cpuctl_def_task01.c revision b6ff02cd9592e40c4b435ff7755cb69572a23f47 
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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA    */
18/*                                                                            */
19/******************************************************************************/
20
21/******************************************************************************/
22/*                                                                            */
23/* File:        cpuctl_task_def01.c                                           */
24/*                                                                            */
25/* Description: This is a c program that runs as a default task in a default  */
26/*              group to create an ideal scenario. In this default group all  */
27/*              the system tasks will be running along with this spinning task*/
28/*              The file is to be used by tests 1-3.                          */
29/*                                                                            */
30/* Total Tests: 1                                                             */
31/*                                                                            */
32/* Test Name:   cpu_controller_tests                                          */
33/*                                                                            */
34/* Test Assertion                                                             */
35/*              Please refer to the file cpuctl_testplan.txt                  */
36/*                                                                            */
37/* Author:      Sudhir Kumar skumar@linux.vnet.ibm.com                        */
38/*                                                                            */
39/* History:                                                                   */
40/* Created-     14/11/2008 -Sudhir Kumar <skumar@linux.vnet.ibm.com>          */
41/*                                                                            */
42/******************************************************************************/
43
44/* Standard Include Files */
45#include <unistd.h>
46#include <math.h>
47#include <signal.h>
48#include <stdio.h>
49#include <stdlib.h>
50#include <string.h>
51#include <sys/resource.h>
52#include <sys/syscall.h>
53#include <sys/time.h>
54#include <sys/types.h>
55#include <sys/stat.h>
56#include <fcntl.h>
57#include <time.h>
58#include <unistd.h>
59
60#include "../libcontrollers/libcontrollers.h"
61#include "test.h"		/* LTP harness APIs*/
62
63#ifdef DEBUG
64#define dbg(x...)	printf(x);
65#else
66#define dbg(x...)	do {}	while (0)
67#endif
68
69#define TIME_INTERVAL	30	/* Time interval in seconds*/
70#define NUM_INTERVALS	3       /* How many iterations of TIME_INTERVAL */
71#define NUM_SETS	4	/* How many share values (with same ratio)*/
72#define MULTIPLIER   	10      /* Rate at which share value gets multiplied*/
73
74char *TCID = "cpu_controller_tests";
75int TST_TOTAL = 1;
76pid_t scriptpid;
77char path[FILENAME_MAX] = "/dev/cpuctl";
78
79extern void cleanup()
80{
81	kill(scriptpid, SIGUSR1);/* Inform the shell to do cleanup*/
82		/* Report exit status*/
83}
84volatile int timer_expired = 0;
85
86int main(int argc, char *argv[])
87{
88
89	int num_cpus, test_num, len;	/* Total time = TIME_INTERVAL*num_cpus*/
90	char mygroup[FILENAME_MAX], mytaskfile[FILENAME_MAX];
91	char mysharesfile[FILENAME_MAX], ch;
92	pid_t pid;
93	int my_group_num;	        /* A number attached with a group*/
94	int fd;          	        /* To open a fifo for synchronization*/
95	int first_counter = 0;  	/* To take n number of readings*/
96	int second_counter = 0;    	/* no of times shares have changed*/
97	double total_cpu_time;  	/* Accumulated cpu time*/
98	double delta_cpu_time;  	/* Time the task could run on cpu(s)*/
99	double prev_cpu_time = 0;
100	double exp_cpu_time;		/* Exp time in % by shares calculation*/
101	struct rusage cpu_usage;
102	time_t current_time, prev_time, delta_time;
103	unsigned long int myshares = 2, baseshares = 1000;
104	unsigned int fmyshares, num_tasks;
105	struct sigaction newaction, oldaction;
106
107	num_cpus = 0;
108	test_num = 0;
109	my_group_num = -1;
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	/* Check if all parameters passed are correct*/
118	if ((argc < 5) || ((my_group_num = atoi(argv[1])) <= 0) || \
119				((scriptpid = atoi(argv[3])) <= 0) || \
120					((num_cpus = atoi(argv[4])) <= 0) || \
121						(test_num = atoi(argv[5])) <= 0)
122		tst_brkm(TBROK, cleanup, "Invalid input parameters\n");
123
124	if (test_num == 1)
125		myshares *= my_group_num;
126	else if (test_num == 3)
127		myshares = baseshares;
128	else
129		tst_brkm(TBROK, cleanup, "Wrong Test num passed. Exiting.\n");
130
131	sprintf(mygroup, "%s", argv[2]);
132	sprintf(mytaskfile, "%s", mygroup);
133	sprintf(mysharesfile, "%s", mygroup);
134	strcat(mytaskfile, "/tasks");
135	strcat(mysharesfile, "/cpu.shares");
136	pid = getpid();
137	write_to_file(mytaskfile, "a", pid);    /* Assign task to it's group*/
138	write_to_file(mysharesfile, "w", myshares);
139	dbg("Default task's initial shares = %u", myshares);
140
141	fd = open("./myfifo", 0);
142	if (fd == -1)
143		tst_brkm(TBROK, cleanup, "Could not open fifo to synchronizae");
144
145	read(fd, &ch, 1);	/* To fire all the tasks up at the same time*/
146
147	/*
148	 * We need not calculate the expected % cpu time of this task, as
149	 * neither it is required nor it can be predicted as there are idle
150	 * system tasks (and others too) in this group.
151	 */
152	FLAG = 0;
153	total_shares = 0;
154	shares_pointer = &total_shares;
155	len = strlen(path);
156	if (!strncpy(fullpath, path, len))
157		tst_brkm(TBROK, cleanup,
158			 "Could not copy directory path %s ", path);
159
160	if (scan_shares_files(shares_pointer) != 0)
161		tst_brkm(TBROK, cleanup,
162		 "From function scan_shares_files in %s ", fullpath);
163
164	/* return val -1 in case of function error, else 2 is min share value */
165	if ((fmyshares = read_shares_file(mysharesfile)) < 2)
166		tst_brkm(TBROK, cleanup,
167			 "in reading shares files  %s ", mysharesfile);
168
169	if ((read_file(mytaskfile, GET_TASKS, &num_tasks)) < 0)
170		tst_brkm(TBROK, cleanup,
171			 "in reading tasks files  %s ", mytaskfile);
172
173	exp_cpu_time = (double)(fmyshares * 100) / (total_shares * num_tasks);
174
175	prev_time = time(NULL);	 /* Note down the time*/
176
177	while (1) {
178		/*
179		 * Need to run some cpu intensive task, which also
180		 * frequently checks the timer value
181		 */
182		double f = 274.345, mytime;	/*just a float number for sqrt*/
183		alarm(TIME_INTERVAL);
184		timer_expired = 0;
185		/*
186		 * Let the task run on cpu for TIME_INTERVAL. Time of this
187		 * operation should not be high otherwise we can exceed the
188		 * TIME_INTERVAL to measure cpu usage
189		 */
190		while (!timer_expired)
191			f = sqrt(f * f);
192
193		current_time = time(NULL);
194		/* Duration in case its not exact TIME_INTERVAL*/
195		delta_time = current_time - prev_time;
196
197		getrusage(0, &cpu_usage);
198		/* total_cpu_time = total user time + total sys time */
199		total_cpu_time = (cpu_usage.ru_utime.tv_sec +
200				cpu_usage.ru_utime.tv_usec * 1e-6 +
201				cpu_usage.ru_stime.tv_sec +
202				cpu_usage.ru_stime.tv_usec * 1e-6) ;
203		delta_cpu_time = total_cpu_time - prev_cpu_time;
204
205		prev_cpu_time = total_cpu_time;
206		prev_time = current_time;
207
208		/* calculate % cpu time each task gets */
209		if (delta_time > TIME_INTERVAL)
210			mytime = (delta_cpu_time * 100) /
211					 (delta_time * num_cpus);
212		else
213			mytime = (delta_cpu_time * 100) /
214					 (TIME_INTERVAL * num_cpus);
215
216		/*
217		 * Lets print the results. The exp cpu time calculated may not
218		 * be correct due to running system tasks at the moment
219		 */
220		fprintf(stdout, "DEF TASK:CPU TIME{calc:-%6.2f(s)"
221			" i.e. %6.2f(%%) exp:-%6.2f(%%)} with %lu(shares)"
222			" in %lu (s) INTERVAL\n", delta_cpu_time,  mytime,
223					 exp_cpu_time, myshares, delta_time);
224		first_counter++;
225
226		/* Take n sets of readings for each shares value*/
227		if (first_counter >= NUM_INTERVALS) {
228			first_counter = 0;
229			second_counter++;
230			if (second_counter >= NUM_SETS)
231				exit(0);	/* This task is done */
232
233			/* Keep same ratio but change values*/
234			if (test_num == 1) {
235				myshares = MULTIPLIER * myshares;
236				write_to_file(mysharesfile, "w", myshares);
237			}
238			/* No need to change shares for def task for test 3 */
239
240		}/* end if*/
241	}/* end while*/
242}/* end main*/
243