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Use generic lowlevellock-futex.h in x86_64 lowlevellock.h.

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This commit is contained in:
Torvald Riegel
2014-12-17 18:55:19 +01:00
parent 6b814909b4
commit 76f71081cd
3 changed files with 40 additions and 120 deletions
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16
ChangeLog
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@@ -1,3 +1,19 @@
2014-12-19 Torvald Riegel <triegel@redhat.com>
* sysdeps/unix/sysv/linux/x86_64/lowlevellock.h: Include
<lowlevellock-futex.h>. Remove FUTEX_* constants defined there.
(__lll_private_flag): Remove.
(lll_futex_wait): Likewise.
(lll_futex_timed_wait): Likewise.
(lll_futex_wake): Likewise.
(lll_futex_requeue): Likewise.
(lll_wait_tid): Use lll_futex_wait instead of assembly code.
(__lll_timedwait_tid): Spell out argument names.
(lll_timedwait_tid): Add comments and parentheses around macro
arguments.
* sysdeps/unix/sysv/linux/lowlevellock-futex.h: Make FUTEX_* constants,
LLL_SHARED and LLL_PRIVATE usable from assembly code.
2014-12-19 Torvald Riegel <triegel@redhat.com>
* sysdeps/unix/sysv/linux/sh/libc-lowlevellock.S: Remove file.

5
sysdeps/unix/sysv/linux/lowlevellock-futex.h
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@@ -19,10 +19,11 @@
#ifndef _LOWLEVELLOCK_FUTEX_H
#define _LOWLEVELLOCK_FUTEX_H 1
#ifndef __ASSEMBLER__
#include <sysdep.h>
#include <tls.h>
#include <kernel-features.h>
#endif
#define FUTEX_WAIT 0
#define FUTEX_WAKE 1
@@ -48,6 +49,7 @@
#define LLL_PRIVATE 0
#define LLL_SHARED FUTEX_PRIVATE_FLAG
#ifndef __ASSEMBLER__
#if IS_IN (libc) || IS_IN (rtld)
/* In libc.so or ld.so all futexes are private. */
@@ -133,5 +135,6 @@
private), \
nr_wake, nr_move, mutex, val)
#endif /* !__ASSEMBLER__ */
#endif /* lowlevellock-futex.h */

139
sysdeps/unix/sysv/linux/x86_64/lowlevellock.h
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@@ -45,59 +45,13 @@
# endif
#endif
#include <lowlevellock-futex.h>
/* XXX Remove when no assembler code uses futexes anymore. */
#define SYS_futex __NR_futex
#define FUTEX_WAIT 0
#define FUTEX_WAKE 1
#define FUTEX_CMP_REQUEUE 4
#define FUTEX_WAKE_OP 5
#define FUTEX_LOCK_PI 6
#define FUTEX_UNLOCK_PI 7
#define FUTEX_TRYLOCK_PI 8
#define FUTEX_WAIT_BITSET 9
#define FUTEX_WAKE_BITSET 10
#define FUTEX_WAIT_REQUEUE_PI 11
#define FUTEX_CMP_REQUEUE_PI 12
#define FUTEX_PRIVATE_FLAG 128
#define FUTEX_CLOCK_REALTIME 256
#define FUTEX_BITSET_MATCH_ANY 0xffffffff
#define FUTEX_OP_CLEAR_WAKE_IF_GT_ONE ((4 << 24) | 1)
/* Values for 'private' parameter of locking macros. Yes, the
definition seems to be backwards. But it is not. The bit will be
reversed before passing to the system call. */
#define LLL_PRIVATE 0
#define LLL_SHARED FUTEX_PRIVATE_FLAG
#ifndef __ASSEMBLER__
#if IS_IN (libc) || IS_IN (rtld)
/* In libc.so or ld.so all futexes are private. */
# ifdef __ASSUME_PRIVATE_FUTEX
# define __lll_private_flag(fl, private) \
((fl) | FUTEX_PRIVATE_FLAG)
# else
# define __lll_private_flag(fl, private) \
((fl) | THREAD_GETMEM (THREAD_SELF, header.private_futex))
# endif
#else
# ifdef __ASSUME_PRIVATE_FUTEX
# define __lll_private_flag(fl, private) \
(((fl) | FUTEX_PRIVATE_FLAG) ^ (private))
# else
# define __lll_private_flag(fl, private) \
(__builtin_constant_p (private) \
? ((private) == 0 \
? ((fl) | THREAD_GETMEM (THREAD_SELF, header.private_futex)) \
: (fl)) \
: ({ unsigned int __fl = ((private) ^ FUTEX_PRIVATE_FLAG); \
asm ("andl %%fs:%P1, %0" : "+r" (__fl) \
: "i" (offsetof (struct pthread, header.private_futex))); \
__fl | (fl); }))
# endif
#endif
/* Initializer for lock. */
#define LLL_LOCK_INITIALIZER (0)
#define LLL_LOCK_INITIALIZER_LOCKED (1)
@@ -106,39 +60,6 @@
/* Delay in spinlock loop. */
#define BUSY_WAIT_NOP asm ("rep; nop")
#define lll_futex_wait(futex, val, private) \
lll_futex_timed_wait(futex, val, NULL, private)
#define lll_futex_timed_wait(futex, val, timeout, private) \
({ \
register const struct timespec *__to __asm ("r10") = timeout; \
int __status; \
register __typeof (val) _val __asm ("edx") = (val); \
__asm __volatile ("syscall" \
: "=a" (__status) \
: "0" (SYS_futex), "D" (futex), \
"S" (__lll_private_flag (FUTEX_WAIT, private)), \
"d" (_val), "r" (__to) \
: "memory", "cc", "r11", "cx"); \
__status; \
})
#define lll_futex_wake(futex, nr, private) \
({ \
int __status; \
register __typeof (nr) _nr __asm ("edx") = (nr); \
LIBC_PROBE (lll_futex_wake, 3, futex, nr, private); \
__asm __volatile ("syscall" \
: "=a" (__status) \
: "0" (SYS_futex), "D" (futex), \
"S" (__lll_private_flag (FUTEX_WAKE, private)), \
"d" (_nr) \
: "memory", "cc", "r10", "r11", "cx"); \
__status; \
})
/* NB: in the lll_trylock macro we simply return the value in %eax
after the cmpxchg instruction. In case the operation succeded this
@@ -378,58 +299,38 @@ extern int __lll_timedlock_elision (int *futex, short *adapt_count,
} \
while (0)
/* Returns non-zero if error happened, zero if success. */
#define lll_futex_requeue(ftx, nr_wake, nr_move, mutex, val, private) \
({ int __res; \
register int __nr_move __asm ("r10") = nr_move; \
register void *__mutex __asm ("r8") = mutex; \
register int __val __asm ("r9") = val; \
__asm __volatile ("syscall" \
: "=a" (__res) \
: "0" (__NR_futex), "D" ((void *) ftx), \
"S" (__lll_private_flag (FUTEX_CMP_REQUEUE, \
private)), "d" (nr_wake), \
"r" (__nr_move), "r" (__mutex), "r" (__val) \
: "cx", "r11", "cc", "memory"); \
__res < 0; })
#define lll_islocked(futex) \
(futex != LLL_LOCK_INITIALIZER)
/* The kernel notifies a process which uses CLONE_CHILD_CLEARTID via futex
wakeup when the clone terminates. The memory location contains the
thread ID while the clone is running and is reset to zero
afterwards.
The macro parameter must not have any side effect. */
wake-up when the clone terminates. The memory location contains the
thread ID while the clone is running and is reset to zero by the kernel
afterwards. The kernel up to version 3.16.3 does not use the private futex
operations for futex wake-up when the clone terminates. */
#define lll_wait_tid(tid) \
do { \
int __ignore; \
register __typeof (tid) _tid asm ("edx") = (tid); \
if (_tid != 0) \
__asm __volatile ("xorq %%r10, %%r10\n\t" \
"1:\tmovq %2, %%rax\n\t" \
"syscall\n\t" \
"cmpl $0, (%%rdi)\n\t" \
"jne 1b" \
: "=&a" (__ignore) \
: "S" (FUTEX_WAIT), "i" (SYS_futex), "D" (&tid), \
"d" (_tid) \
: "memory", "cc", "r10", "r11", "cx"); \
do { \
__typeof (tid) __tid; \
while ((__tid = (tid)) != 0) \
lll_futex_wait (&(tid), __tid, LLL_SHARED);\
} while (0)
extern int __lll_timedwait_tid (int *tid, const struct timespec *abstime)
extern int __lll_timedwait_tid (int *, const struct timespec *)
attribute_hidden;
/* As lll_wait_tid, but with a timeout. If the timeout occurs then return
ETIMEDOUT. If ABSTIME is invalid, return EINVAL.
XXX Note that this differs from the generic version in that we do the
error checking here and not in __lll_timedwait_tid. */
#define lll_timedwait_tid(tid, abstime) \
({ \
int __result = 0; \
if (tid != 0) \
if ((tid) != 0) \
{ \
if (abstime->tv_nsec < 0 || abstime->tv_nsec >= 1000000000) \
if ((abstime)->tv_nsec < 0 || (abstime)->tv_nsec >= 1000000000) \
__result = EINVAL; \
else \
__result = __lll_timedwait_tid (&tid, abstime); \
__result = __lll_timedwait_tid (&(tid), (abstime)); \
} \
__result; })