/*****************************************************************************/
/* */
/* Copyright (c) International Business Machines Corp., 2001 */
/* */
/* This program is free software; you can redistribute it and/or modify */
/* it under the terms of the GNU General Public License as published by */
/* the Free Software Foundation; either version 2 of the License, or */
/* (at your option) any later version. */
/* */
/* This program is distributed in the hope that it will be useful, */
/* but WITHOUT ANY WARRANTY; without even the implied warranty of */
/* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See */
/* the GNU General Public License for more details. */
/* */
/* You should have received a copy of the GNU General Public License */
/* along with this program; if not, write to the Free Software */
/* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */
/* */
/******************************************************************************/
/******************************************************************************/
/* */
/* History: July - 16 - 2001 Created by Manoj Iyer, IBM Austin TX. */
/* email:manjo@austin.ibm.com */
/* */
/* July - 30 - 2001 Modified - Added function write_to_mem. */
/* */
/* Aug - 14 - 2001 Modified - Added code to remove the shared */
/* memory segment ids. */
/* */
/* Aug - 15 - 2001 Modified - Added for loop to run the test */
/* repeatedly. */
/* */
/* Oct - 22 - 2001 Modified - Fixed bad code in main(). */
/* removed stray code and options. Pthread_join */
/* part fixed, older version was completely bad */
/* */
/* Nov - 09 - 2001 Modified - Removed compile errors */
/* - added missing header file string.h */
/* - removed unused variables. */
/* - made read_ndx and write_ndx static variable*/
/* */
/* Nov - 91 - 2001 Modified - Changed scope of status variable */
/* - change the status of status variable from */
/* int *status to int status[1] */
/* */
/* File: shmat1.c */
/* */
/* Description: Test the LINUX memory manager. The program is aimed at */
/* stressing the memory manager by repeaded shmat/write/read/ */
/* shmatd of file/memory of random size (maximum 1000 * 4096) */
/* done by multiple processes. */
/* */
/* Create a file of random size upto 1000 times 4096. */
/* process X shmats and un-shmats this file in memory. */
/* process Y changes content of the file to Y, ie writes to it. */
/* process Z reads from this memory location, and varifies the */
/* the content of the file. */
/* */
/******************************************************************************/
/* Include Files */
#include <stdio.h> /* definitions for standard I/O */
#include <unistd.h> /* required by usleep() */
#include <errno.h> /* definitions for errno */
#include <sched.h> /* definitions for sched_yield() */
#include <stdlib.h> /* definitions for WEXIT macros */
#include <signal.h> /* required by sigaction & sig handling fncs */
#include <sys/time.h> /* definitions of settimer() */
#include <sys/wait.h> /* definitions of itimer structure */
#include <pthread.h> /* definitions for pthread_create etc */
#include <setjmp.h> /* required by setjmp longjmp */
#include <sys/ucontext.h> /* required by the signal handler */
#include <sys/ipc.h> /* required by shmat shmget etc */
#include <sys/shm.h> /* required by shmat shmget etc */
#include <string.h> /* required by strncmp */
/* Defines */
#ifndef TRUE
#define TRUE 1
#endif
#ifndef FALSE
#define FALSE 0
#endif
#define prtln() printf(" I AM HERE ==> %s %d\n", __FILE__, __LINE__);
#define STR_SHMAT " "
#define STR_WRITER " "
#define STR_READER " "
/* Global Variables */
void *map_address; /* pointer to file in memory */
sigjmp_buf jmpbuf; /* argument to setjmp and longjmp */
int fsize; /* size of the file to be created. */
int done_shmat = 0; /* disallow read and writes before shmat */
/******************************************************************************/
/* */
/* Function: sig_handler */
/* */
/* Description: handle SIGALRM raised by set_timer(), SIGALRM is raised when */
/* the timer expires. If any other signal is received exit the */
/* test. */
/* */
/* Input: signal - signal number, intrested in SIGALRM! */
/* */
/* Return: exit -1 if unexpected signal is received */
/* exit 0 if SIGALRM is received */
/* */
/******************************************************************************/
static void sig_handler(int signal, /* signal number, set to handle SIGALRM */
int code, ucontext_t *ut)
{ /* contains pointer to sigcontext structure */
#ifdef __i386__
unsigned long except; /* exception type. */
int ret = 0; /* exit code from signal handler. */
struct sigcontext *scp = /* pointer to sigcontext structure */
(struct sigcontext *)&ut->uc_mcontext;
#endif
if (signal == SIGALRM) {
fprintf(stdout, "Test ended, success\n");
exit(0);
}
#ifdef __i386__
else {
except = scp->trapno;
fprintf(stderr, "signal caught - [%d] ", signal);
}
switch (except) {
case 10:
fprintf(stderr,
"Exception - invalid TSS, exception #[%ld]\n", except);
break;
case 11:
fprintf(stderr,
"Exception - segment not present, exception #[%ld]\n",
except);
break;
case 12:
fprintf(stderr,
"Exception - stack segment not present, exception #[%ld]\n",
except);
break;
case 13:
fprintf(stderr,
"Exception - general protection, exception #[%ld]\n",
except);
break;
case 14:
fprintf(stderr,
"Exception - page fault, exception #[%ld]\n", except);
ret = 1;
break;
default:
fprintf(stderr,
"Exception type not handled... unknown exception #[%ld]\n",
except);
break;
}
if (ret) {
if (scp->edi == (int)map_address) {
fprintf(stdout,
"page fault at [%#lx] - ignore\n", scp->edi);
siglongjmp(jmpbuf, 1);
} else if (scp->esi == (int)map_address) {
fprintf(stdout,
"page fault at [%#lx] - ignore\n", scp->esi);
siglongjmp(jmpbuf, 1);
} else {
fprintf(stderr,
"address at which sigfault occured: [%lx]\n"
"address at which sigfault occured: [%lx]\n"
"address at which memory was shmat: [%p]\n",
(unsigned long)scp->edi,
(unsigned long)scp->esi, map_address);
fprintf(stderr, "bad page fault exit test\n");
exit(-1);
}
} else
exit(-1);
#else
fprintf(stderr, "caught signal %d -- exiting.\n", signal);
exit(-1);
#endif
}
/******************************************************************************//* */
/* Function: usage */
/* */
/* Description: Print the usage message. */
/* */
/* Return: exits with -1 */
/* */
/******************************************************************************/
static void usage(char *progname)
{ /* name of this program */
fprintf(stderr,
"Usage: %s -h -l -x\n"
"\t -h help, usage message.\n"
"\t -l number of map - write - unmap. default: 1000\n"
"\t -x time for which test is to be run. default: 24 Hrs\n",
progname);
exit(-1);
}
/******************************************************************************/
/* */
/* Function: shmat_shmdt */
/* */
/* Description: Thread X function. */
/* shmat a random size file and shm-detach this file, this is */
/* done for user defined number of times. */
/* */
/* Input: arg[0] number of times shmat shmdt is done */
/* */
/* Return: -1 on error. */
/* 0 on errorless completion of the loop. */
/* */
/******************************************************************************/
void *shmat_shmdt(void *args)
{ /* arguments to the thread X function. */
int shm_ndx = 0; /* index to number of shmat/shmdt */
key_t shmkey = 0; /* IPC_PRIVATE (key for shmget) */
int shmid; /* shared memory id */
long *locargs = /* local pointer to arguments */
(long *)args;
while (shm_ndx++ < (int)locargs[0]) {
/* put the reader and writer threads to sleep */
done_shmat = 0;
/* generate a random size, we will ask for this amount of shared mem */
srand(time(NULL) % 100);
fsize = (1 + (int)(1000.0 * rand() / (RAND_MAX + 1.0))) * 4096;
if ((shmid = shmget(shmkey, fsize, IPC_CREAT | 0666)) == -1) {
perror("shmat_shmdt(): shmget()");
pthread_exit((void *)-1);
} else {
fprintf(stdout,
"%s[%#lx]: shmget(): success, got segment of size %d\n",
STR_SHMAT, pthread_self(), fsize);
}
if ((map_address = shmat(shmid, NULL, 0))
== (void *)-1) {
fprintf(stderr, "shmat_shmat(): map address = %p\n",
map_address);
perror("shmat_shmdt(): shmat()");
pthread_exit((void *)-1);
} else {
/* Wake up the reader and writer threads. */
/* Write 'X' into map_address. We are not sure about
reader/writer interleaving. So the reader may expect
to find 'X' or 'Y'
*/
memset(map_address, 'X', 1);
done_shmat = 1;
usleep(0);
}
fprintf(stdout, "%s[%#lx]: Map address = %p\n",
STR_SHMAT, pthread_self(), map_address);
fprintf(stdout,
"%s[%#lx]: Num iter: [%d] Total Num Iter: [%d]\n",
STR_SHMAT, pthread_self(), shm_ndx, (int)locargs[0]);
usleep(0);
sched_yield();
/* put the threads to sleep before un-shmatting */
done_shmat = 0;
if (shmdt((void *)map_address) == -1) {
perror("shmat_shmdt(): shmdt()");
pthread_exit((void *)-1);
}
if (shmctl(shmid, IPC_RMID, NULL)) {
perror("shmat_shmdt(): shmctl()");
pthread_exit((void *)-1);
}
}
pthread_exit(NULL);
}
/******************************************************************************/
/* */
/* Function: write_to_mem */
/* */
/* Description: Thread Y function. */
/* Writes 'Y' to the memory location shmat by process X. */
/* */
/* Input: arg[0] number of times write is performed */
/* */
/* Return: -1 on error. */
/* 0 on errorless completion of the loop. */
/* */
/******************************************************************************/
void *write_to_mem(void *args)
{
static int write_ndx = 0; /* index to the number of writes to perform */
long *locargs = /* local pointer to the arguments */
(long *)args;
while (write_ndx++ < (int)locargs[0]) {
/* wait for the thread to shmat, and dont sleep on the processor. */
while (!done_shmat)
usleep(0);
if (sigsetjmp(jmpbuf, 1) == 1) {
fprintf(stdout,
"page fault ocurred due a write after an shmdt from [%p]\n",
map_address);
}
fprintf(stdout,
"%s[%#lx]: write_to_mem(): memory address: [%p]\n",
STR_WRITER, pthread_self(), map_address);
memset(map_address, 'Y', 1);
usleep(1);
sched_yield();
}
pthread_exit(NULL);
}
/******************************************************************************/
/* */
/* Function: read_from_mem */
/* */
/* Description: Thread Z function. */
/* reads from the memory location shmat by process X. */
/* */
/* Input: arg[0] number of times read is performed */
/* */
/* Return: -1 on error. */
/* 0 on errorless completion of the loop. */
/* */
/******************************************************************************/
void *read_from_mem(void *args)
{
static int read_ndx = 0; /* index to the number of writes to perform */
long *locargs = /* local pointer to the arguments */
(long *)args;
while (read_ndx++ < (int)locargs[0]) {
/* wait for the shmat to happen */
while (!done_shmat)
usleep(0);
fprintf(stdout,
"%s[%#lx]: read_from_mem(): memory address: [%p]\n",
STR_READER, pthread_self(), map_address);
if (sigsetjmp(jmpbuf, 1) == 1) {
fprintf(stdout,
"page fault ocurred due a read after an shmdt from %p\n",
map_address);
}
fprintf(stdout, "%s[%#lx]: read_mem(): content of memory: %s\n",
STR_READER, pthread_self(), (char *)map_address);
if (strncmp(map_address, "Y", 1) != 0) {
if (strncmp(map_address, "X", 1) != 0) {
pthread_exit((void *)-1);
}
}
usleep(1);
sched_yield();
}
pthread_exit(NULL);
}
/******************************************************************************/
/* */
/* Function: main */
/* */
/* Descrption: Create a large file of size up to a Giga Bytes. write to it */
/* lower case alphabet 'a'. Map the file and change the contents */
/* to 'A's (upper case alphabet), write the contents to the file,*/
/* and unmap the file from memory. Spwan a certian number of */
/* LWP's that will do the above. */
/* */
/* Return: exits with -1 on error */
/* exits with a 0 on success. */
/* */
/******************************************************************************/
int main(int argc, /* number of input parameters. */
char **argv)
{ /* pointer to the command line arguments. */
int c; /* command line options */
int num_iter; /* number of iteration to perform */
int thrd_ndx; /* index into the array of threads. */
double exec_time; /* period for which the test is executed */
void *status; /* exit status for light weight process */
int sig_ndx; /* index into signal handler structure. */
pthread_t thid[1000]; /* pids of process that will map/write/unmap */
long chld_args[3]; /* arguments to funcs execed by child process */
extern char *optarg; /* arguments passed to each option */
struct sigaction sigptr; /* set up signal, for interval timer */
static struct signal_info {
int signum; /* signal number that hasto be handled */
char *signame; /* name of the signal to be handled. */
} sig_info[] = {
{
SIGHUP, "SIGHUP"}, {
SIGINT, "SIGINT"}, {
SIGQUIT, "SIGQUIT"}, {
SIGABRT, "SIGABRT"}, {
SIGBUS, "SIGBUS"}, {
SIGSEGV, "SIGSEGV"}, {
SIGALRM, "SIGALRM"}, {
SIGUSR1, "SIGUSR1"}, {
SIGUSR2, "SIGUSR2"}, {
-1, "ENDSIG"}
};
/* set up the default values */
num_iter = 1000; /* repeate map - write - unmap operation 1000 times */
exec_time = 24.0; /* minimum time period for which to run the tests */
while ((c = getopt(argc, argv, "h:l:x:")) != -1) {
switch (c) {
case 'h':
usage(argv[0]);
break;
case 'l': /* number of times to loop in the thread function */
if ((num_iter = atoi(optarg)) == 0)
num_iter = 1000;
break;
case 'x': /* time in hrs to run this test. */
if ((exec_time = atof(optarg)) == 0)
exec_time = 24;
break;
default:
usage(argv[0]);
break;
}
}
fprintf(stdout,
"\n\n\nTest is set to run with the following parameters:\n"
"\tDuration of test: [%f]hrs\n"
"\tnumber of shmat shm detach: [%d]\n", exec_time, num_iter);
/* set up signals */
sigptr.sa_handler = (void (*)(int signal))sig_handler;
sigfillset(&sigptr.sa_mask);
sigptr.sa_flags = SA_SIGINFO;
for (sig_ndx = 0; sig_info[sig_ndx].signum != -1; sig_ndx++) {
sigaddset(&sigptr.sa_mask, sig_info[sig_ndx].signum);
if (sigaction(sig_info[sig_ndx].signum, &sigptr,
NULL) == -1) {
perror("man(): sigaction()");
fprintf(stderr,
"could not set handler for SIGALRM, errno = %d\n",
errno);
exit(-1);
}
}
chld_args[0] = num_iter;
alarm(exec_time * 3600.00);
for (;;) {
/* create 3 threads */
if (pthread_create(&thid[0], NULL, shmat_shmdt, chld_args)) {
perror("main(): pthread_create()");
exit(-1);
} else {
fprintf(stdout,
"created thread id[%#lx], execs fn shmat_shmdt()\n",
thid[0]);
}
sched_yield();
if (pthread_create(&thid[1], NULL, write_to_mem, chld_args)) {
perror("main(): pthread_create()");
exit(-1);
} else {
fprintf(stdout,
"created thread id[%#lx], execs fn write_to_mem()\n",
thid[1]);
}
sched_yield();
if (pthread_create(&thid[2], NULL, read_from_mem, chld_args)) {
perror("main(): pthread_create()");
exit(-1);
} else {
fprintf(stdout,
"created thread id[%#lx], execs fn read_from_mem()\n",
thid[2]);
}
sched_yield();
/* wait for the children to terminate */
for (thrd_ndx = 0; thrd_ndx < 3; thrd_ndx++) {
if (pthread_join(thid[thrd_ndx], &status)) {
perror("main(): pthread_create()");
exit(-1);
}
if (status == (void *)-1) {
fprintf(stderr,
"thread [%#lx] - process exited with errors %ld\n",
thid[thrd_ndx], (long)status);
exit(-1);
}
}
}
fprintf(stdout, "TEST PASSED\n");
return 0;
}