d/freebsd-dev
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity
b025fc9a31
freebsd-dev/lib/libpthread/thread/thr_read.c

56 lines
2.1 KiB
C
Raw Normal View History

Reviewed by: julian Submitted by: john birrel One version of the pthreads library another will follow with differnt actions under some cases.. not QUITE complete
1996-01-22 00:23:58 +00:00
/*
Change signal model to match POSIX (i.e. one set of signal handlers for the process, not a separate set for each thread). By default, the process now only has signal handlers installed for SIGVTALRM, SIGINFO and SIGCHLD. The thread kernel signal handler is installed for other signals on demand. This means that SIG_IGN and SIG_DFL processing is now left to the kernel, not the thread kernel. Change the signal dispatch to no longer use a signal thread, and call the signal handler using the stack of the thread that has the signal pending. Change the atomic lock method to use test-and-set asm code with a yield if blocked. This introduces separate locks for each type of object instead of blocking signals to prevent a context switch. It was this blocking of signals that caused the performance degradation the people have noted. This is a *big* change!
1998-04-29 09:59:34 +00:00
* Copyright (c) 1995-1998 John Birrell <jb@cimlogic.com.au>
Reviewed by: julian Submitted by: john birrel One version of the pthreads library another will follow with differnt actions under some cases.. not QUITE complete
1996-01-22 00:23:58 +00:00
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by John Birrell.
* 4. Neither the name of the author nor the names of any co-contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
Add RCS IDs to those files without them. Fix copyrights (s/REGENTS/AUTHOR). Suggested by: tg Approved by: jb
1999-08-05 12:15:30 +00:00
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
Reviewed by: julian Submitted by: john birrel One version of the pthreads library another will follow with differnt actions under some cases.. not QUITE complete
1996-01-22 00:23:58 +00:00
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
$Id$ -> $FreeBSD$
1999-08-28 00:22:10 +00:00
* $FreeBSD$
Add parentheses to make blocking mode work.
1997-04-01 22:44:18 +00:00
*
Reviewed by: julian Submitted by: john birrel One version of the pthreads library another will follow with differnt actions under some cases.. not QUITE complete
1996-01-22 00:23:58 +00:00
*/
#include <sys/types.h>
#include <sys/fcntl.h>
#include <sys/uio.h>
#include <errno.h>
#include <unistd.h>
#include <pthread.h>
Make the changes needed for libpthread to compile in its new home. The new libpthread will provide POSIX threading support using KSE. These files were previously repo-copied from src/lib/libc_r. Reviewed by: deischen Approved by: -arch
2002-09-16 08:45:36 +00:00
#include "thr_private.h"
Reviewed by: julian Submitted by: john birrel One version of the pthreads library another will follow with differnt actions under some cases.. not QUITE complete
1996-01-22 00:23:58 +00:00
To be consistent, use the __weak_reference macro from <sys/cdefs.h> instead of #pragma weak to create weak definitions. Suggested by: bde
2001-04-10 04:19:21 +00:00
__weak_reference(__read, read);
Add weak definitions for wrapped system calls. In general: _foo - wrapped system call foo - weak definition to _foo and for cancellation points: _foo - wrapped system call __foo - enter cancellation point, call _foo(), leave cancellation point foo - weak definition to __foo Change use of global _thread_run to call a function to get the currently running thread. Make all pthread_foo functions weak definitions to _pthread_foo, where _pthread_foo is the implementation. This allows an application to provide its own pthread functions. Provide slightly different versions of pthread_mutex_lock and pthread_mutex_init so that we can tell the difference between a libc mutex and an application mutex. Threads holding mutexes internal to libc should never be allowed to exit, call signal handlers, or cancel. Approved by: -arch
2001-01-24 13:03:38 +00:00
Simplify sytem call renaming. Instead of _foo() <-- _libc_foo <-- foo(), just use _foo() <-- foo(). In the case of a libpthread that doesn't do call conversion (such as linuxthreads and our upcoming libpthread), this is adequate. In the case of libc_r, we still need three names, which are now _thread_sys_foo() <-- _foo() <-- foo(). Convert all internal libc usage of: aio_suspend(), close(), fsync(), msync(), nanosleep(), open(), fcntl(), read(), and write() to _foo() instead of foo(). Remove all internal libc usage of: creat(), pause(), sleep(), system(), tcdrain(), wait(), and waitpid(). Make thread cancellation fully POSIX-compliant. Suggested by: deischen
2000-01-27 23:07:25 +00:00
ssize_t
Add weak definitions for wrapped system calls. In general: _foo - wrapped system call foo - weak definition to _foo and for cancellation points: _foo - wrapped system call __foo - enter cancellation point, call _foo(), leave cancellation point foo - weak definition to __foo Change use of global _thread_run to call a function to get the currently running thread. Make all pthread_foo functions weak definitions to _pthread_foo, where _pthread_foo is the implementation. This allows an application to provide its own pthread functions. Provide slightly different versions of pthread_mutex_lock and pthread_mutex_init so that we can tell the difference between a libc mutex and an application mutex. Threads holding mutexes internal to libc should never be allowed to exit, call signal handlers, or cancel. Approved by: -arch
2001-01-24 13:03:38 +00:00
__read(int fd, void *buf, size_t nbytes)
Simplify sytem call renaming. Instead of _foo() <-- _libc_foo <-- foo(), just use _foo() <-- foo(). In the case of a libpthread that doesn't do call conversion (such as linuxthreads and our upcoming libpthread), this is adequate. In the case of libc_r, we still need three names, which are now _thread_sys_foo() <-- _foo() <-- foo(). Convert all internal libc usage of: aio_suspend(), close(), fsync(), msync(), nanosleep(), open(), fcntl(), read(), and write() to _foo() instead of foo(). Remove all internal libc usage of: creat(), pause(), sleep(), system(), tcdrain(), wait(), and waitpid(). Make thread cancellation fully POSIX-compliant. Suggested by: deischen
2000-01-27 23:07:25 +00:00
{
ssize_t ret;
_thread_enter_cancellation_point();
Make libpthread KSE aware. Reviewed by: deischen, julian Approved by: -arch
2002-09-16 19:52:52 +00:00
ret = __sys_read(fd, buf, nbytes);
Simplify sytem call renaming. Instead of _foo() <-- _libc_foo <-- foo(), just use _foo() <-- foo(). In the case of a libpthread that doesn't do call conversion (such as linuxthreads and our upcoming libpthread), this is adequate. In the case of libc_r, we still need three names, which are now _thread_sys_foo() <-- _foo() <-- foo(). Convert all internal libc usage of: aio_suspend(), close(), fsync(), msync(), nanosleep(), open(), fcntl(), read(), and write() to _foo() instead of foo(). Remove all internal libc usage of: creat(), pause(), sleep(), system(), tcdrain(), wait(), and waitpid(). Make thread cancellation fully POSIX-compliant. Suggested by: deischen
2000-01-27 23:07:25 +00:00
_thread_leave_cancellation_point();
return ret;
}
Reference in New Issue Copy Permalink