/*****************************************************************************/ /* */ /* 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 /* definitions for standard I/O */ #include /* required by usleep() */ #include /* definitions for errno */ #include /* definitions for sched_yield() */ #include /* definitions for WEXIT macros */ #include /* required by sigaction & sig handling fncs */ #include /* definitions of settimer() */ #include /* definitions of itimer structure */ #include /* definitions for pthread_create etc */ #include /* required by setjmp longjmp */ #include /* required by the signal handler */ #include /* required by shmat shmget etc */ #include /* required by shmat shmget etc */ #include /* 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; }