#include "postgres.h"
#include "access/transam.h"
#include "fmgr.h"
#include "funcapi.h"
#include "miscadmin.h"
#include "storage/lwlock.h"
#include "storage/pg_shmem.h"
#include "storage/shmem.h"
#include "storage/spin.h"
#include "utils/builtins.h"

Include dependency graph for shmem.c:

Macros
#define	PG_GET_SHMEM_SIZES_COLS 4

Functions
static void *	ShmemAllocRaw (Size size, Size *allocated_size)

void	InitShmemAccess (void *seghdr)

void	InitShmemAllocation (void)

void *	ShmemAlloc (Size size)

void *	ShmemAllocNoError (Size size)

void *	ShmemAllocUnlocked (Size size)

bool	ShmemAddrIsValid (const void *addr)

void	InitShmemIndex (void)

HTAB *	ShmemInitHash (const char name, long init_size, long max_size, HASHCTL infoP, int hash_flags)

void *	ShmemInitStruct (const char name, Size size, bool foundPtr)

Size	add_size (Size s1, Size s2)

Size	mul_size (Size s1, Size s2)

Datum	pg_get_shmem_allocations (PG_FUNCTION_ARGS)

Variables
static PGShmemHeader *	ShmemSegHdr

static void *	ShmemBase

static void *	ShmemEnd

slock_t *	ShmemLock

static HTAB *	ShmemIndex = NULL

Macro Definition Documentation

◆ PG_GET_SHMEM_SIZES_COLS

#define PG_GET_SHMEM_SIZES_COLS 4

Referenced by pg_get_shmem_allocations().

Function Documentation

◆ add_size()

Size add_size	(	Size	s1,
		Size	s2
	)

Definition at line 498 of file shmem.c.

References ereport, errcode(), errmsg(), ERROR, and s2.

Referenced by _bt_parallel_estimate_shared(), ApplyLauncherShmemSize(), AsyncShmemInit(), AsyncShmemSize(), AutoVacuumShmemSize(), BackendStatusShmemSize(), BackgroundWorkerShmemSize(), BTreeShmemSize(), BufferShmemSize(), CheckpointerShmemSize(), CreateSharedMemoryAndSemaphores(), CreateSharedProcArray(), estimate_variable_size(), EstimateComboCIDStateSpace(), EstimateGUCStateSpace(), EstimateLibraryStateSpace(), EstimateParamExecSpace(), EstimateParamListSpace(), EstimateSnapshotSpace(), EstimateTransactionStateSpace(), ExecAppendEstimate(), ExecBitmapHeapEstimate(), ExecHashEstimate(), ExecSortEstimate(), expand_planner_arrays(), hash_estimate_size(), index_parallelscan_estimate(), index_parallelscan_initialize(), LockShmemSize(), LWLockShmemSize(), MultiXactShmemSize(), pgss_memsize(), PMSignalShmemSize(), PredicateLockShmemSize(), ProcArrayShmemSize(), ProcGlobalShmemSize(), ProcSignalShmemSize(), ReplicationOriginShmemSize(), ReplicationSlotsShmemSize(), RequestAddinShmemSpace(), SerializeTransactionState(), shm_toc_estimate(), SInvalShmemSize(), SnapMgrShmemSize(), StrategyShmemSize(), table_parallelscan_estimate(), tuplesort_estimate_shared(), TwoPhaseShmemSize(), WalRcvShmemSize(), WalSndShmemSize(), and XLOGShmemSize().

 {
     Size        result;
 
     result = s1 + s2;
     /* We are assuming Size is an unsigned type here... */
     if (result < s1 || result < s2)
         ereport(ERROR,
                 (errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
                  errmsg("requested shared memory size overflows size_t")));
     return result;
 }

◆ InitShmemAccess()

void InitShmemAccess ( void * seghdr )

Definition at line 101 of file shmem.c.

References ShmemBase, ShmemEnd, and PGShmemHeader::totalsize.

Referenced by BackendRun(), and CreateSharedMemoryAndSemaphores().

 {
     PGShmemHeader *shmhdr = (PGShmemHeader *) seghdr;
 
     ShmemSegHdr = shmhdr;
     ShmemBase = (void *) shmhdr;
     ShmemEnd = (char *) ShmemBase + shmhdr->totalsize;
 }

◆ InitShmemAllocation()

void InitShmemAllocation ( void )

Definition at line 116 of file shmem.c.

References Assert, CACHELINEALIGN, ShmemAlloc(), ShmemAllocUnlocked(), ShmemLock, ShmemSegHdr, ShmemVariableCache, and SpinLockInit.

Referenced by CreateSharedMemoryAndSemaphores().

 {
     PGShmemHeader *shmhdr = ShmemSegHdr;
     char       *aligned;
 
     Assert(shmhdr != NULL);
 
     /*
      * Initialize the spinlock used by ShmemAlloc.  We must use
      * ShmemAllocUnlocked, since obviously ShmemAlloc can't be called yet.
      */
     ShmemLock = (slock_t *) ShmemAllocUnlocked(sizeof(slock_t));
 
     SpinLockInit(ShmemLock);
 
     /*
      * Allocations after this point should go through ShmemAlloc, which
      * expects to allocate everything on cache line boundaries.  Make sure the
      * first allocation begins on a cache line boundary.
      */
     aligned = (char *)
         (CACHELINEALIGN((((char *) shmhdr) + shmhdr->freeoffset)));
     shmhdr->freeoffset = aligned - (char *) shmhdr;
 
     /* ShmemIndex can't be set up yet (need LWLocks first) */
     shmhdr->index = NULL;
     ShmemIndex = (HTAB *) NULL;
 
     /*
      * Initialize ShmemVariableCache for transaction manager. (This doesn't
      * really belong here, but not worth moving.)
      */
     ShmemVariableCache = (VariableCache)
         ShmemAlloc(sizeof(*ShmemVariableCache));
     memset(ShmemVariableCache, 0, sizeof(*ShmemVariableCache));
 }

◆ InitShmemIndex()

void InitShmemIndex ( void )

Definition at line 292 of file shmem.c.

References HASHCTL::entrysize, HASH_ELEM, HASHCTL::keysize, SHMEM_INDEX_KEYSIZE, SHMEM_INDEX_SIZE, and ShmemInitHash().

Referenced by CreateSharedMemoryAndSemaphores().

 {
     HASHCTL     info;
     int         hash_flags;
 
     /*
      * Create the shared memory shmem index.
      *
      * Since ShmemInitHash calls ShmemInitStruct, which expects the ShmemIndex
      * hashtable to exist already, we have a bit of a circularity problem in
      * initializing the ShmemIndex itself.  The special "ShmemIndex" hash
      * table name will tell ShmemInitStruct to fake it.
      */
     info.keysize = SHMEM_INDEX_KEYSIZE;
     info.entrysize = sizeof(ShmemIndexEnt);
     hash_flags = HASH_ELEM;
 
     ShmemIndex = ShmemInitHash("ShmemIndex",
                                SHMEM_INDEX_SIZE, SHMEM_INDEX_SIZE,
                                &info, hash_flags);
 }

◆ mul_size()

Size mul_size	(	Size	s1,
		Size	s2
	)

Definition at line 515 of file shmem.c.

References ereport, errcode(), errmsg(), ERROR, and s2.

Referenced by ApplyLauncherShmemSize(), AsyncShmemInit(), AsyncShmemSize(), AutoVacuumShmemSize(), BackendStatusShmemSize(), BackgroundWorkerShmemSize(), BTreeShmemSize(), BufferShmemSize(), CheckpointerShmemSize(), CreateSharedBackendStatus(), CreateSharedProcArray(), EstimateComboCIDStateSpace(), EstimateReindexStateSpace(), EstimateSnapshotSpace(), EstimateTransactionStateSpace(), ExecHashEstimate(), ExecInitParallelPlan(), ExecParallelRetrieveInstrumentation(), ExecParallelRetrieveJitInstrumentation(), ExecParallelSetupTupleQueues(), ExecSortEstimate(), hash_estimate_size(), InitializeParallelDSM(), InitPredicateLocks(), LWLockShmemSize(), PGSemaphoreShmemSize(), PMSignalShmemSize(), PostmasterMarkPIDForWorkerNotify(), PredicateLockShmemSize(), ProcArrayShmemSize(), ProcGlobalShmemSize(), ProcSignalShmemSize(), ReplicationOriginShmemSize(), ReplicationSlotsShmemSize(), shm_toc_estimate(), SInvalShmemSize(), SnapMgrShmemSize(), tuplesort_estimate_shared(), TwoPhaseShmemSize(), WalSndShmemSize(), and XLOGShmemSize().

 {
     Size        result;
 
     if (s1 == 0 || s2 == 0)
         return 0;
     result = s1 * s2;
     /* We are assuming Size is an unsigned type here... */
     if (result / s2 != s1)
         ereport(ERROR,
                 (errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
                  errmsg("requested shared memory size overflows size_t")));
     return result;
 }

◆ pg_get_shmem_allocations()

Datum pg_get_shmem_allocations ( PG_FUNCTION_ARGS )

Definition at line 532 of file shmem.c.

References ReturnSetInfo::allowedModes, CStringGetTextDatum, ReturnSetInfo::econtext, ExprContext::ecxt_per_query_memory, elog, ereport, errcode(), errmsg(), ERROR, PGShmemHeader::freeoffset, get_call_result_type(), hash_seq_init(), hash_seq_search(), Int64GetDatum(), IsA, LW_SHARED, LWLockAcquire(), LWLockRelease(), MemoryContextSwitchTo(), PG_GET_SHMEM_SIZES_COLS, ReturnSetInfo::returnMode, ReturnSetInfo::setDesc, ReturnSetInfo::setResult, SFRM_Materialize, PGShmemHeader::totalsize, tuplestore_begin_heap(), tuplestore_donestoring, tuplestore_putvalues(), TYPEFUNC_COMPOSITE, values, and work_mem.

 {
 #define PG_GET_SHMEM_SIZES_COLS 4
     ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo;
     TupleDesc   tupdesc;
     Tuplestorestate *tupstore;
     MemoryContext per_query_ctx;
     MemoryContext oldcontext;
     HASH_SEQ_STATUS hstat;
     ShmemIndexEnt *ent;
     Size    named_allocated = 0;
     Datum       values[PG_GET_SHMEM_SIZES_COLS];
     bool        nulls[PG_GET_SHMEM_SIZES_COLS];
 
     /* check to see if caller supports us returning a tuplestore */
     if (rsinfo == NULL || !IsA(rsinfo, ReturnSetInfo))
         ereport(ERROR,
                 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
                  errmsg("set-valued function called in context that cannot accept a set")));
     if (!(rsinfo->allowedModes & SFRM_Materialize))
         ereport(ERROR,
                 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
                  errmsg("materialize mode required, but it is not allowed in this context")));
 
     /* Build a tuple descriptor for our result type */
     if (get_call_result_type(fcinfo, NULL, &tupdesc) != TYPEFUNC_COMPOSITE)
         elog(ERROR, "return type must be a row type");
 
     per_query_ctx = rsinfo->econtext->ecxt_per_query_memory;
     oldcontext = MemoryContextSwitchTo(per_query_ctx);
 
     tupstore = tuplestore_begin_heap(true, false, work_mem);
     rsinfo->returnMode = SFRM_Materialize;
     rsinfo->setResult = tupstore;
     rsinfo->setDesc = tupdesc;
 
     MemoryContextSwitchTo(oldcontext);
 
     LWLockAcquire(ShmemIndexLock, LW_SHARED);
 
     hash_seq_init(&hstat, ShmemIndex);
 
     /* output all allocated entries */
     memset(nulls, 0, sizeof(nulls));
     while ((ent = (ShmemIndexEnt *) hash_seq_search(&hstat)) != NULL)
     {
         values[0] = CStringGetTextDatum(ent->key);
         values[1] = Int64GetDatum((char *) ent->location - (char *) ShmemSegHdr);
         values[2] = Int64GetDatum(ent->size);
         values[3] = Int64GetDatum(ent->allocated_size);
         named_allocated += ent->allocated_size;
 
         tuplestore_putvalues(tupstore, tupdesc, values, nulls);
     }
 
     /* output shared memory allocated but not counted via the shmem index */
     values[0] = CStringGetTextDatum("<anonymous>");
     nulls[1] = true;
     values[2] = Int64GetDatum(ShmemSegHdr->freeoffset - named_allocated);
     values[3] = values[2];
     tuplestore_putvalues(tupstore, tupdesc, values, nulls);
 
     /* output as-of-yet unused shared memory */
     nulls[0] = true;
     values[1] = Int64GetDatum(ShmemSegHdr->freeoffset);
     nulls[1] = false;
     values[2] = Int64GetDatum(ShmemSegHdr->totalsize - ShmemSegHdr->freeoffset);
     values[3] = values[2];
     tuplestore_putvalues(tupstore, tupdesc, values, nulls);
 
     LWLockRelease(ShmemIndexLock);
 
     tuplestore_donestoring(tupstore);
 
     return (Datum) 0;
 }

◆ ShmemAddrIsValid()

bool ShmemAddrIsValid ( const void * addr )

Definition at line 283 of file shmem.c.

References ShmemBase, and ShmemEnd.

Referenced by NextPredXact(), ReleasePredXact(), ShmemInitStruct(), SHMQueueDelete(), SHMQueueElemInit(), SHMQueueEmpty(), SHMQueueInit(), SHMQueueInsertAfter(), SHMQueueInsertBefore(), SHMQueueIsDetached(), SHMQueueNext(), and SHMQueuePrev().

 {
     return (addr >= ShmemBase) && (addr < ShmemEnd);
 }

◆ ShmemAlloc()

void* ShmemAlloc ( Size size )

Definition at line 161 of file shmem.c.

References ereport, errcode(), errmsg(), ERROR, and ShmemAllocRaw().

Referenced by CreateLWLocks(), InitPredicateLocks(), InitProcGlobal(), InitShmemAllocation(), PostmasterMarkPIDForWorkerNotify(), and ShmemInitStruct().

 {
     void       *newSpace;
     Size        allocated_size;
 
     newSpace = ShmemAllocRaw(size, &allocated_size);
     if (!newSpace)
         ereport(ERROR,
                 (errcode(ERRCODE_OUT_OF_MEMORY),
                  errmsg("out of shared memory (%zu bytes requested)",
                         size)));
     return newSpace;
 }

◆ ShmemAllocNoError()

void* ShmemAllocNoError ( Size size )

Definition at line 181 of file shmem.c.

References ShmemAllocRaw().

Referenced by ShmemInitHash().

 {
     Size        allocated_size;
 
     return ShmemAllocRaw(size, &allocated_size);
 }

◆ ShmemAllocRaw()

static void * ShmemAllocRaw	(	Size	size,
		Size *	allocated_size
	)

static

Definition at line 195 of file shmem.c.

References Assert, CACHELINEALIGN, PGShmemHeader::freeoffset, ShmemBase, ShmemLock, SpinLockAcquire, and SpinLockRelease.

Referenced by ShmemAlloc(), ShmemAllocNoError(), and ShmemInitStruct().

 {
     Size        newStart;
     Size        newFree;
     void       *newSpace;
 
     /*
      * Ensure all space is adequately aligned.  We used to only MAXALIGN this
      * space but experience has proved that on modern systems that is not good
      * enough.  Many parts of the system are very sensitive to critical data
      * structures getting split across cache line boundaries.  To avoid that,
      * attempt to align the beginning of the allocation to a cache line
      * boundary.  The calling code will still need to be careful about how it
      * uses the allocated space - e.g. by padding each element in an array of
      * structures out to a power-of-two size - but without this, even that
      * won't be sufficient.
      */
     size = CACHELINEALIGN(size);
     *allocated_size = size;
 
     Assert(ShmemSegHdr != NULL);
 
     SpinLockAcquire(ShmemLock);
 
     newStart = ShmemSegHdr->freeoffset;
 
     newFree = newStart + size;
     if (newFree <= ShmemSegHdr->totalsize)
     {
         newSpace = (void *) ((char *) ShmemBase + newStart);
         ShmemSegHdr->freeoffset = newFree;
     }
     else
         newSpace = NULL;
 
     SpinLockRelease(ShmemLock);
 
     /* note this assert is okay with newSpace == NULL */
     Assert(newSpace == (void *) CACHELINEALIGN(newSpace));
 
     return newSpace;
 }

◆ ShmemAllocUnlocked()

void* ShmemAllocUnlocked ( Size size )

Definition at line 247 of file shmem.c.

References Assert, ereport, errcode(), errmsg(), ERROR, PGShmemHeader::freeoffset, MAXALIGN, ShmemBase, and PGShmemHeader::totalsize.

Referenced by InitShmemAllocation(), PGReserveSemaphores(), and SpinlockSemaInit().

 {
     Size        newStart;
     Size        newFree;
     void       *newSpace;
 
     /*
      * Ensure allocated space is adequately aligned.
      */
     size = MAXALIGN(size);
 
     Assert(ShmemSegHdr != NULL);
 
     newStart = ShmemSegHdr->freeoffset;
 
     newFree = newStart + size;
     if (newFree > ShmemSegHdr->totalsize)
         ereport(ERROR,
                 (errcode(ERRCODE_OUT_OF_MEMORY),
                  errmsg("out of shared memory (%zu bytes requested)",
                         size)));
     ShmemSegHdr->freeoffset = newFree;
 
     newSpace = (void *) ((char *) ShmemBase + newStart);
 
     Assert(newSpace == (void *) MAXALIGN(newSpace));
 
     return newSpace;
 }

◆ ShmemInitHash()

HTAB* ShmemInitHash	(	const char *	name,
		long	init_size,
		long	max_size,
		HASHCTL *	infoP,
		int	hash_flags
	)

Definition at line 337 of file shmem.c.

References HASHCTL::alloc, HASHCTL::dsize, HASH_ALLOC, HASH_ATTACH, hash_create(), HASH_DIRSIZE, hash_get_shared_size(), hash_select_dirsize(), HASH_SHARED_MEM, HASHCTL::hctl, HASHCTL::max_dsize, ShmemAllocNoError(), and ShmemInitStruct().

Referenced by InitBufTable(), InitLocks(), InitPredicateLocks(), InitShmemIndex(), and pgss_shmem_startup().

 {
     bool        found;
     void       *location;
 
     /*
      * Hash tables allocated in shared memory have a fixed directory; it can't
      * grow or other backends wouldn't be able to find it. So, make sure we
      * make it big enough to start with.
      *
      * The shared memory allocator must be specified too.
      */
     infoP->dsize = infoP->max_dsize = hash_select_dirsize(max_size);
     infoP->alloc = ShmemAllocNoError;
     hash_flags |= HASH_SHARED_MEM | HASH_ALLOC | HASH_DIRSIZE;
 
     /* look it up in the shmem index */
     location = ShmemInitStruct(name,
                                hash_get_shared_size(infoP, hash_flags),
                                &found);
 
     /*
      * if it already exists, attach to it rather than allocate and initialize
      * new space
      */
     if (found)
         hash_flags |= HASH_ATTACH;
 
     /* Pass location of hashtable header to hash_create */
     infoP->hctl = (HASHHDR *) location;
 
     return hash_create(name, init_size, infoP, hash_flags);
 }

◆ ShmemInitStruct()

void* ShmemInitStruct	(	const char *	name,
		Size	size,
		bool *	foundPtr
	)

Definition at line 392 of file shmem.c.

References ShmemIndexEnt::allocated_size, Assert, CACHELINEALIGN, ereport, errcode(), errmsg(), ERROR, HASH_ENTER_NULL, HASH_REMOVE, hash_search(), PGShmemHeader::index, IsUnderPostmaster, ShmemIndexEnt::location, LW_EXCLUSIVE, LWLockAcquire(), LWLockRelease(), ShmemAddrIsValid(), ShmemAlloc(), ShmemAllocRaw(), ShmemSegHdr, and ShmemIndexEnt::size.

Referenced by ApplyLauncherShmemInit(), apw_init_shmem(), AsyncShmemInit(), AutoVacuumShmemInit(), AuxiliaryPidGetProc(), BackgroundWorkerShmemInit(), BTreeShmemInit(), CheckpointerShmemInit(), CommitTsShmemInit(), CreateSharedBackendStatus(), CreateSharedInvalidationState(), CreateSharedProcArray(), InitBufferPool(), InitLocks(), InitPredicateLocks(), InitProcGlobal(), MultiXactShmemInit(), OldSerXidInit(), pgss_shmem_startup(), PMSignalShmemInit(), ProcSignalShmemInit(), ReplicationOriginShmemInit(), ReplicationSlotsShmemInit(), ShmemInitHash(), SimpleLruInit(), SnapMgrInit(), StrategyInitialize(), SyncScanShmemInit(), TwoPhaseShmemInit(), WalRcvShmemInit(), WalSndShmemInit(), and XLOGShmemInit().

 {
     ShmemIndexEnt *result;
     void       *structPtr;
 
     LWLockAcquire(ShmemIndexLock, LW_EXCLUSIVE);
 
     if (!ShmemIndex)
     {
         PGShmemHeader *shmemseghdr = ShmemSegHdr;
 
         /* Must be trying to create/attach to ShmemIndex itself */
         Assert(strcmp(name, "ShmemIndex") == 0);
 
         if (IsUnderPostmaster)
         {
             /* Must be initializing a (non-standalone) backend */
             Assert(shmemseghdr->index != NULL);
             structPtr = shmemseghdr->index;
             *foundPtr = true;
         }
         else
         {
             /*
              * If the shmem index doesn't exist, we are bootstrapping: we must
              * be trying to init the shmem index itself.
              *
              * Notice that the ShmemIndexLock is released before the shmem
              * index has been initialized.  This should be OK because no other
              * process can be accessing shared memory yet.
              */
             Assert(shmemseghdr->index == NULL);
             structPtr = ShmemAlloc(size);
             shmemseghdr->index = structPtr;
             *foundPtr = false;
         }
         LWLockRelease(ShmemIndexLock);
         return structPtr;
     }
 
     /* look it up in the shmem index */
     result = (ShmemIndexEnt *)
         hash_search(ShmemIndex, name, HASH_ENTER_NULL, foundPtr);
 
     if (!result)
     {
         LWLockRelease(ShmemIndexLock);
         ereport(ERROR,
                 (errcode(ERRCODE_OUT_OF_MEMORY),
                  errmsg("could not create ShmemIndex entry for data structure \"%s\"",
                         name)));
     }
 
     if (*foundPtr)
     {
         /*
          * Structure is in the shmem index so someone else has allocated it
          * already.  The size better be the same as the size we are trying to
          * initialize to, or there is a name conflict (or worse).
          */
         if (result->size != size)
         {
             LWLockRelease(ShmemIndexLock);
             ereport(ERROR,
                     (errmsg("ShmemIndex entry size is wrong for data structure"
                             " \"%s\": expected %zu, actual %zu",
                             name, size, result->size)));
         }
         structPtr = result->location;
     }
     else
     {
         Size    allocated_size;
 
         /* It isn't in the table yet. allocate and initialize it */
         structPtr = ShmemAllocRaw(size, &allocated_size);
         if (structPtr == NULL)
         {
             /* out of memory; remove the failed ShmemIndex entry */
             hash_search(ShmemIndex, name, HASH_REMOVE, NULL);
             LWLockRelease(ShmemIndexLock);
             ereport(ERROR,
                     (errcode(ERRCODE_OUT_OF_MEMORY),
                      errmsg("not enough shared memory for data structure"
                             " \"%s\" (%zu bytes requested)",
                             name, size)));
         }
         result->size = size;
         result->allocated_size = allocated_size;
         result->location = structPtr;
     }
 
     LWLockRelease(ShmemIndexLock);
 
     Assert(ShmemAddrIsValid(structPtr));
 
     Assert(structPtr == (void *) CACHELINEALIGN(structPtr));
 
     return structPtr;
 }

Variable Documentation

◆ ShmemBase

void* ShmemBase

static

Definition at line 84 of file shmem.c.

Referenced by InitShmemAccess(), ShmemAddrIsValid(), ShmemAllocRaw(), and ShmemAllocUnlocked().

◆ ShmemEnd

void* ShmemEnd

static

Definition at line 86 of file shmem.c.

Referenced by InitShmemAccess(), and ShmemAddrIsValid().

◆ ShmemIndex

HTAB* ShmemIndex = NULL

static

Definition at line 91 of file shmem.c.

◆ ShmemLock

slock_t* ShmemLock

Definition at line 88 of file shmem.c.

Referenced by InitShmemAllocation(), LWLockNewTrancheId(), PostmasterMarkPIDForWorkerNotify(), and ShmemAllocRaw().

◆ ShmemSegHdr

PGShmemHeader* ShmemSegHdr

static

Definition at line 82 of file shmem.c.

Referenced by InitShmemAllocation(), and ShmemInitStruct().

Macros

Functions

Variables

Macro Definition Documentation

◆ PG_GET_SHMEM_SIZES_COLS

Function Documentation

◆ add_size()

◆ InitShmemAccess()

◆ InitShmemAllocation()

◆ InitShmemIndex()

◆ mul_size()

◆ pg_get_shmem_allocations()

◆ ShmemAddrIsValid()

◆ ShmemAlloc()

◆ ShmemAllocNoError()

◆ ShmemAllocRaw()

◆ ShmemAllocUnlocked()

◆ ShmemInitHash()

◆ ShmemInitStruct()

Variable Documentation

◆ ShmemBase

◆ ShmemEnd

◆ ShmemIndex

◆ ShmemLock

◆ ShmemSegHdr