diff options
Diffstat (limited to 'sysdeps/unix/sysv/linux/i386/lowlevellock.h')
| -rw-r--r-- | sysdeps/unix/sysv/linux/i386/lowlevellock.h | 130 |
1 files changed, 20 insertions, 110 deletions
diff --git a/sysdeps/unix/sysv/linux/i386/lowlevellock.h b/sysdeps/unix/sysv/linux/i386/lowlevellock.h index 1032f4b666..c3528a8830 100644 --- a/sysdeps/unix/sysv/linux/i386/lowlevellock.h +++ b/sysdeps/unix/sysv/linux/i386/lowlevellock.h @@ -45,57 +45,10 @@ # endif #endif +#include <lowlevellock-futex.h> + +/* XXX Remove when no assembler code uses futexes anymore. */ #define SYS_futex 240 -#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 - - -#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 %%gs:%P1, %0" : "+r" (__fl) \ - : "i" (offsetof (struct pthread, header.private_futex))); \ - __fl | (fl); })) -# endif -#endif #ifndef __ASSEMBLER__ @@ -126,43 +79,6 @@ /* 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) \ - ({ \ - int __status; \ - register __typeof (val) _val asm ("edx") = (val); \ - __asm __volatile (LLL_EBX_LOAD \ - LLL_ENTER_KERNEL \ - LLL_EBX_LOAD \ - : "=a" (__status) \ - : "0" (SYS_futex), LLL_EBX_REG (futex), "S" (timeout), \ - "c" (__lll_private_flag (FUTEX_WAIT, private)), \ - "d" (_val), "i" (offsetof (tcbhead_t, sysinfo)) \ - : "memory"); \ - __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 (LLL_EBX_LOAD \ - LLL_ENTER_KERNEL \ - LLL_EBX_LOAD \ - : "=a" (__status) \ - : "0" (SYS_futex), LLL_EBX_REG (futex), \ - "c" (__lll_private_flag (FUTEX_WAKE, private)), \ - "d" (_nr), \ - "i" (0) /* phony, to align next arg's number */, \ - "i" (offsetof (tcbhead_t, sysinfo))); \ - __status; \ - }) - /* NB: in the lll_trylock macro we simply return the value in %eax after the cmpxchg instruction. In case the operation succeded this @@ -381,43 +297,37 @@ extern int __lll_timedlock_elision (int *futex, short *adapt_count, (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 (LLL_EBX_LOAD \ - "1:\tmovl %1, %%eax\n\t" \ - LLL_ENTER_KERNEL \ - "cmpl $0, (%%ebx)\n\t" \ - "jne 1b\n\t" \ - LLL_EBX_LOAD \ - : "=&a" (__ignore) \ - : "i" (SYS_futex), LLL_EBX_REG (&tid), "S" (0), \ - "c" (FUTEX_WAIT), "d" (_tid), \ - "i" (offsetof (tcbhead_t, sysinfo)) \ - : "memory"); \ + 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) __attribute__ ((regparm (2))) 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; }) + extern int __lll_lock_elision (int *futex, short *adapt_count, int private) attribute_hidden; |