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 (at) linux.vnet.ibm.com */ 42 /* */ 43 /* History: */ 44 /* Created- 20/12/2007 -Sudhir Kumar <skumar (at) 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"; 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 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
