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_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#include <unistd.h>
45#include <math.h>
46#include <signal.h>
47#include <stdio.h>
48#include <stdlib.h>
49#include <string.h>
50#include <sys/resource.h>
51#include <sys/syscall.h>
52#include <sys/time.h>
53#include <sys/types.h>
54#include <sys/stat.h>
55#include <fcntl.h>
56#include <time.h>
57
58#include "../libcontrollers/libcontrollers.h"
59#include "test.h"		/* LTP harness APIs */
60
61#ifdef DEBUG
62#define dbg(x...)	printf(x);
63#else
64#define dbg(x...)	do {}	while (0)
65#endif
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	/* Rate at which share value gets multiplied */
71
72char *TCID = "cpu_controller_tests";
73int TST_TOTAL = 1;
74pid_t scriptpid;
75char path[FILENAME_MAX] = "/dev/cpuctl";
76
77extern void cleanup(void)
78{
79	kill(scriptpid, SIGUSR1);	/* Inform the shell to do cleanup */
80	/* Report exit status */
81}
82
83volatile int timer_expired = 0;
84
85int main(int argc, char *argv[])
86{
87
88	int num_cpus, test_num, len;	/* Total time = TIME_INTERVAL*num_cpus */
89	char mygroup[FILENAME_MAX], mytaskfile[FILENAME_MAX];
90	char mysharesfile[FILENAME_MAX], ch;
91	pid_t pid;
92	int my_group_num;	/* A number attached with a group */
93	int fd;			/* To open a fifo for synchronization */
94	int first_counter = 0;	/* To take n number of readings */
95	int second_counter = 0;	/* no of times shares have changed */
96	double total_cpu_time;	/* Accumulated cpu time */
97	double delta_cpu_time;	/* Time the task could run on cpu(s) */
98	double prev_cpu_time = 0;
99	double exp_cpu_time;	/* Exp time in % 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;
103	unsigned int fmyshares, num_tasks;
104	struct sigaction newaction, oldaction;
105
106	num_cpus = 0;
107	test_num = 0;
108	my_group_num = -1;
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	if (test_num == 1)
124		myshares *= my_group_num;
125	else if (test_num == 3)
126		myshares = baseshares;
127	else
128		tst_brkm(TBROK, cleanup, "Wrong Test num passed. Exiting.\n");
129
130	sprintf(mygroup, "%s", argv[2]);
131	sprintf(mytaskfile, "%s", mygroup);
132	sprintf(mysharesfile, "%s", mygroup);
133	strcat(mytaskfile, "/tasks");
134	strcat(mysharesfile, "/cpu.shares");
135	pid = getpid();
136	write_to_file(mytaskfile, "a", pid);	/* Assign task to it's group */
137	write_to_file(mysharesfile, "w", myshares);
138	dbg("Default task's initial shares = %u", myshares);
139
140	fd = open("./myfifo", 0);
141	if (fd == -1)
142		tst_brkm(TBROK, cleanup, "Could not open fifo to synchronizae");
143
144	read(fd, &ch, 1);	/* To fire all the tasks up at the same time */
145
146	/*
147	 * We need not calculate the expected % cpu time of this task, as
148	 * neither it is required nor it can be predicted as there are idle
149	 * system tasks (and others too) 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,
157			 "Could not copy directory path %s ", 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,
166			 "in reading shares files  %s ", mysharesfile);
167
168	if ((read_file(mytaskfile, GET_TASKS, &num_tasks)) < 0)
169		tst_brkm(TBROK, cleanup,
170			 "in reading tasks files  %s ", 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		/*
178		 * Need to run some cpu intensive task, which also
179		 * frequently checks the timer value
180		 */
181		double f = 274.345, mytime;	/*just a float number for sqrt */
182		alarm(TIME_INTERVAL);
183		timer_expired = 0;
184		/*
185		 * Let the task run on cpu for TIME_INTERVAL. Time of this
186		 * operation should not be high otherwise we can exceed the
187		 * TIME_INTERVAL to measure cpu usage
188		 */
189		while (!timer_expired)
190			f = sqrt(f * f);
191
192		current_time = time(NULL);
193		/* Duration in case its not exact TIME_INTERVAL */
194		delta_time = current_time - prev_time;
195
196		getrusage(0, &cpu_usage);
197		/* total_cpu_time = total user time + total sys time */
198		total_cpu_time = (cpu_usage.ru_utime.tv_sec +
199				  cpu_usage.ru_utime.tv_usec * 1e-6 +
200				  cpu_usage.ru_stime.tv_sec +
201				  cpu_usage.ru_stime.tv_usec * 1e-6);
202		delta_cpu_time = total_cpu_time - prev_cpu_time;
203
204		prev_cpu_time = total_cpu_time;
205		prev_time = current_time;
206
207		/* calculate % cpu time each task gets */
208		if (delta_time > TIME_INTERVAL)
209			mytime = (delta_cpu_time * 100) /
210			    (delta_time * num_cpus);
211		else
212			mytime = (delta_cpu_time * 100) /
213			    (TIME_INTERVAL * num_cpus);
214
215		/*
216		 * Lets print the results. The exp cpu time calculated may not
217		 * be correct due to running system tasks at the moment
218		 */
219		fprintf(stdout, "DEF TASK:CPU TIME{calc:-%6.2f(s)"
220			" i.e. %6.2f(%%) exp:-%6.2f(%%)} with %lu(shares)"
221			" in %lu (s) INTERVAL\n", delta_cpu_time, mytime,
222			exp_cpu_time, myshares, delta_time);
223		first_counter++;
224
225		/* Take n sets of readings for each shares value */
226		if (first_counter >= NUM_INTERVALS) {
227			first_counter = 0;
228			second_counter++;
229			if (second_counter >= NUM_SETS)
230				exit(0);	/* This task is done */
231
232			/* Keep same ratio but change values */
233			if (test_num == 1) {
234				myshares = MULTIPLIER * myshares;
235				write_to_file(mysharesfile, "w", myshares);
236			}
237			/* No need to change shares for def task for test 3 */
238
239		}		/* end if */
240	}			/* end while */
241}				/* end main */
242