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Significant cleanups in SysV IPC handling (shared mem and semaphores).

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IPC key assignment will now work correctly even when multiple postmasters
are using same logical port number (which is possible given -k switch).
There is only one shared-mem segment per postmaster now, not 3.
Rip out broken code for non-TAS case in bufmgr and xlog, substitute a
complete S_LOCK emulation using semaphores in spin.c.  TAS and non-TAS
logic is now exactly the same.
When deadlock is detected, "Deadlock detected" is now the elog(ERROR)
message, rather than a NOTICE that comes out before an unhelpful ERROR.
This commit is contained in:
Tom Lane
2000-11-28 23:27:57 +00:00
parent 914822713c
commit c715fdea26
27 changed files with 1172 additions and 1755 deletions
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26
src/include/storage/shmem.h
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@@ -7,7 +7,7 @@
* Portions Copyright (c) 1996-2000, PostgreSQL, Inc
* Portions Copyright (c) 1994, Regents of the University of California
*
* $Id: shmem.h,v 1.23 2000/06/28 03:33:27 tgl Exp $
* $Id: shmem.h,v 1.24 2000/11/28 23:27:57 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -18,17 +18,23 @@
#include "utils/hsearch.h"
/* The shared memory region can start at a different address
/*
* The shared memory region can start at a different address
* in every process. Shared memory "pointers" are actually
* offsets relative to the start of the shared memory region(s).
*
* In current usage, this is not actually a problem, but we keep
* the code that used to handle it...
*/
typedef unsigned long SHMEM_OFFSET;
#define INVALID_OFFSET (-1)
#define BAD_LOCATION (-1)
/* start of the lowest shared memory region. For now, assume that
* there is only one shared memory region
/*
* Start of the primary shared memory region, in this process' address space.
* The macros in this header file can only cope with offsets into this
* shared memory region!
*/
extern SHMEM_OFFSET ShmemBase;
@@ -39,14 +45,14 @@ extern SHMEM_OFFSET ShmemBase;
/* coerce a pointer into a shmem offset */
#define MAKE_OFFSET(xx_ptr)\
(SHMEM_OFFSET) (((unsigned long)(xx_ptr))-ShmemBase)
((SHMEM_OFFSET) (((unsigned long)(xx_ptr))-ShmemBase))
#define SHM_PTR_VALID(xx_ptr)\
(((unsigned long)xx_ptr) > ShmemBase)
(((unsigned long)(xx_ptr)) > ShmemBase)
/* cannot have an offset to ShmemFreeStart (offset 0) */
#define SHM_OFFSET_VALID(xx_offs)\
((xx_offs != 0) && (xx_offs != INVALID_OFFSET))
(((xx_offs) != 0) && ((xx_offs) != INVALID_OFFSET))
extern SPINLOCK ShmemLock;
@@ -60,11 +66,9 @@ typedef struct SHM_QUEUE
} SHM_QUEUE;
/* shmem.c */
extern void ShmemIndexReset(void);
extern void ShmemCreate(unsigned int key, unsigned int size);
extern int InitShmem(unsigned int key, unsigned int size);
extern void InitShmemAllocation(PGShmemHeader *seghdr);
extern void *ShmemAlloc(Size size);
extern int ShmemIsValid(unsigned long addr);
extern bool ShmemIsValid(unsigned long addr);
extern HTAB *ShmemInitHash(char *name, long init_size, long max_size,
HASHCTL *infoP, int hash_flags);
extern bool ShmemPIDLookup(int pid, SHMEM_OFFSET *locationPtr);