From 14e7aeceff58b18f970126e1562b0dbf340e2d6c Mon Sep 17 00:00:00 2001 From: Ulrich Drepper Date: Thu, 12 Dec 2002 10:28:11 +0000 Subject: [PATCH] Update. 2002-12-12 Ulrich Drepper * sysdeps/unix/sysv/linux/fork-gen.c: Renamed to... * sysdeps/unix/sysv/linux/libc_pthread_init.c: ...this. Initialize __libc_locking_needed. * init.c (__pthread_initialize_minimal): Call __libc_pthread_init instead of __register_pthread_fork_handler. * sysdeps/pthread/bits/libc-lock.h: Declare __libc_locking_needed. * sysdeps/unix/sysv/linux/Makefile (sysdep_routimes): Replace fork-gen with libc_pthread_init. * sysdeps/unix/sysv/linux/Versions: Use __libc_pthread_init instead of __register_pthread_fork_handler. * sysdeps/unix/sysv/linux/fork.h: Declare __libc_pthread_init instead of __register_pthread_fork_handler. * sysdeps/unix/sysv/linux/i386/lowlevellock.h: Use __libc_locking_needed to determine whether lock prefix can be avoided. * sysdeps/unix/sysv/linux/i386/i486/libc-lowlevellock.S: Likewise. --- nptl/ChangeLog | 18 ++ nptl/init.c | 2 +- nptl/sysdeps/pthread/bits/libc-lock.h | 4 + nptl/sysdeps/unix/sysv/linux/Makefile | 2 +- nptl/sysdeps/unix/sysv/linux/Versions | 2 +- nptl/sysdeps/unix/sysv/linux/fork.h | 4 +- .../unix/sysv/linux/i386/i486/libc-lowlevellock.S | 185 ++++++++++++++++++++- nptl/sysdeps/unix/sysv/linux/i386/lowlevellock.h | 60 ++++++- .../sysv/linux/{fork-gen.c => libc_pthread_init.c} | 12 +- 9 files changed, 279 insertions(+), 10 deletions(-) rename nptl/sysdeps/unix/sysv/linux/{fork-gen.c => libc_pthread_init.c} (74%) diff --git a/nptl/ChangeLog b/nptl/ChangeLog index c2a0347..245fa94 100644 --- a/nptl/ChangeLog +++ b/nptl/ChangeLog @@ -1,3 +1,21 @@ +2002-12-12 Ulrich Drepper + + * sysdeps/unix/sysv/linux/fork-gen.c: Renamed to... + * sysdeps/unix/sysv/linux/libc_pthread_init.c: ...this. + Initialize __libc_locking_needed. + * init.c (__pthread_initialize_minimal): Call __libc_pthread_init + instead of __register_pthread_fork_handler. + * sysdeps/pthread/bits/libc-lock.h: Declare __libc_locking_needed. + * sysdeps/unix/sysv/linux/Makefile (sysdep_routimes): Replace + fork-gen with libc_pthread_init. + * sysdeps/unix/sysv/linux/Versions: Use __libc_pthread_init instead + of __register_pthread_fork_handler. + * sysdeps/unix/sysv/linux/fork.h: Declare __libc_pthread_init instead + of __register_pthread_fork_handler. + * sysdeps/unix/sysv/linux/i386/lowlevellock.h: Use + __libc_locking_needed to determine whether lock prefix can be avoided. + * sysdeps/unix/sysv/linux/i386/i486/libc-lowlevellock.S: Likewise. + 2002-12-11 Ulrich Drepper * Makefile (tests): Add tst-cleanup1. diff --git a/nptl/init.c b/nptl/init.c index 678c0a5..7686e8c 100644 --- a/nptl/init.c +++ b/nptl/init.c @@ -167,5 +167,5 @@ __pthread_initialize_minimal (void) __static_tls_size = roundup (__static_tls_size, __static_tls_align); /* Register the fork generation counter with the libc. */ - __register_pthread_fork_handler (&__fork_generation, __reclaim_stacks); + __libc_pthread_init (&__fork_generation, __reclaim_stacks); } diff --git a/nptl/sysdeps/pthread/bits/libc-lock.h b/nptl/sysdeps/pthread/bits/libc-lock.h index de2ec7b..e594ede 100644 --- a/nptl/sysdeps/pthread/bits/libc-lock.h +++ b/nptl/sysdeps/pthread/bits/libc-lock.h @@ -25,6 +25,10 @@ #include +/* Nonzero if locking is needed. */ +extern int __libc_locking_needed attribute_hidden; + + /* Fortunately Linux now has a mean to do locking which is realtime safe without the aid of the thread library. We also need no fancy options like error checking mutexes etc. We only need simple diff --git a/nptl/sysdeps/unix/sysv/linux/Makefile b/nptl/sysdeps/unix/sysv/linux/Makefile index 9a84534..c079a40 100644 --- a/nptl/sysdeps/unix/sysv/linux/Makefile +++ b/nptl/sysdeps/unix/sysv/linux/Makefile @@ -18,7 +18,7 @@ # 02111-1307 USA. */ ifeq ($(subdir),nptl) -sysdep_routines += register-atfork unregister-atfork fork-gen +sysdep_routines += register-atfork unregister-atfork libc_pthread_init libpthread-sysdep_routines += pt-fork endif diff --git a/nptl/sysdeps/unix/sysv/linux/Versions b/nptl/sysdeps/unix/sysv/linux/Versions index 117598c..8fea097 100644 --- a/nptl/sysdeps/unix/sysv/linux/Versions +++ b/nptl/sysdeps/unix/sysv/linux/Versions @@ -1,6 +1,6 @@ libc { GLIBC_PRIVATE { - __register_atfork; __register_pthread_fork_handler; + __register_atfork; __libc_pthread_init; __libc_current_sigrtmin_private; __libc_current_sigrtmax_private; __libc_allocate_rtsig_private; } diff --git a/nptl/sysdeps/unix/sysv/linux/fork.h b/nptl/sysdeps/unix/sysv/linux/fork.h index 85722a5..0bc283d 100644 --- a/nptl/sysdeps/unix/sysv/linux/fork.h +++ b/nptl/sysdeps/unix/sysv/linux/fork.h @@ -56,5 +56,5 @@ extern int __register_atfork (void (*__prepare) (void), void *dso_handle); /* Register the generation counter in the libpthread with the libc. */ -extern void __register_pthread_fork_handler (unsigned long int *__ptr, - void (*reclaim) (void)); +extern void __libc_pthread_int (unsigned long int *__ptr, + void (*reclaim) (void)); diff --git a/nptl/sysdeps/unix/sysv/linux/i386/i486/libc-lowlevellock.S b/nptl/sysdeps/unix/sysv/linux/i386/i486/libc-lowlevellock.S index 3ce1d6f..9a124ab 100644 --- a/nptl/sysdeps/unix/sysv/linux/i386/i486/libc-lowlevellock.S +++ b/nptl/sysdeps/unix/sysv/linux/i386/i486/libc-lowlevellock.S @@ -1 +1,184 @@ -#include "lowlevellock.S" +/* Copyright (C) 2002 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Ulrich Drepper , 2002. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library 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 + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +#include + + .text + +#define SYS_gettimeofday __NR_gettimeofday +#define SYS_futex 240 +#define FUTEX_WAIT 0 +#define FUTEX_WAKE 1 + +#define ETIMEDOUT 110 + + + .globl __lll_lock_wait + .type __lll_lock_wait,@function + .hidden __lll_lock_wait + .align 16 +__lll_lock_wait: + pushl %esi + pushl %ebx + pushl %edx + + movl %ecx, %ebx + xorl %esi, %esi /* No timeout. */ + xorl %ecx, %ecx /* movl $FUTEX_WAIT, %ecx */ +1: + leal -1(%eax), %edx /* account for the preceeded xadd. */ + movl $SYS_futex, %eax + int $0x80 + + orl $-1, %eax /* Load -1. */ +#ifndef UP + cmpl $0, __libc_locking_needed + je,pt 0f + lock +0: +#endif + xaddl %eax, (%ebx) + jne 1b + + movl $-1, (%ebx) + + popl %edx + popl %ebx + popl %esi + ret + .size __lll_lock_wait,.-__lll_lock_wait + + + .globl lll_unlock_wake_cb + .type lll_unlock_wake_cb,@function + .hidden lll_unlock_wake_cb + .align 16 +lll_unlock_wake_cb: + pushl %esi + pushl %ebx + pushl %ecx + pushl %edx + + movl 20(%esp), %ebx +#ifndef UP + cmpl $0, __libc_locking_needed + je,pt 0f + lock +0: +#endif + incl (%ebx) + jng 1f + + popl %edx + popl %ecx + popl %ebx + popl %esi + ret + .size lll_unlock_wake_cb,.-lll_unlock_wake_cb + + + .globl __lll_unlock_wake + .type __lll_unlock_wake,@function + .hidden __lll_unlock_wake +__lll_unlock_wake: + pushl %esi + pushl %ebx + pushl %ecx + pushl %edx + + movl %eax, %ebx +1: movl $FUTEX_WAKE, %ecx + movl $1, %edx /* Wake one thread. */ + xorl %esi, %esi + movl %edx, (%ebx) /* Stores '$1'. */ + movl $SYS_futex, %eax + int $0x80 + + popl %edx + popl %ecx + popl %ebx + popl %esi + ret + .size __lll_unlock_wake,.-__lll_unlock_wake + + + .globl __lll_timedwait_tid + .type __lll_timedwait_tid,@function + .hidden __lll_timedwait_tid +__lll_timedwait_tid: + pushl %edi + pushl %esi + pushl %ebx + pushl %ebp + + movl %eax, %ebp + movl %edx, %edi + subl $8, %esp + + /* Get current time. */ +2: movl %esp, %ebx + xorl %ecx, %ecx + movl $SYS_gettimeofday, %eax + int $0x80 + + /* Compute relative timeout. */ + movl 4(%esp), %eax + movl $1000, %edx + mul %edx /* Milli seconds to nano seconds. */ + movl (%edi), %ecx + movl 4(%edi), %edx + subl (%esp), %ecx + subl %eax, %edx + jns 5f + addl $1000000000, %edx + decl %ecx +5: testl %ecx, %ecx + js 6f /* Time is already up. */ + + movl %ecx, (%esp) /* Store relative timeout. */ + movl %edx, 4(%esp) + + movl (%ebp), %edx + testl %edx, %edx + jz 4f + + movl %esp, %esi + xorl %ecx, %ecx /* movl $FUTEX_WAIT, %ecx */ + movl %ebp, %ebx + movl $SYS_futex, %eax + int $0x80 + + movl %eax, %edx + + cmpl $0, (%ebx) + jne 1f +4: xorl %eax, %eax + +3: addl $8, %esp + popl %ebp + popl %ebx + popl %esi + popl %edi + ret + +1: cmpl $-ETIMEDOUT, %edx + jne 2b +6: movl $ETIMEDOUT, %eax + jmp 3b + .size __lll_timedwait_tid,.-__lll_timedwait_tid diff --git a/nptl/sysdeps/unix/sysv/linux/i386/lowlevellock.h b/nptl/sysdeps/unix/sysv/linux/i386/lowlevellock.h index a3c0249..470dcf6 100644 --- a/nptl/sysdeps/unix/sysv/linux/i386/lowlevellock.h +++ b/nptl/sysdeps/unix/sysv/linux/i386/lowlevellock.h @@ -139,7 +139,8 @@ extern int lll_unlock_wake_cb (int *__futex) attribute_hidden; <0 - taken by more users */ -#define lll_trylock(futex) \ +#if defined NOT_IN_libc || defined UP +# define lll_trylock(futex) \ ({ unsigned char ret; \ __asm __volatile (LOCK_INSTR "cmpxchgl %2, %1; setne %0" \ : "=a" (ret), "=m" (futex) \ @@ -148,7 +149,7 @@ extern int lll_unlock_wake_cb (int *__futex) attribute_hidden; ret; }) -#define lll_lock(futex) \ +# define lll_lock(futex) \ (void) ({ int ignore1, ignore2; \ __asm __volatile (LOCK_INSTR "xaddl %0, %2\n\t" \ "jne 1f\n\t" \ @@ -163,7 +164,7 @@ extern int lll_unlock_wake_cb (int *__futex) attribute_hidden; : "memory"); }) -#define lll_unlock(futex) \ +# define lll_unlock(futex) \ (void) ({ int ignore; \ __asm __volatile (LOCK_INSTR "incl %0\n\t" \ "jng 1f\n\t" \ @@ -176,6 +177,59 @@ extern int lll_unlock_wake_cb (int *__futex) attribute_hidden; : "=m" (futex), "=&a" (ignore) \ : "0" (futex) \ : "memory"); }) +#else +/* Special versions of the macros for use in libc itself. They avoid + the lock prefix when the thread library is not used. + + XXX In future we might even want to avoid it on UP machines. */ + +# define lll_trylock(futex) \ + ({ unsigned char ret; \ + __asm __volatile ("cmpl $0, __libc_locking_needed\n\t" \ + "je,pt 0f\n\t" \ + "lock\n" \ + "0:\tcmpxchgl %2, %1; setne %0" \ + : "=a" (ret), "=m" (futex) \ + : "r" (0), "1" (futex), "0" (1) \ + : "memory"); \ + ret; }) + + +# define lll_lock(futex) \ + (void) ({ int ignore1, ignore2; \ + __asm __volatile ("cmpl $0, __libc_locking_needed\n\t" \ + "je,pt 0f\n\t" \ + "lock\n" \ + "0:\txaddl %0, %2\n\t" \ + "jne 1f\n\t" \ + ".subsection 1\n" \ + "1:\tleal %2, %%ecx\n\t" \ + "call __lll_lock_wait\n\t" \ + "jmp 2f\n\t" \ + ".previous\n" \ + "2:" \ + : "=a" (ignore1), "=&c" (ignore2), "=m" (futex) \ + : "0" (-1), "2" (futex) \ + : "memory"); }) + + +# define lll_unlock(futex) \ + (void) ({ int ignore; \ + __asm __volatile ("cmpl $0, __libc_locking_needed\n\t" \ + "je,pt 0f\n\t" \ + "lock\n" \ + "0:\tincl %0\n\t" \ + "jng 1f\n\t" \ + ".subsection 1\n" \ + "1:\tleal %0, %%eax\n\t" \ + "call __lll_unlock_wake\n\t" \ + "jmp 2f\n\t" \ + ".previous\n" \ + "2:" \ + : "=m" (futex), "=&a" (ignore) \ + : "0" (futex) \ + : "memory"); }) +#endif #define lll_islocked(futex) \ diff --git a/nptl/sysdeps/unix/sysv/linux/fork-gen.c b/nptl/sysdeps/unix/sysv/linux/libc_pthread_init.c similarity index 74% rename from nptl/sysdeps/unix/sysv/linux/fork-gen.c rename to nptl/sysdeps/unix/sysv/linux/libc_pthread_init.c index ff00261..d7f1c03 100644 --- a/nptl/sysdeps/unix/sysv/linux/fork-gen.c +++ b/nptl/sysdeps/unix/sysv/linux/libc_pthread_init.c @@ -19,19 +19,29 @@ #include #include "fork.h" +#include static struct fork_handler pthread_child_handler; +/* Global variable signalled when locking is needed. */ +int __libc_locking_needed; + void -__register_pthread_fork_handler (ptr, reclaim) +__libc_pthread_init (ptr, reclaim) unsigned long int *ptr; void (*reclaim) (void); { + /* Remember the pointer to the generation counter in libpthread. */ __fork_generation_pointer = ptr; + /* Called by a child after fork. */ pthread_child_handler.handler = reclaim; + /* The fork handler needed by libpthread. */ list_add_tail (&pthread_child_handler.list, &__fork_child_list); + + /* Signal the internal locking code that locking is needed now. */ + __libc_locking_needed = 1; } -- 2.7.4