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dsm_impl.h File Reference
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Macros

#define DSM_IMPL_POSIX   1
 
#define DSM_IMPL_SYSV   2
 
#define DSM_IMPL_WINDOWS   3
 
#define DSM_IMPL_MMAP   4
 
#define USE_DSM_SYSV
 
#define DEFAULT_DYNAMIC_SHARED_MEMORY_TYPE   DSM_IMPL_SYSV
 
#define USE_DSM_MMAP
 
#define PG_DYNSHMEM_DIR   "pg_dynshmem"
 
#define PG_DYNSHMEM_MMAP_FILE_PREFIX   "mmap."
 

Typedefs

typedef uint32 dsm_handle
 

Enumerations

enum  dsm_op { DSM_OP_CREATE, DSM_OP_ATTACH, DSM_OP_DETACH, DSM_OP_DESTROY }
 

Functions

bool dsm_impl_op (dsm_op op, dsm_handle handle, Size request_size, void **impl_private, void **mapped_address, Size *mapped_size, int elevel)
 
void dsm_impl_pin_segment (dsm_handle handle, void *impl_private, void **impl_private_pm_handle)
 
void dsm_impl_unpin_segment (dsm_handle handle, void **impl_private)
 

Variables

int dynamic_shared_memory_type
 

Macro Definition Documentation

◆ DEFAULT_DYNAMIC_SHARED_MEMORY_TYPE

#define DEFAULT_DYNAMIC_SHARED_MEMORY_TYPE   DSM_IMPL_SYSV

Definition at line 36 of file dsm_impl.h.

◆ DSM_IMPL_MMAP

#define DSM_IMPL_MMAP   4

Definition at line 20 of file dsm_impl.h.

Referenced by dsm_impl_op(), and dsm_postmaster_startup().

◆ DSM_IMPL_POSIX

#define DSM_IMPL_POSIX   1

Definition at line 17 of file dsm_impl.h.

Referenced by dsm_impl_op().

◆ DSM_IMPL_SYSV

#define DSM_IMPL_SYSV   2

Definition at line 18 of file dsm_impl.h.

Referenced by dsm_impl_op().

◆ DSM_IMPL_WINDOWS

#define DSM_IMPL_WINDOWS   3

Definition at line 19 of file dsm_impl.h.

Referenced by dsm_impl_op(), dsm_impl_pin_segment(), and dsm_impl_unpin_segment().

◆ PG_DYNSHMEM_DIR

#define PG_DYNSHMEM_DIR   "pg_dynshmem"

Definition at line 50 of file dsm_impl.h.

Referenced by dsm_cleanup_for_mmap(), and dsm_impl_mmap().

◆ PG_DYNSHMEM_MMAP_FILE_PREFIX

#define PG_DYNSHMEM_MMAP_FILE_PREFIX   "mmap."

Definition at line 51 of file dsm_impl.h.

Referenced by dsm_cleanup_for_mmap(), and dsm_impl_mmap().

◆ USE_DSM_MMAP

#define USE_DSM_MMAP

Definition at line 38 of file dsm_impl.h.

◆ USE_DSM_SYSV

#define USE_DSM_SYSV

Definition at line 34 of file dsm_impl.h.

Typedef Documentation

◆ dsm_handle

typedef uint32 dsm_handle

Definition at line 54 of file dsm_impl.h.

Enumeration Type Documentation

◆ dsm_op

enum dsm_op
Enumerator
DSM_OP_CREATE 
DSM_OP_ATTACH 
DSM_OP_DETACH 
DSM_OP_DESTROY 

Definition at line 57 of file dsm_impl.h.

Function Documentation

◆ dsm_impl_op()

bool dsm_impl_op ( dsm_op  op,
dsm_handle  handle,
Size  request_size,
void **  impl_private,
void **  mapped_address,
Size mapped_size,
int  elevel 
)

Definition at line 158 of file dsm_impl.c.

References Assert, CHECK_FOR_INTERRUPTS, close, DSM_IMPL_MMAP, dsm_impl_mmap(), DSM_IMPL_POSIX, DSM_IMPL_SYSV, dsm_impl_sysv(), DSM_IMPL_WINDOWS, DSM_OP_ATTACH, DSM_OP_CREATE, DSM_OP_DESTROY, DSM_OP_DETACH, dynamic_shared_memory_type, EINTR, elevel, elog, ereport, errcode_for_dynamic_shared_memory(), errmsg(), ERROR, fd(), ftruncate, MAP_FAILED, MAP_HASSEMAPHORE, MAP_NOSYNC, name, PG_FILE_MODE_OWNER, ProcDiePending, QueryCancelPending, snprintf, and stat.

Referenced by dsm_attach(), dsm_backend_startup(), dsm_cleanup_using_control_segment(), dsm_create(), dsm_detach(), dsm_detach_all(), dsm_postmaster_shutdown(), dsm_postmaster_startup(), and dsm_unpin_segment().

161 {
162  Assert(op == DSM_OP_CREATE || request_size == 0);
163  Assert((op != DSM_OP_CREATE && op != DSM_OP_ATTACH) ||
164  (*mapped_address == NULL && *mapped_size == 0));
165 
167  {
168 #ifdef USE_DSM_POSIX
169  case DSM_IMPL_POSIX:
170  return dsm_impl_posix(op, handle, request_size, impl_private,
171  mapped_address, mapped_size, elevel);
172 #endif
173 #ifdef USE_DSM_SYSV
174  case DSM_IMPL_SYSV:
175  return dsm_impl_sysv(op, handle, request_size, impl_private,
176  mapped_address, mapped_size, elevel);
177 #endif
178 #ifdef USE_DSM_WINDOWS
179  case DSM_IMPL_WINDOWS:
180  return dsm_impl_windows(op, handle, request_size, impl_private,
181  mapped_address, mapped_size, elevel);
182 #endif
183 #ifdef USE_DSM_MMAP
184  case DSM_IMPL_MMAP:
185  return dsm_impl_mmap(op, handle, request_size, impl_private,
186  mapped_address, mapped_size, elevel);
187 #endif
188  default:
189  elog(ERROR, "unexpected dynamic shared memory type: %d",
191  return false;
192  }
193 }
#define DSM_IMPL_MMAP
Definition: dsm_impl.h:20
#define DSM_IMPL_SYSV
Definition: dsm_impl.h:18
#define DSM_IMPL_WINDOWS
Definition: dsm_impl.h:19
static bool dsm_impl_mmap(dsm_op op, dsm_handle handle, Size request_size, void **impl_private, void **mapped_address, Size *mapped_size, int elevel)
Definition: dsm_impl.c:772
#define ERROR
Definition: elog.h:43
#define DSM_IMPL_POSIX
Definition: dsm_impl.h:17
int dynamic_shared_memory_type
Definition: dsm_impl.c:114
static int elevel
Definition: vacuumlazy.c:143
static bool dsm_impl_sysv(dsm_op op, dsm_handle handle, Size request_size, void **impl_private, void **mapped_address, Size *mapped_size, int elevel)
Definition: dsm_impl.c:403
#define Assert(condition)
Definition: c.h:733
#define elog(elevel,...)
Definition: elog.h:228

◆ dsm_impl_pin_segment()

void dsm_impl_pin_segment ( dsm_handle  handle,
void *  impl_private,
void **  impl_private_pm_handle 
)

Definition at line 943 of file dsm_impl.c.

References _dosmaperr(), DSM_IMPL_WINDOWS, dynamic_shared_memory_type, ereport, errcode_for_dynamic_shared_memory(), errmsg(), ERROR, name, SEGMENT_NAME_PREFIX, and snprintf.

Referenced by dsm_pin_segment().

945 {
947  {
948 #ifdef USE_DSM_WINDOWS
949  case DSM_IMPL_WINDOWS:
950  {
951  HANDLE hmap;
952 
953  if (!DuplicateHandle(GetCurrentProcess(), impl_private,
954  PostmasterHandle, &hmap, 0, FALSE,
955  DUPLICATE_SAME_ACCESS))
956  {
957  char name[64];
958 
959  snprintf(name, 64, "%s.%u", SEGMENT_NAME_PREFIX, handle);
960  _dosmaperr(GetLastError());
961  ereport(ERROR,
963  errmsg("could not duplicate handle for \"%s\": %m",
964  name)));
965  }
966 
967  /*
968  * Here, we remember the handle that we created in the
969  * postmaster process. This handle isn't actually usable in
970  * any process other than the postmaster, but that doesn't
971  * matter. We're just holding onto it so that, if the segment
972  * is unpinned, dsm_impl_unpin_segment can close it.
973  */
974  *impl_private_pm_handle = hmap;
975  break;
976  }
977 #endif
978  default:
979  break;
980  }
981 }
void _dosmaperr(unsigned long)
Definition: win32error.c:171
#define DSM_IMPL_WINDOWS
Definition: dsm_impl.h:19
static int errcode_for_dynamic_shared_memory(void)
Definition: dsm_impl.c:1025
#define ERROR
Definition: elog.h:43
#define SEGMENT_NAME_PREFIX
Definition: dsm_impl.c:119
int dynamic_shared_memory_type
Definition: dsm_impl.c:114
#define ereport(elevel, rest)
Definition: elog.h:141
const char * name
Definition: encode.c:521
int errmsg(const char *fmt,...)
Definition: elog.c:822
#define snprintf
Definition: port.h:192

◆ dsm_impl_unpin_segment()

void dsm_impl_unpin_segment ( dsm_handle  handle,
void **  impl_private 
)

Definition at line 993 of file dsm_impl.c.

References _dosmaperr(), DSM_IMPL_WINDOWS, dynamic_shared_memory_type, ereport, errcode_for_dynamic_shared_memory(), errmsg(), ERROR, name, SEGMENT_NAME_PREFIX, and snprintf.

Referenced by dsm_unpin_segment().

994 {
996  {
997 #ifdef USE_DSM_WINDOWS
998  case DSM_IMPL_WINDOWS:
999  {
1000  if (*impl_private &&
1001  !DuplicateHandle(PostmasterHandle, *impl_private,
1002  NULL, NULL, 0, FALSE,
1003  DUPLICATE_CLOSE_SOURCE))
1004  {
1005  char name[64];
1006 
1007  snprintf(name, 64, "%s.%u", SEGMENT_NAME_PREFIX, handle);
1008  _dosmaperr(GetLastError());
1009  ereport(ERROR,
1011  errmsg("could not duplicate handle for \"%s\": %m",
1012  name)));
1013  }
1014 
1015  *impl_private = NULL;
1016  break;
1017  }
1018 #endif
1019  default:
1020  break;
1021  }
1022 }
void _dosmaperr(unsigned long)
Definition: win32error.c:171
#define DSM_IMPL_WINDOWS
Definition: dsm_impl.h:19
static int errcode_for_dynamic_shared_memory(void)
Definition: dsm_impl.c:1025
#define ERROR
Definition: elog.h:43
#define SEGMENT_NAME_PREFIX
Definition: dsm_impl.c:119
int dynamic_shared_memory_type
Definition: dsm_impl.c:114
#define ereport(elevel, rest)
Definition: elog.h:141
const char * name
Definition: encode.c:521
int errmsg(const char *fmt,...)
Definition: elog.c:822
#define snprintf
Definition: port.h:192

Variable Documentation

◆ dynamic_shared_memory_type

int dynamic_shared_memory_type