[6/9,v2] Alpha - Remove alpha lowlevellock.h
diff mbox

Message ID AA226F36-E351-4F7A-BA90-9009034CAA2A@linaro.org
State New
Headers show

Commit Message

Bernard Ogden June 10, 2014, 4:15 p.m. UTC
Great. Here's a patch to remove it instead.

I forgot to mention the changes this causes for alpha -

lll_futex_timed_wait_bitset now mainpulates its return value
through the usual macros - as callers do more than just compare
return value to 0, it may have been a bug that it was not doing
so before.
    
lll_futex_timed_wait_requeue_pi now calls INTERNAL_SYSCALL_ERROR_P
on the return value. This function only has one caller, and that
caller just compares return value to 0, so the behaviour is
equivalent.
    

2014-06-09  Bernard Ogden  <bernie.ogden@linaro.org>

	* sysdeps/unix/sysv/linux/alpha/lowlevellock.h: Remove file.


On 9 Jun 2014, at 21:39, Joseph S. Myers <joseph@codesourcery.com> wrote:

> On Mon, 9 Jun 2014, Bernard Ogden wrote:
> 
>> Simplify alpha lowlevellock.h
>> 
>> alpha's lowlevellock.h defines NR_futex, so we keep it but reduce
>> it to that define and an include-next to get the linux
>> lowlevellock.h.
> 
> But you don't need that definition.  glibc assumes at least 2.6.32 kernel 
> (headers and at runtime), and 2.6.32 headers define __NR_futex for alpha.  
> Such definitions of syscall numbers in glibc are mostly redundant 
> nowadays.  (nptl/sysdeps/i386/tls.h and 
> sysdeps/unix/sysv/linux/i386/clone.S are two more examples where such a 
> syscall number is defined, probably for convenience in building glibc when 
> the syscall was very new, but no longer need to be defined as long as the 
> files include the right headers.)
> 
> -- 
> Joseph S. Myers
> joseph@codesourcery.com

Comments

Richard Henderson June 11, 2014, 6:50 p.m. UTC | #1
On 06/10/2014 09:15 AM, Bernard Ogden wrote:
> Great. Here's a patch to remove it instead.
> 
> I forgot to mention the changes this causes for alpha -
> 
> lll_futex_timed_wait_bitset now mainpulates its return value
> through the usual macros - as callers do more than just compare
> return value to 0, it may have been a bug that it was not doing
> so before.

Yes, it looks like it.  It would have been returning a positive errno before,
as opposed to -errno that others return.

>     
> lll_futex_timed_wait_requeue_pi now calls INTERNAL_SYSCALL_ERROR_P
> on the return value. This function only has one caller, and that
> caller just compares return value to 0, so the behaviour is
> equivalent.

True.

> 	* sysdeps/unix/sysv/linux/alpha/lowlevellock.h: Remove file.

Ok.


r~

Patch
diff mbox

diff --git a/sysdeps/unix/sysv/linux/alpha/lowlevellock.h b/sysdeps/unix/sysv/linux/alpha/lowlevellock.h
deleted file mode 100644
index 361bd34..0000000
--- a/sysdeps/unix/sysv/linux/alpha/lowlevellock.h
+++ /dev/null
@@ -1,322 +0,0 @@ 
-/* Copyright (C) 2003-2014 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 _LOWLEVELLOCK_H
-#define _LOWLEVELLOCK_H	1
-
-#include <time.h>
-#include <sys/param.h>
-#include <bits/pthreadtypes.h>
-#include <atomic.h>
-#include <sysdep.h>
-#include <kernel-features.h>
-
-
-#define __NR_futex		394
-#define FUTEX_WAIT		0
-#define FUTEX_WAKE		1
-#define FUTEX_REQUEUE		3
-#define FUTEX_CMP_REQUEUE	4
-#define FUTEX_WAKE_OP		5
-#define FUTEX_OP_CLEAR_WAKE_IF_GT_ONE	((4 << 24) | 1)
-#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
-
-/* 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 !defined NOT_IN_libc || defined 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))								      \
-   : ((fl) | (((private) ^ FUTEX_PRIVATE_FLAG)				      \
-	      & THREAD_GETMEM (THREAD_SELF, header.private_futex))))
-# endif
-#endif
-
-
-#define lll_futex_wait(futexp, val, private) \
-  lll_futex_timed_wait (futexp, val, NULL, private)
-
-#define lll_futex_timed_wait_bitset(futexp, val, timespec, clockbit, private) \
-  ({									      \
-    INTERNAL_SYSCALL_DECL (__err);					      \
-    long int __ret;							      \
-    int __op = FUTEX_WAIT_BITSET | clockbit;				      \
-									      \
-    __ret = INTERNAL_SYSCALL (futex, __err, 6, (futexp),		      \
-			      __lll_private_flag (__op, private),	      \
-			      (val), (timespec), NULL /* Unused.  */, 	      \
-			      FUTEX_BITSET_MATCH_ANY);			      \
-    __ret;		      						      \
-  })
-
-#define lll_futex_timed_wait(futexp, val, timespec, private) \
-  ({									      \
-    INTERNAL_SYSCALL_DECL (__err);					      \
-    long int __ret;							      \
-    __ret = INTERNAL_SYSCALL (futex, __err, 4, (futexp),		      \
-			      __lll_private_flag (FUTEX_WAIT, private),	      \
-			      (val), (timespec));			      \
-    INTERNAL_SYSCALL_ERROR_P (__ret, __err)? -__ret : __ret;		      \
-  })
-
-#define lll_futex_wake(futexp, nr, private) \
-  ({									      \
-    INTERNAL_SYSCALL_DECL (__err);					      \
-    long int __ret;							      \
-    __ret = INTERNAL_SYSCALL (futex, __err, 4, (futexp),		      \
-			      __lll_private_flag (FUTEX_WAKE, private),	      \
-			      (nr), 0);					      \
-    INTERNAL_SYSCALL_ERROR_P (__ret, __err)? -__ret : __ret;		      \
-  })
-
-#define lll_robust_dead(futexv, private) \
-  do									      \
-    {									      \
-      int *__futexp = &(futexv);					      \
-      atomic_or (__futexp, FUTEX_OWNER_DIED);				      \
-      lll_futex_wake (__futexp, 1, private);				      \
-    }									      \
-  while (0)
-
-/* Returns non-zero if error happened, zero if success.  */
-#define lll_futex_requeue(futexp, nr_wake, nr_move, mutex, val, private) \
-  ({									      \
-    INTERNAL_SYSCALL_DECL (__err);					      \
-    long int __ret;							      \
-    __ret = INTERNAL_SYSCALL (futex, __err, 6, (futexp),		      \
-			      __lll_private_flag (FUTEX_CMP_REQUEUE, private),\
-			      (nr_wake), (nr_move), (mutex), (val));	      \
-    INTERNAL_SYSCALL_ERROR_P (__ret, __err);				      \
-  })
-
-/* Returns non-zero if error happened, zero if success.  */
-#define lll_futex_wake_unlock(futexp, nr_wake, nr_wake2, futexp2, private) \
-  ({									      \
-    INTERNAL_SYSCALL_DECL (__err);					      \
-    long int __ret;							      \
-    __ret = INTERNAL_SYSCALL (futex, __err, 6, (futexp),		      \
-			      __lll_private_flag (FUTEX_WAKE_OP, private),    \
-			      (nr_wake), (nr_wake2), (futexp2),		      \
-			      FUTEX_OP_CLEAR_WAKE_IF_GT_ONE);		      \
-    INTERNAL_SYSCALL_ERROR_P (__ret, __err);				      \
-  })
-
-/* Priority Inheritance support.  */
-#define lll_futex_wait_requeue_pi(futexp, val, mutex, private) \
-  lll_futex_timed_wait_requeue_pi (futexp, val, NULL, 0, mutex, private)
-
-#define lll_futex_timed_wait_requeue_pi(futexp, val, timespec, clockbit,      \
-					mutex, private)			      \
-  ({									      \
-    INTERNAL_SYSCALL_DECL (__err);					      \
-    int __op = FUTEX_WAIT_REQUEUE_PI | clockbit;			      \
-									      \
-    INTERNAL_SYSCALL (futex, __err, 5, (futexp),			      \
-		      __lll_private_flag (__op, private),		      \
-		      (val), (timespec), mutex); 			      \
-  })
-
-#define lll_futex_cmp_requeue_pi(futexp, nr_wake, nr_move, mutex, val, priv)  \
-  ({									      \
-    INTERNAL_SYSCALL_DECL (__err);					      \
-    long int __ret;							      \
-									      \
-    __ret = INTERNAL_SYSCALL (futex, __err, 6, (futexp),		      \
-			      __lll_private_flag (FUTEX_CMP_REQUEUE_PI, priv),\
-			      (nr_wake), (nr_move), (mutex), (val));	      \
-    INTERNAL_SYSCALL_ERROR_P (__ret, __err);				      \
-  })
-
-static inline int __attribute__((always_inline))
-__lll_trylock(int *futex)
-{
-  return atomic_compare_and_exchange_val_acq (futex, 1, 0) != 0;
-}
-#define lll_trylock(lock)	__lll_trylock (&(lock))
-
-
-static inline int __attribute__((always_inline))
-__lll_cond_trylock(int *futex)
-{
-  return atomic_compare_and_exchange_val_acq (futex, 2, 0) != 0;
-}
-#define lll_cond_trylock(lock)	__lll_cond_trylock (&(lock))
-
-
-static inline int __attribute__((always_inline))
-__lll_robust_trylock(int *futex, int id)
-{
-  return atomic_compare_and_exchange_val_acq (futex, id, 0) != 0;
-}
-#define lll_robust_trylock(lock, id) \
-  __lll_robust_trylock (&(lock), id)
-
-extern void __lll_lock_wait_private (int *futex) attribute_hidden;
-extern void __lll_lock_wait (int *futex, int private) attribute_hidden;
-extern int __lll_robust_lock_wait (int *futex, int private) attribute_hidden;
-
-static inline void __attribute__((always_inline))
-__lll_lock(int *futex, int private)
-{
-  if (atomic_compare_and_exchange_bool_acq (futex, 1, 0) != 0)
-    {
-      if (__builtin_constant_p (private) && private == LLL_PRIVATE)
-	__lll_lock_wait_private (futex);
-      else
-	__lll_lock_wait (futex, private);
-    }
-}
-#define lll_lock(futex, private) __lll_lock (&(futex), private)
-
-
-static inline int __attribute__ ((always_inline))
-__lll_robust_lock (int *futex, int id, int private)
-{
-  int result = 0;
-  if (atomic_compare_and_exchange_bool_acq (futex, id, 0) != 0)
-    result = __lll_robust_lock_wait (futex, private);
-  return result;
-}
-#define lll_robust_lock(futex, id, private) \
-  __lll_robust_lock (&(futex), id, private)
-
-
-static inline void __attribute__ ((always_inline))
-__lll_cond_lock (int *futex, int private)
-{
-  if (atomic_compare_and_exchange_bool_acq (futex, 2, 0) != 0)
-    __lll_lock_wait (futex, private);
-}
-#define lll_cond_lock(futex, private) __lll_cond_lock (&(futex), private)
-
-
-#define lll_robust_cond_lock(futex, id, private) \
-  __lll_robust_lock (&(futex), (id) | FUTEX_WAITERS, private)
-
-
-extern int __lll_timedlock_wait (int *futex, const struct timespec *,
-				 int private) attribute_hidden;
-extern int __lll_robust_timedlock_wait (int *futex, const struct timespec *,
-					int private) attribute_hidden;
-
-static inline int __attribute__ ((always_inline))
-__lll_timedlock (int *futex, const struct timespec *abstime, int private)
-{
-  int result = 0;
-  if (atomic_compare_and_exchange_bool_acq (futex, 1, 0) != 0)
-    result = __lll_timedlock_wait (futex, abstime, private);
-  return result;
-}
-#define lll_timedlock(futex, abstime, private) \
-  __lll_timedlock (&(futex), abstime, private)
-
-
-static inline int __attribute__ ((always_inline))
-__lll_robust_timedlock (int *futex, const struct timespec *abstime,
-			int id, int private)
-{
-  int result = 0;
-  if (atomic_compare_and_exchange_bool_acq (futex, id, 0) != 0)
-    result = __lll_robust_timedlock_wait (futex, abstime, private);
-  return result;
-}
-#define lll_robust_timedlock(futex, abstime, id, private) \
-  __lll_robust_timedlock (&(futex), abstime, id, private)
-
-
-#define __lll_unlock(futex, private) \
-  (void)							\
-    ({ int *__futex = (futex);					\
-       int __oldval = atomic_exchange_rel (__futex, 0);		\
-       if (__builtin_expect (__oldval > 1, 0))			\
-	 lll_futex_wake (__futex, 1, private);			\
-    })
-#define lll_unlock(futex, private) __lll_unlock(&(futex), private)
-
-
-#define __lll_robust_unlock(futex, private) \
-  (void)							\
-    ({ int *__futex = (futex);					\
-       int __oldval = atomic_exchange_rel (__futex, 0);		\
-       if (__builtin_expect (__oldval & FUTEX_WAITERS, 0))	\
-	 lll_futex_wake (__futex, 1, private);			\
-    })
-#define lll_robust_unlock(futex, private) \
-  __lll_robust_unlock(&(futex), private)
-
-
-#define lll_islocked(futex) \
-  (futex != 0)
-
-/* Initializers for lock.  */
-#define LLL_LOCK_INITIALIZER		(0)
-#define LLL_LOCK_INITIALIZER_LOCKED	(1)
-
-
-/* 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.	*/
-#define lll_wait_tid(tid) \
-  do {							\
-    __typeof (tid) __tid;				\
-    while ((__tid = (tid)) != 0)			\
-      lll_futex_wait (&(tid), __tid, LLL_SHARED);	\
-  } while (0)
-
-extern int __lll_timedwait_tid (int *, const struct timespec *)
-     attribute_hidden;
-
-#define lll_timedwait_tid(tid, abstime) \
-  ({							\
-    int __res = 0;					\
-    if ((tid) != 0)					\
-      __res = __lll_timedwait_tid (&(tid), (abstime));	\
-    __res;						\
-  })
-
-#endif	/* lowlevellock.h */