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_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#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#include "safe_macros.h"
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 */
72char *TCID = "cpuctl_test01";
73int TST_TOTAL = 1;
74pid_t scriptpid;
75char path[] = "/dev/cpuctl";
76extern void cleanup(void)
77{
78	kill(scriptpid, SIGUSR1);	/* Inform the shell to do cleanup */
79	tst_exit();		/* Report exit status */
80}
81
82int main(int argc, char *argv[])
83{
84
85	int num_cpus;
86	int test_num;
87	int len;		/* Total time = TIME_INTERVAL *num_cpus in the machine */
88	char mygroup[FILENAME_MAX], mytaskfile[FILENAME_MAX];
89	char mysharesfile[FILENAME_MAX], ch;
90	pid_t pid;
91	gid_t my_group_num;	/* A number attached with a group */
92	int fd;			/* A descriptor to open a fifo for synchronized start */
93	int first_counter = 0;	/* To take n number of readings */
94	int second_counter = 0;	/* To track number of times the base value of shares has been changed */
95	double total_cpu_time,	/* Accumulated cpu time */
96	 delta_cpu_time,	/* Time the task could run on cpu(s) (in an interval) */
97	 prev_cpu_time = 0;
98	double exp_cpu_time;	/* Expected time in % as obtained 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;	/* Simply the base value to start with */
102	unsigned int fmyshares, num_tasks;	/* f-> from file. num_tasks is tasks in this group */
103	struct sigaction newaction, oldaction;
104
105	my_group_num = -1;
106	num_cpus = 0;
107	test_num = 0;
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
123	if (test_num == 1)	/* Test 01 & Test 02 */
124		myshares *= my_group_num;
125	else if (test_num == 3)	/* Test 03 */
126		myshares = baseshares;
127	else {
128		tst_brkm(TBROK, cleanup,
129			 "Wrong Test number passed. Exiting Test...");
130	}
131
132	sprintf(mygroup, "%s", argv[2]);
133	sprintf(mytaskfile, "%s", mygroup);
134	sprintf(mysharesfile, "%s", mygroup);
135	strcat(mytaskfile, "/tasks");
136	strcat(mysharesfile, "/cpu.shares");
137	pid = getpid();
138	write_to_file(mytaskfile, "a", pid);	/* Assign the task to it's group */
139	write_to_file(mysharesfile, "w", myshares);
140
141	fd = SAFE_OPEN(cleanup, "./myfifo", 0);
142
143	fprintf(stdout, "\ntask-%d SHARES=%lu\n", my_group_num, myshares);
144	read(fd, &ch, 1);	/* To block all tasks here and fire them up at the same time */
145
146	/*
147	 * We now calculate the expected % cpu time of this task by getting
148	 * it's group's shares, the total shares of all the groups and the
149	 * number of tasks 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, "Could not copy directory path %s ",
157			 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, "in reading shares files  %s ",
166			 mysharesfile);
167
168	if ((read_file(mytaskfile, GET_TASKS, &num_tasks)) < 0)
169		tst_brkm(TBROK, cleanup, "in reading tasks files  %s ",
170			 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		/* Need to run some cpu intensive task, which also frequently checks the timer value */
178		double f = 274.345, mytime;	/*just a float number to take sqrt */
179		alarm(TIME_INTERVAL);
180		timer_expired = 0;
181		while (!timer_expired)	/* Let the task run on cpu for TIME_INTERVAL */
182			f = sqrt(f * f);	/* Time of this operation should not be high otherwise we can
183						 * exceed the TIME_INTERVAL to measure cpu usage
184						 */
185		current_time = time(NULL);
186		delta_time = current_time - prev_time;	/* Duration in case its not exact TIME_INTERVAL */
187
188		getrusage(0, &cpu_usage);
189		total_cpu_time = (cpu_usage.ru_utime.tv_sec + cpu_usage.ru_utime.tv_usec * 1e-6 +	/*user */
190				  cpu_usage.ru_stime.tv_sec + cpu_usage.ru_stime.tv_usec * 1e-6);	/*sys */
191		delta_cpu_time = total_cpu_time - prev_cpu_time;
192
193		prev_cpu_time = total_cpu_time;
194		prev_time = current_time;
195
196		/* calculate % cpu time each task gets */
197		if (delta_time > TIME_INTERVAL)
198			mytime =
199			    (delta_cpu_time * 100) / (delta_time * num_cpus);
200		else
201			mytime =
202			    (delta_cpu_time * 100) / (TIME_INTERVAL * num_cpus);
203
204		fprintf(stdout, "task-%d:CPU TIME{calc:-%6.2f(s)i.e. %6.2f(%%) exp:-%6.2f(%%)}\
205with %lu(shares) in %lu (s) INTERVAL\n", my_group_num, delta_cpu_time, mytime,
206			exp_cpu_time, myshares, delta_time);
207		first_counter++;
208
209		if (first_counter >= NUM_INTERVALS) {	/* Take n sets of readings for each shares value */
210			first_counter = 0;
211			second_counter++;
212			if (second_counter >= NUM_SETS)
213				exit(0);	/* This task is done with its job */
214
215			/* Change share values depending on the test_num */
216			if (test_num == 1) {
217				/* Keep same ratio but change values */
218				myshares = MULTIPLIER * myshares;
219			} else {
220				/* Increase for odd task and decrease for even task */
221				if (my_group_num % 2)
222					myshares +=
223					    baseshares * GRANULARITY / 100;
224				else
225					myshares -=
226					    baseshares * GRANULARITY / 100;
227			}
228			write_to_file(mysharesfile, "w", myshares);
229			if (test_num == 3) {
230				/*
231				 * Read the shares file and again calculate the cpu fraction
232				 * No need to read tasks file as we do not migrate tasks
233				 * No need to scan all shares file as total shares are const
234				 */
235				if ((fmyshares =
236				     read_shares_file(mysharesfile)) < 2)
237					tst_brkm(TBROK, cleanup,
238						 "in reading shares files  %s ",
239						 mysharesfile);
240				exp_cpu_time =
241				    (double)(fmyshares * 100) / (total_shares *
242								 num_tasks);
243			}
244
245			fprintf(stdout, "\ntask-%d SHARES=%lu\n", my_group_num,
246				myshares);
247		}		/* end if */
248	}			/* end while */
249}				/* end main */
250