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_test04.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: 2                                                             */
31 /*                                                                            */
32 /* Test 09:     Heavy stress test with nice value change                      */
33 /* Test 10:     Heavy stress test (effect of heavy group on light group)      */
34 /*                                                                            */
35 /* Test Name:   cpu_controller_test04                                         */
36 /*                                                                            */
37 /* Test Assertion                                                             */
38 /*              Please refer to the file cpuctl_testplan.txt                  */
39 /*                                                                            */
40 /* Author:      Sudhir Kumar skumar@linux.vnet.ibm.com                        */
41 /*                                                                            */
42 /* History:                                                                   */
43 /* Created-     20/12/2007 -Sudhir Kumar <skumar@linux.vnet.ibm.com>          */
44 /*                                                                            */
45 /******************************************************************************/
46 
47 #include <unistd.h>
48 #include <math.h>
49 #include <signal.h>
50 #include <stdio.h>
51 #include <stdlib.h>
52 #include <string.h>
53 #include <sys/resource.h>
54 #include <sys/syscall.h>
55 #include <sys/time.h>
56 #include <sys/types.h>
57 #include <sys/stat.h>
58 #include <fcntl.h>
59 #include <time.h>
60 #include <unistd.h>
61 
62 #include "../libcontrollers/libcontrollers.h"
63 #include "test.h"		/* LTP harness APIs */
64 
65 #define TIME_INTERVAL	100	/* Time interval in seconds */
66 #define NUM_INTERVALS	2	/* How many iterations of TIME_INTERVAL */
67 
68 char *TCID = "cpuctl_test04";
69 int TST_TOTAL = 2;
70 pid_t scriptpid;
71 char path[] = "/dev/cpuctl";
72 
cleanup()73 extern void cleanup()
74 {
75 	kill(scriptpid, SIGUSR1);	/* Inform the shell to do cleanup */
76 	tst_exit();		/* Report exit status */
77 }
78 
79 volatile int timer_expired = 0;
80 
main(int argc,char * argv[])81 int main(int argc, char *argv[])
82 {
83 
84 	int test_num;
85 	int task_num;
86 	int len;
87 	int num_cpus;		/* Total time = TIME_INTERVAL *num_cpus in the machine */
88 	char mygroup[FILENAME_MAX], mytaskfile[FILENAME_MAX];
89 	char mysharesfile[FILENAME_MAX], ch;
90 	/* Following variables are to capture parameters from script */
91 	char *group_num_p, *mygroup_p, *script_pid_p, *num_cpus_p, *test_num_p,
92 	    *task_num_p;
93 	gid_t mygroup_num;	/* A number attached with a group */
94 	int fd;			/* A descriptor to open a fifo for synchronized start */
95 	int counter = 0;	/* To take n number of readings */
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 	unsigned long int mygroup_shares;
102 	time_t current_time, prev_time, delta_time;
103 	unsigned int fmyshares, num_tasks;	/* f-> from file. num_tasks is tasks in this group */
104 	struct sigaction newaction, oldaction;
105 
106 	mygroup_num = -1;
107 	num_cpus = 0;
108 	task_num = 0;
109 	test_num = 0;
110 
111 	/* Signal handling for alarm */
112 	sigemptyset(&newaction.sa_mask);
113 	newaction.sa_handler = signal_handler_alarm;
114 	newaction.sa_flags = 0;
115 	sigaction(SIGALRM, &newaction, &oldaction);
116 
117 	/* Collect the parameters passed by the script */
118 	group_num_p = getenv("GROUP_NUM");
119 	mygroup_p = getenv("MYGROUP");
120 	script_pid_p = getenv("SCRIPT_PID");
121 	num_cpus_p = getenv("NUM_CPUS");
122 	test_num_p = getenv("TEST_NUM");
123 	task_num_p = getenv("TASK_NUM");
124 	/* Check if all of them are valid */
125 	if ((test_num_p != NULL)
126 	    && (((test_num = atoi(test_num_p)) <= 10)
127 		&& ((test_num = atoi(test_num_p)) >= 9))) {
128 		if ((group_num_p != NULL) && (mygroup_p != NULL)
129 		    && (script_pid_p != NULL) && (num_cpus_p != NULL)
130 		    && (task_num_p != NULL)) {
131 			mygroup_num = atoi(group_num_p);
132 			scriptpid = atoi(script_pid_p);
133 			num_cpus = atoi(num_cpus_p);
134 			task_num = atoi(task_num_p);
135 			sprintf(mygroup, "%s", mygroup_p);
136 		} else {
137 			tst_brkm(TBROK, cleanup,
138 				 "Invalid other input parameters\n");
139 		}
140 	} else {
141 		tst_brkm(TBROK, cleanup, "Invalid test number passed\n");
142 	}
143 
144 	/*
145 	 * Let us give the default group 100 shares, as other groups will have
146 	 * a multiple of 100 shares.
147 	 * WARN: For large num of groups this may hit MAX_SHARES
148 	 */
149 	mygroup_shares = mygroup_num * 100;
150 
151 	sprintf(mytaskfile, "%s", mygroup);
152 	strcat(mytaskfile, "/tasks");
153 	sprintf(mysharesfile, "%s", mygroup);
154 	strcat(mysharesfile, "/cpu.shares");
155 	/* Need some technique so as only 1 task per grp writes to shares file */
156 	if (test_num == 9)
157 		write_to_file(mysharesfile, "w", mygroup_shares);	/* Write the shares of the group */
158 
159 	write_to_file(mytaskfile, "a", getpid());	/* Assign the task to it's group */
160 
161 	fd = open("./myfifo", 0);
162 	if (fd == -1) {
163 		tst_brkm(TBROK, cleanup,
164 			 "Could not open fifo for synchronization");
165 	}
166 
167 	read(fd, &ch, 1);	/* To block all tasks here and fire them up at the same time */
168 
169 	/*
170 	 * We now calculate the expected % cpu time of this task by getting
171 	 * it's group's shares, the total shares of all the groups and the
172 	 * number of tasks in this group.
173 	 */
174 	FLAG = 0;
175 	total_shares = 0;
176 	shares_pointer = &total_shares;
177 	len = strlen(path);
178 	if (!strncpy(fullpath, path, len))
179 		tst_brkm(TBROK, cleanup, "Could not copy directory path %s ",
180 			 path);
181 
182 	if (scan_shares_files(shares_pointer) != 0)
183 		tst_brkm(TBROK, cleanup,
184 			 "From function scan_shares_files in %s ", fullpath);
185 
186 	/* return val: -1 in case of function error, else 2 is min share value */
187 	if ((fmyshares = read_shares_file(mysharesfile)) < 2)
188 		tst_brkm(TBROK, cleanup, "in reading shares files  %s ",
189 			 mysharesfile);
190 
191 	if ((read_file(mytaskfile, GET_TASKS, &num_tasks)) < 0)
192 		tst_brkm(TBROK, cleanup, "in reading tasks files  %s ",
193 			 mytaskfile);
194 
195 	exp_cpu_time = (double)(fmyshares * 100) / (total_shares * num_tasks);
196 
197 	prev_time = time(NULL);	/* Note down the time */
198 
199 	while (1) {
200 		/* Need to run some cpu intensive task, which also frequently checks the timer value */
201 		double f = 274.345, mytime;	/*just a float number to take sqrt */
202 		alarm(TIME_INTERVAL);
203 		timer_expired = 0;
204 		while (!timer_expired)	/* Let the task run on cpu for TIME_INTERVAL */
205 			f = sqrt(f * f);	/* Time of this operation should not be high otherwise we can
206 						 * exceed the TIME_INTERVAL to measure cpu usage
207 						 */
208 		current_time = time(NULL);
209 		delta_time = current_time - prev_time;	/* Duration in case its not exact TIME_INTERVAL */
210 
211 		getrusage(0, &cpu_usage);
212 		total_cpu_time = (cpu_usage.ru_utime.tv_sec + cpu_usage.ru_utime.tv_usec * 1e-6 +	/* user time */
213 				  cpu_usage.ru_stime.tv_sec + cpu_usage.ru_stime.tv_usec * 1e-6);	/* system time */
214 		delta_cpu_time = total_cpu_time - prev_cpu_time;
215 
216 		prev_cpu_time = total_cpu_time;
217 		prev_time = current_time;
218 
219 		/* calculate % cpu time each task gets */
220 		if (delta_time > TIME_INTERVAL)
221 			mytime =
222 			    (delta_cpu_time * 100) / (delta_time * num_cpus);
223 		else
224 			mytime =
225 			    (delta_cpu_time * 100) / (TIME_INTERVAL * num_cpus);
226 
227 		fprintf(stdout, "Grp:-%3d task-%3d:CPU TIME{calc:-%6.2f(s)i.e. %6.2f(%%) exp:-%6.2f(%%)}\
228 with %3u shares in %lu (s) INTERVAL\n", mygroup_num, task_num, delta_cpu_time,
229 			mytime, exp_cpu_time, fmyshares, delta_time);
230 
231 		counter++;
232 
233 		if (counter >= NUM_INTERVALS) {	/* Take n sets of readings for each shares value */
234 			switch (test_num) {
235 			case 9:	/* Test 09 */
236 				exit(0);	/* This task is done with its job */
237 				break;
238 			case 10:	/* Test 10 */
239 				exit(0);	/* This task is done with its job */
240 				break;
241 			default:
242 				tst_brkm(TBROK, cleanup,
243 					 "Invalid test number passed\n");
244 				break;
245 
246 			}	/* end switch */
247 		}		/* end if */
248 	}			/* end while */
249 }				/* end main */
250