cpuctl_test01.c revision c50bfa605c087cfe73911d33187dc424e4b3a2f4 
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_test01.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: 3                                                             */
31/*                                                                            */
32/* Test 01:     Tests if fairness persists among different runs               */
33/* Test 02:     Tests fairness with respect to absolute share values          */
34/* Test 03:     Granularity test with respect to shares values                */
35/*                                                                            */
36/* Test Name:   cpu_controller_test01                                         */
37/*                                                                            */
38/* Test Assertion                                                             */
39/*              Please refer to the file cpuctl_testplan.txt                  */
40/*                                                                            */
41/* Author:      Sudhir Kumar skumar@linux.vnet.ibm.com                        */
42/*                                                                            */
43/* History:                                                                   */
44/* Created-     20/12/2007 -Sudhir Kumar <skumar@linux.vnet.ibm.com>          */
45/*                                                                            */
46/******************************************************************************/
47
48/* Standard Include Files */
49#include <unistd.h>
50#include <math.h>
51#include <signal.h>
52#include <stdio.h>
53#include <stdlib.h>
54#include <string.h>
55#include <sys/resource.h>
56#include <sys/syscall.h>
57#include <sys/time.h>
58#include <sys/types.h>
59#include <sys/stat.h>
60#include <fcntl.h>
61#include <time.h>
62#include <unistd.h>
63
64#include "../libcontrollers/libcontrollers.h"
65#include "test.h"		/* LTP harness APIs*/
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      /* decides the rate at which share value gets multiplied*/
71#define GRANULARITY    5       /* % value by which shares of a group changes */
72extern int Tst_count;
73char *TCID = "cpu_controller_test01";
74int TST_TOTAL = 1;
75pid_t scriptpid;
76char path[] = "/dev/cpuctl";
77extern void
78cleanup()
79{
80	kill (scriptpid, SIGUSR1);/* Inform the shell to do cleanup*/
81	tst_exit ();		/* Report exit status*/
82}
83int 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 in the machine */
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		fd,          	        /* A descriptor to open a fifo for synchronized start*/
94		first_counter =0,  	/* To take n number of readings*/
95		second_counter=0;      	/* To track number of times the base value of shares has been changed*/
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	time_t current_time, prev_time, delta_time;
102	unsigned long int myshares = 2, baseshares = 1000;	/* Simply the base value to start with*/
103	unsigned int fmyshares, num_tasks;/* f-> from file. num_tasks is tasks in this group*/
104	struct sigaction newaction, oldaction;
105
106	/* Signal handling for alarm*/
107	sigemptyset (&newaction.sa_mask);
108	newaction.sa_handler = signal_handler_alarm;
109	newaction.sa_flags=0;
110	sigaction (SIGALRM, &newaction, &oldaction);
111
112	/* Check if all parameters passed are correct*/
113	if ((argc < 5) || ((my_group_num = atoi(argv[1])) <= 0) || ((scriptpid = atoi(argv[3])) <= 0) || ((num_cpus = atoi(argv[4])) <= 0) || (test_num = atoi(argv[5])) <= 0)
114	{
115		tst_brkm (TBROK, cleanup, "Invalid input parameters\n");
116	}
117
118	if (test_num == 1)	/* Test 01 & Test 02 */
119		myshares *= my_group_num;
120	else if (test_num == 3) /* Test 03 */
121		myshares = baseshares;
122	else
123	{
124		tst_brkm (TBROK, cleanup, "Wrong Test number passed. Exiting Test...\n");
125	}
126
127	sprintf(mygroup,"%s", argv[2]);
128	sprintf(mytaskfile, "%s", mygroup);
129	sprintf(mysharesfile, "%s", mygroup);
130	strcat (mytaskfile,"/tasks");
131	strcat (mysharesfile,"/cpu.shares");
132	pid = getpid();
133	write_to_file (mytaskfile, "a", pid);    /* Assign the task to it's group*/
134	write_to_file (mysharesfile, "w", myshares);
135
136	fd = open ("./myfifo", 0);
137	if (fd == -1)
138	{
139		tst_brkm (TBROK, cleanup, "Could not open fifo for synchronization");
140	}
141
142	fprintf(stdout,"\ntask-%d SHARES=%lu\n",my_group_num, myshares);
143	read (fd, &ch, 1);	         /* To block all tasks here and fire them up at the same time*/
144
145	/*
146	 * We now calculate the expected % cpu time of this task by getting
147	 * it's group's shares, the total shares of all the groups and the
148	 * number of tasks in this group.
149	 */
150	FLAG = 0;
151	total_shares = 0;
152	shares_pointer = &total_shares;
153	len = strlen (path);
154	if (!strncpy (fullpath, path, len))
155		tst_brkm (TBROK, cleanup, "Could not copy directory path %s ", path);
156
157	if (scan_shares_files() != 0)
158		tst_brkm (TBROK, cleanup, "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, "in reading shares files  %s ", mysharesfile);
163
164	if ((read_file (mytaskfile, GET_TASKS, &num_tasks)) < 0)
165		tst_brkm (TBROK, cleanup, "in reading tasks files  %s ", mytaskfile);
166
167	exp_cpu_time = (double)(fmyshares * 100) /(total_shares * num_tasks);
168
169	prev_time = time (NULL);	 /* Note down the time*/
170
171	while (1)
172	{
173		/* Need to run some cpu intensive task, which also frequently checks the timer value*/
174		double f = 274.345, mytime;	/*just a float number to take sqrt*/
175		alarm (TIME_INTERVAL);
176		timer_expired = 0;
177		while (!timer_expired)	/* Let the task run on cpu for TIME_INTERVAL*/
178			f = sqrt (f*f); /* Time of this operation should not be high otherwise we can
179					 * exceed the TIME_INTERVAL to measure cpu usage
180					 */
181			current_time = time (NULL);
182			delta_time = current_time - prev_time;	/* Duration in case its not exact TIME_INTERVAL*/
183
184			getrusage (0, &cpu_usage);
185			total_cpu_time = (cpu_usage.ru_utime.tv_sec + cpu_usage.ru_utime.tv_usec * 1e-6 + /*user*/
186					cpu_usage.ru_stime.tv_sec + cpu_usage.ru_stime.tv_usec * 1e-6) ;  /*sys*/
187					delta_cpu_time = total_cpu_time - prev_cpu_time;
188
189			prev_cpu_time = total_cpu_time;
190			prev_time = current_time;
191
192			/* calculate % cpu time each task gets */
193			if (delta_time > TIME_INTERVAL)
194				mytime =  (delta_cpu_time * 100) / (delta_time * num_cpus);
195			else
196				mytime =  (delta_cpu_time * 100) / (TIME_INTERVAL * num_cpus);
197
198			fprintf (stdout,"task-%d:CPU TIME{calc:-%6.2f(s)i.e. %6.2f(%%) exp:-%6.2f(%%)}\
199with %lu(shares) in %lu (s) INTERVAL\n",my_group_num, delta_cpu_time, mytime,\
200exp_cpu_time, myshares, delta_time);
201			first_counter++;
202
203			if (first_counter >= NUM_INTERVALS)	/* Take n sets of readings for each shares value*/
204			{
205				first_counter = 0;
206				second_counter++;
207				if (second_counter >= NUM_SETS)
208					exit (0);		/* This task is done with its job*/
209
210                                /* Change share values depending on the test_num */
211                                if (test_num ==1)
212                                {
213                                        /* Keep same ratio but change values*/
214                                        myshares = MULTIPLIER * myshares;
215                                }
216                                else
217                                {
218                                        /* Increase for odd task and decrease for even task*/
219                                        if (my_group_num % 2)
220                                                myshares += baseshares * GRANULARITY / 100;
221                                        else
222                                                myshares -= baseshares * GRANULARITY / 100;
223                                }
224				write_to_file (mysharesfile, "w", myshares);
225				if (test_num == 3)
226				{
227				/*
228				 * Read the shares file and again calculate the cpu fraction
229				 * No need to read tasks file as we do not migrate tasks
230				 * No need to scan all shares file as total shares are const
231				 */
232				if ((fmyshares = read_shares_file(mysharesfile)) < 2)
233					tst_brkm (TBROK, cleanup, "in reading shares files  %s ", mysharesfile);
234				exp_cpu_time = (double)(fmyshares * 100) /(total_shares * num_tasks);
235				}
236
237				fprintf(stdout,"\ntask-%d SHARES=%lu\n",my_group_num, myshares);
238			}/* end if*/
239        }/* end while*/
240}/* end main*/
241
242