Header And Logo
|
#include "postgres.h"#include <limits.h>#include "access/xact.h"#include "storage/shmem.h"#include "storage/spin.h"#include "utils/dynahash.h"#include "utils/memutils.h"
Go to the source code of this file.
Data Structures | |
| struct | HASHHDR |
| struct | HTAB |
Defines | |
| #define | DEF_SEGSIZE 256 |
| #define | DEF_SEGSIZE_SHIFT 8 |
| #define | DEF_DIRSIZE 256 |
| #define | DEF_FFACTOR 1 |
| #define | IS_PARTITIONED(hctl) ((hctl)->num_partitions != 0) |
| #define | ELEMENTKEY(helem) (((char *)(helem)) + MAXALIGN(sizeof(HASHELEMENT))) |
| #define | ELEMENT_FROM_KEY(key) ((HASHELEMENT *) (((char *) (key)) - MAXALIGN(sizeof(HASHELEMENT)))) |
| #define | MOD(x, y) ((x) & ((y)-1)) |
| #define | MAX_SEQ_SCANS 100 |
Typedefs | |
| typedef HASHELEMENT * | HASHBUCKET |
| typedef HASHBUCKET * | HASHSEGMENT |
Functions | |
| static void * | DynaHashAlloc (Size size) |
| static HASHSEGMENT | seg_alloc (HTAB *hashp) |
| static bool | element_alloc (HTAB *hashp, int nelem) |
| static bool | dir_realloc (HTAB *hashp) |
| static bool | expand_table (HTAB *hashp) |
| static HASHBUCKET | get_hash_entry (HTAB *hashp) |
| static void | hdefault (HTAB *hashp) |
| static int | choose_nelem_alloc (Size entrysize) |
| static bool | init_htab (HTAB *hashp, long nelem) |
| static void | hash_corrupted (HTAB *hashp) |
| static long | next_pow2_long (long num) |
| static int | next_pow2_int (long num) |
| static void | register_seq_scan (HTAB *hashp) |
| static void | deregister_seq_scan (HTAB *hashp) |
| static bool | has_seq_scans (HTAB *hashp) |
| static int | string_compare (const char *key1, const char *key2, Size keysize) |
| HTAB * | hash_create (const char *tabname, long nelem, HASHCTL *info, int flags) |
| Size | hash_estimate_size (long num_entries, Size entrysize) |
| long | hash_select_dirsize (long num_entries) |
| Size | hash_get_shared_size (HASHCTL *info, int flags) |
| void | hash_destroy (HTAB *hashp) |
| void | hash_stats (const char *where, HTAB *hashp) |
| uint32 | get_hash_value (HTAB *hashp, const void *keyPtr) |
| static uint32 | calc_bucket (HASHHDR *hctl, uint32 hash_val) |
| void * | hash_search (HTAB *hashp, const void *keyPtr, HASHACTION action, bool *foundPtr) |
| void * | hash_search_with_hash_value (HTAB *hashp, const void *keyPtr, uint32 hashvalue, HASHACTION action, bool *foundPtr) |
| bool | hash_update_hash_key (HTAB *hashp, void *existingEntry, const void *newKeyPtr) |
| long | hash_get_num_entries (HTAB *hashp) |
| void | hash_seq_init (HASH_SEQ_STATUS *status, HTAB *hashp) |
| void * | hash_seq_search (HASH_SEQ_STATUS *status) |
| void | hash_seq_term (HASH_SEQ_STATUS *status) |
| void | hash_freeze (HTAB *hashp) |
| int | my_log2 (long num) |
| void | AtEOXact_HashTables (bool isCommit) |
| void | AtEOSubXact_HashTables (bool isCommit, int nestDepth) |
Variables | |
| static MemoryContext | CurrentDynaHashCxt = NULL |
| static HTAB * | seq_scan_tables [MAX_SEQ_SCANS] |
| static int | seq_scan_level [MAX_SEQ_SCANS] |
| static int | num_seq_scans = 0 |
| #define DEF_DIRSIZE 256 |
Definition at line 97 of file dynahash.c.
| #define DEF_FFACTOR 1 |
Definition at line 98 of file dynahash.c.
Referenced by hash_estimate_size(), and hash_select_dirsize().
| #define DEF_SEGSIZE 256 |
Definition at line 95 of file dynahash.c.
Referenced by hash_estimate_size(), and hash_select_dirsize().
| #define DEF_SEGSIZE_SHIFT 8 |
Definition at line 96 of file dynahash.c.
| #define ELEMENT_FROM_KEY | ( | key | ) | ((HASHELEMENT *) (((char *) (key)) - MAXALIGN(sizeof(HASHELEMENT)))) |
Definition at line 189 of file dynahash.c.
Referenced by hash_update_hash_key().
| #define ELEMENTKEY | ( | helem | ) | (((char *)(helem)) + MAXALIGN(sizeof(HASHELEMENT))) |
Definition at line 184 of file dynahash.c.
Referenced by hash_search_with_hash_value(), hash_seq_search(), and hash_update_hash_key().
| #define IS_PARTITIONED | ( | hctl | ) | ((hctl)->num_partitions != 0) |
Definition at line 153 of file dynahash.c.
Referenced by element_alloc(), expand_table(), get_hash_entry(), hash_search_with_hash_value(), and init_htab().
| #define MAX_SEQ_SCANS 100 |
Definition at line 1627 of file dynahash.c.
Referenced by register_seq_scan().
| #define MOD | ( | x, | ||
| y | ||||
| ) | ((x) & ((y)-1)) |
Definition at line 195 of file dynahash.c.
Referenced by expand_table(), hash_search_with_hash_value(), hash_seq_search(), and hash_update_hash_key().
| typedef HASHELEMENT* HASHBUCKET |
Definition at line 102 of file dynahash.c.
| typedef HASHBUCKET* HASHSEGMENT |
Definition at line 105 of file dynahash.c.
| void AtEOSubXact_HashTables | ( | bool | isCommit, | |
| int | nestDepth | |||
| ) |
Definition at line 1709 of file dynahash.c.
References elog, i, num_seq_scans, seq_scan_level, and WARNING.
Referenced by AbortSubTransaction(), and CommitSubTransaction().
{
int i;
/*
* Search backward to make cleanup easy. Note we must check all entries,
* not only those at the end of the array, because deletion technique
* doesn't keep them in order.
*/
for (i = num_seq_scans - 1; i >= 0; i--)
{
if (seq_scan_level[i] >= nestDepth)
{
if (isCommit)
elog(WARNING, "leaked hash_seq_search scan for hash table %p",
seq_scan_tables[i]);
seq_scan_tables[i] = seq_scan_tables[num_seq_scans - 1];
seq_scan_level[i] = seq_scan_level[num_seq_scans - 1];
num_seq_scans--;
}
}
}
| void AtEOXact_HashTables | ( | bool | isCommit | ) |
Definition at line 1683 of file dynahash.c.
References elog, i, num_seq_scans, and WARNING.
Referenced by AbortTransaction(), BackgroundWriterMain(), CheckpointerMain(), CommitTransaction(), PrepareTransaction(), and WalWriterMain().
{
/*
* During abort cleanup, open scans are expected; just silently clean 'em
* out. An open scan at commit means someone forgot a hash_seq_term()
* call, so complain.
*
* Note: it's tempting to try to print the tabname here, but refrain for
* fear of touching deallocated memory. This isn't a user-facing message
* anyway, so it needn't be pretty.
*/
if (isCommit)
{
int i;
for (i = 0; i < num_seq_scans; i++)
{
elog(WARNING, "leaked hash_seq_search scan for hash table %p",
seq_scan_tables[i]);
}
}
num_seq_scans = 0;
}
Definition at line 767 of file dynahash.c.
References HASHHDR::high_mask, HASHHDR::low_mask, and HASHHDR::max_bucket.
Referenced by expand_table(), hash_search_with_hash_value(), and hash_update_hash_key().
{
uint32 bucket;
bucket = hash_val & hctl->high_mask;
if (bucket > hctl->max_bucket)
bucket = bucket & hctl->low_mask;
return bucket;
}
| static int choose_nelem_alloc | ( | Size | entrysize | ) | [static] |
Definition at line 504 of file dynahash.c.
References MAXALIGN.
Referenced by hash_estimate_size(), and init_htab().
{
int nelem_alloc;
Size elementSize;
Size allocSize;
/* Each element has a HASHELEMENT header plus user data. */
/* NB: this had better match element_alloc() */
elementSize = MAXALIGN(sizeof(HASHELEMENT)) + MAXALIGN(entrysize);
/*
* The idea here is to choose nelem_alloc at least 32, but round up so
* that the allocation request will be a power of 2 or just less. This
* makes little difference for hash tables in shared memory, but for hash
* tables managed by palloc, the allocation request will be rounded up to
* a power of 2 anyway. If we fail to take this into account, we'll waste
* as much as half the allocated space.
*/
allocSize = 32 * 4; /* assume elementSize at least 8 */
do
{
allocSize <<= 1;
nelem_alloc = allocSize / elementSize;
} while (nelem_alloc < 32);
return nelem_alloc;
}
| static void deregister_seq_scan | ( | HTAB * | hashp | ) | [static] |
Definition at line 1648 of file dynahash.c.
References elog, ERROR, i, num_seq_scans, seq_scan_level, and HTAB::tabname.
Referenced by hash_seq_term().
{
int i;
/* Search backward since it's most likely at the stack top */
for (i = num_seq_scans - 1; i >= 0; i--)
{
if (seq_scan_tables[i] == hashp)
{
seq_scan_tables[i] = seq_scan_tables[num_seq_scans - 1];
seq_scan_level[i] = seq_scan_level[num_seq_scans - 1];
num_seq_scans--;
return;
}
}
elog(ERROR, "no hash_seq_search scan for hash table \"%s\"",
hashp->tabname);
}
Definition at line 1447 of file dynahash.c.
References HTAB::alloc, Assert, HTAB::dir, HASHHDR::dsize, DynaHashAlloc(), HTAB::hctl, HTAB::hcxt, HASHHDR::max_dsize, MemSet, NO_MAX_DSIZE, NULL, and pfree().
Referenced by expand_table().
{
HASHSEGMENT *p;
HASHSEGMENT *old_p;
long new_dsize;
long old_dirsize;
long new_dirsize;
if (hashp->hctl->max_dsize != NO_MAX_DSIZE)
return false;
/* Reallocate directory */
new_dsize = hashp->hctl->dsize << 1;
old_dirsize = hashp->hctl->dsize * sizeof(HASHSEGMENT);
new_dirsize = new_dsize * sizeof(HASHSEGMENT);
old_p = hashp->dir;
CurrentDynaHashCxt = hashp->hcxt;
p = (HASHSEGMENT *) hashp->alloc((Size) new_dirsize);
if (p != NULL)
{
memcpy(p, old_p, old_dirsize);
MemSet(((char *) p) + old_dirsize, 0, new_dirsize - old_dirsize);
hashp->dir = p;
hashp->hctl->dsize = new_dsize;
/* XXX assume the allocator is palloc, so we know how to free */
Assert(hashp->alloc == DynaHashAlloc);
pfree(old_p);
return true;
}
return false;
}
| static void * DynaHashAlloc | ( | Size | size | ) | [static] |
Definition at line 229 of file dynahash.c.
References Assert, MemoryContextAlloc(), and MemoryContextIsValid.
Referenced by dir_realloc(), hash_create(), hash_destroy(), and hash_search_with_hash_value().
{
Assert(MemoryContextIsValid(CurrentDynaHashCxt));
return MemoryContextAlloc(CurrentDynaHashCxt, size);
}
Definition at line 1505 of file dynahash.c.
References HTAB::alloc, HASHHDR::entrysize, HASHHDR::freeList, HTAB::hctl, HTAB::hcxt, i, IS_PARTITIONED, HTAB::isfixed, HASHELEMENT::link, MAXALIGN, HASHHDR::mutex, SpinLockAcquire, and SpinLockRelease.
Referenced by get_hash_entry(), and hash_create().
{
/* use volatile pointer to prevent code rearrangement */
volatile HASHHDR *hctlv = hashp->hctl;
Size elementSize;
HASHELEMENT *firstElement;
HASHELEMENT *tmpElement;
HASHELEMENT *prevElement;
int i;
if (hashp->isfixed)
return false;
/* Each element has a HASHELEMENT header plus user data. */
elementSize = MAXALIGN(sizeof(HASHELEMENT)) + MAXALIGN(hctlv->entrysize);
CurrentDynaHashCxt = hashp->hcxt;
firstElement = (HASHELEMENT *) hashp->alloc(nelem * elementSize);
if (!firstElement)
return false;
/* prepare to link all the new entries into the freelist */
prevElement = NULL;
tmpElement = firstElement;
for (i = 0; i < nelem; i++)
{
tmpElement->link = prevElement;
prevElement = tmpElement;
tmpElement = (HASHELEMENT *) (((char *) tmpElement) + elementSize);
}
/* if partitioned, must lock to touch freeList */
if (IS_PARTITIONED(hctlv))
SpinLockAcquire(&hctlv->mutex);
/* freelist could be nonempty if two backends did this concurrently */
firstElement->link = hctlv->freeList;
hctlv->freeList = prevElement;
if (IS_PARTITIONED(hctlv))
SpinLockRelease(&hctlv->mutex);
return true;
}
Definition at line 1350 of file dynahash.c.
References Assert, calc_bucket(), HTAB::dir, dir_realloc(), HASHHDR::dsize, HASHELEMENT::hashvalue, HTAB::hctl, HASHHDR::high_mask, IS_PARTITIONED, HASHELEMENT::link, HASHHDR::low_mask, HASHHDR::max_bucket, MOD, HASHHDR::nsegs, seg_alloc(), HTAB::sshift, and HTAB::ssize.
Referenced by hash_search_with_hash_value().
{
HASHHDR *hctl = hashp->hctl;
HASHSEGMENT old_seg,
new_seg;
long old_bucket,
new_bucket;
long new_segnum,
new_segndx;
long old_segnum,
old_segndx;
HASHBUCKET *oldlink,
*newlink;
HASHBUCKET currElement,
nextElement;
Assert(!IS_PARTITIONED(hctl));
#ifdef HASH_STATISTICS
hash_expansions++;
#endif
new_bucket = hctl->max_bucket + 1;
new_segnum = new_bucket >> hashp->sshift;
new_segndx = MOD(new_bucket, hashp->ssize);
if (new_segnum >= hctl->nsegs)
{
/* Allocate new segment if necessary -- could fail if dir full */
if (new_segnum >= hctl->dsize)
if (!dir_realloc(hashp))
return false;
if (!(hashp->dir[new_segnum] = seg_alloc(hashp)))
return false;
hctl->nsegs++;
}
/* OK, we created a new bucket */
hctl->max_bucket++;
/*
* *Before* changing masks, find old bucket corresponding to same hash
* values; values in that bucket may need to be relocated to new bucket.
* Note that new_bucket is certainly larger than low_mask at this point,
* so we can skip the first step of the regular hash mask calc.
*/
old_bucket = (new_bucket & hctl->low_mask);
/*
* If we crossed a power of 2, readjust masks.
*/
if ((uint32) new_bucket > hctl->high_mask)
{
hctl->low_mask = hctl->high_mask;
hctl->high_mask = (uint32) new_bucket | hctl->low_mask;
}
/*
* Relocate records to the new bucket. NOTE: because of the way the hash
* masking is done in calc_bucket, only one old bucket can need to be
* split at this point. With a different way of reducing the hash value,
* that might not be true!
*/
old_segnum = old_bucket >> hashp->sshift;
old_segndx = MOD(old_bucket, hashp->ssize);
old_seg = hashp->dir[old_segnum];
new_seg = hashp->dir[new_segnum];
oldlink = &old_seg[old_segndx];
newlink = &new_seg[new_segndx];
for (currElement = *oldlink;
currElement != NULL;
currElement = nextElement)
{
nextElement = currElement->link;
if ((long) calc_bucket(hctl, currElement->hashvalue) == old_bucket)
{
*oldlink = currElement;
oldlink = &currElement->link;
}
else
{
*newlink = currElement;
newlink = &currElement->link;
}
}
/* don't forget to terminate the rebuilt hash chains... */
*oldlink = NULL;
*newlink = NULL;
return true;
}
| static HASHBUCKET get_hash_entry | ( | HTAB * | hashp | ) | [static] |
Definition at line 1149 of file dynahash.c.
References element_alloc(), HASHHDR::freeList, HTAB::hctl, IS_PARTITIONED, HASHELEMENT::link, HASHHDR::mutex, HASHHDR::nelem_alloc, HASHHDR::nentries, NULL, SpinLockAcquire, and SpinLockRelease.
Referenced by hash_search_with_hash_value().
{
/* use volatile pointer to prevent code rearrangement */
volatile HASHHDR *hctlv = hashp->hctl;
HASHBUCKET newElement;
for (;;)
{
/* if partitioned, must lock to touch nentries and freeList */
if (IS_PARTITIONED(hctlv))
SpinLockAcquire(&hctlv->mutex);
/* try to get an entry from the freelist */
newElement = hctlv->freeList;
if (newElement != NULL)
break;
/* no free elements. allocate another chunk of buckets */
if (IS_PARTITIONED(hctlv))
SpinLockRelease(&hctlv->mutex);
if (!element_alloc(hashp, hctlv->nelem_alloc))
{
/* out of memory */
return NULL;
}
}
/* remove entry from freelist, bump nentries */
hctlv->freeList = newElement->link;
hctlv->nentries++;
if (IS_PARTITIONED(hctlv))
SpinLockRelease(&hctlv->mutex);
return newElement;
}
Definition at line 760 of file dynahash.c.
References HTAB::hash, and HTAB::keysize.
Referenced by BufTableHashCode(), and LockTagHashCode().
Definition at line 1669 of file dynahash.c.
References i, and num_seq_scans.
Referenced by hash_freeze(), and hash_search_with_hash_value().
{
int i;
for (i = 0; i < num_seq_scans; i++)
{
if (seq_scan_tables[i] == hashp)
return true;
}
return false;
}
| static void hash_corrupted | ( | HTAB * | hashp | ) | [static] |
Definition at line 1553 of file dynahash.c.
References elog, FATAL, HTAB::isshared, PANIC, and HTAB::tabname.
Referenced by hash_search_with_hash_value(), and hash_update_hash_key().
Definition at line 267 of file dynahash.c.
References HASHCTL::alloc, HTAB::alloc, ALLOCSET_DEFAULT_INITSIZE, ALLOCSET_DEFAULT_MAXSIZE, ALLOCSET_DEFAULT_MINSIZE, AllocSetContextCreate(), Assert, HTAB::dir, HASHCTL::dsize, HASHHDR::dsize, DynaHashAlloc(), element_alloc(), elog, HASHHDR::entrysize, HASHCTL::entrysize, ereport, errcode(), errmsg(), ERROR, HASHCTL::ffactor, HASHHDR::ffactor, HTAB::frozen, HASHCTL::hash, HTAB::hash, HASH_ALLOC, HASH_ATTACH, HASH_COMPARE, HASH_CONTEXT, HASH_DIRSIZE, HASH_ELEM, HASH_FFACTOR, HASH_FIXED_SIZE, HASH_FUNCTION, HASH_KEYCOPY, HASH_PARTITION, HASH_SEGMENT, HASH_SHARED_MEM, HASHCTL::hctl, HTAB::hctl, HTAB::hcxt, HASHCTL::hcxt, hdefault(), init_htab(), HTAB::isfixed, HTAB::isshared, HASHCTL::keycopy, HTAB::keycopy, HASHCTL::keysize, HASHHDR::keysize, HTAB::keysize, HASHCTL::match, HTAB::match, HASHCTL::max_dsize, HASHHDR::max_dsize, MemSet, my_log2(), next_pow2_int(), HASHHDR::num_partitions, HASHCTL::num_partitions, HASHHDR::sshift, HTAB::sshift, HASHCTL::ssize, HASHHDR::ssize, HTAB::ssize, string_compare(), string_hash(), strlcpy(), HTAB::tabname, and TopMemoryContext.
Referenced by _PG_init(), assign_record_type_typmod(), begin_heap_rewrite(), build_join_rel_hash(), BuildEventTriggerCache(), BuildTupleHashTable(), CompactCheckpointerRequestQueue(), compute_array_stats(), compute_tsvector_stats(), createConnHash(), do_autovacuum(), EnablePortalManager(), find_oper_cache_entry(), find_rendezvous_variable(), get_btree_test_op(), get_json_object_as_hash(), GetComboCommandId(), GetConnection(), GetSerializableTransactionSnapshotInt(), gistInitBuildBuffers(), gistInitParentMap(), init_procedure_caches(), init_timezone_hashtable(), init_ts_config_cache(), InitializeAttoptCache(), InitializeTableSpaceCache(), InitLocalBuffers(), InitLocks(), InitQueryHashTable(), load_categories_hash(), log_invalid_page(), lookup_collation_cache(), lookup_ts_dictionary_cache(), lookup_ts_parser_cache(), lookup_type_cache(), LookupOpclassInfo(), mdinit(), pgstat_collect_oids(), pgstat_init_function_usage(), pgstat_read_statsfiles(), plpgsql_HashTableInit(), PLy_add_exceptions(), populate_recordset_object_start(), rebuild_database_list(), record_C_func(), RelationCacheInitialize(), reset_dbentry_counters(), ResetUnloggedRelationsInDbspaceDir(), ri_InitHashTables(), select_perl_context(), ShmemInitHash(), smgropen(), tbm_create_pagetable(), and transformGraph().
{
HTAB *hashp;
HASHHDR *hctl;
/*
* For shared hash tables, we have a local hash header (HTAB struct) that
* we allocate in TopMemoryContext; all else is in shared memory.
*
* For non-shared hash tables, everything including the hash header is in
* a memory context created specially for the hash table --- this makes
* hash_destroy very simple. The memory context is made a child of either
* a context specified by the caller, or TopMemoryContext if nothing is
* specified.
*/
if (flags & HASH_SHARED_MEM)
{
/* Set up to allocate the hash header */
CurrentDynaHashCxt = TopMemoryContext;
}
else
{
/* Create the hash table's private memory context */
if (flags & HASH_CONTEXT)
CurrentDynaHashCxt = info->hcxt;
else
CurrentDynaHashCxt = TopMemoryContext;
CurrentDynaHashCxt = AllocSetContextCreate(CurrentDynaHashCxt,
tabname,
ALLOCSET_DEFAULT_MINSIZE,
ALLOCSET_DEFAULT_INITSIZE,
ALLOCSET_DEFAULT_MAXSIZE);
}
/* Initialize the hash header, plus a copy of the table name */
hashp = (HTAB *) DynaHashAlloc(sizeof(HTAB) + strlen(tabname) +1);
MemSet(hashp, 0, sizeof(HTAB));
hashp->tabname = (char *) (hashp + 1);
strcpy(hashp->tabname, tabname);
if (flags & HASH_FUNCTION)
hashp->hash = info->hash;
else
hashp->hash = string_hash; /* default hash function */
/*
* If you don't specify a match function, it defaults to string_compare if
* you used string_hash (either explicitly or by default) and to memcmp
* otherwise. (Prior to PostgreSQL 7.4, memcmp was always used.)
*/
if (flags & HASH_COMPARE)
hashp->match = info->match;
else if (hashp->hash == string_hash)
hashp->match = (HashCompareFunc) string_compare;
else
hashp->match = memcmp;
/*
* Similarly, the key-copying function defaults to strlcpy or memcpy.
*/
if (flags & HASH_KEYCOPY)
hashp->keycopy = info->keycopy;
else if (hashp->hash == string_hash)
hashp->keycopy = (HashCopyFunc) strlcpy;
else
hashp->keycopy = memcpy;
if (flags & HASH_ALLOC)
hashp->alloc = info->alloc;
else
hashp->alloc = DynaHashAlloc;
if (flags & HASH_SHARED_MEM)
{
/*
* ctl structure and directory are preallocated for shared memory
* tables. Note that HASH_DIRSIZE and HASH_ALLOC had better be set as
* well.
*/
hashp->hctl = info->hctl;
hashp->dir = (HASHSEGMENT *) (((char *) info->hctl) + sizeof(HASHHDR));
hashp->hcxt = NULL;
hashp->isshared = true;
/* hash table already exists, we're just attaching to it */
if (flags & HASH_ATTACH)
{
/* make local copies of some heavily-used values */
hctl = hashp->hctl;
hashp->keysize = hctl->keysize;
hashp->ssize = hctl->ssize;
hashp->sshift = hctl->sshift;
return hashp;
}
}
else
{
/* setup hash table defaults */
hashp->hctl = NULL;
hashp->dir = NULL;
hashp->hcxt = CurrentDynaHashCxt;
hashp->isshared = false;
}
if (!hashp->hctl)
{
hashp->hctl = (HASHHDR *) hashp->alloc(sizeof(HASHHDR));
if (!hashp->hctl)
ereport(ERROR,
(errcode(ERRCODE_OUT_OF_MEMORY),
errmsg("out of memory")));
}
hashp->frozen = false;
hdefault(hashp);
hctl = hashp->hctl;
if (flags & HASH_PARTITION)
{
/* Doesn't make sense to partition a local hash table */
Assert(flags & HASH_SHARED_MEM);
/*
* The number of partitions had better be a power of 2. Also, it must
* be less than INT_MAX (see init_htab()), so call the int version of
* next_pow2.
*/
Assert(info->num_partitions == next_pow2_int(info->num_partitions));
hctl->num_partitions = info->num_partitions;
}
if (flags & HASH_SEGMENT)
{
hctl->ssize = info->ssize;
hctl->sshift = my_log2(info->ssize);
/* ssize had better be a power of 2 */
Assert(hctl->ssize == (1L << hctl->sshift));
}
if (flags & HASH_FFACTOR)
hctl->ffactor = info->ffactor;
/*
* SHM hash tables have fixed directory size passed by the caller.
*/
if (flags & HASH_DIRSIZE)
{
hctl->max_dsize = info->max_dsize;
hctl->dsize = info->dsize;
}
/*
* hash table now allocates space for key and data but you have to say how
* much space to allocate
*/
if (flags & HASH_ELEM)
{
Assert(info->entrysize >= info->keysize);
hctl->keysize = info->keysize;
hctl->entrysize = info->entrysize;
}
/* make local copies of heavily-used constant fields */
hashp->keysize = hctl->keysize;
hashp->ssize = hctl->ssize;
hashp->sshift = hctl->sshift;
/* Build the hash directory structure */
if (!init_htab(hashp, nelem))
elog(ERROR, "failed to initialize hash table \"%s\"", hashp->tabname);
/*
* For a shared hash table, preallocate the requested number of elements.
* This reduces problems with run-time out-of-shared-memory conditions.
*
* For a non-shared hash table, preallocate the requested number of
* elements if it's less than our chosen nelem_alloc. This avoids wasting
* space if the caller correctly estimates a small table size.
*/
if ((flags & HASH_SHARED_MEM) ||
nelem < hctl->nelem_alloc)
{
if (!element_alloc(hashp, (int) nelem))
ereport(ERROR,
(errcode(ERRCODE_OUT_OF_MEMORY),
errmsg("out of memory")));
}
if (flags & HASH_FIXED_SIZE)
hashp->isfixed = true;
return hashp;
}
| void hash_destroy | ( | HTAB * | hashp | ) |
Definition at line 714 of file dynahash.c.
References HTAB::alloc, Assert, DynaHashAlloc(), hash_stats(), HTAB::hcxt, MemoryContextDelete(), and NULL.
Referenced by clear_external_function_hash(), CompactCheckpointerRequestQueue(), InitLocks(), pgstat_recv_dropdb(), pgstat_recv_resetcounter(), pgstat_vacuum_stat(), populate_recordset_object_end(), PostPrepare_PredicateLocks(), ReleasePredicateLocks(), ResetUnloggedRelationsInDbspaceDir(), SetForwardFsyncRequests(), tbm_free(), and XLogCheckInvalidPages().
{
if (hashp != NULL)
{
/* allocation method must be one we know how to free, too */
Assert(hashp->alloc == DynaHashAlloc);
/* so this hashtable must have it's own context */
Assert(hashp->hcxt != NULL);
hash_stats("destroy", hashp);
/*
* Free everything by destroying the hash table's memory context.
*/
MemoryContextDelete(hashp->hcxt);
}
}
Definition at line 632 of file dynahash.c.
References add_size(), choose_nelem_alloc(), DEF_FFACTOR, DEF_SEGSIZE, MAXALIGN, mul_size(), and next_pow2_long().
Referenced by BufTableShmemSize(), CreateSharedMemoryAndSemaphores(), LockShmemSize(), pgss_memsize(), and PredicateLockShmemSize().
{
Size size;
long nBuckets,
nSegments,
nDirEntries,
nElementAllocs,
elementSize,
elementAllocCnt;
/* estimate number of buckets wanted */
nBuckets = next_pow2_long((num_entries - 1) / DEF_FFACTOR + 1);
/* # of segments needed for nBuckets */
nSegments = next_pow2_long((nBuckets - 1) / DEF_SEGSIZE + 1);
/* directory entries */
nDirEntries = DEF_DIRSIZE;
while (nDirEntries < nSegments)
nDirEntries <<= 1; /* dir_alloc doubles dsize at each call */
/* fixed control info */
size = MAXALIGN(sizeof(HASHHDR)); /* but not HTAB, per above */
/* directory */
size = add_size(size, mul_size(nDirEntries, sizeof(HASHSEGMENT)));
/* segments */
size = add_size(size, mul_size(nSegments,
MAXALIGN(DEF_SEGSIZE * sizeof(HASHBUCKET))));
/* elements --- allocated in groups of choose_nelem_alloc() entries */
elementAllocCnt = choose_nelem_alloc(entrysize);
nElementAllocs = (num_entries - 1) / elementAllocCnt + 1;
elementSize = MAXALIGN(sizeof(HASHELEMENT)) + MAXALIGN(entrysize);
size = add_size(size,
mul_size(nElementAllocs,
mul_size(elementAllocCnt, elementSize)));
return size;
}
| void hash_freeze | ( | HTAB * | hashp | ) |
Definition at line 1333 of file dynahash.c.
References elog, ERROR, HTAB::frozen, has_seq_scans(), HTAB::isshared, and HTAB::tabname.
| long hash_get_num_entries | ( | HTAB * | hashp | ) |
Definition at line 1191 of file dynahash.c.
References HTAB::hctl, and HASHHDR::nentries.
Referenced by compute_array_stats(), compute_tsvector_stats(), entry_alloc(), entry_dealloc(), get_crosstab_tuplestore(), GetLockStatusData(), GetPredicateLockStatusData(), GetRunningTransactionLocks(), json_populate_record(), pgss_shmem_shutdown(), pgstat_vacuum_stat(), ResetUnloggedRelationsInDbspaceDir(), transformGraph(), and XLogHaveInvalidPages().
Definition at line 703 of file dynahash.c.
References Assert, HASHCTL::dsize, HASH_DIRSIZE, and HASHCTL::max_dsize.
Referenced by ShmemInitHash().
{
Assert(flags & HASH_DIRSIZE);
Assert(info->dsize == info->max_dsize);
return sizeof(HASHHDR) + info->dsize * sizeof(HASHSEGMENT);
}
| void* hash_search | ( | HTAB * | hashp, | |
| const void * | keyPtr, | |||
| HASHACTION | action, | |||
| bool * | foundPtr | |||
| ) |
Definition at line 806 of file dynahash.c.
References HTAB::hash, hash_search_with_hash_value(), and HTAB::keysize.
Referenced by assign_record_type_typmod(), AtEOSubXact_RelationCache(), AtEOXact_RelationCache(), build_join_rel(), build_join_rel_hash(), BuildEventTriggerCache(), CheckAndPromotePredicateLockRequest(), CheckForSerializableConflictOut(), CompactCheckpointerRequestQueue(), compile_plperl_function(), compile_pltcl_function(), compute_array_stats(), compute_tsvector_stats(), createNewConnection(), deleteConnection(), do_autovacuum(), DropAllPredicateLocksFromTable(), DropAllPreparedStatements(), DropPreparedStatement(), DropRelFileNodeAllLocalBuffers(), DropRelFileNodeLocalBuffers(), entry_alloc(), entry_dealloc(), entry_reset(), EventCacheLookup(), FetchPreparedStatement(), find_funcstat_entry(), find_join_rel(), find_oper_cache_entry(), find_rendezvous_variable(), FindTupleHashEntry(), forget_invalid_pages(), forget_invalid_pages_db(), get_attribute_options(), get_btree_test_op(), get_pgstat_tabentry_relid(), get_tablespace(), GetComboCommandId(), GetConnection(), getConnectionByName(), getState(), gistGetNodeBuffer(), gistGetParent(), gistMemorizeParent(), gistRelocateBuildBuffersOnSplit(), hash_object_field_end(), InitPredicateLocks(), InvalidateAttoptCacheCallback(), InvalidateOprCacheCallBack(), InvalidateTableSpaceCacheCallback(), json_populate_record(), LocalBufferAlloc(), LocalPrefetchBuffer(), LockAcquireExtended(), LockHasWaiters(), LockRelease(), log_invalid_page(), lookup_C_func(), lookup_collation_cache(), lookup_ts_config_cache(), lookup_ts_dictionary_cache(), lookup_ts_parser_cache(), lookup_type_cache(), LookupOpclassInfo(), LookupTupleHashEntry(), make_oper_cache_entry(), mdsync(), pg_tzset(), pgss_store(), pgstat_collect_oids(), pgstat_fetch_stat_dbentry(), pgstat_fetch_stat_funcentry(), pgstat_fetch_stat_tabentry(), pgstat_get_db_entry(), pgstat_get_tab_entry(), pgstat_init_function_usage(), pgstat_read_db_statsfile(), pgstat_read_statsfiles(), pgstat_recv_dropdb(), pgstat_recv_funcpurge(), pgstat_recv_funcstat(), pgstat_recv_resetsinglecounter(), pgstat_recv_tabpurge(), pgstat_recv_tabstat(), pgstat_vacuum_stat(), plperl_spi_exec_prepared(), plperl_spi_freeplan(), plperl_spi_prepare(), plperl_spi_query_prepared(), plpgsql_HashTableDelete(), plpgsql_HashTableInsert(), plpgsql_HashTableLookup(), pltcl_fetch_interp(), PLy_generate_spi_exceptions(), PLy_procedure_get(), PLy_spi_subtransaction_abort(), populate_recordset_object_end(), populate_recordset_object_field_end(), predicatelock_twophase_recover(), PredicateLockExists(), PredicateLockTwoPhaseFinish(), prune_element_hashtable(), prune_lexemes_hashtable(), rebuild_database_list(), record_C_func(), RegisterPredicateLockingXid(), ReleaseOneSerializableXact(), RememberFsyncRequest(), RemoveLocalLock(), ResetUnloggedRelationsInDbspaceDir(), rewrite_heap_dead_tuple(), rewrite_heap_tuple(), ri_FetchPreparedPlan(), ri_HashCompareOp(), ri_HashPreparedPlan(), ri_LoadConstraintInfo(), select_perl_context(), ShmemInitStruct(), smgrclose(), smgrclosenode(), smgropen(), StorePreparedStatement(), table_recheck_autovac(), tbm_create_pagetable(), tbm_find_pageentry(), tbm_get_pageentry(), tbm_intersect(), tbm_mark_page_lossy(), and tbm_page_is_lossy().
{
return hash_search_with_hash_value(hashp,
keyPtr,
hashp->hash(keyPtr, hashp->keysize),
action,
foundPtr);
}
| void* hash_search_with_hash_value | ( | HTAB * | hashp, | |
| const void * | keyPtr, | |||
| uint32 | hashvalue, | |||
| HASHACTION | action, | |||
| bool * | foundPtr | |||
| ) |
Definition at line 819 of file dynahash.c.
References HTAB::alloc, Assert, calc_bucket(), HTAB::dir, DynaHashAlloc(), ELEMENTKEY, elog, ereport, errcode(), errmsg(), ERROR, expand_table(), HASHHDR::ffactor, HASHHDR::freeList, HTAB::frozen, get_hash_entry(), has_seq_scans(), hash_corrupted(), HASH_ENTER, HASH_ENTER_NULL, HASH_FIND, HASH_REMOVE, HASHELEMENT::hashvalue, HTAB::hctl, IS_PARTITIONED, HTAB::isshared, HTAB::keycopy, HTAB::keysize, HASHELEMENT::link, HTAB::match, HASHHDR::max_bucket, MOD, HASHHDR::mutex, HASHHDR::nentries, NULL, SpinLockAcquire, SpinLockRelease, HTAB::sshift, HTAB::ssize, and HTAB::tabname.
Referenced by BufTableDelete(), BufTableInsert(), BufTableLookup(), CheckTargetForConflictsIn(), CleanUpLock(), ClearOldPredicateLocks(), CreatePredicateLock(), DecrementParentLocks(), DeleteChildTargetLocks(), DeleteLockTarget(), DropAllPredicateLocksFromTable(), FastPathGetRelationLockEntry(), GetLockConflicts(), hash_search(), lock_twophase_recover(), LockAcquireExtended(), LockRefindAndRelease(), LockRelease(), PageIsPredicateLocked(), PredicateLockAcquire(), ReleaseOneSerializableXact(), RemoveScratchTarget(), RemoveTargetIfNoLongerUsed(), RestoreScratchTarget(), SetupLockInTable(), and TransferPredicateLocksToNewTarget().
{
HASHHDR *hctl = hashp->hctl;
Size keysize;
uint32 bucket;
long segment_num;
long segment_ndx;
HASHSEGMENT segp;
HASHBUCKET currBucket;
HASHBUCKET *prevBucketPtr;
HashCompareFunc match;
#if HASH_STATISTICS
hash_accesses++;
hctl->accesses++;
#endif
/*
* If inserting, check if it is time to split a bucket.
*
* NOTE: failure to expand table is not a fatal error, it just means we
* have to run at higher fill factor than we wanted. However, if we're
* using the palloc allocator then it will throw error anyway on
* out-of-memory, so we must do this before modifying the table.
*/
if (action == HASH_ENTER || action == HASH_ENTER_NULL)
{
/*
* Can't split if running in partitioned mode, nor if frozen, nor if
* table is the subject of any active hash_seq_search scans. Strange
* order of these tests is to try to check cheaper conditions first.
*/
if (!IS_PARTITIONED(hctl) && !hashp->frozen &&
hctl->nentries / (long) (hctl->max_bucket + 1) >= hctl->ffactor &&
!has_seq_scans(hashp))
(void) expand_table(hashp);
}
/*
* Do the initial lookup
*/
bucket = calc_bucket(hctl, hashvalue);
segment_num = bucket >> hashp->sshift;
segment_ndx = MOD(bucket, hashp->ssize);
segp = hashp->dir[segment_num];
if (segp == NULL)
hash_corrupted(hashp);
prevBucketPtr = &segp[segment_ndx];
currBucket = *prevBucketPtr;
/*
* Follow collision chain looking for matching key
*/
match = hashp->match; /* save one fetch in inner loop */
keysize = hashp->keysize; /* ditto */
while (currBucket != NULL)
{
if (currBucket->hashvalue == hashvalue &&
match(ELEMENTKEY(currBucket), keyPtr, keysize) == 0)
break;
prevBucketPtr = &(currBucket->link);
currBucket = *prevBucketPtr;
#if HASH_STATISTICS
hash_collisions++;
hctl->collisions++;
#endif
}
if (foundPtr)
*foundPtr = (bool) (currBucket != NULL);
/*
* OK, now what?
*/
switch (action)
{
case HASH_FIND:
if (currBucket != NULL)
return (void *) ELEMENTKEY(currBucket);
return NULL;
case HASH_REMOVE:
if (currBucket != NULL)
{
/* use volatile pointer to prevent code rearrangement */
volatile HASHHDR *hctlv = hctl;
/* if partitioned, must lock to touch nentries and freeList */
if (IS_PARTITIONED(hctlv))
SpinLockAcquire(&hctlv->mutex);
Assert(hctlv->nentries > 0);
hctlv->nentries--;
/* remove record from hash bucket's chain. */
*prevBucketPtr = currBucket->link;
/* add the record to the freelist for this table. */
currBucket->link = hctlv->freeList;
hctlv->freeList = currBucket;
if (IS_PARTITIONED(hctlv))
SpinLockRelease(&hctlv->mutex);
/*
* better hope the caller is synchronizing access to this
* element, because someone else is going to reuse it the next
* time something is added to the table
*/
return (void *) ELEMENTKEY(currBucket);
}
return NULL;
case HASH_ENTER_NULL:
/* ENTER_NULL does not work with palloc-based allocator */
Assert(hashp->alloc != DynaHashAlloc);
/* FALL THRU */
case HASH_ENTER:
/* Return existing element if found, else create one */
if (currBucket != NULL)
return (void *) ELEMENTKEY(currBucket);
/* disallow inserts if frozen */
if (hashp->frozen)
elog(ERROR, "cannot insert into frozen hashtable \"%s\"",
hashp->tabname);
currBucket = get_hash_entry(hashp);
if (currBucket == NULL)
{
/* out of memory */
if (action == HASH_ENTER_NULL)
return NULL;
/* report a generic message */
if (hashp->isshared)
ereport(ERROR,
(errcode(ERRCODE_OUT_OF_MEMORY),
errmsg("out of shared memory")));
else
ereport(ERROR,
(errcode(ERRCODE_OUT_OF_MEMORY),
errmsg("out of memory")));
}
/* link into hashbucket chain */
*prevBucketPtr = currBucket;
currBucket->link = NULL;
/* copy key into record */
currBucket->hashvalue = hashvalue;
hashp->keycopy(ELEMENTKEY(currBucket), keyPtr, keysize);
/*
* Caller is expected to fill the data field on return. DO NOT
* insert any code that could possibly throw error here, as doing
* so would leave the table entry incomplete and hence corrupt the
* caller's data structure.
*/
return (void *) ELEMENTKEY(currBucket);
}
elog(ERROR, "unrecognized hash action code: %d", (int) action);
return NULL; /* keep compiler quiet */
}
| long hash_select_dirsize | ( | long | num_entries | ) |
Definition at line 679 of file dynahash.c.
References DEF_FFACTOR, DEF_SEGSIZE, and next_pow2_long().
Referenced by ShmemInitHash().
{
long nBuckets,
nSegments,
nDirEntries;
/* estimate number of buckets wanted */
nBuckets = next_pow2_long((num_entries - 1) / DEF_FFACTOR + 1);
/* # of segments needed for nBuckets */
nSegments = next_pow2_long((nBuckets - 1) / DEF_SEGSIZE + 1);
/* directory entries */
nDirEntries = DEF_DIRSIZE;
while (nDirEntries < nSegments)
nDirEntries <<= 1; /* dir_alloc doubles dsize at each call */
return nDirEntries;
}
| void hash_seq_init | ( | HASH_SEQ_STATUS * | status, | |
| HTAB * | hashp | |||
| ) |
Definition at line 1227 of file dynahash.c.
References HASH_SEQ_STATUS::curBucket, HASH_SEQ_STATUS::curEntry, HTAB::frozen, HASH_SEQ_STATUS::hashp, and register_seq_scan().
Referenced by AtAbort_Portals(), AtCleanup_Portals(), AtEOSubXact_RelationCache(), AtEOXact_RelationCache(), AtPrepare_Locks(), AtSubAbort_Portals(), AtSubCleanup_Portals(), AtSubCommit_Portals(), CheckTableForSerializableConflictIn(), compute_array_stats(), compute_tsvector_stats(), dblink_get_connections(), DropAllPredicateLocksFromTable(), DropAllPreparedStatements(), end_heap_rewrite(), entry_dealloc(), entry_reset(), forget_invalid_pages(), forget_invalid_pages_db(), GetLockStatusData(), GetPredicateLockStatusData(), GetRunningTransactionLocks(), InvalidateAttoptCacheCallback(), InvalidateConstraintCacheCallBack(), InvalidateOprCacheCallBack(), InvalidateOprProofCacheCallBack(), InvalidateTableSpaceCacheCallback(), InvalidateTSCacheCallBack(), LockReassignCurrentOwner(), LockReleaseAll(), LockReleaseCurrentOwner(), LockReleaseSession(), mdsync(), packGraph(), pg_cursor(), pg_prepared_statement(), pg_stat_statements(), pgfdw_subxact_callback(), pgfdw_xact_callback(), pgss_shmem_shutdown(), pgstat_send_funcstats(), pgstat_vacuum_stat(), pgstat_write_db_statsfile(), pgstat_write_statsfiles(), plperl_fini(), PortalHashTableDeleteAll(), PostPrepare_Locks(), PreCommit_Portals(), prune_element_hashtable(), prune_lexemes_hashtable(), rebuild_database_list(), RelationCacheInitializePhase3(), RelationCacheInvalidate(), RememberFsyncRequest(), selectColorTrigrams(), smgrcloseall(), tbm_begin_iterate(), tbm_intersect(), tbm_lossify(), tbm_union(), ThereAreNoReadyPortals(), TypeCacheRelCallback(), write_relcache_init_file(), and XLogCheckInvalidPages().
{
status->hashp = hashp;
status->curBucket = 0;
status->curEntry = NULL;
if (!hashp->frozen)
register_seq_scan(hashp);
}
| void* hash_seq_search | ( | HASH_SEQ_STATUS * | status | ) |
Definition at line 1237 of file dynahash.c.
References HASH_SEQ_STATUS::curBucket, HASH_SEQ_STATUS::curEntry, HTAB::dir, ELEMENTKEY, hash_seq_term(), HASH_SEQ_STATUS::hashp, HTAB::hctl, HASHELEMENT::link, HASHHDR::max_bucket, MOD, NULL, HTAB::sshift, and HTAB::ssize.
Referenced by AtAbort_Portals(), AtCleanup_Portals(), AtEOSubXact_RelationCache(), AtEOXact_RelationCache(), AtPrepare_Locks(), AtSubAbort_Portals(), AtSubCleanup_Portals(), AtSubCommit_Portals(), CheckTableForSerializableConflictIn(), compute_array_stats(), compute_tsvector_stats(), dblink_get_connections(), DropAllPredicateLocksFromTable(), DropAllPreparedStatements(), end_heap_rewrite(), entry_dealloc(), entry_reset(), forget_invalid_pages(), forget_invalid_pages_db(), GetLockStatusData(), GetPredicateLockStatusData(), GetRunningTransactionLocks(), InvalidateAttoptCacheCallback(), InvalidateConstraintCacheCallBack(), InvalidateOprCacheCallBack(), InvalidateOprProofCacheCallBack(), InvalidateTableSpaceCacheCallback(), InvalidateTSCacheCallBack(), LockReassignCurrentOwner(), LockReleaseAll(), LockReleaseCurrentOwner(), LockReleaseSession(), mdsync(), packGraph(), pg_cursor(), pg_prepared_statement(), pg_stat_statements(), pgfdw_subxact_callback(), pgfdw_xact_callback(), pgss_shmem_shutdown(), pgstat_send_funcstats(), pgstat_vacuum_stat(), pgstat_write_db_statsfile(), pgstat_write_statsfiles(), plperl_fini(), PortalHashTableDeleteAll(), PostPrepare_Locks(), PreCommit_Portals(), prune_element_hashtable(), prune_lexemes_hashtable(), rebuild_database_list(), RelationCacheInitializePhase3(), RelationCacheInvalidate(), RememberFsyncRequest(), selectColorTrigrams(), smgrcloseall(), tbm_begin_iterate(), tbm_intersect(), tbm_lossify(), tbm_union(), ThereAreNoReadyPortals(), TypeCacheRelCallback(), write_relcache_init_file(), and XLogCheckInvalidPages().
{
HTAB *hashp;
HASHHDR *hctl;
uint32 max_bucket;
long ssize;
long segment_num;
long segment_ndx;
HASHSEGMENT segp;
uint32 curBucket;
HASHELEMENT *curElem;
if ((curElem = status->curEntry) != NULL)
{
/* Continuing scan of curBucket... */
status->curEntry = curElem->link;
if (status->curEntry == NULL) /* end of this bucket */
++status->curBucket;
return (void *) ELEMENTKEY(curElem);
}
/*
* Search for next nonempty bucket starting at curBucket.
*/
curBucket = status->curBucket;
hashp = status->hashp;
hctl = hashp->hctl;
ssize = hashp->ssize;
max_bucket = hctl->max_bucket;
if (curBucket > max_bucket)
{
hash_seq_term(status);
return NULL; /* search is done */
}
/*
* first find the right segment in the table directory.
*/
segment_num = curBucket >> hashp->sshift;
segment_ndx = MOD(curBucket, ssize);
segp = hashp->dir[segment_num];
/*
* Pick up the first item in this bucket's chain. If chain is not empty
* we can begin searching it. Otherwise we have to advance to find the
* next nonempty bucket. We try to optimize that case since searching a
* near-empty hashtable has to iterate this loop a lot.
*/
while ((curElem = segp[segment_ndx]) == NULL)
{
/* empty bucket, advance to next */
if (++curBucket > max_bucket)
{
status->curBucket = curBucket;
hash_seq_term(status);
return NULL; /* search is done */
}
if (++segment_ndx >= ssize)
{
segment_num++;
segment_ndx = 0;
segp = hashp->dir[segment_num];
}
}
/* Begin scan of curBucket... */
status->curEntry = curElem->link;
if (status->curEntry == NULL) /* end of this bucket */
++curBucket;
status->curBucket = curBucket;
return (void *) ELEMENTKEY(curElem);
}
| void hash_seq_term | ( | HASH_SEQ_STATUS * | status | ) |
Definition at line 1313 of file dynahash.c.
References deregister_seq_scan(), HTAB::frozen, and HASH_SEQ_STATUS::hashp.
Referenced by hash_seq_search(), PortalHashTableDeleteAll(), PreCommit_Portals(), RelationCacheInitializePhase3(), and tbm_lossify().
{
if (!status->hashp->frozen)
deregister_seq_scan(status->hashp);
}
| void hash_stats | ( | const char * | where, | |
| HTAB * | hashp | |||
| ) |
Definition at line 733 of file dynahash.c.
References HTAB::hctl, HASHHDR::keysize, HASHHDR::max_bucket, HASHHDR::nentries, and HASHHDR::nsegs.
Referenced by hash_destroy().
{
#if HASH_STATISTICS
fprintf(stderr, "%s: this HTAB -- accesses %ld collisions %ld\n",
where, hashp->hctl->accesses, hashp->hctl->collisions);
fprintf(stderr, "hash_stats: entries %ld keysize %ld maxp %u segmentcount %ld\n",
hashp->hctl->nentries, (long) hashp->hctl->keysize,
hashp->hctl->max_bucket, hashp->hctl->nsegs);
fprintf(stderr, "%s: total accesses %ld total collisions %ld\n",
where, hash_accesses, hash_collisions);
fprintf(stderr, "hash_stats: total expansions %ld\n",
hash_expansions);
#endif
}
Definition at line 1016 of file dynahash.c.
References calc_bucket(), HTAB::dir, ELEMENT_FROM_KEY, ELEMENTKEY, elog, ERROR, HTAB::frozen, HTAB::hash, hash_corrupted(), HASHELEMENT::hashvalue, HTAB::hctl, HTAB::keycopy, HTAB::keysize, HASHELEMENT::link, HTAB::match, MOD, NULL, HTAB::sshift, HTAB::ssize, and HTAB::tabname.
Referenced by PostPrepare_Locks().
{
HASHELEMENT *existingElement = ELEMENT_FROM_KEY(existingEntry);
HASHHDR *hctl = hashp->hctl;
uint32 newhashvalue;
Size keysize;
uint32 bucket;
uint32 newbucket;
long segment_num;
long segment_ndx;
HASHSEGMENT segp;
HASHBUCKET currBucket;
HASHBUCKET *prevBucketPtr;
HASHBUCKET *oldPrevPtr;
HashCompareFunc match;
#if HASH_STATISTICS
hash_accesses++;
hctl->accesses++;
#endif
/* disallow updates if frozen */
if (hashp->frozen)
elog(ERROR, "cannot update in frozen hashtable \"%s\"",
hashp->tabname);
/*
* Lookup the existing element using its saved hash value. We need to
* do this to be able to unlink it from its hash chain, but as a side
* benefit we can verify the validity of the passed existingEntry pointer.
*/
bucket = calc_bucket(hctl, existingElement->hashvalue);
segment_num = bucket >> hashp->sshift;
segment_ndx = MOD(bucket, hashp->ssize);
segp = hashp->dir[segment_num];
if (segp == NULL)
hash_corrupted(hashp);
prevBucketPtr = &segp[segment_ndx];
currBucket = *prevBucketPtr;
while (currBucket != NULL)
{
if (currBucket == existingElement)
break;
prevBucketPtr = &(currBucket->link);
currBucket = *prevBucketPtr;
}
if (currBucket == NULL)
elog(ERROR, "hash_update_hash_key argument is not in hashtable \"%s\"",
hashp->tabname);
oldPrevPtr = prevBucketPtr;
/*
* Now perform the equivalent of a HASH_ENTER operation to locate the
* hash chain we want to put the entry into.
*/
newhashvalue = hashp->hash(newKeyPtr, hashp->keysize);
newbucket = calc_bucket(hctl, newhashvalue);
segment_num = newbucket >> hashp->sshift;
segment_ndx = MOD(newbucket, hashp->ssize);
segp = hashp->dir[segment_num];
if (segp == NULL)
hash_corrupted(hashp);
prevBucketPtr = &segp[segment_ndx];
currBucket = *prevBucketPtr;
/*
* Follow collision chain looking for matching key
*/
match = hashp->match; /* save one fetch in inner loop */
keysize = hashp->keysize; /* ditto */
while (currBucket != NULL)
{
if (currBucket->hashvalue == newhashvalue &&
match(ELEMENTKEY(currBucket), newKeyPtr, keysize) == 0)
break;
prevBucketPtr = &(currBucket->link);
currBucket = *prevBucketPtr;
#if HASH_STATISTICS
hash_collisions++;
hctl->collisions++;
#endif
}
if (currBucket != NULL)
return false; /* collision with an existing entry */
currBucket = existingElement;
/*
* If old and new hash values belong to the same bucket, we need not
* change any chain links, and indeed should not since this simplistic
* update will corrupt the list if currBucket is the last element. (We
* cannot fall out earlier, however, since we need to scan the bucket to
* check for duplicate keys.)
*/
if (bucket != newbucket)
{
/* OK to remove record from old hash bucket's chain. */
*oldPrevPtr = currBucket->link;
/* link into new hashbucket chain */
*prevBucketPtr = currBucket;
currBucket->link = NULL;
}
/* copy new key into record */
currBucket->hashvalue = newhashvalue;
hashp->keycopy(ELEMENTKEY(currBucket), newKeyPtr, keysize);
/* rest of record is untouched */
return true;
}
| static void hdefault | ( | HTAB * | hashp | ) | [static] |
Definition at line 468 of file dynahash.c.
References HASHHDR::dsize, HASHHDR::entrysize, HASHHDR::ffactor, HASHHDR::freeList, HTAB::hctl, HASHHDR::keysize, HASHHDR::max_dsize, MemSet, HASHHDR::nentries, HASHHDR::nsegs, HASHHDR::num_partitions, HASHHDR::sshift, and HASHHDR::ssize.
Referenced by hash_create().
{
HASHHDR *hctl = hashp->hctl;
MemSet(hctl, 0, sizeof(HASHHDR));
hctl->nentries = 0;
hctl->freeList = NULL;
hctl->dsize = DEF_DIRSIZE;
hctl->nsegs = 0;
/* rather pointless defaults for key & entry size */
hctl->keysize = sizeof(char *);
hctl->entrysize = 2 * sizeof(char *);
hctl->num_partitions = 0; /* not partitioned */
hctl->ffactor = DEF_FFACTOR;
/* table has no fixed maximum size */
hctl->max_dsize = NO_MAX_DSIZE;
hctl->ssize = DEF_SEGSIZE;
hctl->sshift = DEF_SEGSIZE_SHIFT;
#ifdef HASH_STATISTICS
hctl->accesses = hctl->collisions = 0;
#endif
}
Definition at line 537 of file dynahash.c.
References HTAB::alloc, choose_nelem_alloc(), HTAB::dir, HASHHDR::dsize, HASHHDR::entrysize, HASHHDR::ffactor, HTAB::hctl, HTAB::hcxt, HASHHDR::high_mask, IS_PARTITIONED, HASHHDR::low_mask, HASHHDR::max_bucket, HASHHDR::mutex, HASHHDR::nelem_alloc, HASHHDR::nentries, next_pow2_int(), HASHHDR::nsegs, NULL, seg_alloc(), SpinLockInit, HASHHDR::sshift, and HASHHDR::ssize.
Referenced by hash_create().
{
HASHHDR *hctl = hashp->hctl;
HASHSEGMENT *segp;
int nbuckets;
int nsegs;
/*
* initialize mutex if it's a partitioned table
*/
if (IS_PARTITIONED(hctl))
SpinLockInit(&hctl->mutex);
/*
* Divide number of elements by the fill factor to determine a desired
* number of buckets. Allocate space for the next greater power of two
* number of buckets
*/
nbuckets = next_pow2_int((nelem - 1) / hctl->ffactor + 1);
/*
* In a partitioned table, nbuckets must be at least equal to
* num_partitions; were it less, keys with apparently different partition
* numbers would map to the same bucket, breaking partition independence.
* (Normally nbuckets will be much bigger; this is just a safety check.)
*/
while (nbuckets < hctl->num_partitions)
nbuckets <<= 1;
hctl->max_bucket = hctl->low_mask = nbuckets - 1;
hctl->high_mask = (nbuckets << 1) - 1;
/*
* Figure number of directory segments needed, round up to a power of 2
*/
nsegs = (nbuckets - 1) / hctl->ssize + 1;
nsegs = next_pow2_int(nsegs);
/*
* Make sure directory is big enough. If pre-allocated directory is too
* small, choke (caller screwed up).
*/
if (nsegs > hctl->dsize)
{
if (!(hashp->dir))
hctl->dsize = nsegs;
else
return false;
}
/* Allocate a directory */
if (!(hashp->dir))
{
CurrentDynaHashCxt = hashp->hcxt;
hashp->dir = (HASHSEGMENT *)
hashp->alloc(hctl->dsize * sizeof(HASHSEGMENT));
if (!hashp->dir)
return false;
}
/* Allocate initial segments */
for (segp = hashp->dir; hctl->nsegs < nsegs; hctl->nsegs++, segp++)
{
*segp = seg_alloc(hashp);
if (*segp == NULL)
return false;
}
/* Choose number of entries to allocate at a time */
hctl->nelem_alloc = choose_nelem_alloc(hctl->entrysize);
#if HASH_DEBUG
fprintf(stderr, "init_htab:\n%s%p\n%s%ld\n%s%ld\n%s%d\n%s%ld\n%s%u\n%s%x\n%s%x\n%s%ld\n%s%ld\n",
"TABLE POINTER ", hashp,
"DIRECTORY SIZE ", hctl->dsize,
"SEGMENT SIZE ", hctl->ssize,
"SEGMENT SHIFT ", hctl->sshift,
"FILL FACTOR ", hctl->ffactor,
"MAX BUCKET ", hctl->max_bucket,
"HIGH MASK ", hctl->high_mask,
"LOW MASK ", hctl->low_mask,
"NSEGS ", hctl->nsegs,
"NENTRIES ", hctl->nentries);
#endif
return true;
}
| int my_log2 | ( | long | num | ) |
Definition at line 1567 of file dynahash.c.
References i.
Referenced by ExecHashTableCreate(), hash_create(), next_pow2_int(), and next_pow2_long().
{
int i;
long limit;
/* guard against too-large input, which would put us into infinite loop */
if (num > LONG_MAX / 2)
num = LONG_MAX / 2;
for (i = 0, limit = 1; limit < num; i++, limit <<= 1)
;
return i;
}
| static int next_pow2_int | ( | long | num | ) | [static] |
Definition at line 1591 of file dynahash.c.
References my_log2().
Referenced by hash_create(), and init_htab().
{
if (num > INT_MAX / 2)
num = INT_MAX / 2;
return 1 << my_log2(num);
}
| static long next_pow2_long | ( | long | num | ) | [static] |
Definition at line 1583 of file dynahash.c.
References my_log2().
Referenced by hash_estimate_size(), and hash_select_dirsize().
{
/* my_log2's internal range check is sufficient */
return 1L << my_log2(num);
}
| static void register_seq_scan | ( | HTAB * | hashp | ) | [static] |
Definition at line 1636 of file dynahash.c.
References elog, ERROR, GetCurrentTransactionNestLevel(), MAX_SEQ_SCANS, num_seq_scans, seq_scan_level, and HTAB::tabname.
Referenced by hash_seq_init().
{
if (num_seq_scans >= MAX_SEQ_SCANS)
elog(ERROR, "too many active hash_seq_search scans, cannot start one on \"%s\"",
hashp->tabname);
seq_scan_tables[num_seq_scans] = hashp;
seq_scan_level[num_seq_scans] = GetCurrentTransactionNestLevel();
num_seq_scans++;
}
| static HASHSEGMENT seg_alloc | ( | HTAB * | hashp | ) | [static] |
Definition at line 1486 of file dynahash.c.
References HTAB::alloc, HTAB::hcxt, MemSet, and HTAB::ssize.
Referenced by expand_table(), and init_htab().
{
HASHSEGMENT segp;
CurrentDynaHashCxt = hashp->hcxt;
segp = (HASHSEGMENT) hashp->alloc(sizeof(HASHBUCKET) * hashp->ssize);
if (!segp)
return NULL;
MemSet(segp, 0, sizeof(HASHBUCKET) * hashp->ssize);
return segp;
}
| static int string_compare | ( | const char * | key1, | |
| const char * | key2, | |||
| Size | keysize | |||
| ) | [static] |
Definition at line 244 of file dynahash.c.
Referenced by hash_create().
{
return strncmp(key1, key2, keysize - 1);
}
MemoryContext CurrentDynaHashCxt = NULL [static] |
Definition at line 226 of file dynahash.c.
int num_seq_scans = 0 [static] |
Definition at line 1631 of file dynahash.c.
Referenced by AtEOSubXact_HashTables(), AtEOXact_HashTables(), deregister_seq_scan(), has_seq_scans(), and register_seq_scan().
int seq_scan_level[MAX_SEQ_SCANS] [static] |
Definition at line 1630 of file dynahash.c.
Referenced by AtEOSubXact_HashTables(), deregister_seq_scan(), and register_seq_scan().
HTAB* seq_scan_tables[MAX_SEQ_SCANS] [static] |
Definition at line 1629 of file dynahash.c.
1.7.1