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#include "safe_macros.h"
61
62#ifdef DEBUG
63#define dbg(x...)	printf(x);
64#else
65#define dbg(x...)	do {}	while (0)
66#endif
67
68#define TIME_INTERVAL	30	/* Time interval in seconds */
69#define NUM_INTERVALS	3	/* How many iterations of TIME_INTERVAL */
70#define NUM_SETS	4	/* How many share values (with same ratio) */
71#define MULTIPLIER   	10	/* Rate at which share value gets multiplied */
72
73char *TCID = "cpu_controller_tests";
74int TST_TOTAL = 1;
75pid_t scriptpid;
76char path[FILENAME_MAX] = "/dev/cpuctl";
77
78extern void cleanup(void)
79{
80	kill(scriptpid, SIGUSR1);	/* Inform the shell to do cleanup */
81	/* Report exit status */
82}
83
84int main(int argc, char *argv[])
85{
86
87	int num_cpus, test_num, len;	/* Total time = TIME_INTERVAL*num_cpus */
88	char mygroup[FILENAME_MAX], mytaskfile[FILENAME_MAX];
89	char mysharesfile[FILENAME_MAX], ch;
90	pid_t pid;
91	int my_group_num;	/* A number attached with a group */
92	int fd;			/* To open a fifo for synchronization */
93	int first_counter = 0;	/* To take n number of readings */
94	int second_counter = 0;	/* no of times shares have changed */
95	double total_cpu_time;	/* Accumulated cpu time */
96	double delta_cpu_time;	/* Time the task could run on cpu(s) */
97	double prev_cpu_time = 0;
98	double exp_cpu_time;	/* Exp time in % by shares calculation */
99	struct rusage cpu_usage;
100	time_t current_time, prev_time, delta_time;
101	unsigned long int myshares = 2, baseshares = 1000;
102	unsigned int fmyshares, num_tasks;
103	struct sigaction newaction, oldaction;
104
105	num_cpus = 0;
106	test_num = 0;
107	my_group_num = -1;
108
109	/* Signal handling for alarm */
110	sigemptyset(&newaction.sa_mask);
111	newaction.sa_handler = signal_handler_alarm;
112	newaction.sa_flags = 0;
113	sigaction(SIGALRM, &newaction, &oldaction);
114
115	/* Check if all parameters passed are correct */
116	if ((argc < 5) || ((my_group_num = atoi(argv[1])) <= 0) ||
117	    ((scriptpid = atoi(argv[3])) <= 0) ||
118	    ((num_cpus = atoi(argv[4])) <= 0) ||
119	    (test_num = atoi(argv[5])) <= 0)
120		tst_brkm(TBROK, cleanup, "Invalid input parameters");
121
122	if (test_num == 1)
123		myshares *= my_group_num;
124	else if (test_num == 3)
125		myshares = baseshares;
126	else
127		tst_brkm(TBROK, cleanup, "Wrong Test num passed. Exiting.");
128
129	sprintf(mygroup, "%s", argv[2]);
130	sprintf(mytaskfile, "%s", mygroup);
131	sprintf(mysharesfile, "%s", mygroup);
132	strcat(mytaskfile, "/tasks");
133	strcat(mysharesfile, "/cpu.shares");
134	pid = getpid();
135	write_to_file(mytaskfile, "a", pid);	/* Assign task to it's group */
136	write_to_file(mysharesfile, "w", myshares);
137	dbg("Default task's initial shares = %u", myshares);
138
139	fd = SAFE_OPEN(cleanup, "./myfifo", 0);
140
141	read(fd, &ch, 1);	/* To fire all the tasks up at the same time */
142
143	/*
144	 * We need not calculate the expected % cpu time of this task, as
145	 * neither it is required nor it can be predicted as there are idle
146	 * system tasks (and others too) in this group.
147	 */
148	FLAG = 0;
149	total_shares = 0;
150	shares_pointer = &total_shares;
151	len = strlen(path);
152	if (!strncpy(fullpath, path, len))
153		tst_brkm(TBROK, cleanup,
154			 "Could not copy directory path %s ", path);
155
156	if (scan_shares_files(shares_pointer) != 0)
157		tst_brkm(TBROK, cleanup,
158			 "From function scan_shares_files in %s ", fullpath);
159
160	/* return val -1 in case of function error, else 2 is min share value */
161	if ((fmyshares = read_shares_file(mysharesfile)) < 2)
162		tst_brkm(TBROK, cleanup,
163			 "in reading shares files  %s ", mysharesfile);
164
165	if ((read_file(mytaskfile, GET_TASKS, &num_tasks)) < 0)
166		tst_brkm(TBROK, cleanup,
167			 "in reading tasks files  %s ", mytaskfile);
168
169	exp_cpu_time = (double)(fmyshares * 100) / (total_shares * num_tasks);
170
171	prev_time = time(NULL);	/* Note down the time */
172
173	while (1) {
174		/*
175		 * Need to run some cpu intensive task, which also
176		 * frequently checks the timer value
177		 */
178		double f = 274.345, mytime;	/*just a float number for sqrt */
179		alarm(TIME_INTERVAL);
180		timer_expired = 0;
181		/*
182		 * Let the task run on cpu for TIME_INTERVAL. Time of this
183		 * operation should not be high otherwise we can exceed the
184		 * TIME_INTERVAL to measure cpu usage
185		 */
186		while (!timer_expired)
187			f = sqrt(f * f);
188
189		current_time = time(NULL);
190		/* Duration in case its not exact TIME_INTERVAL */
191		delta_time = current_time - prev_time;
192
193		getrusage(0, &cpu_usage);
194		/* total_cpu_time = total user time + total sys time */
195		total_cpu_time = (cpu_usage.ru_utime.tv_sec +
196				  cpu_usage.ru_utime.tv_usec * 1e-6 +
197				  cpu_usage.ru_stime.tv_sec +
198				  cpu_usage.ru_stime.tv_usec * 1e-6);
199		delta_cpu_time = total_cpu_time - prev_cpu_time;
200
201		prev_cpu_time = total_cpu_time;
202		prev_time = current_time;
203
204		/* calculate % cpu time each task gets */
205		if (delta_time > TIME_INTERVAL)
206			mytime = (delta_cpu_time * 100) /
207			    (delta_time * num_cpus);
208		else
209			mytime = (delta_cpu_time * 100) /
210			    (TIME_INTERVAL * num_cpus);
211
212		/*
213		 * Lets print the results. The exp cpu time calculated may not
214		 * be correct due to running system tasks at the moment
215		 */
216		fprintf(stdout, "DEF TASK:CPU TIME{calc:-%6.2f(s)"
217			" i.e. %6.2f(%%) exp:-%6.2f(%%)} with %lu(shares)"
218			" in %lu (s) INTERVAL\n", delta_cpu_time, mytime,
219			exp_cpu_time, myshares, delta_time);
220		first_counter++;
221
222		/* Take n sets of readings for each shares value */
223		if (first_counter >= NUM_INTERVALS) {
224			first_counter = 0;
225			second_counter++;
226			if (second_counter >= NUM_SETS)
227				exit(0);	/* This task is done */
228
229			/* Keep same ratio but change values */
230			if (test_num == 1) {
231				myshares = MULTIPLIER * myshares;
232				write_to_file(mysharesfile, "w", myshares);
233			}
234			/* No need to change shares for def task for test 3 */
235
236		}		/* end if */
237	}			/* end while */
238}				/* end main */
239