters");
121 }
122
123 if (test_num == 1) /* Test 01 & Test 02 */
124 myshares *= my_group_num;
125 else if (test_num == 3) /* Test 03 */
126 myshares = baseshares;
127 else {
128 tst_brkm(TBROK, cleanup,
129 "Wrong Test number passed. Exiting Test...");
130 }
131
132 sprintf(mygroup, "%s", argv[2]);
133 sprintf(mytaskfile, "%s", mygroup);
134 sprintf(mysharesfile, "%s", mygroup);
135 strcat(mytaskfile, "/tasks");
136 strcat(mysharesfile, "/cpu.shares");
137 pid = getpid();
138 write_to_file(mytaskfile, "a", pid); /* Assign the task to it's group */
139 write_to_file(mysharesfile, "w", myshares);
140
141 fd = SAFE_OPEN(cleanup, "./myfifo", 0);
142
143 fprintf(stdout, "\ntask-%d SHARES=%lu\n", my_group_num, myshares);
144 read(fd, &ch, 1); /* To block all tasks here and fire them up at the same time */
145
146 /*
147 * We now calculate the expected % cpu time of this task by getting
148 * it's group's shares, the total shares of all the groups and the
149 * number of tasks in this group.
150 */
151 FLAG = 0;
152 total_shares = 0;
153 shares_pointer = &total_shares;
154 len = strlen(path);
155 if (!strncpy(fullpath, path, len))
156 tst_brkm(TBROK, cleanup, "Could not copy directory path %s ",
157 path);
158
159 if (scan_shares_files(shares_pointer) != 0)
160 tst_brkm(TBROK, cleanup,
161 "From function scan_shares_files in %s ", fullpath);
162
163 /* return val: -1 in case of function error, else 2 is min share value */
164 if ((fmyshares = read_shares_file(mysharesfile)) < 2)
165 tst_brkm(TBROK, cleanup, "in reading shares files %s ",
166 mysharesfile);
167
168 if ((read_file(mytaskfile, GET_TASKS, &num_tasks)) < 0)
169 tst_brkm(TBROK, cleanup, "in reading tasks files %s ",
170 mytaskfile);
171
172 exp_cpu_time = (double)(fmyshares * 100) / (total_shares * num_tasks);
173
174 prev_time = time(NULL); /* Note down the time */
175
176 while (1) {
177 /* Need to run some cpu intensive task, which also frequently checks the timer value */
178 double f = 274.345, mytime; /*just a float number to take sqrt */
179 alarm(TIME_INTERVAL);
180 timer_expired = 0;
181 while (!timer_expired) /* Let the task run on cpu for TIME_INTERVAL */
182 f = sqrt(f * f); /* Time of this operation should not be high otherwise we can
183 * exceed the TIME_INTERVAL to measure cpu usage
184 */
185 current_time = time(NULL);
186 delta_time = current_time - prev_time; /* Duration in case its not exact TIME_INTERVAL */
187
188 getrusage(0, &cpu_usage);
189 total_cpu_time = (cpu_usage.ru_utime.tv_sec + cpu_usage.ru_utime.tv_usec * 1e-6 + /*user */
190 cpu_usage.ru_stime.tv_sec + cpu_usage.ru_stime.tv_usec * 1e-6); /*sys */
191 delta_cpu_time = total_cpu_time - prev_cpu_time;
192
193 prev_cpu_time = total_cpu_time;
194 prev_time = current_time;
195
196 /* calculate % cpu time each task gets */
197 if (delta_time > TIME_INTERVAL)
198 mytime =
199 (delta_cpu_time * 100) / (delta_time * num_cpus);
200 else
201 mytime =
202 (delta_cpu_time * 100) / (TIME_INTERVAL * num_cpus);
203
204 fprintf(stdout, "task-%d:CPU TIME{calc:-%6.2f(s)i.e. %6.2f(%%) exp:-%6.2f(%%)}\
205 with %lu(shares) in %lu (s) INTERVAL\n", my_group_num, delta_cpu_time, mytime,
206 exp_cpu_time, myshares, delta_time);
207 first_counter++;
208
209 if (first_counter >= NUM_INTERVALS) { /* Take n sets of readings for each shares value */
210 first_counter = 0;
211 second_counter++;
212 if (second_counter >= NUM_SETS)
213 exit(0); /* This task is done with its job */
214
215 /* Change share values depending on the test_num */
216 if (test_num == 1) {
217 /* Keep same ratio but change values */
218 myshares = MULTIPLIER * myshares;
219 } else {
220 /* Increase for odd task and decrease for even task */
221 if (my_group_num % 2)
222 myshares +=
223 baseshares * GRANULARITY / 100;
224 else
225 myshares -=
226 baseshares * GRANULARITY / 100;
227 }
228 write_to_file(mysharesfile, "w", myshares);
229 if (test_num == 3) {
230 /*
231 * Read the shares file and again calculate the cpu fraction
232 * No need to read tasks file as we do not migrate tasks
233 * No need to scan all shares file as total shares are const
234 */
235 if ((fmyshares =
236 read_shares_file(mysharesfile)) < 2)
237 tst_brkm(TBROK, cleanup,
238 "in reading shares files %s ",
239 mysharesfile);
240 exp_cpu_time =
241 (double)(fmyshares * 100) / (total_shares *
242 num_tasks);
243 }
244
245 fprintf(stdout, "\ntask-%d SHARES=%lu\n", my_group_num,
246 myshares);
247 } /* end if */
248 } /* end while */
249 } /* end main */
250