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Postgres FD Implementation
Commit 94e52d38 authored by Vadim B. Mikheev's avatar Vadim B. Mikheev
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src/include/storage/s_lock.h
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......@@ -7,411 +7,7 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/include/storage/s_lock.h,v 1.1 1997/09/18 14:20:59 momjian Exp $
*
*-------------------------------------------------------------------------
*/
/*
* DESCRIPTION
* The following code fragment should be written (in assembly
* language) on machines that have a native test-and-set instruction:
*
* void
* S_LOCK(char_address)
* char *char_address;
* {
* while (test_and_set(char_address))
* ;
* }
*
* If this is not done, POSTGRES will default to using System V
* semaphores (and take a large performance hit -- around 40% of
* its time on a DS5000/240 is spent in semop(3)...).
*
* NOTES
* AIX has a test-and-set but the recommended interface is the cs(3)
* system call. This provides an 8-instruction (plus system call
* overhead) uninterruptible compare-and-set operation. True
* spinlocks might be faster but using cs(3) still speeds up the
* regression test suite by about 25%. I don't have an assembler
* manual for POWER in any case.
*
*/
#ifndef S_LOCK_H
#define S_LOCK_H
#include "storage/ipc.h"
#if defined(HAS_TEST_AND_SET)
#if defined (nextstep)
/*
* NEXTSTEP (mach)
* slock_t is defined as a struct mutex.
*/
#define S_LOCK(lock) mutex_lock(lock)
#define S_UNLOCK(lock) mutex_unlock(lock)
#define S_INIT_LOCK(lock) mutex_init(lock)
/* S_LOCK_FREE should return 1 if lock is free; 0 if lock is locked */
/* For Mach, we have to delve inside the entrails of `struct mutex'. Ick! */
#define S_LOCK_FREE(alock) ((alock)->lock == 0)
#endif /* next */
#if defined(irix5)
/*
* SGI IRIX 5
* slock_t is defined as a struct abilock_t, which has a single unsigned long
* member.
*
* This stuff may be supplemented in the future with Masato Kataoka's MIPS-II
* assembly from his NECEWS SVR4 port, but we probably ought to retain this
* for the R3000 chips out there.
*/
#define S_LOCK(lock) do \
{ \
while (!acquire_lock(lock)) \
; \
} while (0)
#define S_UNLOCK(lock) release_lock(lock)
#define S_INIT_LOCK(lock) init_lock(lock)
/* S_LOCK_FREE should return 1 if lock is free; 0 if lock is locked */
#define S_LOCK_FREE(lock) (stat_lock(lock) == UNLOCKED)
#endif /* irix5 */
/*
* OSF/1 (Alpha AXP)
*
* Note that slock_t on the Alpha AXP is msemaphore instead of char
* (see storage/ipc.h).
*/
#if defined(__alpha__) || defined(__alpha)
#define S_LOCK(lock) do \
{ \
while (msem_lock((lock), MSEM_IF_NOWAIT) < 0) \
; \
} while (0)
#define S_UNLOCK(lock) msem_unlock((lock), 0)
#define S_INIT_LOCK(lock) msem_init((lock), MSEM_UNLOCKED)
#define S_LOCK_FREE(lock) (!(lock)->msem_state)
#endif /* alpha */
/*
* Solaris 2
*/
#if defined(i386_solaris) || \
defined(sparc_solaris)
/* for xxxxx_solaris, this is defined in port/.../tas.s */
static int tas(slock_t *lock);
#define S_LOCK(lock) do \
{ \
while (tas(lock)) \
; \
} while (0)
#define S_UNLOCK(lock) (*(lock) = 0)
#define S_INIT_LOCK(lock) S_UNLOCK(lock)
#endif /* i86pc_solaris || sparc_solaris */
/*
* AIX (POWER)
*
* Note that slock_t on POWER/POWER2/PowerPC is int instead of char
* (see storage/ipc.h).
*/
#if defined(aix)
#define S_LOCK(lock) do \
{ \
while (cs((int *) (lock), 0, 1)) \
; \
} while (0)
#define S_UNLOCK(lock) (*(lock) = 0)
#define S_INIT_LOCK(lock) S_UNLOCK(lock)
#endif /* aix */
/*
* HP-UX (PA-RISC)
*
* Note that slock_t on PA-RISC is a structure instead of char
* (see storage/ipc.h).
*/
#if defined(hpux)
/*
* a "set" slock_t has a single word cleared. a "clear" slock_t has
* all words set to non-zero.
*/
static slock_t clear_lock = {-1, -1, -1, -1};
static int tas(slock_t *lock);
#define S_LOCK(lock) do \
{ \
while (tas(lock)) \
; \
} while (0)
#define S_UNLOCK(lock) (*(lock) = clear_lock) /* struct assignment */
#define S_INIT_LOCK(lock) S_UNLOCK(lock)
#define S_LOCK_FREE(lock) ( *(int *) (((long) (lock) + 15) & ~15) != 0)
#endif /* hpux */
/*
* sun3
*/
#if defined(sun3)
static int tas(slock_t *lock);
#define S_LOCK(lock) do \
{ \
while (tas(lock)) \
; \
} while (0)
#define S_UNLOCK(lock) (*(lock) = 0)
#define S_INIT_LOCK(lock) S_UNLOCK(lock)
#ifdef NOT_USED
static int
tas_dummy()
{
asm("LLA0:");
asm(" .data");
asm(" .text");
asm("|#PROC# 04");
asm(" .globl _tas");
asm("_tas:");
asm("|#PROLOGUE# 1");
asm(" movel sp@(0x4),a0");
asm(" tas a0@");
asm(" beq LLA1");
asm(" moveq #-128,d0");
asm(" rts");
asm("LLA1:");
asm(" moveq #0,d0");
asm(" rts");
asm(" .data");
}
#endif
#endif /* sun3 */
/*
* sparc machines
*/
#if defined(NEED_SPARC_TAS_ASM)
/* if we're using -ansi w/ gcc, use __asm__ instead of asm */
#if defined(__STRICT_ANSI__)
#define asm(x) __asm__(x)
#endif
static int tas(slock_t *lock);
#ifdef NOT_USED
static int
tas_dummy()
{
asm(".seg \"data\"");
asm(".seg \"text\"");
asm(".global _tas");
asm("_tas:");
/*
* Sparc atomic test and set (sparc calls it "atomic load-store")
*/
asm("ldstub [%r8], %r8");
/*
* Did test and set actually do the set?
*/
asm("tst %r8");
asm("be,a ReturnZero");
/*
* otherwise, just return.
*/
asm("clr %r8");
asm("mov 0x1, %r8");
asm("ReturnZero:");
asm("retl");
asm("nop");
}
#endif
#define S_LOCK(addr) do \
{ \
while (tas(addr)) \
; \
} while (0)
/*
* addr should be as in the above S_LOCK routine
*/
#define S_UNLOCK(addr) (*(addr) = 0)
#define S_INIT_LOCK(addr) (*(addr) = 0)
#endif /* NEED_SPARC_TAS_ASM */
/*
* i386 based things
*/
#if defined(NEED_I386_TAS_ASM)
#define S_LOCK(lock) do \
{ \
slock_t res; \
do \
{ \
__asm__("xchgb %0,%1": "=q"(res), "=m"(*lock):"0"(0x1)); \
} while (res != 0); \
} while (0)
#define S_UNLOCK(lock) (*(lock) = 0)
#define S_INIT_LOCK(lock) S_UNLOCK(lock)
#endif /* NEED_I386_TAS_ASM */
#if defined(__alpha__) && defined(linux)
#define S_LOCK(lock) do \
{ \
slock_t res; \
do \
{ \
__asm__(" ldq $0, %0 \n\
bne $0, already_set \n\
ldq_l $0, %0 \n\
bne $0, already_set \n\
or $31, 1, $0 \n\
stq_c $0, %0 \n\
beq $0, stqc_fail \n\
success: bis $31, $31, %1 \n\
mb \n\
jmp $31, end \n\
stqc_fail: or $31, 1, $0 \n\
already_set: bis $0, $0, %1 \n\
end: nop ": "=m"(*lock), "=r"(res): :"0"); \
} while (res != 0); \
} while (0)
#define S_UNLOCK(lock) (__asm__("mb"), *(lock) = 0)
#define S_INIT_LOCK(lock) S_UNLOCK(lock)
#endif /* defined(__alpha__) && defined(linux) */
#if defined(linux) && defined(sparc)
#define S_LOCK(lock) do \
{ \
slock_t res; \
do \
{ \
__asm__("ldstub [%1], %0" \
: "=&r"(res) \
: "r"(lock)); \
} while (!res != 0); \
} while (0)
#define S_UNLOCK(lock) (*(lock) = 0)
#define S_INIT_LOCK(lock) S_UNLOCK(lock)
#endif /* defined(linux) && defined(sparc) */
#if defined(linux) && defined(PPC)
#ifdef NOT_USED
static int
tas_dummy()
{
__asm__(" \n\
tas: \n\
lwarx 5,0,3 \n\
cmpwi 5,0 \n\
bne fail \n\
addi 5,5,1 \n\
stwcx. 5,0,3 \n\
beq success \n\
fail: li 3,1 \n\
blr \n\
success: \n\
li 3,0 \n\
blr \n\
");
}
#endif
#define S_LOCK(lock) do \
{ \
while (tas(lock)) \
; \
} while (0)
#define S_UNLOCK(lock) (*(lock) = 0)
#define S_INIT_LOCK(lock) S_UNLOCK(lock)
#endif /* defined(linux) && defined(PPC) */
#endif /* HAS_TEST_AND_SET */
#endif /* S_LOCK_H */
/*-------------------------------------------------------------------------
*
* s_lock.h--
* This file contains the implementation (if any) for spinlocks.
*
* Copyright (c) 1994, Regents of the University of California
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/include/storage/s_lock.h,v 1.1 1997/09/18 14:20:59 momjian Exp $
* $Header: /cvsroot/pgsql/src/include/storage/s_lock.h,v 1.2 1997/09/22 04:21:51 vadim Exp $
*
*-------------------------------------------------------------------------
*/
......
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