cpuctl_test02.c revision 4548c6cf9bcdd96d8303caa4130ab638b61f8a30 
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_test02.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 04:     Nice value effect on group scheduling                         */
33/* Test 05:     Task migration test                                           */
34/*                                                                            */
35/* Test Name:   cpu_controller_test02                                         */
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/* Standard Include Files */
48#include <unistd.h>
49#include <math.h>
50#include <signal.h>
51#include <stdio.h>
52#include <stdlib.h>
53#include <string.h>
54#include <sys/resource.h>
55#include <sys/syscall.h>
56#include <sys/time.h>
57#include <sys/types.h>
58#include <sys/stat.h>
59#include <fcntl.h>
60#include <time.h>
61#include <unistd.h>
62
63#include "../libcontrollers/libcontrollers.h"
64#include "test.h"		/* LTP harness APIs*/
65
66#define TIME_INTERVAL	30	/* Time interval in seconds*/
67#define NUM_INTERVALS	3       /* How many iterations of TIME_INTERVAL */
68
69char *TCID = "cpu_controller_test04";
70int TST_TOTAL = 1;
71pid_t scriptpid;
72char path[] = "/dev/cpuctl";
73
74extern void
75cleanup()
76{
77	kill (scriptpid, SIGUSR1);/* Inform the shell to do cleanup*/
78	tst_exit ();		/* Report exit status*/
79}
80
81int migrate_task ();
82volatile int timer_expired = 0;
83
84int main(int argc, char* argv[])
85{
86
87	int test_num;
88	int task_num;
89	int len;
90	int num_cpus;	/* Total time = TIME_INTERVAL *num_cpus in the machine */
91	int migrate=0;			/* For task migration*/
92	char mygroup[FILENAME_MAX], mytaskfile[FILENAME_MAX];
93	char mysharesfile[FILENAME_MAX], ch;
94	/* Following variables are to capture parameters from script*/
95	char *group_num_p, *mygroup_p, *script_pid_p, *num_cpus_p, *test_num_p, *task_num_p;
96	pid_t pid;
97	gid_t mygroup_num;	        /* A number attached with a group*/
98	int fd;          	        /* A descriptor to open a fifo for synchronized start*/
99	int counter =0; 	 	/* To take n number of readings*/
100	double total_cpu_time,  	/* Accumulated cpu time*/
101		delta_cpu_time,  	/* Time the task could run on cpu(s) (in an interval)*/
102		prev_cpu_time=0;
103        double exp_cpu_time;            /* Expected time in % as obtained by shares calculation */
104
105	struct rusage cpu_usage;
106	time_t current_time, prev_time, delta_time;
107        unsigned int fmyshares, num_tasks;/* f-> from file. num_tasks is tasks in this group*/
108	struct sigaction newaction, oldaction;
109
110	mygroup_num = -1;
111	num_cpus = 0;
112	task_num = 0;
113	test_num = 0;
114
115	/* Signal handling for alarm*/
116	sigemptyset (&newaction.sa_mask);
117	newaction.sa_handler = signal_handler_alarm;
118	newaction.sa_flags=0;
119	sigaction (SIGALRM, &newaction, &oldaction);
120
121	/* Collect the parameters passed by the script */
122	group_num_p	= getenv("GROUP_NUM");
123	mygroup_p	= getenv("MYGROUP");
124	script_pid_p 	= getenv("SCRIPT_PID");
125	num_cpus_p 	= getenv("NUM_CPUS");
126	test_num_p 	= getenv("TEST_NUM");
127	task_num_p 	= getenv("TASK_NUM");
128	/* Check if all of them are valid */
129	if ((test_num_p != NULL) && (((test_num = atoi(test_num_p)) == 4) || ((test_num =atoi(test_num_p)) == 5)))
130	{
131		if ((group_num_p != NULL) && (mygroup_p != NULL) && \
132			(script_pid_p != NULL) && (num_cpus_p != NULL) && (task_num_p != NULL))
133		{
134			mygroup_num	 = atoi(group_num_p);
135			scriptpid	 = atoi(script_pid_p);
136			num_cpus	 = atoi (num_cpus_p);
137			task_num	 = atoi (task_num_p);
138			sprintf(mygroup,"%s", mygroup_p);
139		}
140		else
141		{
142			tst_brkm (TBROK, cleanup, "Invalid other input parameters\n");
143		}
144	}
145	else
146	{
147		tst_brkm (TBROK, cleanup, "Invalid test number passed\n");
148	}
149
150	sprintf(mytaskfile, "%s", mygroup);
151	sprintf(mysharesfile, "%s", mygroup);
152	strcat (mytaskfile,"/tasks");
153	strcat (mysharesfile,"/cpu.shares");
154	pid = getpid();
155	write_to_file (mytaskfile, "a", pid);    /* Assign the task to it's group*/
156
157	fd = open ("./myfifo", 0);
158	if (fd == -1)
159	{
160		tst_brkm (TBROK, cleanup, "Could not open fifo for synchronization");
161	}
162
163	read (fd, &ch, 1);	         /* To block all tasks here and fire them up at the same time*/
164
165	/*
166	 * We now calculate the expected % cpu time of this task by getting
167	 * it's group's shares, the total shares of all the groups and the
168	 * number of tasks in this group.
169	 */
170	FLAG = 0;
171	total_shares = 0;
172	shares_pointer = &total_shares;
173	len = strlen (path);
174	if (!strncpy (fullpath, path, len))
175		tst_brkm (TBROK, cleanup, "Could not copy directory path %s ", path);
176
177	if (scan_shares_files(shares_pointer) != 0)
178		tst_brkm (TBROK, cleanup, "From function scan_shares_files in %s ", fullpath);
179
180	/* return val: -1 in case of function error, else 2 is min share value */
181	if ((fmyshares = read_shares_file(mysharesfile)) < 2)
182		tst_brkm (TBROK, cleanup, "in reading shares files  %s ", mysharesfile);
183
184	if ((read_file (mytaskfile, GET_TASKS, &num_tasks)) < 0)
185		tst_brkm (TBROK, cleanup, "in reading tasks files  %s ", mytaskfile);
186
187	exp_cpu_time = (double)(fmyshares * 100) /(total_shares * num_tasks);
188
189	prev_time = time (NULL);	 /* Note down the time*/
190
191	while (1)
192	{
193		/* Need to run some cpu intensive task, which also frequently checks the timer value*/
194		double f = 274.345, mytime;	/*just a float number to take sqrt*/
195		alarm (TIME_INTERVAL);
196		timer_expired = 0;
197		while (!timer_expired)	/* Let the task run on cpu for TIME_INTERVAL*/
198			f = sqrt (f*f); /* Time of this operation should not be high otherwise we can
199					 * exceed the TIME_INTERVAL to measure cpu usage
200					 */
201		current_time = time (NULL);
202		delta_time = current_time - prev_time;	/* Duration in case its not exact TIME_INTERVAL*/
203
204		getrusage (0, &cpu_usage);
205		total_cpu_time = (cpu_usage.ru_utime.tv_sec + cpu_usage.ru_utime.tv_usec * 1e-6 + /* user time*/
206				cpu_usage.ru_stime.tv_sec + cpu_usage.ru_stime.tv_usec * 1e-6) ;  /* system time*/
207		delta_cpu_time = total_cpu_time - prev_cpu_time;
208
209		prev_cpu_time = total_cpu_time;
210		prev_time = current_time;
211
212		/* calculate % cpu time each task gets */
213		if (delta_time > TIME_INTERVAL)
214			mytime =  (delta_cpu_time * 100) / (delta_time * num_cpus);
215		else
216			mytime =  (delta_cpu_time * 100) / (TIME_INTERVAL * num_cpus);
217
218                fprintf (stdout,"Grp:-%3d task-%3d:CPU TIME{calc:-%6.2f(s)i.e. %6.2f(%%)exp:-%6.2f(%%)}\
219with %u(shares) in %lu (s) INTERVAL\n",mygroup_num, task_num, delta_cpu_time, mytime,\
220exp_cpu_time, fmyshares, delta_time);
221
222		counter++;
223
224		if (counter >= NUM_INTERVALS)	 /* Take n sets of readings for each shares value*/
225		{
226		switch (test_num)
227			{
228			case 4:			/* Test04 */
229				exit (0);	/* This task is done with its job*/
230				break;
231			case 5:			/* Test 05 */
232				if (migrate == 0)
233				{
234					counter = 0;
235					fprintf (stdout, "FIRST RUN COMPLETED FOR TASK %d\n", task_num);
236					migrate = 1;
237				}
238				else
239				{
240					fprintf (stdout, "SECOND RUN COMPLETED FOR TASK %d\n", task_num);
241					exit (0);
242				}
243				break;
244			default:
245				tst_brkm (TBROK, cleanup, "Invalid test number passed\n");
246				break;
247
248			}	/* end switch*/
249		}
250		if ((migrate == 1) && (counter == 0))
251		{
252			if (task_num == 1)
253			{
254				if (migrate_task() != 0)
255					tst_brkm (TFAIL, cleanup, "Could not migrate task 1 ");
256				else
257					fprintf (stdout, "TASK 1 MIGRATED FROM GROUP 1 TO GROUP 2\n");
258				strcpy (mytaskfile, "/dev/cpuctl/group_2/tasks");
259			}
260			/*
261			 * Read the shares files and again calculate the cpu fraction
262			 * In test 2(case 4) we need to read tasks file as we migrate task
263			 * Q?? How to ensure other tasks do not read before task 1 migration
264			 */
265			if ((read_file (mytaskfile, GET_TASKS, &num_tasks)) < 0)
266				tst_brkm (TBROK, cleanup, "in reading tasks files  %s ", mytaskfile);
267			exp_cpu_time = (double)(fmyshares * 100) /(total_shares * num_tasks);
268		}
269        }	/* end while*/
270}	/* end main*/
271
272int migrate_task ()
273{
274	char target[32] = "/dev/cpuctl/group_2/tasks";/* Hard coding..Will try dynamic*/
275	pid_t pid = getpid();
276	return (write_to_file (target, "a", pid));
277}
278