diff options
author | Waldemar Brodkorb <wbx@openadk.org> | 2015-02-14 23:04:02 -0600 |
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committer | Waldemar Brodkorb <wbx@openadk.org> | 2015-02-14 23:04:02 -0600 |
commit | e1e46622ac0fce73d802fa4a8a2e83cc25cd9e7a (patch) | |
tree | 2c8d14e4dcc733f4227f0984ed05da5826b13acd /libpthread/linuxthreads/sysdeps/x86_64 | |
parent | 6b6ede3d15f04fe825cfa9f697507457e3640344 (diff) |
Revert "resolve merge"
This reverts commit 6b6ede3d15f04fe825cfa9f697507457e3640344.
Diffstat (limited to 'libpthread/linuxthreads/sysdeps/x86_64')
-rw-r--r-- | libpthread/linuxthreads/sysdeps/x86_64/pspinlock.c | 96 | ||||
-rw-r--r-- | libpthread/linuxthreads/sysdeps/x86_64/pt-machine.h | 156 | ||||
-rw-r--r-- | libpthread/linuxthreads/sysdeps/x86_64/tcb-offsets.sym | 4 |
3 files changed, 246 insertions, 10 deletions
diff --git a/libpthread/linuxthreads/sysdeps/x86_64/pspinlock.c b/libpthread/linuxthreads/sysdeps/x86_64/pspinlock.c new file mode 100644 index 000000000..80c1b05a8 --- /dev/null +++ b/libpthread/linuxthreads/sysdeps/x86_64/pspinlock.c @@ -0,0 +1,96 @@ +/* POSIX spinlock implementation. x86-64 version. + Copyright (C) 2001 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + 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, see + <http://www.gnu.org/licenses/>. */ + +#include <errno.h> +#include <pthread.h> +#include "internals.h" + +/* This implementation is similar to the one used in the Linux kernel. + But the kernel is byte instructions for the memory access. This is + faster but unusable here. The problem is that only 128 + threads/processes could use the spinlock at the same time. If (by + a design error in the program) a thread/process would hold the + spinlock for a time long enough to accumulate 128 waiting + processes, the next one will find a positive value in the spinlock + and assume it is unlocked. We cannot accept that. */ + +int +__pthread_spin_lock (pthread_spinlock_t *lock) +{ + __asm__ __volatile__ + ("\n" + "1:\n\t" + "lock; decl %0\n\t" + "js 2f\n\t" + ".section .text.spinlock,\"ax\"\n" + "2:\n\t" + "cmpl $0,%0\n\t" + "rep; nop\n\t" + "jle 2b\n\t" + "jmp 1b\n\t" + ".previous" + : "=m" (*lock)); + return 0; +} +weak_alias (__pthread_spin_lock, pthread_spin_lock) + + +int +__pthread_spin_trylock (pthread_spinlock_t *lock) +{ + int oldval; + + __asm__ __volatile__ + ("xchgl %0,%1" + : "=r" (oldval), "=m" (*lock) + : "0" (0)); + return oldval > 0 ? 0 : EBUSY; +} +weak_alias (__pthread_spin_trylock, pthread_spin_trylock) + + +int +__pthread_spin_unlock (pthread_spinlock_t *lock) +{ + __asm__ __volatile__ + ("movl $1,%0" + : "=m" (*lock)); + return 0; +} +weak_alias (__pthread_spin_unlock, pthread_spin_unlock) + + +int +__pthread_spin_init (pthread_spinlock_t *lock, int pshared) +{ + /* We can ignore the `pshared' parameter. Since we are busy-waiting + all processes which can access the memory location `lock' points + to can use the spinlock. */ + *lock = 1; + return 0; +} +weak_alias (__pthread_spin_init, pthread_spin_init) + + +int +__pthread_spin_destroy (pthread_spinlock_t *lock) +{ + /* Nothing to do. */ + return 0; +} +weak_alias (__pthread_spin_destroy, pthread_spin_destroy) diff --git a/libpthread/linuxthreads/sysdeps/x86_64/pt-machine.h b/libpthread/linuxthreads/sysdeps/x86_64/pt-machine.h index ed1fa30b1..0e0851e1e 100644 --- a/libpthread/linuxthreads/sysdeps/x86_64/pt-machine.h +++ b/libpthread/linuxthreads/sysdeps/x86_64/pt-machine.h @@ -20,7 +20,7 @@ #ifndef _PT_MACHINE_H #define _PT_MACHINE_H 1 -#include <features.h> +# include <features.h> #ifndef __ASSEMBLER__ # include <stddef.h> /* For offsetof. */ @@ -32,9 +32,6 @@ # define PT_EI __extern_always_inline # endif -extern long int testandset (int *); -extern int __compare_and_swap (long int *, long int, long int); - /* Get some notion of the current stack. Need not be exactly the top of the stack, just something somewhere in the current frame. */ # define CURRENT_STACK_FRAME stack_pointer @@ -43,14 +40,14 @@ register char * stack_pointer __asm__ ("%rsp") __attribute_used__; /* Spinlock implementation; required. */ PT_EI long int -testandset (int *__spinlock) +testandset (int *spinlock) { long int ret; __asm__ __volatile__ ( "xchgl %k0, %1" - : "=r"(ret), "=m"(*__spinlock) - : "0"(1), "m"(*__spinlock) + : "=r"(ret), "=m"(*spinlock) + : "0"(1), "m"(*spinlock) : "memory"); return ret; @@ -61,18 +58,157 @@ testandset (int *__spinlock) # define HAS_COMPARE_AND_SWAP PT_EI int -__compare_and_swap (long int *__p, long int __oldval, long int __newval) +__compare_and_swap (long int *p, long int oldval, long int newval) { char ret; long int readval; __asm__ __volatile__ ("lock; cmpxchgq %3, %1; sete %0" - : "=q" (ret), "=m" (*__p), "=a" (readval) - : "r" (__newval), "m" (*__p), "a" (__oldval) + : "=q" (ret), "=m" (*p), "=a" (readval) + : "r" (newval), "m" (*p), "a" (oldval) : "memory"); return ret; } +/* Return the thread descriptor for the current thread. + + The contained asm must *not* be marked volatile since otherwise + assignments like + pthread_descr self = thread_self(); + do not get optimized away. */ +# define THREAD_SELF \ +({ \ + register pthread_descr __self; \ + __asm__ ("movq %%fs:%c1,%0" : "=r" (__self) \ + : "i" (offsetof (struct _pthread_descr_struct, \ + p_header.data.self))); \ + __self; \ +}) + +/* Prototype for the system call. */ +extern int arch_prctl (int __code, unsigned long __addr); + +/* Initialize the thread-unique value. */ +# define INIT_THREAD_SELF(descr, nr) \ +{ \ + if (arch_prctl (ARCH_SET_FS, (unsigned long)descr) != 0) \ + abort (); \ +} + +/* Read member of the thread descriptor directly. */ +# define THREAD_GETMEM(descr, member) \ +({ \ + __typeof__ (descr->member) __value; \ + if (sizeof (__value) == 1) \ + __asm__ __volatile__ ("movb %%fs:%P2,%b0" \ + : "=q" (__value) \ + : "0" (0), \ + "i" (offsetof (struct _pthread_descr_struct, \ + member))); \ + else if (sizeof (__value) == 4) \ + __asm__ __volatile__ ("movl %%fs:%P2,%k0" \ + : "=r" (__value) \ + : "0" (0), \ + "i" (offsetof (struct _pthread_descr_struct, \ + member))); \ + else \ + { \ + if (sizeof (__value) != 8) \ + /* There should not be any value with a size other than 1, 4 or 8. */\ + abort (); \ + \ + __asm__ __volatile__ ("movq %%fs:%P1,%0" \ + : "=r" (__value) \ + : "i" (offsetof (struct _pthread_descr_struct, \ + member))); \ + } \ + __value; \ +}) + +/* Same as THREAD_GETMEM, but the member offset can be non-constant. */ +# define THREAD_GETMEM_NC(descr, member) \ +({ \ + __typeof__ (descr->member) __value; \ + if (sizeof (__value) == 1) \ + __asm__ __volatile__ ("movb %%fs:(%2),%b0" \ + : "=q" (__value) \ + : "0" (0), \ + "r" (offsetof (struct _pthread_descr_struct, \ + member))); \ + else if (sizeof (__value) == 4) \ + __asm__ __volatile__ ("movl %%fs:(%2),%k0" \ + : "=r" (__value) \ + : "0" (0), \ + "r" (offsetof (struct _pthread_descr_struct, \ + member))); \ + else \ + { \ + if (sizeof (__value) != 8) \ + /* There should not be any value with a size other than 1, 4 or 8. */\ + abort (); \ + \ + __asm__ __volatile__ ("movq %%fs:(%1),%0" \ + : "=r" (__value) \ + : "r" (offsetof (struct _pthread_descr_struct, \ + member))); \ + } \ + __value; \ +}) + +/* Set member of the thread descriptor directly. */ +# define THREAD_SETMEM(descr, member, value) \ +({ \ + __typeof__ (descr->member) __value = (value); \ + if (sizeof (__value) == 1) \ + __asm__ __volatile__ ("movb %0,%%fs:%P1" : \ + : "q" (__value), \ + "i" (offsetof (struct _pthread_descr_struct, \ + member))); \ + else if (sizeof (__value) == 4) \ + __asm__ __volatile__ ("movl %k0,%%fs:%P1" : \ + : "r" (__value), \ + "i" (offsetof (struct _pthread_descr_struct, \ + member))); \ + else \ + { \ + if (sizeof (__value) != 8) \ + /* There should not be any value with a size other than 1, 4 or 8. */\ + abort (); \ + \ + __asm__ __volatile__ ("movq %0,%%fs:%P1" : \ + : "r" (__value), \ + "i" (offsetof (struct _pthread_descr_struct, \ + member))); \ + } \ +}) + +/* Same as THREAD_SETMEM, but the member offset can be non-constant. */ +# define THREAD_SETMEM_NC(descr, member, value) \ +({ \ + __typeof__ (descr->member) __value = (value); \ + if (sizeof (__value) == 1) \ + __asm__ __volatile__ ("movb %0,%%fs:(%1)" : \ + : "q" (__value), \ + "r" (offsetof (struct _pthread_descr_struct, \ + member))); \ + else if (sizeof (__value) == 4) \ + __asm__ __volatile__ ("movl %k0,%%fs:(%1)" : \ + : "r" (__value), \ + "r" (offsetof (struct _pthread_descr_struct, \ + member))); \ + else \ + { \ + if (sizeof (__value) != 8) \ + /* There should not be any value with a size other than 1, 4 or 8. */\ + abort (); \ + \ + __asm__ __volatile__ ("movq %0,%%fs:(%1)" : \ + : "r" (__value), \ + "r" (offsetof (struct _pthread_descr_struct, \ + member))); \ + } \ +}) + #endif /* !__ASSEMBLER__ */ /* We want the OS to assign stack addresses. */ diff --git a/libpthread/linuxthreads/sysdeps/x86_64/tcb-offsets.sym b/libpthread/linuxthreads/sysdeps/x86_64/tcb-offsets.sym new file mode 100644 index 000000000..aee6be257 --- /dev/null +++ b/libpthread/linuxthreads/sysdeps/x86_64/tcb-offsets.sym @@ -0,0 +1,4 @@ +#include <sysdep.h> +#include <tls.h> + +MULTIPLE_THREADS_OFFSET offsetof (tcbhead_t, multiple_threads) |