From cba0ca7925f8e324e8af9f88187b3473363853a1 Mon Sep 17 00:00:00 2001 From: Ulrich Drepper Date: Sat, 16 May 2009 14:55:59 -0700 Subject: Unify source for async cancel handling. Unify all three places where we enable async cancellation for syscalls. Optimize a bit. --- nptl/ChangeLog | 5 ++ nptl/cancellation.c | 3 - nptl/libc-cancellation.c | 102 +----------------------------- nptl/sysdeps/pthread/librt-cancellation.c | 91 ++------------------------ 4 files changed, 12 insertions(+), 189 deletions(-) (limited to 'nptl') diff --git a/nptl/ChangeLog b/nptl/ChangeLog index b83128e5af..23083611b4 100644 --- a/nptl/ChangeLog +++ b/nptl/ChangeLog @@ -1,5 +1,10 @@ 2009-05-16 Ulrich Drepper + * cancellation.c (__pthread_disable_asynccancel): Remove unnecessary + test. + * libc-cancellation.c: Use -#include #include "pthreadP.h" -#include -#include -#ifndef NOT_IN_libc - -/* The next two functions are similar to pthread_setcanceltype() but - more specialized for the use in the cancelable functions like write(). - They do not need to check parameters etc. */ -int -attribute_hidden -__libc_enable_asynccancel (void) -{ - struct pthread *self = THREAD_SELF; - int oldval = THREAD_GETMEM (self, cancelhandling); - - while (1) - { - int newval = oldval | CANCELTYPE_BITMASK; - - if (__builtin_expect ((oldval & CANCELED_BITMASK) != 0, 0)) - { - /* If we are already exiting or if PTHREAD_CANCEL_DISABLED, - stop right here. */ - if ((oldval & (EXITING_BITMASK | CANCELSTATE_BITMASK)) != 0) - break; - - int curval = THREAD_ATOMIC_CMPXCHG_VAL (self, cancelhandling, - newval, oldval); - if (__builtin_expect (curval != oldval, 0)) - { - /* Somebody else modified the word, try again. */ - oldval = curval; - continue; - } - - THREAD_SETMEM (self, result, PTHREAD_CANCELED); - - __do_cancel (); - - /* NOTREACHED */ - } - - int curval = THREAD_ATOMIC_CMPXCHG_VAL (self, cancelhandling, newval, - oldval); - if (__builtin_expect (curval == oldval, 1)) - break; - - /* Prepare the next round. */ - oldval = curval; - } - - return oldval; -} - - -void -internal_function attribute_hidden -__libc_disable_asynccancel (int oldtype) -{ - /* If asynchronous cancellation was enabled before we do not have - anything to do. */ - if (oldtype & CANCELTYPE_BITMASK) - return; - - struct pthread *self = THREAD_SELF; - int newval; - - int oldval = THREAD_GETMEM (self, cancelhandling); - - while (1) - { - newval = oldval & ~CANCELTYPE_BITMASK; - - if (newval == oldval) - break; - - int curval = THREAD_ATOMIC_CMPXCHG_VAL (self, cancelhandling, newval, - oldval); - if (__builtin_expect (curval == oldval, 1)) - break; - - /* Prepare the next round. */ - oldval = curval; - } - - /* We cannot return when we are being canceled. Upon return the - thread might be things which would have to be undone. The - following loop should loop until the cancellation signal is - delivered. */ - while (__builtin_expect ((newval & (CANCELING_BITMASK | CANCELED_BITMASK)) - == CANCELING_BITMASK, 0)) - { - lll_futex_wait (&self->cancelhandling, newval, LLL_PRIVATE); - newval = THREAD_GETMEM (self, cancelhandling); - } -} +#define __pthread_enable_asynccancel __libc_enable_asynccancel +#define __pthread_disable_asynccancel __libc_disable_asynccancel +#include void @@ -125,5 +31,3 @@ __libc_cleanup_routine (struct __pthread_cleanup_frame *f) if (f->__do_it) f->__cancel_routine (f->__cancel_arg); } - -#endif diff --git a/nptl/sysdeps/pthread/librt-cancellation.c b/nptl/sysdeps/pthread/librt-cancellation.c index 753a2d831e..d9f7ad9ea3 100644 --- a/nptl/sysdeps/pthread/librt-cancellation.c +++ b/nptl/sysdeps/pthread/librt-cancellation.c @@ -1,4 +1,4 @@ -/* Copyright (C) 2002, 2003 Free Software Foundation, Inc. +/* Copyright (C) 2002, 2003, 2009 Free Software Foundation, Inc. This file is part of the GNU C Library. Contributed by Ulrich Drepper , 2002. @@ -17,92 +17,9 @@ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. */ -#include -#include -#include #include "pthreadP.h" -#include "atomic.h" -#ifdef IS_IN_librt -/* The next two functions are similar to pthread_setcanceltype() but - more specialized for the use in the cancelable functions like write(). - They do not need to check parameters etc. */ -int -attribute_hidden -__librt_enable_asynccancel (void) -{ - struct pthread *self = THREAD_SELF; - int oldval = THREAD_GETMEM (self, cancelhandling); - - while (1) - { - int newval = oldval | CANCELTYPE_BITMASK; - - if (__builtin_expect ((oldval & CANCELED_BITMASK) != 0, 0)) - { - /* If we are already exiting or if PTHREAD_CANCEL_DISABLED, - stop right here. */ - if ((oldval & (EXITING_BITMASK | CANCELSTATE_BITMASK)) != 0) - break; - - int curval = THREAD_ATOMIC_CMPXCHG_VAL (self, cancelhandling, - newval, oldval); - if (__builtin_expect (curval != oldval, 0)) - { - /* Somebody else modified the word, try again. */ - oldval = curval; - continue; - } - - THREAD_SETMEM (self, result, PTHREAD_CANCELED); - - __do_cancel (); - - /* NOTREACHED */ - } - - int curval = THREAD_ATOMIC_CMPXCHG_VAL (self, cancelhandling, newval, - oldval); - if (__builtin_expect (curval == oldval, 1)) - break; - - /* Prepare the next round. */ - oldval = curval; - } - - return oldval; -} - - -void -internal_function attribute_hidden -__librt_disable_asynccancel (int oldtype) -{ - /* If asynchronous cancellation was enabled before we do not have - anything to do. */ - if (oldtype & CANCELTYPE_BITMASK) - return; - - struct pthread *self = THREAD_SELF; - int oldval = THREAD_GETMEM (self, cancelhandling); - - while (1) - { - int newval = oldval & ~CANCELTYPE_BITMASK; - - if (newval == oldval) - break; - - int curval = THREAD_ATOMIC_CMPXCHG_VAL (self, cancelhandling, newval, - oldval); - if (__builtin_expect (curval == oldval, 1)) - break; - - /* Prepare the next round. */ - oldval = curval; - } -} - - -#endif +#define __pthread_enable_asynccancel __librt_enable_asynccancel +#define __pthread_disable_asynccancel __librt_disable_asynccancel +#include -- cgit 1.4.1