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author | Adhemerval Zanella <adhemerval.zanella@linaro.org> | 2019-02-21 13:33:54 -0300 |
---|---|---|
committer | Adhemerval Zanella <adhemerval.zanella@linaro.org> | 2019-05-14 08:48:02 -0300 |
commit | c50e1c263ec15e98da3235e663049156fd1afcfa (patch) | |
tree | 47d22df898622b32fdc262f830978f29d6fa800e /sysdeps | |
parent | 959aff9fa22c45e0fa11cd88c9f8ea10bd9ba494 (diff) | |
download | glibc-c50e1c263ec15e98da3235e663049156fd1afcfa.zip glibc-c50e1c263ec15e98da3235e663049156fd1afcfa.tar.gz glibc-c50e1c263ec15e98da3235e663049156fd1afcfa.tar.bz2 |
x86: Remove arch-specific low level lock implementation
This patch removes the arch-specific x86 assembly implementation for
low level locking and consolidate both 64 bits and 32 bits in a
single implementation.
Different than other architectures, x86 lll_trylock, lll_lock, and
lll_unlock implements a single-thread optimization to avoid atomic
operation, using cmpxchgl instead. This patch implements by using
the new single-thread.h definitions in a generic way, although using
the previous semantic.
The lll_cond_trylock, lll_cond_lock, and lll_timedlock just use
atomic operations plus calls to lll_lock_wait*.
For __lll_lock_wait_private and __lll_lock_wait the generic implemtation
there is no indication that assembly implementation is required
performance-wise.
Checked on x86_64-linux-gnu and i686-linux-gnu.
* sysdeps/nptl/lowlevellock.h (__lll_trylock): New macro.
(lll_trylock): Call __lll_trylock.
* sysdeps/unix/sysv/linux/i386/libc-lowlevellock.S: Remove file.
* sysdeps/unix/sysv/linux/i386/lll_timedlock_wait.c: Likewise.
* sysdeps/unix/sysv/linux/i386/lowlevellock.S: Likewise.
* sysdeps/unix/sysv/linux/i386/lowlevellock.h: Likewise.
* sysdeps/unix/sysv/linux/x86_64/libc-lowlevellock.S: Likewise.
* sysdeps/unix/sysv/linux/x86_64/lll_timedlock_wait.c: Likewise.
* sysdeps/unix/sysv/linux/x86_64/lowlevellock.S: Likewise.
* sysdeps/unix/sysv/linux/x86_64/lowlevellock.h: Likewise.
* sysdeps/unix/sysv/linux/x86/lowlevellock.h: New file.
* sysdeps/unix/sysv/linux/x86_64/cancellation.S: Include
lowlevellock-futex.h.
Diffstat (limited to 'sysdeps')
-rw-r--r-- | sysdeps/nptl/lowlevellock.h | 4 | ||||
-rw-r--r-- | sysdeps/unix/sysv/linux/i386/libc-lowlevellock.S | 19 | ||||
-rw-r--r-- | sysdeps/unix/sysv/linux/i386/lll_timedlock_wait.c | 1 | ||||
-rw-r--r-- | sysdeps/unix/sysv/linux/i386/lowlevellock.S | 268 | ||||
-rw-r--r-- | sysdeps/unix/sysv/linux/i386/lowlevellock.h | 240 | ||||
-rw-r--r-- | sysdeps/unix/sysv/linux/x86/lowlevellock.h | 110 | ||||
-rw-r--r-- | sysdeps/unix/sysv/linux/x86_64/cancellation.S | 2 | ||||
-rw-r--r-- | sysdeps/unix/sysv/linux/x86_64/libc-lowlevellock.S | 19 | ||||
-rw-r--r-- | sysdeps/unix/sysv/linux/x86_64/lll_timedlock_wait.c | 1 | ||||
-rw-r--r-- | sysdeps/unix/sysv/linux/x86_64/lowlevellock.S | 233 | ||||
-rw-r--r-- | sysdeps/unix/sysv/linux/x86_64/lowlevellock.h | 243 |
11 files changed, 114 insertions, 1026 deletions
diff --git a/sysdeps/nptl/lowlevellock.h b/sysdeps/nptl/lowlevellock.h index 6f017af..e905829 100644 --- a/sysdeps/nptl/lowlevellock.h +++ b/sysdeps/nptl/lowlevellock.h @@ -63,8 +63,10 @@ /* If LOCK is 0 (not acquired), set to 1 (acquired with no waiters) and return 0. Otherwise leave lock unchanged and return non-zero to indicate that the lock was not acquired. */ +#define __lll_trylock(lock) \ + __glibc_unlikely (atomic_compare_and_exchange_bool_acq ((lock), 1, 0)) #define lll_trylock(lock) \ - __glibc_unlikely (atomic_compare_and_exchange_bool_acq (&(lock), 1, 0)) + __lll_trylock (&(lock)) /* If LOCK is 0 (not acquired), set to 2 (acquired, possibly with waiters) and return 0. Otherwise leave lock unchanged and return non-zero to indicate diff --git a/sysdeps/unix/sysv/linux/i386/libc-lowlevellock.S b/sysdeps/unix/sysv/linux/i386/libc-lowlevellock.S deleted file mode 100644 index 3202527..0000000 --- a/sysdeps/unix/sysv/linux/i386/libc-lowlevellock.S +++ /dev/null @@ -1,19 +0,0 @@ -/* Copyright (C) 2002-2019 Free Software Foundation, Inc. - This file is part of the GNU C Library. - Contributed by Ulrich Drepper <drepper@redhat.com>, 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, see - <http://www.gnu.org/licenses/>. */ - -#include "lowlevellock.S" diff --git a/sysdeps/unix/sysv/linux/i386/lll_timedlock_wait.c b/sysdeps/unix/sysv/linux/i386/lll_timedlock_wait.c deleted file mode 100644 index f6875b8..0000000 --- a/sysdeps/unix/sysv/linux/i386/lll_timedlock_wait.c +++ /dev/null @@ -1 +0,0 @@ -/* __lll_timedlock_wait is in lowlevellock.S. */ diff --git a/sysdeps/unix/sysv/linux/i386/lowlevellock.S b/sysdeps/unix/sysv/linux/i386/lowlevellock.S deleted file mode 100644 index a9898e9..0000000 --- a/sysdeps/unix/sysv/linux/i386/lowlevellock.S +++ /dev/null @@ -1,268 +0,0 @@ -/* Copyright (C) 2002-2019 Free Software Foundation, Inc. - This file is part of the GNU C Library. - Contributed by Ulrich Drepper <drepper@redhat.com>, 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, see - <http://www.gnu.org/licenses/>. */ - -#include <sysdep.h> -#include <pthread-errnos.h> -#include <kernel-features.h> -#include <lowlevellock.h> - -#include <stap-probe.h> - - .text - -#define LOAD_PRIVATE_FUTEX_WAIT(reg) \ - movl $(FUTEX_WAIT | FUTEX_PRIVATE_FLAG), reg -#define LOAD_PRIVATE_FUTEX_WAKE(reg) \ - movl $(FUTEX_WAKE | FUTEX_PRIVATE_FLAG), reg -#define LOAD_FUTEX_WAIT(reg) \ - xorl $(FUTEX_WAIT | FUTEX_PRIVATE_FLAG), reg -#define LOAD_FUTEX_WAIT_ABS(reg) \ - xorl $(FUTEX_WAIT_BITSET | FUTEX_PRIVATE_FLAG | FUTEX_CLOCK_REALTIME), reg -#define LOAD_FUTEX_WAKE(reg) \ - xorl $(FUTEX_WAKE | FUTEX_PRIVATE_FLAG), reg - - .globl __lll_lock_wait_private - .type __lll_lock_wait_private,@function - .hidden __lll_lock_wait_private - .align 16 -__lll_lock_wait_private: - cfi_startproc - pushl %edx - cfi_adjust_cfa_offset(4) - pushl %ebx - cfi_adjust_cfa_offset(4) - pushl %esi - cfi_adjust_cfa_offset(4) - cfi_offset(%edx, -8) - cfi_offset(%ebx, -12) - cfi_offset(%esi, -16) - - movl $2, %edx - movl %ecx, %ebx - xorl %esi, %esi /* No timeout. */ - LOAD_PRIVATE_FUTEX_WAIT (%ecx) - - cmpl %edx, %eax /* NB: %edx == 2 */ - jne 2f - -1: LIBC_PROBE (lll_lock_wait_private, 1, %ebx) - movl $SYS_futex, %eax - ENTER_KERNEL - -2: movl %edx, %eax - xchgl %eax, (%ebx) /* NB: lock is implied */ - - testl %eax, %eax - jnz 1b - - popl %esi - cfi_adjust_cfa_offset(-4) - cfi_restore(%esi) - popl %ebx - cfi_adjust_cfa_offset(-4) - cfi_restore(%ebx) - popl %edx - cfi_adjust_cfa_offset(-4) - cfi_restore(%edx) - ret - cfi_endproc - .size __lll_lock_wait_private,.-__lll_lock_wait_private - -#if !IS_IN (libc) - .globl __lll_lock_wait - .type __lll_lock_wait,@function - .hidden __lll_lock_wait - .align 16 -__lll_lock_wait: - cfi_startproc - pushl %edx - cfi_adjust_cfa_offset(4) - pushl %ebx - cfi_adjust_cfa_offset(4) - pushl %esi - cfi_adjust_cfa_offset(4) - cfi_offset(%edx, -8) - cfi_offset(%ebx, -12) - cfi_offset(%esi, -16) - - movl %edx, %ebx - movl $2, %edx - xorl %esi, %esi /* No timeout. */ - LOAD_FUTEX_WAIT (%ecx) - - cmpl %edx, %eax /* NB: %edx == 2 */ - jne 2f - -1: movl $SYS_futex, %eax - ENTER_KERNEL - -2: movl %edx, %eax - xchgl %eax, (%ebx) /* NB: lock is implied */ - - testl %eax, %eax - jnz 1b - - popl %esi - cfi_adjust_cfa_offset(-4) - cfi_restore(%esi) - popl %ebx - cfi_adjust_cfa_offset(-4) - cfi_restore(%ebx) - popl %edx - cfi_adjust_cfa_offset(-4) - cfi_restore(%edx) - ret - cfi_endproc - .size __lll_lock_wait,.-__lll_lock_wait - - /* %ecx: futex - %esi: flags - %edx: timeout - %eax: futex value - */ - .globl __lll_timedlock_wait - .type __lll_timedlock_wait,@function - .hidden __lll_timedlock_wait - .align 16 -__lll_timedlock_wait: - cfi_startproc - pushl %ebp - cfi_adjust_cfa_offset(4) - cfi_rel_offset(%ebp, 0) - pushl %ebx - cfi_adjust_cfa_offset(4) - cfi_rel_offset(%ebx, 0) - - cmpl $0, (%edx) - js 8f - - movl %ecx, %ebx - movl %esi, %ecx - movl %edx, %esi - movl $0xffffffff, %ebp - LOAD_FUTEX_WAIT_ABS (%ecx) - - movl $2, %edx - cmpl %edx, %eax - jne 2f - -1: movl $SYS_futex, %eax - movl $2, %edx - ENTER_KERNEL - -2: xchgl %edx, (%ebx) /* NB: lock is implied */ - - testl %edx, %edx - jz 3f - - cmpl $-ETIMEDOUT, %eax - je 4f - cmpl $-EINVAL, %eax - jne 1b -4: movl %eax, %edx - negl %edx - -3: movl %edx, %eax -7: popl %ebx - cfi_adjust_cfa_offset(-4) - cfi_restore(%ebx) - popl %ebp - cfi_adjust_cfa_offset(-4) - cfi_restore(%ebp) - ret - -8: movl $ETIMEDOUT, %eax - jmp 7b - - cfi_endproc - .size __lll_timedlock_wait,.-__lll_timedlock_wait -#endif - - .globl __lll_unlock_wake_private - .type __lll_unlock_wake_private,@function - .hidden __lll_unlock_wake_private - .align 16 -__lll_unlock_wake_private: - cfi_startproc - pushl %ebx - cfi_adjust_cfa_offset(4) - pushl %ecx - cfi_adjust_cfa_offset(4) - pushl %edx - cfi_adjust_cfa_offset(4) - cfi_offset(%ebx, -8) - cfi_offset(%ecx, -12) - cfi_offset(%edx, -16) - - movl %eax, %ebx - movl $0, (%eax) - LOAD_PRIVATE_FUTEX_WAKE (%ecx) - movl $1, %edx /* Wake one thread. */ - movl $SYS_futex, %eax - ENTER_KERNEL - - popl %edx - cfi_adjust_cfa_offset(-4) - cfi_restore(%edx) - popl %ecx - cfi_adjust_cfa_offset(-4) - cfi_restore(%ecx) - popl %ebx - cfi_adjust_cfa_offset(-4) - cfi_restore(%ebx) - ret - cfi_endproc - .size __lll_unlock_wake_private,.-__lll_unlock_wake_private - -#if !IS_IN (libc) - .globl __lll_unlock_wake - .type __lll_unlock_wake,@function - .hidden __lll_unlock_wake - .align 16 -__lll_unlock_wake: - cfi_startproc - pushl %ebx - cfi_adjust_cfa_offset(4) - pushl %ecx - cfi_adjust_cfa_offset(4) - pushl %edx - cfi_adjust_cfa_offset(4) - cfi_offset(%ebx, -8) - cfi_offset(%ecx, -12) - cfi_offset(%edx, -16) - - movl %eax, %ebx - movl $0, (%eax) - LOAD_FUTEX_WAKE (%ecx) - movl $1, %edx /* Wake one thread. */ - movl $SYS_futex, %eax - ENTER_KERNEL - - popl %edx - cfi_adjust_cfa_offset(-4) - cfi_restore(%edx) - popl %ecx - cfi_adjust_cfa_offset(-4) - cfi_restore(%ecx) - popl %ebx - cfi_adjust_cfa_offset(-4) - cfi_restore(%ebx) - ret - cfi_endproc - .size __lll_unlock_wake,.-__lll_unlock_wake -#endif diff --git a/sysdeps/unix/sysv/linux/i386/lowlevellock.h b/sysdeps/unix/sysv/linux/i386/lowlevellock.h deleted file mode 100644 index 94dccc4..0000000 --- a/sysdeps/unix/sysv/linux/i386/lowlevellock.h +++ /dev/null @@ -1,240 +0,0 @@ -/* Copyright (C) 2002-2019 Free Software Foundation, Inc. - This file is part of the GNU C Library. - Contributed by Ulrich Drepper <drepper@redhat.com>, 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, see - <http://www.gnu.org/licenses/>. */ - -#ifndef _LOWLEVELLOCK_H -#define _LOWLEVELLOCK_H 1 - -#ifndef __ASSEMBLER__ -# include <time.h> -# include <sys/param.h> -# include <bits/pthreadtypes.h> -# include <kernel-features.h> -/* <tcb-offsets.h> is generated from tcb-offsets.sym to define offsets - and sizes of types in <tls.h> as well as <pthread.h> which includes - <lowlevellock.h> via nptl/descr.h. Don't include <tcb-offsets.h> - when generating <tcb-offsets.h> to avoid circular dependency which - may lead to build hang on a many-core machine. */ -# ifndef GEN_AS_CONST_HEADERS -# include <tcb-offsets.h> -# endif - -# ifndef LOCK_INSTR -# ifdef UP -# define LOCK_INSTR /* nothing */ -# else -# define LOCK_INSTR "lock;" -# endif -# endif -#else -# ifndef LOCK -# ifdef UP -# define LOCK -# else -# define LOCK lock -# endif -# endif -#endif - -#include <lowlevellock-futex.h> - -/* XXX Remove when no assembler code uses futexes anymore. */ -#define SYS_futex __NR_futex - -#ifndef __ASSEMBLER__ - -/* Initializer for compatibility lock. */ -#define LLL_LOCK_INITIALIZER (0) -#define LLL_LOCK_INITIALIZER_LOCKED (1) -#define LLL_LOCK_INITIALIZER_WAITERS (2) - - -/* NB: in the lll_trylock macro we simply return the value in %eax - after the cmpxchg instruction. In case the operation succeded this - value is zero. In case the operation failed, the cmpxchg instruction - has loaded the current value of the memory work which is guaranteed - to be nonzero. */ -#if !IS_IN (libc) || defined UP -# define __lll_trylock_asm LOCK_INSTR "cmpxchgl %2, %1" -#else -# define __lll_trylock_asm "cmpl $0, %%gs:%P5\n\t" \ - "je 0f\n\t" \ - "lock\n" \ - "0:\tcmpxchgl %2, %1" -#endif - -#define lll_trylock(futex) \ - ({ int ret; \ - __asm __volatile (__lll_trylock_asm \ - : "=a" (ret), "=m" (futex) \ - : "r" (LLL_LOCK_INITIALIZER_LOCKED), "m" (futex), \ - "0" (LLL_LOCK_INITIALIZER), \ - "i" (MULTIPLE_THREADS_OFFSET) \ - : "memory"); \ - ret; }) - - -#define lll_cond_trylock(futex) \ - ({ int ret; \ - __asm __volatile (LOCK_INSTR "cmpxchgl %2, %1" \ - : "=a" (ret), "=m" (futex) \ - : "r" (LLL_LOCK_INITIALIZER_WAITERS), \ - "m" (futex), "0" (LLL_LOCK_INITIALIZER) \ - : "memory"); \ - ret; }) - -#if !IS_IN (libc) || defined UP -# define __lll_lock_asm_start LOCK_INSTR "cmpxchgl %1, %2\n\t" -#else -# define __lll_lock_asm_start "cmpl $0, %%gs:%P6\n\t" \ - "je 0f\n\t" \ - "lock\n" \ - "0:\tcmpxchgl %1, %2\n\t" -#endif - -#define lll_lock(futex, private) \ - (void) \ - ({ int ignore1, ignore2; \ - if (__builtin_constant_p (private) && (private) == LLL_PRIVATE) \ - __asm __volatile (__lll_lock_asm_start \ - "jz 18f\n\t" \ - "1:\tleal %2, %%ecx\n" \ - "2:\tcall __lll_lock_wait_private\n" \ - "18:" \ - : "=a" (ignore1), "=c" (ignore2), "=m" (futex) \ - : "0" (0), "1" (1), "m" (futex), \ - "i" (MULTIPLE_THREADS_OFFSET) \ - : "memory"); \ - else \ - { \ - int ignore3; \ - __asm __volatile (__lll_lock_asm_start \ - "jz 18f\n\t" \ - "1:\tleal %2, %%edx\n" \ - "0:\tmovl %8, %%ecx\n" \ - "2:\tcall __lll_lock_wait\n" \ - "18:" \ - : "=a" (ignore1), "=c" (ignore2), \ - "=m" (futex), "=&d" (ignore3) \ - : "1" (1), "m" (futex), \ - "i" (MULTIPLE_THREADS_OFFSET), "0" (0), \ - "g" ((int) (private)) \ - : "memory"); \ - } \ - }) - - -/* Special version of lll_lock which causes the unlock function to - always wakeup waiters. */ -#define lll_cond_lock(futex, private) \ - (void) \ - ({ int ignore1, ignore2, ignore3; \ - __asm __volatile (LOCK_INSTR "cmpxchgl %1, %2\n\t" \ - "jz 18f\n\t" \ - "1:\tleal %2, %%edx\n" \ - "0:\tmovl %7, %%ecx\n" \ - "2:\tcall __lll_lock_wait\n" \ - "18:" \ - : "=a" (ignore1), "=c" (ignore2), "=m" (futex), \ - "=&d" (ignore3) \ - : "0" (0), "1" (2), "m" (futex), "g" ((int) (private))\ - : "memory"); \ - }) - - -#define lll_timedlock(futex, timeout, private) \ - ({ int result, ignore1, ignore2, ignore3; \ - __asm __volatile (LOCK_INSTR "cmpxchgl %1, %3\n\t" \ - "jz 18f\n\t" \ - "1:\tleal %3, %%ecx\n" \ - "0:\tmovl %8, %%edx\n" \ - "2:\tcall __lll_timedlock_wait\n" \ - "18:" \ - : "=a" (result), "=c" (ignore1), "=&d" (ignore2), \ - "=m" (futex), "=S" (ignore3) \ - : "0" (0), "1" (1), "m" (futex), "m" (timeout), \ - "4" ((int) (private)) \ - : "memory"); \ - result; }) - -extern int __lll_timedlock_elision (int *futex, short *adapt_count, - const struct timespec *timeout, - int private) attribute_hidden; - -#define lll_timedlock_elision(futex, adapt_count, timeout, private) \ - __lll_timedlock_elision(&(futex), &(adapt_count), timeout, private) - -#if !IS_IN (libc) || defined UP -# define __lll_unlock_asm LOCK_INSTR "subl $1, %0\n\t" -#else -# define __lll_unlock_asm "cmpl $0, %%gs:%P3\n\t" \ - "je 0f\n\t" \ - "lock\n" \ - "0:\tsubl $1,%0\n\t" -#endif - -#define lll_unlock(futex, private) \ - (void) \ - ({ int ignore; \ - if (__builtin_constant_p (private) && (private) == LLL_PRIVATE) \ - __asm __volatile (__lll_unlock_asm \ - "je 18f\n\t" \ - "1:\tleal %0, %%eax\n" \ - "2:\tcall __lll_unlock_wake_private\n" \ - "18:" \ - : "=m" (futex), "=&a" (ignore) \ - : "m" (futex), "i" (MULTIPLE_THREADS_OFFSET) \ - : "memory"); \ - else \ - { \ - int ignore2; \ - __asm __volatile (__lll_unlock_asm \ - "je 18f\n\t" \ - "1:\tleal %0, %%eax\n" \ - "0:\tmovl %5, %%ecx\n" \ - "2:\tcall __lll_unlock_wake\n" \ - "18:" \ - : "=m" (futex), "=&a" (ignore), "=&c" (ignore2) \ - : "i" (MULTIPLE_THREADS_OFFSET), "m" (futex), \ - "g" ((int) (private)) \ - : "memory"); \ - } \ - }) - - -#define lll_islocked(futex) \ - (futex != LLL_LOCK_INITIALIZER) - -extern int __lll_lock_elision (int *futex, short *adapt_count, int private) - attribute_hidden; - -extern int __lll_unlock_elision(int *lock, int private) - attribute_hidden; - -extern int __lll_trylock_elision(int *lock, short *adapt_count) - attribute_hidden; - -#define lll_lock_elision(futex, adapt_count, private) \ - __lll_lock_elision (&(futex), &(adapt_count), private) -#define lll_unlock_elision(futex, adapt_count, private) \ - __lll_unlock_elision (&(futex), private) -#define lll_trylock_elision(futex, adapt_count) \ - __lll_trylock_elision(&(futex), &(adapt_count)) - -#endif /* !__ASSEMBLER__ */ - -#endif /* lowlevellock.h */ diff --git a/sysdeps/unix/sysv/linux/x86/lowlevellock.h b/sysdeps/unix/sysv/linux/x86/lowlevellock.h new file mode 100644 index 0000000..8a78dcf --- /dev/null +++ b/sysdeps/unix/sysv/linux/x86/lowlevellock.h @@ -0,0 +1,110 @@ +/* Low-level lock implementation, x86 version. + Copyright (C) 2019 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/>. */ + +#ifndef _X86_64_LOWLEVELLOCK_H +#define _X86_64_LOWLEVELLOCK_H 1 + +#ifndef __ASSEMBLER__ +#include <sysdeps/nptl/lowlevellock.h> +#include <single-thread.h> + +/* The lll_trylock, lll_lock, and lll_unlock implements a single-thread + optimization using the cmpxchgl instruction. It checks if the process + is single thread and avoid a more expensive atomic instruction. */ + +/* The single-thread optimization only works for libc itself, we need + atomicity for libpthread in case of shared futexes. */ +#if !IS_IN(libc) +# define is_single_thread 0 +#else +# define is_single_thread SINGLE_THREAD_P +#endif + +/* In the __lllc_as we simply return the value in %eax after the cmpxchg + instruction. In case the operation succeeded this value is zero. In case + the operation failed, the cmpxchg instruction has loaded the current value + of the memory work which is guaranteed to be nonzero. */ +static inline int +__attribute__ ((always_inline)) +__lll_cas_lock (int *futex) +{ + int ret; + asm volatile ("cmpxchgl %2, %1" + : "=a" (ret), "=m" (*futex) + : "r" (1), "m" (*futex), "0" (0) + : "memory"); + return ret; +} + +#undef lll_trylock +#define lll_trylock(lock) \ + ({ \ + int __ret; \ + if (is_single_thread) \ + __ret = __lll_cas_lock (&(lock)); \ + else \ + __ret = __lll_trylock (&(lock)); \ + __ret; \ + }) + +#undef lll_lock +#define lll_lock(lock, private) \ + ((void) \ + ({ \ + if (is_single_thread) \ + __lll_cas_lock (&(lock)); \ + else \ + __lll_lock (&(lock), private); \ + })) + +#undef lll_unlock +#define lll_unlock(lock, private) \ + ((void) \ + ({ \ + if (is_single_thread) \ + (lock)--; \ + else \ + __lll_unlock (&(lock), private); \ + })) + +extern int __lll_timedlock_elision (int *futex, short *adapt_count, + const struct timespec *timeout, + int private) attribute_hidden; + +#define lll_timedlock_elision(futex, adapt_count, timeout, private) \ + __lll_timedlock_elision(&(futex), &(adapt_count), timeout, private) + +extern int __lll_lock_elision (int *futex, short *adapt_count, int private) + attribute_hidden; + +extern int __lll_unlock_elision (int *lock, int private) + attribute_hidden; + +extern int __lll_trylock_elision (int *lock, short *adapt_count) + attribute_hidden; + +#define lll_lock_elision(futex, adapt_count, private) \ + __lll_lock_elision (&(futex), &(adapt_count), private) +#define lll_unlock_elision(futex, adapt_count, private) \ + __lll_unlock_elision (&(futex), private) +#define lll_trylock_elision(futex, adapt_count) \ + __lll_trylock_elision (&(futex), &(adapt_count)) + +#endif /* !__ASSEMBLER__ */ + +#endif /* lowlevellock.h */ diff --git a/sysdeps/unix/sysv/linux/x86_64/cancellation.S b/sysdeps/unix/sysv/linux/x86_64/cancellation.S index 7d169d9..bb49107 100644 --- a/sysdeps/unix/sysv/linux/x86_64/cancellation.S +++ b/sysdeps/unix/sysv/linux/x86_64/cancellation.S @@ -19,7 +19,7 @@ #include <sysdep.h> #include <tcb-offsets.h> #include <kernel-features.h> -#include "lowlevellock.h" +#include <lowlevellock-futex.h> #define PTHREAD_UNWIND JUMPTARGET(__pthread_unwind) #if IS_IN (libpthread) diff --git a/sysdeps/unix/sysv/linux/x86_64/libc-lowlevellock.S b/sysdeps/unix/sysv/linux/x86_64/libc-lowlevellock.S deleted file mode 100644 index 3202527..0000000 --- a/sysdeps/unix/sysv/linux/x86_64/libc-lowlevellock.S +++ /dev/null @@ -1,19 +0,0 @@ -/* Copyright (C) 2002-2019 Free Software Foundation, Inc. - This file is part of the GNU C Library. - Contributed by Ulrich Drepper <drepper@redhat.com>, 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, see - <http://www.gnu.org/licenses/>. */ - -#include "lowlevellock.S" diff --git a/sysdeps/unix/sysv/linux/x86_64/lll_timedlock_wait.c b/sysdeps/unix/sysv/linux/x86_64/lll_timedlock_wait.c deleted file mode 100644 index f6875b8..0000000 --- a/sysdeps/unix/sysv/linux/x86_64/lll_timedlock_wait.c +++ /dev/null @@ -1 +0,0 @@ -/* __lll_timedlock_wait is in lowlevellock.S. */ diff --git a/sysdeps/unix/sysv/linux/x86_64/lowlevellock.S b/sysdeps/unix/sysv/linux/x86_64/lowlevellock.S deleted file mode 100644 index 00ba88d..0000000 --- a/sysdeps/unix/sysv/linux/x86_64/lowlevellock.S +++ /dev/null @@ -1,233 +0,0 @@ -/* Copyright (C) 2002-2019 Free Software Foundation, Inc. - This file is part of the GNU C Library. - Contributed by Ulrich Drepper <drepper@redhat.com>, 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, see - <http://www.gnu.org/licenses/>. */ - -#include <sysdep.h> -#include <pthread-errnos.h> -#include <kernel-features.h> -#include <lowlevellock.h> - -#include <stap-probe.h> - - .text - -#define LOAD_PRIVATE_FUTEX_WAIT(reg) \ - movl $(FUTEX_WAIT | FUTEX_PRIVATE_FLAG), reg -#define LOAD_PRIVATE_FUTEX_WAKE(reg) \ - movl $(FUTEX_WAKE | FUTEX_PRIVATE_FLAG), reg -#define LOAD_FUTEX_WAIT(reg) \ - xorl $(FUTEX_WAIT | FUTEX_PRIVATE_FLAG), reg -#define LOAD_FUTEX_WAIT_ABS(reg) \ - xorl $(FUTEX_WAIT_BITSET | FUTEX_PRIVATE_FLAG | FUTEX_CLOCK_REALTIME), reg -#define LOAD_FUTEX_WAKE(reg) \ - xorl $(FUTEX_WAKE | FUTEX_PRIVATE_FLAG), reg - - - .globl __lll_lock_wait_private - .type __lll_lock_wait_private,@function - .hidden __lll_lock_wait_private - .align 16 -__lll_lock_wait_private: - cfi_startproc - pushq %r10 - cfi_adjust_cfa_offset(8) - pushq %rdx - cfi_adjust_cfa_offset(8) - cfi_offset(%r10, -16) - cfi_offset(%rdx, -24) - xorq %r10, %r10 /* No timeout. */ - movl $2, %edx - LOAD_PRIVATE_FUTEX_WAIT (%esi) - - cmpl %edx, %eax /* NB: %edx == 2 */ - jne 2f - -1: LIBC_PROBE (lll_lock_wait_private, 1, %rdi) - movl $SYS_futex, %eax - syscall - -2: movl %edx, %eax - xchgl %eax, (%rdi) /* NB: lock is implied */ - - testl %eax, %eax - jnz 1b - - popq %rdx - cfi_adjust_cfa_offset(-8) - cfi_restore(%rdx) - popq %r10 - cfi_adjust_cfa_offset(-8) - cfi_restore(%r10) - retq - cfi_endproc - .size __lll_lock_wait_private,.-__lll_lock_wait_private - -#if !IS_IN (libc) - .globl __lll_lock_wait - .type __lll_lock_wait,@function - .hidden __lll_lock_wait - .align 16 -__lll_lock_wait: - cfi_startproc - pushq %r10 - cfi_adjust_cfa_offset(8) - pushq %rdx - cfi_adjust_cfa_offset(8) - cfi_offset(%r10, -16) - cfi_offset(%rdx, -24) - xorq %r10, %r10 /* No timeout. */ - movl $2, %edx - LOAD_FUTEX_WAIT (%esi) - - cmpl %edx, %eax /* NB: %edx == 2 */ - jne 2f - -1: LIBC_PROBE (lll_lock_wait, 2, %rdi, %rsi) - movl $SYS_futex, %eax - syscall - -2: movl %edx, %eax - xchgl %eax, (%rdi) /* NB: lock is implied */ - - testl %eax, %eax - jnz 1b - - popq %rdx - cfi_adjust_cfa_offset(-8) - cfi_restore(%rdx) - popq %r10 - cfi_adjust_cfa_offset(-8) - cfi_restore(%r10) - retq - cfi_endproc - .size __lll_lock_wait,.-__lll_lock_wait - - /* %rdi: futex - %rsi: flags - %rdx: timeout - %eax: futex value - */ - .globl __lll_timedlock_wait - .type __lll_timedlock_wait,@function - .hidden __lll_timedlock_wait - .align 16 -__lll_timedlock_wait: - cfi_startproc - cmpq $0, (%rdx) - js 5f - - pushq %r9 - cfi_adjust_cfa_offset(8) - cfi_rel_offset(%r9, 0) - - movq %rdx, %r10 - movl $0xffffffff, %r9d - LOAD_FUTEX_WAIT_ABS (%esi) - - movl $2, %edx - cmpl %edx, %eax - jne 2f - -1: movl $SYS_futex, %eax - movl $2, %edx - syscall - -2: xchgl %edx, (%rdi) /* NB: lock is implied */ - - testl %edx, %edx - jz 3f - - cmpl $-ETIMEDOUT, %eax - je 4f - cmpl $-EINVAL, %eax - jne 1b -4: movl %eax, %edx - negl %edx - -3: movl %edx, %eax - popq %r9 - cfi_adjust_cfa_offset(-8) - cfi_restore(%r9) - retq - -5: movl $ETIMEDOUT, %eax - retq - - cfi_endproc - .size __lll_timedlock_wait,.-__lll_timedlock_wait -#endif - - - .globl __lll_unlock_wake_private - .type __lll_unlock_wake_private,@function - .hidden __lll_unlock_wake_private - .align 16 -__lll_unlock_wake_private: - cfi_startproc - pushq %rsi - cfi_adjust_cfa_offset(8) - pushq %rdx - cfi_adjust_cfa_offset(8) - cfi_offset(%rsi, -16) - cfi_offset(%rdx, -24) - - movl $0, (%rdi) - LOAD_PRIVATE_FUTEX_WAKE (%esi) - movl $1, %edx /* Wake one thread. */ - movl $SYS_futex, %eax - syscall - - popq %rdx - cfi_adjust_cfa_offset(-8) - cfi_restore(%rdx) - popq %rsi - cfi_adjust_cfa_offset(-8) - cfi_restore(%rsi) - retq - cfi_endproc - .size __lll_unlock_wake_private,.-__lll_unlock_wake_private - -#if !IS_IN (libc) - .globl __lll_unlock_wake - .type __lll_unlock_wake,@function - .hidden __lll_unlock_wake - .align 16 -__lll_unlock_wake: - cfi_startproc - pushq %rsi - cfi_adjust_cfa_offset(8) - pushq %rdx - cfi_adjust_cfa_offset(8) - cfi_offset(%rsi, -16) - cfi_offset(%rdx, -24) - - movl $0, (%rdi) - LOAD_FUTEX_WAKE (%esi) - movl $1, %edx /* Wake one thread. */ - movl $SYS_futex, %eax - syscall - - popq %rdx - cfi_adjust_cfa_offset(-8) - cfi_restore(%rdx) - popq %rsi - cfi_adjust_cfa_offset(-8) - cfi_restore(%rsi) - retq - cfi_endproc - .size __lll_unlock_wake,.-__lll_unlock_wake -#endif diff --git a/sysdeps/unix/sysv/linux/x86_64/lowlevellock.h b/sysdeps/unix/sysv/linux/x86_64/lowlevellock.h deleted file mode 100644 index 8cbc1ca..0000000 --- a/sysdeps/unix/sysv/linux/x86_64/lowlevellock.h +++ /dev/null @@ -1,243 +0,0 @@ -/* Copyright (C) 2002-2019 Free Software Foundation, Inc. - This file is part of the GNU C Library. - Contributed by Ulrich Drepper <drepper@redhat.com>, 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, see - <http://www.gnu.org/licenses/>. */ - -#ifndef _LOWLEVELLOCK_H -#define _LOWLEVELLOCK_H 1 - -#ifndef __ASSEMBLER__ -# include <time.h> -# include <sys/param.h> -# include <bits/pthreadtypes.h> -# include <kernel-features.h> - -# ifndef LOCK_INSTR -# ifdef UP -# define LOCK_INSTR /* nothing */ -# else -# define LOCK_INSTR "lock;" -# endif -# endif -#else -# ifndef LOCK -# ifdef UP -# define LOCK -# else -# define LOCK lock -# endif -# endif -#endif - -#include <lowlevellock-futex.h> - -/* XXX Remove when no assembler code uses futexes anymore. */ -#define SYS_futex __NR_futex - -#ifndef __ASSEMBLER__ - -/* Initializer for lock. */ -#define LLL_LOCK_INITIALIZER (0) -#define LLL_LOCK_INITIALIZER_LOCKED (1) -#define LLL_LOCK_INITIALIZER_WAITERS (2) - - -/* NB: in the lll_trylock macro we simply return the value in %eax - after the cmpxchg instruction. In case the operation succeded this - value is zero. In case the operation failed, the cmpxchg instruction - has loaded the current value of the memory work which is guaranteed - to be nonzero. */ -#if !IS_IN (libc) || defined UP -# define __lll_trylock_asm LOCK_INSTR "cmpxchgl %2, %1" -#else -# define __lll_trylock_asm "cmpl $0, __libc_multiple_threads(%%rip)\n\t" \ - "je 0f\n\t" \ - "lock; cmpxchgl %2, %1\n\t" \ - "jmp 1f\n\t" \ - "0:\tcmpxchgl %2, %1\n\t" \ - "1:" -#endif - -#define lll_trylock(futex) \ - ({ int ret; \ - __asm __volatile (__lll_trylock_asm \ - : "=a" (ret), "=m" (futex) \ - : "r" (LLL_LOCK_INITIALIZER_LOCKED), "m" (futex), \ - "0" (LLL_LOCK_INITIALIZER) \ - : "memory"); \ - ret; }) - -#define lll_cond_trylock(futex) \ - ({ int ret; \ - __asm __volatile (LOCK_INSTR "cmpxchgl %2, %1" \ - : "=a" (ret), "=m" (futex) \ - : "r" (LLL_LOCK_INITIALIZER_WAITERS), \ - "m" (futex), "0" (LLL_LOCK_INITIALIZER) \ - : "memory"); \ - ret; }) - -#if !IS_IN (libc) || defined UP -# define __lll_lock_asm_start LOCK_INSTR "cmpxchgl %4, %2\n\t" \ - "jz 24f\n\t" -#else -# define __lll_lock_asm_start "cmpl $0, __libc_multiple_threads(%%rip)\n\t" \ - "je 0f\n\t" \ - "lock; cmpxchgl %4, %2\n\t" \ - "jnz 1f\n\t" \ - "jmp 24f\n" \ - "0:\tcmpxchgl %4, %2\n\t" \ - "jz 24f\n\t" -#endif - -#define lll_lock(futex, private) \ - (void) \ - ({ int ignore1, ignore2, ignore3; \ - if (__builtin_constant_p (private) && (private) == LLL_PRIVATE) \ - __asm __volatile (__lll_lock_asm_start \ - "1:\tlea %2, %%" RDI_LP "\n" \ - "2:\tsub $128, %%" RSP_LP "\n" \ - ".cfi_adjust_cfa_offset 128\n" \ - "3:\tcallq __lll_lock_wait_private\n" \ - "4:\tadd $128, %%" RSP_LP "\n" \ - ".cfi_adjust_cfa_offset -128\n" \ - "24:" \ - : "=S" (ignore1), "=&D" (ignore2), "=m" (futex), \ - "=a" (ignore3) \ - : "0" (1), "m" (futex), "3" (0) \ - : "cx", "r11", "cc", "memory"); \ - else \ - __asm __volatile (__lll_lock_asm_start \ - "1:\tlea %2, %%" RDI_LP "\n" \ - "2:\tsub $128, %%" RSP_LP "\n" \ - ".cfi_adjust_cfa_offset 128\n" \ - "3:\tcallq __lll_lock_wait\n" \ - "4:\tadd $128, %%" RSP_LP "\n" \ - ".cfi_adjust_cfa_offset -128\n" \ - "24:" \ - : "=S" (ignore1), "=D" (ignore2), "=m" (futex), \ - "=a" (ignore3) \ - : "1" (1), "m" (futex), "3" (0), "0" (private) \ - : "cx", "r11", "cc", "memory"); \ - }) \ - -#define lll_cond_lock(futex, private) \ - (void) \ - ({ int ignore1, ignore2, ignore3; \ - __asm __volatile (LOCK_INSTR "cmpxchgl %4, %2\n\t" \ - "jz 24f\n" \ - "1:\tlea %2, %%" RDI_LP "\n" \ - "2:\tsub $128, %%" RSP_LP "\n" \ - ".cfi_adjust_cfa_offset 128\n" \ - "3:\tcallq __lll_lock_wait\n" \ - "4:\tadd $128, %%" RSP_LP "\n" \ - ".cfi_adjust_cfa_offset -128\n" \ - "24:" \ - : "=S" (ignore1), "=D" (ignore2), "=m" (futex), \ - "=a" (ignore3) \ - : "1" (2), "m" (futex), "3" (0), "0" (private) \ - : "cx", "r11", "cc", "memory"); \ - }) - -#define lll_timedlock(futex, timeout, private) \ - ({ int result, ignore1, ignore2, ignore3; \ - __asm __volatile (LOCK_INSTR "cmpxchgl %1, %4\n\t" \ - "jz 24f\n" \ - "1:\tlea %4, %%" RDI_LP "\n" \ - "0:\tmov %8, %%" RDX_LP "\n" \ - "2:\tsub $128, %%" RSP_LP "\n" \ - ".cfi_adjust_cfa_offset 128\n" \ - "3:\tcallq __lll_timedlock_wait\n" \ - "4:\tadd $128, %%" RSP_LP "\n" \ - ".cfi_adjust_cfa_offset -128\n" \ - "24:" \ - : "=a" (result), "=D" (ignore1), "=S" (ignore2), \ - "=&d" (ignore3), "=m" (futex) \ - : "0" (0), "1" (1), "m" (futex), "m" (timeout), \ - "2" (private) \ - : "memory", "cx", "cc", "r10", "r11"); \ - result; }) - -extern int __lll_timedlock_elision (int *futex, short *adapt_count, - const struct timespec *timeout, - int private) attribute_hidden; - -#define lll_timedlock_elision(futex, adapt_count, timeout, private) \ - __lll_timedlock_elision(&(futex), &(adapt_count), timeout, private) - -#if !IS_IN (libc) || defined UP -# define __lll_unlock_asm_start LOCK_INSTR "decl %0\n\t" \ - "je 24f\n\t" -#else -# define __lll_unlock_asm_start "cmpl $0, __libc_multiple_threads(%%rip)\n\t" \ - "je 0f\n\t" \ - "lock; decl %0\n\t" \ - "jne 1f\n\t" \ - "jmp 24f\n\t" \ - "0:\tdecl %0\n\t" \ - "je 24f\n\t" -#endif - -#define lll_unlock(futex, private) \ - (void) \ - ({ int ignore; \ - if (__builtin_constant_p (private) && (private) == LLL_PRIVATE) \ - __asm __volatile (__lll_unlock_asm_start \ - "1:\tlea %0, %%" RDI_LP "\n" \ - "2:\tsub $128, %%" RSP_LP "\n" \ - ".cfi_adjust_cfa_offset 128\n" \ - "3:\tcallq __lll_unlock_wake_private\n" \ - "4:\tadd $128, %%" RSP_LP "\n" \ - ".cfi_adjust_cfa_offset -128\n" \ - "24:" \ - : "=m" (futex), "=&D" (ignore) \ - : "m" (futex) \ - : "ax", "cx", "r11", "cc", "memory"); \ - else \ - __asm __volatile (__lll_unlock_asm_start \ - "1:\tlea %0, %%" RDI_LP "\n" \ - "2:\tsub $128, %%" RSP_LP "\n" \ - ".cfi_adjust_cfa_offset 128\n" \ - "3:\tcallq __lll_unlock_wake\n" \ - "4:\tadd $128, %%" RSP_LP "\n" \ - ".cfi_adjust_cfa_offset -128\n" \ - "24:" \ - : "=m" (futex), "=&D" (ignore) \ - : "m" (futex), "S" (private) \ - : "ax", "cx", "r11", "cc", "memory"); \ - }) - -#define lll_islocked(futex) \ - (futex != LLL_LOCK_INITIALIZER) - -extern int __lll_lock_elision (int *futex, short *adapt_count, int private) - attribute_hidden; - -extern int __lll_unlock_elision (int *lock, int private) - attribute_hidden; - -extern int __lll_trylock_elision (int *lock, short *adapt_count) - attribute_hidden; - -#define lll_lock_elision(futex, adapt_count, private) \ - __lll_lock_elision (&(futex), &(adapt_count), private) -#define lll_unlock_elision(futex, adapt_count, private) \ - __lll_unlock_elision (&(futex), private) -#define lll_trylock_elision(futex, adapt_count) \ - __lll_trylock_elision (&(futex), &(adapt_count)) - -#endif /* !__ASSEMBLER__ */ - -#endif /* lowlevellock.h */ |