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[PATCH] s390: Use generic lowlevellock-futex.h.
- From: Torvald Riegel <triegel at redhat dot com>
- To: Stefan Liebler <stli at linux dot vnet dot ibm dot com>
- Cc: GLIBC Devel <libc-alpha at sourceware dot org>
- Date: Wed, 17 Dec 2014 23:59:32 +0100
- Subject: [PATCH] s390: Use generic lowlevellock-futex.h.
- Authentication-results: sourceware.org; auth=none
This untested patch removes the custom futex operations in s390
lowlevellock.h, and instead uses the generic ones from
lowlevellock-futex.h. They seem to be equivalent.
It also removes the definition of SYS_futex because it doesn't seem to
be used anywhere else.
It would be even nicer if we could remove the custom lowlevellock.h
altogether. However, current s390 has custom asm for the lock fast
paths, so this needs a closer review than I can do. Could you check
whether that would be possible?
Alternatively, I'd at least like to use generic futex operations. Could
you please review and test? Thanks!
2014-12-17 Torvald Riegel <triegel@redhat.com>
* sysdeps/unix/sysv/linux/s390/lowlevellock.h: Include
<lowlevellock-futex.h> and remove macros and functions that are now
defined there.
(SYS_futex): Remove.
commit 977d7402ba3fa0992c3a96ae6a629a0c564df891
Author: Torvald Riegel <triegel@redhat.com>
Date: Wed Dec 17 22:24:51 2014 +0100
s390: Use generic lowlevellock-futex.h.
diff --git a/sysdeps/unix/sysv/linux/s390/lowlevellock.h b/sysdeps/unix/sysv/linux/s390/lowlevellock.h
index 14fb4a8..f4dbd86 100644
--- a/sysdeps/unix/sysv/linux/s390/lowlevellock.h
+++ b/sysdeps/unix/sysv/linux/s390/lowlevellock.h
@@ -24,140 +24,8 @@
#include <bits/pthreadtypes.h>
#include <atomic.h>
#include <kernel-features.h>
+#include <lowlevellock-futex.h>
-#define SYS_futex 238
-#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 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)) \
- : ((fl) | (((private) ^ FUTEX_PRIVATE_FLAG) \
- & THREAD_GETMEM (THREAD_SELF, header.private_futex))))
-# endif
-#endif
-
-#define lll_futex_wait(futex, val, private) \
- lll_futex_timed_wait (futex, val, NULL, private)
-
-#define lll_futex_timed_wait(futexp, val, timespec, private) \
- ({ \
- INTERNAL_SYSCALL_DECL (__err); \
- \
- INTERNAL_SYSCALL (futex, __err, 4, (futexp), \
- __lll_private_flag (FUTEX_WAIT, private), \
- (val), (timespec)); \
- })
-
-#define lll_futex_timed_wait_bitset(futexp, val, timespec, clockbit, private) \
- ({ \
- INTERNAL_SYSCALL_DECL (__err); \
- int __op = FUTEX_WAIT_BITSET | clockbit; \
- \
- INTERNAL_SYSCALL (futex, __err, 6, (futexp), \
- __lll_private_flag (__op, private), \
- (val), (timespec), NULL /* Unused. */, \
- FUTEX_BITSET_MATCH_ANY); \
- })
-
-#define lll_futex_wake(futexp, nr, private) \
- ({ \
- INTERNAL_SYSCALL_DECL (__err); \
- \
- INTERNAL_SYSCALL (futex, __err, 4, (futexp), \
- __lll_private_flag (FUTEX_WAKE, private), \
- (nr), 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); \
- })
#define lll_compare_and_swap(futex, oldval, newval, operation) \
do { \