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Posted to cvs@httpd.apache.org by tr...@locus.apache.org on 2000/06/09 16:49:02 UTC
cvs commit: apache-2.0/src/modules/mpm/prefork prefork.c
trawick 00/06/09 07:49:00
Modified: src CHANGES
src/modules/mpm/prefork prefork.c
Log:
The prefork MPM now uses an APR lock for the accept() mutex.
It has not been getting a lock at all recently.
Note: The TPF and SGI folks need to each APR how to get the most
efficient lock on those platforms. (For SGI it depends on whether
or not we're building for SMP.)
Revision Changes Path
1.144 +3 -0 apache-2.0/src/CHANGES
Index: CHANGES
===================================================================
RCS file: /home/cvs/apache-2.0/src/CHANGES,v
retrieving revision 1.143
retrieving revision 1.144
diff -u -r1.143 -r1.144
--- CHANGES 2000/06/07 12:36:50 1.143
+++ CHANGES 2000/06/09 14:48:55 1.144
@@ -1,4 +1,7 @@
Changes with Apache 2.0a5
+ *) The prefork MPM now uses an APR lock for the accept() mutex.
+ It has not been getting a lock at all recently. [Jeff Trawick]
+
*) Change the mmap() feature test to check only for existence.
The previous check required features not used by Apache.
[Greg Ames]
1.97 +13 -518 apache-2.0/src/modules/mpm/prefork/prefork.c
Index: prefork.c
===================================================================
RCS file: /home/cvs/apache-2.0/src/modules/mpm/prefork/prefork.c,v
retrieving revision 1.96
retrieving revision 1.97
diff -u -r1.96 -r1.97
--- prefork.c 2000/06/08 00:28:33 1.96
+++ prefork.c 2000/06/09 14:48:58 1.97
@@ -120,6 +120,7 @@
static int ap_max_requests_per_child=0;
static char *ap_pid_fname=NULL;
+static ap_lock_t *accept_lock;
static char *ap_scoreboard_fname=NULL;
static char *ap_lock_fname;
static int ap_daemons_to_start=0;
@@ -226,552 +227,46 @@
exit(code);
}
-#if defined(USE_FCNTL_SERIALIZED_ACCEPT) || defined(USE_FLOCK_SERIALIZED_ACCEPT)
static void expand_lock_fname(ap_pool_t *p)
{
/* XXXX possibly bogus cast */
ap_lock_fname = ap_psprintf(p, "%s.%lu",
ap_server_root_relative(p, ap_lock_fname), (unsigned long)getpid());
}
-#endif
-
-#if defined (USE_USLOCK_SERIALIZED_ACCEPT)
-
-#include <ulocks.h>
-
-static ulock_t uslock = NULL;
-
-#define accept_mutex_child_init(x)
-
-static void accept_mutex_init(ap_pool_t *p)
-{
- ptrdiff_t old;
- usptr_t *us;
-
-
- /* default is 8, allocate enough for all the children plus the parent */
- if ((old = usconfig(CONF_INITUSERS, HARD_SERVER_LIMIT + 1)) == -1) {
- perror("usconfig(CONF_INITUSERS)");
- exit(-1);
- }
-
- if ((old = usconfig(CONF_LOCKTYPE, US_NODEBUG)) == -1) {
- perror("usconfig(CONF_LOCKTYPE)");
- exit(-1);
- }
- if ((old = usconfig(CONF_ARENATYPE, US_SHAREDONLY)) == -1) {
- perror("usconfig(CONF_ARENATYPE)");
- exit(-1);
- }
- if ((us = usinit("/dev/zero")) == NULL) {
- perror("usinit");
- exit(-1);
- }
-
- if ((uslock = usnewlock(us)) == NULL) {
- perror("usnewlock");
- exit(-1);
- }
-}
-
-static void accept_mutex_on(void)
-{
- switch (ussetlock(uslock)) {
- case 1:
- /* got lock */
- break;
- case 0:
- ap_log_error(APLOG_MARK, APLOG_STARTUP | APLOG_NOERRNO, 0, NULL,
- "didn't get lock");
- clean_child_exit(APEXIT_CHILDFATAL);
- case -1:
- perror("ussetlock");
- clean_child_exit(APEXIT_CHILDFATAL);
- }
-}
-
-static void accept_mutex_off(void)
-{
- if (usunsetlock(uslock) == -1) {
- perror("usunsetlock");
- clean_child_exit(APEXIT_CHILDFATAL);
- }
-}
-
-#elif defined (USE_PTHREAD_SERIALIZED_ACCEPT)
-
-/* This code probably only works on Solaris ... but it works really fast
- * on Solaris. Note that pthread mutexes are *NOT* released when a task
- * dies ... the task has to free it itself. So we block signals and
- * try to be nice about releasing the mutex.
- */
-
-#include <pthread.h>
-
-static pthread_mutex_t *accept_mutex = (void *)(caddr_t) -1;
-static int have_accept_mutex;
-static sigset_t accept_block_mask;
-static sigset_t accept_previous_mask;
-
-static void accept_mutex_child_cleanup(void *foo)
-{
- if (accept_mutex != (void *)(caddr_t)-1
- && have_accept_mutex) {
- pthread_mutex_unlock(accept_mutex);
- }
-}
-
-static void accept_mutex_child_init(ap_pool_t *p)
-{
- ap_register_cleanup(p, NULL, accept_mutex_child_cleanup, ap_null_cleanup);
-}
-
-static void accept_mutex_cleanup(void *foo)
-{
- if (accept_mutex != (void *)(caddr_t)-1
- && munmap((caddr_t) accept_mutex, sizeof(*accept_mutex))) {
- perror("munmap");
- }
- accept_mutex = (void *)(caddr_t)-1;
-}
-
-static void accept_mutex_init(ap_pool_t *p)
-{
- pthread_mutexattr_t mattr;
- int fd;
-
- fd = open("/dev/zero", O_RDWR);
- if (fd == -1) {
- perror("open(/dev/zero)");
- exit(APEXIT_INIT);
- }
- accept_mutex = (pthread_mutex_t *) mmap((caddr_t) 0, sizeof(*accept_mutex),
- PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
- if (accept_mutex == (void *) (caddr_t) - 1) {
- perror("mmap");
- exit(APEXIT_INIT);
- }
- close(fd);
- if ((errno = pthread_mutexattr_init(&mattr))) {
- perror("pthread_mutexattr_init");
- exit(APEXIT_INIT);
- }
- if ((errno = pthread_mutexattr_setpshared(&mattr,
- PTHREAD_PROCESS_SHARED))) {
- perror("pthread_mutexattr_setpshared");
- exit(APEXIT_INIT);
- }
- if ((errno = pthread_mutex_init(accept_mutex, &mattr))) {
- perror("pthread_mutex_init");
- exit(APEXIT_INIT);
- }
- sigfillset(&accept_block_mask);
- sigdelset(&accept_block_mask, SIGHUP);
- sigdelset(&accept_block_mask, SIGTERM);
- sigdelset(&accept_block_mask, SIGUSR1);
- ap_register_cleanup(p, NULL, accept_mutex_cleanup, ap_null_cleanup);
-}
-
-static void accept_mutex_on(void)
-{
- int err;
-
- if (sigprocmask(SIG_BLOCK, &accept_block_mask, &accept_previous_mask)) {
- perror("sigprocmask(SIG_BLOCK)");
- clean_child_exit(APEXIT_CHILDFATAL);
- }
- if ((err = pthread_mutex_lock(accept_mutex))) {
- errno = err;
- perror("pthread_mutex_lock");
- clean_child_exit(APEXIT_CHILDFATAL);
- }
- have_accept_mutex = 1;
-}
-
-static void accept_mutex_off(void)
-{
- int err;
-
- if ((err = pthread_mutex_unlock(accept_mutex))) {
- errno = err;
- perror("pthread_mutex_unlock");
- clean_child_exit(APEXIT_CHILDFATAL);
- }
- /* There is a slight race condition right here... if we were to die right
- * now, we'd do another pthread_mutex_unlock. Now, doing that would let
- * another process into the mutex. pthread mutexes are designed to be
- * fast, as such they don't have protection for things like testing if the
- * thread owning a mutex is actually unlocking it (or even any way of
- * testing who owns the mutex).
- *
- * If we were to unset have_accept_mutex prior to releasing the mutex
- * then the race could result in the server unable to serve hits. Doing
- * it this way means that the server can continue, but an additional
- * child might be in the critical section ... at least it's still serving
- * hits.
- */
- have_accept_mutex = 0;
- if (sigprocmask(SIG_SETMASK, &accept_previous_mask, NULL)) {
- perror("sigprocmask(SIG_SETMASK)");
- clean_child_exit(1);
- }
-}
-
-#elif defined (USE_SYSVSEM_SERIALIZED_ACCEPT)
-
-#include <sys/types.h>
-#include <sys/ipc.h>
-#include <sys/sem.h>
-
-#ifdef NEED_UNION_SEMUN
-/* it makes no sense, but this isn't defined on solaris */
-union semun {
- long val;
- struct semid_ds *buf;
- ushort *array;
-};
-
-#endif
-
-static int sem_id = -1;
-static struct sembuf op_on;
-static struct sembuf op_off;
-
-/* We get a random semaphore ... the lame sysv semaphore interface
- * means we have to be sure to clean this up or else we'll leak
- * semaphores.
- */
-static void accept_mutex_cleanup(void *foo)
-{
- union semun ick;
-
- if (sem_id < 0)
- return;
- /* this is ignored anyhow */
- ick.val = 0;
- semctl(sem_id, 0, IPC_RMID, ick);
-}
-
-#define accept_mutex_child_init(x)
-
-static void accept_mutex_init(ap_pool_t *p)
-{
- union semun ick;
- struct semid_ds buf;
-
- /* acquire the semaphore */
- sem_id = semget(IPC_PRIVATE, 1, IPC_CREAT | 0600);
- if (sem_id < 0) {
- perror("semget");
- exit(APEXIT_INIT);
- }
- ick.val = 1;
- if (semctl(sem_id, 0, SETVAL, ick) < 0) {
- perror("semctl(SETVAL)");
- exit(APEXIT_INIT);
- }
- if (!getuid()) {
- /* restrict it to use only by the appropriate user_id ... not that this
- * stops CGIs from acquiring it and dinking around with it.
- */
- buf.sem_perm.uid = unixd_config.user_id;
- buf.sem_perm.gid = unixd_config.group_id;
- buf.sem_perm.mode = 0600;
- ick.buf = &buf;
- if (semctl(sem_id, 0, IPC_SET, ick) < 0) {
- perror("semctl(IPC_SET)");
- exit(APEXIT_INIT);
- }
- }
- ap_register_cleanup(p, NULL, accept_mutex_cleanup, ap_null_cleanup);
-
- /* preinitialize these */
- op_on.sem_num = 0;
- op_on.sem_op = -1;
- op_on.sem_flg = SEM_UNDO;
- op_off.sem_num = 0;
- op_off.sem_op = 1;
- op_off.sem_flg = SEM_UNDO;
-}
-
-static void accept_mutex_on(void)
-{
- while (semop(sem_id, &op_on, 1) < 0) {
- if (errno != EINTR) {
- perror("accept_mutex_on");
- clean_child_exit(APEXIT_CHILDFATAL);
- }
- }
-}
-
-static void accept_mutex_off(void)
-{
- while (semop(sem_id, &op_off, 1) < 0) {
- if (errno != EINTR) {
- perror("accept_mutex_off");
- clean_child_exit(APEXIT_CHILDFATAL);
- }
- }
-}
-
-#elif defined(USE_FCNTL_SERIALIZED_ACCEPT)
-static struct flock lock_it;
-static struct flock unlock_it;
-
-static int lock_fd = -1;
-
-#define accept_mutex_child_init(x)
-
-/*
- * Initialize mutex lock.
- * Must be safe to call this on a restart.
- */
-static void accept_mutex_init(ap_pool_t *p)
-{
- ap_file_t *tempfile = NULL;
- 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 */
-
- expand_lock_fname(p);
- ap_open(&tempfile, ap_lock_fname, APR_CREATE | APR_WRITE | APR_EXCL,
- APR_UREAD | APR_UWRITE | APR_GREAD | APR_WREAD, p);
- ap_get_os_file(&lock_fd, tempfile);
- if (lock_fd == -1) {
- perror("open");
- ap_log_error(APLOG_MARK, APLOG_STARTUP | APLOG_NOERRNO, 0, NULL,
- "Cannot open lock file: %s", ap_lock_fname);
- exit(APEXIT_INIT);
- }
- unlink(ap_lock_fname);
-}
-
-static void accept_mutex_on(void)
-{
- int ret;
-
- while ((ret = fcntl(lock_fd, F_SETLKW, &lock_it)) < 0 && errno == EINTR) {
- /* nop */
- }
-
- if (ret < 0) {
- ap_log_error(APLOG_MARK, APLOG_EMERG, errno, ap_server_conf,
- "fcntl: F_SETLKW: Error getting accept lock, exiting! "
- "Perhaps you need to use the LockFile directive to place "
- "your lock file on a local disk!");
- clean_child_exit(APEXIT_CHILDFATAL);
- }
-}
-
-static void accept_mutex_off(void)
-{
- int ret;
- while ((ret = fcntl(lock_fd, F_SETLKW, &unlock_it)) < 0 && errno == EINTR) {
- /* nop */
- }
- if (ret < 0) {
- ap_log_error(APLOG_MARK, APLOG_EMERG, errno, ap_server_conf,
- "fcntl: F_SETLKW: Error freeing accept lock, exiting! "
- "Perhaps you need to use the LockFile directive to place "
- "your lock file on a local disk!");
- clean_child_exit(APEXIT_CHILDFATAL);
- }
-}
-
-#elif defined(USE_FLOCK_SERIALIZED_ACCEPT)
-
-static int lock_fd = -1;
-
-static ap_status_t accept_mutex_cleanup(void *foo)
-{
- unlink(ap_lock_fname);
-
- return APR_SUCCESS;
-}
-
-/*
- * Initialize mutex lock.
- * Done by each child at it's birth
+/* Initialize mutex lock.
+ * Done by each child at its birth
*/
static void accept_mutex_child_init(ap_pool_t *p)
{
- ap_file_t *tempfile = NULL;
- ap_status_t ret;
-
- ret=ap_open(&tempfile, ap_lock_fname, APR_WRITE, APR_UREAD|APR_UWRITE, p);
- if (ret != APR_SUCCESS) {
- ap_log_error(APLOG_MARK, APLOG_EMERG, ret, ap_server_conf,
- "Child cannot open lock file: %s", ap_lock_fname);
- clean_child_exit(APEXIT_CHILDINIT);
- }
- ap_get_os_file(&lock_fd, tempfile);
+ ap_child_init_lock(&accept_lock, ap_lock_fname, p);
}
-/*
- * Initialize mutex lock.
+/* Initialize mutex lock.
* Must be safe to call this on a restart.
*/
static void accept_mutex_init(ap_pool_t *p)
{
- ap_file_t *tempfile = NULL;
- ap_status_t ret;
+ ap_status_t rv;
expand_lock_fname(p);
- unlink(ap_lock_fname);
- ret=ap_open(&tempfile, ap_lock_fname, APR_CREATE|APR_WRITE|APR_EXCL,
- APR_UREAD|APR_UWRITE, p);
- if (ret != APR_SUCCESS) {
- ap_log_error(APLOG_MARK, APLOG_EMERG, ret, ap_server_conf,
- "Parent cannot open lock file: %s", ap_lock_fname);
- exit(APEXIT_INIT);
- }
- ap_get_os_file(&lock_fd, tempfile);
- ap_register_cleanup(p, NULL, accept_mutex_cleanup, ap_null_cleanup);
-}
-
-static void accept_mutex_on(void)
-{
- int ret;
-
- while ((ret = flock(lock_fd, LOCK_EX)) < 0 && errno == EINTR)
- continue;
-
- if (ret < 0) {
- ap_log_error(APLOG_MARK, APLOG_EMERG, errno, ap_ap_server_conf,
- "flock: LOCK_EX: Error getting accept lock. Exiting!");
- clean_child_exit(APEXIT_CHILDFATAL);
- }
-}
-
-static void accept_mutex_off(void)
-{
- if (flock(lock_fd, LOCK_UN) < 0) {
- ap_log_error(APLOG_MARK, APLOG_EMERG, errno, ap_server_conf,
- "flock: LOCK_UN: Error freeing accept lock. Exiting!");
- clean_child_exit(APEXIT_CHILDFATAL);
- }
-}
-
-#elif defined(USE_OS2SEM_SERIALIZED_ACCEPT)
-
-static HMTX lock_sem = -1;
-
-static void accept_mutex_cleanup(void *foo)
-{
- DosReleaseMutexSem(lock_sem);
- DosCloseMutexSem(lock_sem);
-}
-
-/*
- * Initialize mutex lock.
- * Done by each child at it's birth
- */
-static void accept_mutex_child_init(ap_pool_t *p)
-{
- int rc = DosOpenMutexSem(NULL, &lock_sem);
-
- if (rc != 0) {
- ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_EMERG, ap_server_conf,
- "Child cannot open lock semaphore, rc=%d", rc);
- clean_child_exit(APEXIT_CHILDINIT);
- } else {
- ap_register_cleanup(p, NULL, accept_mutex_cleanup, ap_null_cleanup);
- }
-}
-
-/*
- * Initialize mutex lock.
- * Must be safe to call this on a restart.
- */
-static void accept_mutex_init(ap_pool_t *p)
-{
- int rc = DosCreateMutexSem(NULL, &lock_sem, DC_SEM_SHARED, FALSE);
-
- if (rc != 0) {
- ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_EMERG, ap_server_conf,
- "Parent cannot create lock semaphore, rc=%d", rc);
- exit(APEXIT_INIT);
- }
-
- ap_register_cleanup(p, NULL, accept_mutex_cleanup, ap_null_cleanup);
-}
-
-static void accept_mutex_on(void)
-{
- int rc = DosRequestMutexSem(lock_sem, SEM_INDEFINITE_WAIT);
-
- if (rc != 0) {
- ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_EMERG, ap_server_conf,
- "OS2SEM: Error %d getting accept lock. Exiting!", rc);
- clean_child_exit(APEXIT_CHILDFATAL);
+ rv = ap_create_lock(&accept_lock, APR_MUTEX, APR_CROSS_PROCESS, ap_lock_fname, p);
+ if (rv) {
+ ap_log_error(APLOG_MARK, APLOG_ERR, rv, NULL, "couldn't create accept mutex");
}
}
-static void accept_mutex_off(void)
-{
- int rc = DosReleaseMutexSem(lock_sem);
-
- if (rc != 0) {
- ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_EMERG, ap_server_conf,
- "OS2SEM: Error %d freeing accept lock. Exiting!", rc);
- clean_child_exit(APEXIT_CHILDFATAL);
- }
-}
-
-#elif defined(USE_TPF_CORE_SERIALIZED_ACCEPT)
-
-static int tpf_core_held;
-
-static void accept_mutex_cleanup(void *foo)
-{
- if(tpf_core_held)
- coruc(RESOURCE_KEY);
-}
-
-#define accept_mutex_init(x)
-
-static void accept_mutex_child_init(ap_pool_t *p)
-{
- ap_register_cleanup(p, NULL, accept_mutex_cleanup, ap_null_cleanup);
- tpf_core_held = 0;
-}
-
static void accept_mutex_on(void)
{
- corhc(RESOURCE_KEY);
- tpf_core_held = 1;
- ap_check_signals();
+ ap_status_t rv = ap_lock(accept_lock);
+ ap_assert(!rv);
}
static void accept_mutex_off(void)
{
- coruc(RESOURCE_KEY);
- tpf_core_held = 0;
- ap_check_signals();
+ ap_status_t rv = ap_unlock(accept_lock);
+ ap_assert(!rv);
}
-
-#else
-/* Default --- no serialization. Other methods *could* go here,
- * as #elifs...
- */
-#if !defined(MULTITHREAD)
-/* Multithreaded systems don't complete between processes for
- * the sockets. */
-#define NO_SERIALIZED_ACCEPT
-#define accept_mutex_child_init(x)
-#define accept_mutex_init(x)
-#define accept_mutex_on()
-#define accept_mutex_off()
-#endif
-#endif
/* On some architectures it's safe to do unserialized accept()s in the single
* Listen case. But it's never safe to do it in the case where there's
Re: cvs commit: apache-2.0/src/modules/mpm/prefork prefork.c
Posted by Greg Ames <gr...@raleigh.ibm.com>.
Rodent of Unusual Size wrote:
>
> Which picture was this?
http://www.apache.org/~fanf/fight.jpg
nyuk, nyuk, nyuk!
Greg
Re: cvs commit: apache-2.0/src/modules/mpm/prefork prefork.c
Posted by Rodent of Unusual Size <Ke...@Golux.Com>.
Jeff Trawick wrote:
>
> By the way... Dirk's picture was great. I need to put copies of it
> next to all my computers just to keep things in perspective :)
Which picture was this?
--
#ken P-)}
Ken Coar <http://Golux.Com/coar/>
Apache Software Foundation <http://www.apache.org/>
"Apache Server for Dummies" <http://Apache-Server.Com/>
"Apache Server Unleashed" <http://ApacheUnleashed.Com/>
Re: cvs commit: apache-2.0/src/modules/mpm/prefork prefork.c
Posted by rb...@covalent.net.
> > Does that mean that the most efficient lock is no lock at all? That
isn't
> > up to APR to implement. APR implements a locking scheme, it is up to the
> > application/platform to decide if that scheme is a good choice or
> > not.
>
> No, I meant something else:
>
> There is no APR equivalent of what used to be inside
> USE_USLOCK_SERIALIZED_ACCEPT and USE_TPF_CORE_SERIALIZED_ACCEPT in
> prefork.c. This was code to make a system-specific syscall to use a
> system-specific type of mutex. I just meant that SGI and TPF folks
> could add code to APR to map APR locks onto those primitives. Until
> that time, SGI and TPF must use fcntl, flock, sysvsem, or whatever
> else APR currently implements.
Ahhhh. This makes sense to me now. Thank you for the clarification.
Ryan
_______________________________________________________________________________
Ryan Bloom rbb@apache.org
406 29th St.
San Francisco, CA 94131
-------------------------------------------------------------------------------
Re: cvs commit: apache-2.0/src/modules/mpm/prefork prefork.c
Posted by Jeff Trawick <tr...@bellsouth.net>.
> From: rbb@covalent.net
> Date: Fri, 9 Jun 2000 08:24:16 -0700 (PDT)
>
>
> > > > Note: The TPF and SGI folks need to each APR how to get the most
> > > > efficient lock on those platforms. (For SGI it depends on whether
> > > > or not we're building for SMP.)
> >
> > Telling APR which lock to use via hints.m4 is something somebody needs
> > to implement before long, but the TPF and SGI issue I meant to allude
> > to here is that APR has no implementation of the most efficient locks
> > on those platforms. prefork did, but not after this commit. I won't
> > lose any sleep over it (TPF and SGI can if they so choose), but I
> > thought I would mention it.
>
> Does that mean that the most efficient lock is no lock at all? That isn't
> up to APR to implement. APR implements a locking scheme, it is up to the
> application/platform to decide if that scheme is a good choice or
> not.
No, I meant something else:
There is no APR equivalent of what used to be inside
USE_USLOCK_SERIALIZED_ACCEPT and USE_TPF_CORE_SERIALIZED_ACCEPT in
prefork.c. This was code to make a system-specific syscall to use a
system-specific type of mutex. I just meant that SGI and TPF folks
could add code to APR to map APR locks onto those primitives. Until
that time, SGI and TPF must use fcntl, flock, sysvsem, or whatever
else APR currently implements.
--
Jeff Trawick | trawick@ibm.net | PGP public key at web site:
http://www.geocities.com/SiliconValley/Park/9289/
Born in Roswell... married an alien...
Re: cvs commit: apache-2.0/src/modules/mpm/prefork prefork.c
Posted by rb...@covalent.net.
> > > Note: The TPF and SGI folks need to each APR how to get the most
> > > efficient lock on those platforms. (For SGI it depends on whether
> > > or not we're building for SMP.)
>
> Telling APR which lock to use via hints.m4 is something somebody needs
> to implement before long, but the TPF and SGI issue I meant to allude
> to here is that APR has no implementation of the most efficient locks
> on those platforms. prefork did, but not after this commit. I won't
> lose any sleep over it (TPF and SGI can if they so choose), but I
> thought I would mention it.
Does that mean that the most efficient lock is no lock at all? That isn't
up to APR to implement. APR implements a locking scheme, it is up to the
application/platform to decide if that scheme is a good choice or not.
>
> By the way... Dirk's picture was great. I need to put copies of it
> next to all my computers just to keep things in perspective :)
Yeah, we had a good time with it. :-)
Ryan
_______________________________________________________________________________
Ryan Bloom rbb@apache.org
406 29th St.
San Francisco, CA 94131
-------------------------------------------------------------------------------
Re: cvs commit: apache-2.0/src/modules/mpm/prefork prefork.c
Posted by Jeff Trawick <tr...@bellsouth.net>.
> Date: Fri, 9 Jun 2000 11:31:57 -0400 (EDT)
> From: David Williams <dw...@cisco.com>
>
> On Fri, 9 Jun 2000, Jeff Trawick wrote:
>
> > Telling APR which lock to use via hints.m4 is something somebody needs
> > to implement before long, but the TPF and SGI issue I meant to allude
> > to here is that APR has no implementation of the most efficient locks
> > on those platforms. prefork did, but not after this commit. I won't
> > lose any sleep over it (TPF and SGI can if they so choose), but I
> > thought I would mention it.
>
> Is that something that could be added to mpm/prefork/config.m4? Or is
> there no way for configure to easily check the platform by a "uname"
> type call. For alpha 3, I needed to add this to config.m4:
> AC_DEFINE(USE_FCNTL_SERIALIZED_ACCEPT,,
> [Define this if File Control serialization will be used.])
> for the accept_mutex_on() to work properly on unix.
>
> thanks,
> -david
You shouldn't need anything like that in config.m4 anymore (well, once
you get the current level of code).
prefork.c is now fixed so that it will always get an accept mutex for
the multiple listen case and unless SINGLE_LISTEN_NO_SERIALIZED_ACCEPT
is defined it will get an accept mutex for the single listen case.
prefork.c no longer decides which syscalls to use for the accept
mutex; that is deferred to APR.
If you want to tell APR to use SysV sems instead of fcntl() locks
(just an example): there is no clean way to do that yet...
Eventually there will be stuff in hints.m4 to choose the best known
mutex primitive for various platforms.
Currently you can play tricks in src/lib/apr/locks/unix/lock.h after
apr_private.h is included and before any #ifdef APR_USE_xyz_SERIALIZE,
but I wouldn't recommend that for general use :)
--
Jeff Trawick | trawick@ibm.net | PGP public key at web site:
http://www.geocities.com/SiliconValley/Park/9289/
Born in Roswell... married an alien...
Re: cvs commit: apache-2.0/src/modules/mpm/prefork prefork.c
Posted by Jeff Trawick <tr...@bellsouth.net>.
> From: rbb@covalent.net
> Date: Fri, 9 Jun 2000 08:35:39 -0700 (PDT)
> This is what I thought Jeff meant at first. In order to fix this problem,
> we need to do two things:
>
> 1) Add the ability to specify locking mechanism on the APR ./configure
> command line
>
> 2) For platforms that have specific locking needs, add that to the
> hints.m4 file.
>
> Step 1 will take a matter of hours once somebody decides to do it. Step 2
> should take minutes for the platforms we have information for from
> 1.3.
Not really what I meant, but I agree 100% that it is needed :) I
didn't think of the ./configure command line possibility... that will
be nice.
--
Jeff Trawick | trawick@ibm.net | PGP public key at web site:
http://www.geocities.com/SiliconValley/Park/9289/
Born in Roswell... married an alien...
Re: cvs commit: apache-2.0/src/modules/mpm/prefork prefork.c
Posted by rb...@covalent.net.
> > Telling APR which lock to use via hints.m4 is something somebody needs
> > to implement before long, but the TPF and SGI issue I meant to allude
> > to here is that APR has no implementation of the most efficient locks
> > on those platforms. prefork did, but not after this commit. I won't
> > lose any sleep over it (TPF and SGI can if they so choose), but I
> > thought I would mention it.
>
> Is that something that could be added to mpm/prefork/config.m4? Or is
> there no way for configure to easily check the platform by a "uname"
> type call. For alpha 3, I needed to add this to config.m4:
> AC_DEFINE(USE_FCNTL_SERIALIZED_ACCEPT,,
> [Define this if File Control serialization will be used.])
> for the accept_mutex_on() to work properly on unix.
This is what I thought Jeff meant at first. In order to fix this problem,
we need to do two things:
1) Add the ability to specify locking mechanism on the APR ./configure
command line
2) For platforms that have specific locking needs, add that to the
hints.m4 file.
Step 1 will take a matter of hours once somebody decides to do it. Step 2
should take minutes for the platforms we have information for from 1.3.
Ryan
_______________________________________________________________________________
Ryan Bloom rbb@apache.org
406 29th St.
San Francisco, CA 94131
-------------------------------------------------------------------------------
Re: cvs commit: apache-2.0/src/modules/mpm/prefork prefork.c
Posted by David Williams <dw...@cisco.com>.
On Fri, 9 Jun 2000, Jeff Trawick wrote:
> > From: rbb@covalent.net
> > Date: Fri, 9 Jun 2000 07:57:47 -0700 (PDT)
> >
> >
> > > Note: The TPF and SGI folks need to each APR how to get the most
> > > efficient lock on those platforms. (For SGI it depends on whether
> > > or not we're building for SMP.)
> >
> > I assume your asking here how to tell APR which lock to use. I don't
> > think you can, yet. This is something that needs to be done soon. Then,
> > the hints file can pass this information around.
> >
> > Ryan
>
> I wasn't very clear, and the typo didn't help :(
>
> Telling APR which lock to use via hints.m4 is something somebody needs
> to implement before long, but the TPF and SGI issue I meant to allude
> to here is that APR has no implementation of the most efficient locks
> on those platforms. prefork did, but not after this commit. I won't
> lose any sleep over it (TPF and SGI can if they so choose), but I
> thought I would mention it.
Is that something that could be added to mpm/prefork/config.m4? Or is
there no way for configure to easily check the platform by a "uname"
type call. For alpha 3, I needed to add this to config.m4:
AC_DEFINE(USE_FCNTL_SERIALIZED_ACCEPT,,
[Define this if File Control serialization will be used.])
for the accept_mutex_on() to work properly on unix.
thanks,
-david
Re: cvs commit: apache-2.0/src/modules/mpm/prefork prefork.c
Posted by Jeff Trawick <tr...@bellsouth.net>.
> From: rbb@covalent.net
> Date: Fri, 9 Jun 2000 07:57:47 -0700 (PDT)
>
>
> > Note: The TPF and SGI folks need to each APR how to get the most
> > efficient lock on those platforms. (For SGI it depends on whether
> > or not we're building for SMP.)
>
> I assume your asking here how to tell APR which lock to use. I don't
> think you can, yet. This is something that needs to be done soon. Then,
> the hints file can pass this information around.
>
> Ryan
I wasn't very clear, and the typo didn't help :(
Telling APR which lock to use via hints.m4 is something somebody needs
to implement before long, but the TPF and SGI issue I meant to allude
to here is that APR has no implementation of the most efficient locks
on those platforms. prefork did, but not after this commit. I won't
lose any sleep over it (TPF and SGI can if they so choose), but I
thought I would mention it.
By the way... Dirk's picture was great. I need to put copies of it
next to all my computers just to keep things in perspective :)
--
Jeff Trawick | trawick@ibm.net | PGP public key at web site:
http://www.geocities.com/SiliconValley/Park/9289/
Born in Roswell... married an alien...
Re: cvs commit: apache-2.0/src/modules/mpm/prefork prefork.c
Posted by rb...@covalent.net.
> Note: The TPF and SGI folks need to each APR how to get the most
> efficient lock on those platforms. (For SGI it depends on whether
> or not we're building for SMP.)
I assume your asking here how to tell APR which lock to use. I don't
think you can, yet. This is something that needs to be done soon. Then,
the hints file can pass this information around.
Ryan
_______________________________________________________________________________
Ryan Bloom rbb@apache.org
406 29th St.
San Francisco, CA 94131
-------------------------------------------------------------------------------
Re: cvs commit: apache-2.0/src/modules/mpm/prefork prefork.c
Posted by rb...@covalent.net.
> Note: The TPF and SGI folks need to each APR how to get the most
> efficient lock on those platforms. (For SGI it depends on whether
> or not we're building for SMP.)
I assume your asking here how to tell APR which lock to use. I don't
think you can, yet. This is something that needs to be done soon. Then,
the hints file can pass this information around.
Ryan
_______________________________________________________________________________
Ryan Bloom rbb@apache.org
406 29th St.
San Francisco, CA 94131
-------------------------------------------------------------------------------