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diff --git a/test/time-sem.c b/test/time-sem.c
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+/* Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/*
+time-sem.c has the basics of the semaphores we use in http_main.c. It's
+intended for timing differences between various methods on an
+architecture. In practice we've found many things affect which semaphore
+to be used:
+
+ - NFS filesystems absolutely suck for fcntl() and flock()
+
+ - uslock absolutely sucks on single-processor IRIX boxes, but
+ absolutely rocks on multi-processor boxes. The converse
+ is true for fcntl. sysvsem seems a moderate balance.
+
+ - Under Solaris you can't have too many processes use SEM_UNDO, there
+ might be a tuneable somewhere that increases the limit from 29.
+ We're not sure what the tunable is, so there's a define
+ NO_SEM_UNDO which can be used to simulate us trapping/blocking
+ signals to be able to properly release the semaphore on a clean
+ child death. You'll also need to define NEED_UNION_SEMUN
+ under solaris.
+
+You'll need to define USE_SHMGET_SCOREBOARD if anonymous shared mmap()
+doesn't work on your system (i.e. linux).
+
+argv[1] is the #children, argv[2] is the #iterations per child
+
+You should run each over many different #children inputs, and choose
+#iter such that the program runs for at least a second or so... or even
+longer depending on your patience.
+
+compile with:
+
+gcc -o time-FCNTL -Wall -O time-sem.c -DUSE_FCNTL_SERIALIZED_ACCEPT
+gcc -o time-FLOCK -Wall -O time-sem.c -DUSE_FLOCK_SERIALIZED_ACCEPT
+gcc -o time-SYSVSEM -Wall -O time-sem.c -DUSE_SYSVSEM_SERIALIZED_ACCEPT
+gcc -o time-SYSVSEM2 -Wall -O time-sem.c -DUSE_SYSVSEM_SERIALIZED_ACCEPT -DNO_SEM_UNDO
+gcc -o time-PTHREAD -Wall -O time-sem.c -DUSE_PTHREAD_SERIALIZED_ACCEPT -lpthread
+gcc -o time-USLOCK -Wall -O time-sem.c -DUSE_USLOCK_SERIALIZED_ACCEPT
+
+not all versions work on all systems.
+*/
+
+#include <errno.h>
+#include <sys/time.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <sys/wait.h>
+#include <sys/mman.h>
+#include <signal.h>
+
+#if defined(USE_FCNTL_SERIALIZED_ACCEPT)
+
+static struct flock lock_it;
+static struct flock unlock_it;
+
+static int fcntl_fd=-1;
+
+#define accept_mutex_child_init()
+#define accept_mutex_cleanup()
+
+/*
+ * Initialize mutex lock.
+ * Must be safe to call this on a restart.
+ */
+void
+accept_mutex_init(void)
+{
+
+ lock_it.l_whence = SEEK_SET; /* from current point */
+ lock_it.l_start = 0; /* -"- */
+ lock_it.l_len = 0; /* until end of file */
+ lock_it.l_type = F_WRLCK; /* set exclusive/write lock */
+ lock_it.l_pid = 0; /* pid not actually interesting */
+ unlock_it.l_whence = SEEK_SET; /* from current point */
+ unlock_it.l_start = 0; /* -"- */
+ unlock_it.l_len = 0; /* until end of file */
+ unlock_it.l_type = F_UNLCK; /* set exclusive/write lock */
+ unlock_it.l_pid = 0; /* pid not actually interesting */
+
+ printf("opening test-lock-thing in current directory\n");
+ fcntl_fd = open("test-lock-thing", O_CREAT | O_WRONLY | O_EXCL, 0644);
+ if (fcntl_fd == -1)
+ {
+ perror ("open");
+ fprintf (stderr, "Cannot open lock file: %s\n", "test-lock-thing");
+ exit (1);
+ }
+ unlink("test-lock-thing");
+}
+
+void accept_mutex_on(void)
+{
+ int ret;
+
+ while ((ret = fcntl(fcntl_fd, F_SETLKW, &lock_it)) < 0 && errno == EINTR)
+ continue;
+
+ if (ret < 0) {
+ perror ("fcntl lock_it");
+ exit(1);
+ }
+}
+
+void accept_mutex_off(void)
+{
+ if (fcntl (fcntl_fd, F_SETLKW, &unlock_it) < 0)
+ {
+ perror ("fcntl unlock_it");
+ exit(1);
+ }
+}
+
+#elif defined(USE_FLOCK_SERIALIZED_ACCEPT)
+
+#include <sys/file.h>
+
+static int flock_fd=-1;
+
+#define FNAME "test-lock-thing"
+
+/*
+ * Initialize mutex lock.
+ * Must be safe to call this on a restart.
+ */
+void accept_mutex_init(void)
+{
+
+ printf("opening " FNAME " in current directory\n");
+ flock_fd = open(FNAME, O_CREAT | O_WRONLY | O_EXCL, 0644);
+ if (flock_fd == -1)
+ {
+ perror ("open");
+ fprintf (stderr, "Cannot open lock file: %s\n", "test-lock-thing");
+ exit (1);
+ }
+}
+
+void accept_mutex_child_init(void)
+{
+ flock_fd = open(FNAME, O_WRONLY, 0600);
+ if (flock_fd == -1) {
+ perror("open");
+ exit(1);
+ }
+}
+
+void accept_mutex_cleanup(void)
+{
+ unlink(FNAME);
+}
+
+void accept_mutex_on(void)
+{
+ int ret;
+
+ while ((ret = flock(flock_fd, LOCK_EX)) < 0 && errno == EINTR)
+ continue;
+
+ if (ret < 0) {
+ perror ("flock(LOCK_EX)");
+ exit(1);
+ }
+}
+
+void accept_mutex_off(void)
+{
+ if (flock (flock_fd, LOCK_UN) < 0)
+ {
+ perror ("flock(LOCK_UN)");
+ exit(1);
+ }
+}
+
+#elif defined (USE_SYSVSEM_SERIALIZED_ACCEPT)
+
+#include <sys/types.h>
+#include <sys/ipc.h>
+#include <sys/sem.h>
+
+static int sem_id = -1;
+#ifdef NO_SEM_UNDO
+static sigset_t accept_block_mask;
+static sigset_t accept_previous_mask;
+#endif
+
+#define accept_mutex_child_init()
+#define accept_mutex_cleanup()
+
+void accept_mutex_init(void)
+{
+#ifdef NEED_UNION_SEMUN
+ /* believe it or not, you need to define this under solaris */
+ union semun {
+ int val;
+ struct semid_ds *buf;
+ ushort *array;
+ };
+#endif
+
+ union semun ick;
+
+ sem_id = semget(999, 1, IPC_CREAT | 0666);
+ if (sem_id < 0) {
+ perror ("semget");
+ exit (1);
+ }
+ ick.val = 1;
+ if (semctl(sem_id, 0, SETVAL, ick) < 0) {
+ perror ("semctl");
+ exit(1);
+ }
+#ifdef NO_SEM_UNDO
+ sigfillset(&accept_block_mask);
+ sigdelset(&accept_block_mask, SIGHUP);
+ sigdelset(&accept_block_mask, SIGTERM);
+ sigdelset(&accept_block_mask, SIGUSR1);
+#endif
+}
+
+void accept_mutex_on()
+{
+ struct sembuf op;
+
+#ifdef NO_SEM_UNDO
+ if (sigprocmask(SIG_BLOCK, &accept_block_mask, &accept_previous_mask)) {
+ perror("sigprocmask(SIG_BLOCK)");
+ exit (1);
+ }
+ op.sem_flg = 0;
+#else
+ op.sem_flg = SEM_UNDO;
+#endif
+ op.sem_num = 0;
+ op.sem_op = -1;
+ if (semop(sem_id, &op, 1) < 0) {
+ perror ("accept_mutex_on");
+ exit (1);
+ }
+}
+
+void accept_mutex_off()
+{
+ struct sembuf op;
+
+ op.sem_num = 0;
+ op.sem_op = 1;
+#ifdef NO_SEM_UNDO
+ op.sem_flg = 0;
+#else
+ op.sem_flg = SEM_UNDO;
+#endif
+ if (semop(sem_id, &op, 1) < 0) {
+ perror ("accept_mutex_off");
+ exit (1);
+ }
+#ifdef NO_SEM_UNDO
+ if (sigprocmask(SIG_SETMASK, &accept_previous_mask, NULL)) {
+ perror("sigprocmask(SIG_SETMASK)");
+ exit (1);
+ }
+#endif
+}
+
+#elif defined (USE_PTHREAD_SERIALIZED_ACCEPT)
+
+/* note: pthread mutexes aren't released on child death, hence the
+ * signal goop ... in a real implementation we'd do special things
+ * during hup, term, usr1.
+ */
+
+#include <pthread.h>
+
+static pthread_mutex_t *mutex;
+static sigset_t accept_block_mask;
+static sigset_t accept_previous_mask;
+
+#define accept_mutex_child_init()
+#define accept_mutex_cleanup()
+
+void accept_mutex_init(void)
+{
+ pthread_mutexattr_t mattr;
+ int fd;
+
+ fd = open ("/dev/zero", O_RDWR);
+ if (fd == -1) {
+ perror ("open(/dev/zero)");
+ exit (1);
+ }
+ mutex = (pthread_mutex_t *)mmap ((caddr_t)0, sizeof (*mutex),
+ PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
+ if (mutex == (void *)(caddr_t)-1) {
+ perror ("mmap");
+ exit (1);
+ }
+ close (fd);
+ if (pthread_mutexattr_init(&mattr)) {
+ perror ("pthread_mutexattr_init");
+ exit (1);
+ }
+ if (pthread_mutexattr_setpshared(&mattr, PTHREAD_PROCESS_SHARED)) {
+ perror ("pthread_mutexattr_setpshared");
+ exit (1);
+ }
+ if (pthread_mutex_init(mutex, &mattr)) {
+ perror ("pthread_mutex_init");
+ exit (1);
+ }
+ sigfillset(&accept_block_mask);
+ sigdelset(&accept_block_mask, SIGHUP);
+ sigdelset(&accept_block_mask, SIGTERM);
+ sigdelset(&accept_block_mask, SIGUSR1);
+}
+
+void accept_mutex_on()
+{
+ if (sigprocmask(SIG_BLOCK, &accept_block_mask, &accept_previous_mask)) {
+ perror("sigprocmask(SIG_BLOCK)");
+ exit (1);
+ }
+ if (pthread_mutex_lock (mutex)) {
+ perror ("pthread_mutex_lock");
+ exit (1);
+ }
+}
+
+void accept_mutex_off()
+{
+ if (pthread_mutex_unlock (mutex)) {
+ perror ("pthread_mutex_unlock");
+ exit (1);
+ }
+ if (sigprocmask(SIG_SETMASK, &accept_previous_mask, NULL)) {
+ perror("sigprocmask(SIG_SETMASK)");
+ exit (1);
+ }
+}
+
+#elif defined (USE_USLOCK_SERIALIZED_ACCEPT)
+
+#include <ulocks.h>
+
+static usptr_t *us = NULL;
+static ulock_t uslock = NULL;
+
+#define accept_mutex_child_init()
+#define accept_mutex_cleanup()
+
+void accept_mutex_init(void)
+{
+ ptrdiff_t old;
+ /* default is 8 */
+#define CONF_INITUSERS_MAX 15
+ if ((old = usconfig(CONF_INITUSERS, CONF_INITUSERS_MAX)) == -1) {
+ perror("usconfig");
+ exit(-1);
+ }
+ if ((old = usconfig(CONF_LOCKTYPE, US_NODEBUG)) == -1) {
+ perror("usconfig");
+ exit(-1);
+ }
+ if ((old = usconfig(CONF_ARENATYPE, US_SHAREDONLY)) == -1) {
+ perror("usconfig");
+ exit(-1);
+ }
+ if ((us = usinit("/dev/zero")) == NULL) {
+ perror("usinit");
+ exit(-1);
+ }
+ if ((uslock = usnewlock(us)) == NULL) {
+ perror("usnewlock");
+ exit(-1);
+ }
+}
+void accept_mutex_on()
+{
+ switch(ussetlock(uslock)) {
+ case 1:
+ /* got lock */
+ break;
+ case 0:
+ fprintf(stderr, "didn't get lock\n");
+ exit(-1);
+ case -1:
+ perror("ussetlock");
+ exit(-1);
+ }
+}
+void accept_mutex_off()
+{
+ if (usunsetlock(uslock) == -1) {
+ perror("usunsetlock");
+ exit(-1);
+ }
+}
+#endif
+
+
+#ifndef USE_SHMGET_SCOREBOARD
+static void *get_shared_mem(apr_size_t size)
+{
+ void *result;
+
+ /* allocate shared memory for the shared_counter */
+ result = (unsigned long *)mmap ((caddr_t)0, size,
+ PROT_READ|PROT_WRITE, MAP_ANON|MAP_SHARED, -1, 0);
+ if (result == (void *)(caddr_t)-1) {
+ perror ("mmap");
+ exit (1);
+ }
+ return result;
+}
+#else
+#include <sys/types.h>
+#include <sys/ipc.h>
+#ifdef HAVE_SYS_MUTEX_H
+#include <sys/mutex.h>
+#endif
+#include <sys/shm.h>
+
+static void *get_shared_mem(apr_size_t size)
+{
+ key_t shmkey = IPC_PRIVATE;
+ int shmid = -1;
+ void *result;
+#ifdef MOVEBREAK
+ char *obrk;
+#endif
+
+ if ((shmid = shmget(shmkey, size, IPC_CREAT | SHM_R | SHM_W)) == -1) {
+ perror("shmget");
+ exit(1);
+ }
+
+#ifdef MOVEBREAK
+ /*
+ * Some SysV systems place the shared segment WAY too close
+ * to the dynamic memory break point (sbrk(0)). This severely
+ * limits the use of malloc/sbrk in the program since sbrk will
+ * refuse to move past that point.
+ *
+ * To get around this, we move the break point "way up there",
+ * attach the segment and then move break back down. Ugly
+ */
+ if ((obrk = sbrk(MOVEBREAK)) == (char *) -1) {
+ perror("sbrk");
+ }
+#endif
+
+#define BADSHMAT ((void *)(-1))
+ if ((result = shmat(shmid, 0, 0)) == BADSHMAT) {
+ perror("shmat");
+ }
+ /*
+ * We must avoid leaving segments in the kernel's
+ * (small) tables.
+ */
+ if (shmctl(shmid, IPC_RMID, NULL) != 0) {
+ perror("shmctl(IPC_RMID)");
+ }
+ if (result == BADSHMAT) /* now bailout */
+ exit(1);
+
+#ifdef MOVEBREAK
+ if (obrk == (char *) -1)
+ return; /* nothing else to do */
+ if (sbrk(-(MOVEBREAK)) == (char *) -1) {
+ perror("sbrk 2");
+ }
+#endif
+ return result;
+}
+#endif
+
+#ifdef _POSIX_PRIORITY_SCHEDULING
+/* don't ask */
+#define _P __P
+#include <sched.h>
+#define YIELD sched_yield()
+#else
+#define YIELD do { struct timeval zero; zero.tv_sec = zero.tv_usec = 0; select(0,0,0,0,&zero); } while(0)
+#endif
+
+void main (int argc, char **argv)
+{
+ int num_iter;
+ int num_child;
+ int i;
+ struct timeval first;
+ struct timeval last;
+ long ms;
+ int pid;
+ unsigned long *shared_counter;
+
+ if (argc != 3) {
+ fprintf (stderr, "Usage: time-sem num-child num iter\n");
+ exit (1);
+ }
+
+ num_child = atoi (argv[1]);
+ num_iter = atoi (argv[2]);
+
+ /* allocate shared memory for the shared_counter */
+ shared_counter = get_shared_mem(sizeof(*shared_counter));
+
+ /* initialize counter to 0 */
+ *shared_counter = 0;
+
+ accept_mutex_init ();
+
+ /* parent grabs mutex until done spawning children */
+ accept_mutex_on ();
+
+ for (i = 0; i < num_child; ++i) {
+ pid = fork();
+ if (pid == 0) {
+ /* child, do our thing */
+ accept_mutex_child_init();
+ for (i = 0; i < num_iter; ++i) {
+ unsigned long tmp;
+
+ accept_mutex_on ();
+ tmp = *shared_counter;
+ YIELD;
+ *shared_counter = tmp + 1;
+ accept_mutex_off ();
+ }
+ exit (0);
+ } else if (pid == -1) {
+ perror ("fork");
+ exit (1);
+ }
+ }
+
+ /* a quick test to see that nothing is screwed up */
+ if (*shared_counter != 0) {
+ puts ("WTF! shared_counter != 0 before the children have been started!");
+ exit (1);
+ }
+
+ gettimeofday (&first, NULL);
+ /* launch children into action */
+ accept_mutex_off ();
+ for (i = 0; i < num_child; ++i) {
+ if (wait(NULL) == -1) {
+ perror ("wait");
+ }
+ }
+ gettimeofday (&last, NULL);
+
+ if (*shared_counter != num_child * num_iter) {
+ printf ("WTF! shared_counter != num_child * num_iter!\n"
+ "shared_counter = %lu\nnum_child = %d\nnum_iter=%d\n",
+ *shared_counter,
+ num_child, num_iter);
+ }
+
+ last.tv_sec -= first.tv_sec;
+ ms = last.tv_usec - first.tv_usec;
+ if (ms < 0) {
+ --last.tv_sec;
+ ms += 1000000;
+ }
+ last.tv_usec = ms;
+ printf ("%8lu.%06lu\n", last.tv_sec, last.tv_usec);
+
+ accept_mutex_cleanup();
+
+ exit(0);
+}
+
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