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