PostgreSQL Source Code  git master
dsa.h File Reference
#include "port/atomics.h"
#include "storage/dsm.h"
Include dependency graph for dsa.h:
This graph shows which files directly or indirectly include this file:

Go to the source code of this file.

Macros

#define SIZEOF_DSA_POINTER   8
 
#define dsa_pointer_atomic_init   pg_atomic_init_u64
 
#define dsa_pointer_atomic_read   pg_atomic_read_u64
 
#define dsa_pointer_atomic_write   pg_atomic_write_u64
 
#define dsa_pointer_atomic_fetch_add   pg_atomic_fetch_add_u64
 
#define dsa_pointer_atomic_compare_exchange   pg_atomic_compare_exchange_u64
 
#define DSA_POINTER_FORMAT   "%016" INT64_MODIFIER "x"
 
#define DSA_ALLOC_HUGE   0x01 /* allow huge allocation (> 1 GB) */
 
#define DSA_ALLOC_NO_OOM   0x02 /* no failure if out-of-memory */
 
#define DSA_ALLOC_ZERO   0x04 /* zero allocated memory */
 
#define InvalidDsaPointer   ((dsa_pointer) 0)
 
#define DsaPointerIsValid(x)   ((x) != InvalidDsaPointer)
 
#define dsa_allocate(area, size)    dsa_allocate_extended(area, size, 0)
 
#define dsa_allocate0(area, size)    dsa_allocate_extended(area, size, DSA_ALLOC_ZERO)
 
#define DSA_HANDLE_INVALID   ((dsa_handle) DSM_HANDLE_INVALID)
 

Typedefs

typedef struct dsa_area dsa_area
 
typedef uint64 dsa_pointer
 
typedef pg_atomic_uint64 dsa_pointer_atomic
 
typedef dsm_handle dsa_handle
 

Functions

dsa_areadsa_create (int tranche_id)
 
dsa_areadsa_create_in_place (void *place, size_t size, int tranche_id, dsm_segment *segment)
 
dsa_areadsa_attach (dsa_handle handle)
 
dsa_areadsa_attach_in_place (void *place, dsm_segment *segment)
 
void dsa_release_in_place (void *place)
 
void dsa_on_dsm_detach_release_in_place (dsm_segment *, Datum)
 
void dsa_on_shmem_exit_release_in_place (int, Datum)
 
void dsa_pin_mapping (dsa_area *area)
 
void dsa_detach (dsa_area *area)
 
void dsa_pin (dsa_area *area)
 
void dsa_unpin (dsa_area *area)
 
void dsa_set_size_limit (dsa_area *area, size_t limit)
 
size_t dsa_minimum_size (void)
 
dsa_handle dsa_get_handle (dsa_area *area)
 
dsa_pointer dsa_allocate_extended (dsa_area *area, size_t size, int flags)
 
void dsa_free (dsa_area *area, dsa_pointer dp)
 
void * dsa_get_address (dsa_area *area, dsa_pointer dp)
 
void dsa_trim (dsa_area *area)
 
void dsa_dump (dsa_area *area)
 

Macro Definition Documentation

◆ DSA_ALLOC_HUGE

#define DSA_ALLOC_HUGE   0x01 /* allow huge allocation (> 1 GB) */

Definition at line 73 of file dsa.h.

◆ DSA_ALLOC_NO_OOM

#define DSA_ALLOC_NO_OOM   0x02 /* no failure if out-of-memory */

Definition at line 74 of file dsa.h.

◆ DSA_ALLOC_ZERO

#define DSA_ALLOC_ZERO   0x04 /* zero allocated memory */

Definition at line 75 of file dsa.h.

◆ dsa_allocate

#define dsa_allocate (   area,
  size 
)     dsa_allocate_extended(area, size, 0)

Definition at line 84 of file dsa.h.

◆ dsa_allocate0

#define dsa_allocate0 (   area,
  size 
)     dsa_allocate_extended(area, size, DSA_ALLOC_ZERO)

Definition at line 88 of file dsa.h.

◆ DSA_HANDLE_INVALID

#define DSA_HANDLE_INVALID   ((dsa_handle) DSM_HANDLE_INVALID)

Definition at line 103 of file dsa.h.

◆ dsa_pointer_atomic_compare_exchange

#define dsa_pointer_atomic_compare_exchange   pg_atomic_compare_exchange_u64

Definition at line 68 of file dsa.h.

◆ dsa_pointer_atomic_fetch_add

#define dsa_pointer_atomic_fetch_add   pg_atomic_fetch_add_u64

Definition at line 67 of file dsa.h.

◆ dsa_pointer_atomic_init

#define dsa_pointer_atomic_init   pg_atomic_init_u64

Definition at line 64 of file dsa.h.

◆ dsa_pointer_atomic_read

#define dsa_pointer_atomic_read   pg_atomic_read_u64

Definition at line 65 of file dsa.h.

◆ dsa_pointer_atomic_write

#define dsa_pointer_atomic_write   pg_atomic_write_u64

Definition at line 66 of file dsa.h.

◆ DSA_POINTER_FORMAT

#define DSA_POINTER_FORMAT   "%016" INT64_MODIFIER "x"

Definition at line 69 of file dsa.h.

◆ DsaPointerIsValid

#define DsaPointerIsValid (   x)    ((x) != InvalidDsaPointer)

Definition at line 81 of file dsa.h.

◆ InvalidDsaPointer

#define InvalidDsaPointer   ((dsa_pointer) 0)

Definition at line 78 of file dsa.h.

◆ SIZEOF_DSA_POINTER

#define SIZEOF_DSA_POINTER   8

Definition at line 42 of file dsa.h.

Typedef Documentation

◆ dsa_area

typedef struct dsa_area dsa_area

Definition at line 1 of file dsa.h.

◆ dsa_handle

Definition at line 100 of file dsa.h.

◆ dsa_pointer

typedef uint64 dsa_pointer

Definition at line 62 of file dsa.h.

◆ dsa_pointer_atomic

Definition at line 63 of file dsa.h.

Function Documentation

◆ dsa_allocate_extended()

dsa_pointer dsa_allocate_extended ( dsa_area area,
size_t  size,
int  flags 
)

Definition at line 678 of file dsa.c.

679 {
680  uint16 size_class;
681  dsa_pointer start_pointer;
682  dsa_segment_map *segment_map;
683  dsa_pointer result;
684 
685  Assert(size > 0);
686 
687  /* Sanity check on huge individual allocation size. */
688  if (((flags & DSA_ALLOC_HUGE) != 0 && !AllocHugeSizeIsValid(size)) ||
689  ((flags & DSA_ALLOC_HUGE) == 0 && !AllocSizeIsValid(size)))
690  elog(ERROR, "invalid DSA memory alloc request size %zu", size);
691 
692  /*
693  * If bigger than the largest size class, just grab a run of pages from
694  * the free page manager, instead of allocating an object from a pool.
695  * There will still be a span, but it's a special class of span that
696  * manages this whole allocation and simply gives all pages back to the
697  * free page manager when dsa_free is called.
698  */
699  if (size > dsa_size_classes[lengthof(dsa_size_classes) - 1])
700  {
701  size_t npages = fpm_size_to_pages(size);
702  size_t first_page;
703  dsa_pointer span_pointer;
705 
706  /* Obtain a span object. */
707  span_pointer = alloc_object(area, DSA_SCLASS_BLOCK_OF_SPANS);
708  if (!DsaPointerIsValid(span_pointer))
709  {
710  /* Raise error unless asked not to. */
711  if ((flags & DSA_ALLOC_NO_OOM) == 0)
712  ereport(ERROR,
713  (errcode(ERRCODE_OUT_OF_MEMORY),
714  errmsg("out of memory"),
715  errdetail("Failed on DSA request of size %zu.",
716  size)));
717  return InvalidDsaPointer;
718  }
719 
721 
722  /* Find a segment from which to allocate. */
723  segment_map = get_best_segment(area, npages);
724  if (segment_map == NULL)
725  segment_map = make_new_segment(area, npages);
726  if (segment_map == NULL)
727  {
728  /* Can't make any more segments: game over. */
730  dsa_free(area, span_pointer);
731 
732  /* Raise error unless asked not to. */
733  if ((flags & DSA_ALLOC_NO_OOM) == 0)
734  ereport(ERROR,
735  (errcode(ERRCODE_OUT_OF_MEMORY),
736  errmsg("out of memory"),
737  errdetail("Failed on DSA request of size %zu.",
738  size)));
739  return InvalidDsaPointer;
740  }
741 
742  /*
743  * Ask the free page manager for a run of pages. This should always
744  * succeed, since both get_best_segment and make_new_segment should
745  * only return a non-NULL pointer if it actually contains enough
746  * contiguous freespace. If it does fail, something in our backend
747  * private state is out of whack, so use FATAL to kill the process.
748  */
749  if (!FreePageManagerGet(segment_map->fpm, npages, &first_page))
750  elog(FATAL,
751  "dsa_allocate could not find %zu free pages", npages);
753 
754  start_pointer = DSA_MAKE_POINTER(get_segment_index(area, segment_map),
755  first_page * FPM_PAGE_SIZE);
756 
757  /* Initialize span and pagemap. */
759  LW_EXCLUSIVE);
760  init_span(area, span_pointer, pool, start_pointer, npages,
762  segment_map->pagemap[first_page] = span_pointer;
764 
765  /* Zero-initialize the memory if requested. */
766  if ((flags & DSA_ALLOC_ZERO) != 0)
767  memset(dsa_get_address(area, start_pointer), 0, size);
768 
769  return start_pointer;
770  }
771 
772  /* Map allocation to a size class. */
774  {
775  int mapidx;
776 
777  /* For smaller sizes we have a lookup table... */
778  mapidx = ((size + DSA_SIZE_CLASS_MAP_QUANTUM - 1) /
780  size_class = dsa_size_class_map[mapidx];
781  }
782  else
783  {
784  uint16 min;
785  uint16 max;
786 
787  /* ... and for the rest we search by binary chop. */
789  max = lengthof(dsa_size_classes) - 1;
790 
791  while (min < max)
792  {
793  uint16 mid = (min + max) / 2;
794  uint16 class_size = dsa_size_classes[mid];
795 
796  if (class_size < size)
797  min = mid + 1;
798  else
799  max = mid;
800  }
801 
802  size_class = min;
803  }
804  Assert(size <= dsa_size_classes[size_class]);
805  Assert(size_class == 0 || size > dsa_size_classes[size_class - 1]);
806 
807  /* Attempt to allocate an object from the appropriate pool. */
808  result = alloc_object(area, size_class);
809 
810  /* Check for failure to allocate. */
811  if (!DsaPointerIsValid(result))
812  {
813  /* Raise error unless asked not to. */
814  if ((flags & DSA_ALLOC_NO_OOM) == 0)
815  ereport(ERROR,
816  (errcode(ERRCODE_OUT_OF_MEMORY),
817  errmsg("out of memory"),
818  errdetail("Failed on DSA request of size %zu.", size)));
819  return InvalidDsaPointer;
820  }
821 
822  /* Zero-initialize the memory if requested. */
823  if ((flags & DSA_ALLOC_ZERO) != 0)
824  memset(dsa_get_address(area, result), 0, size);
825 
826  return result;
827 }
unsigned short uint16
Definition: c.h:494
#define lengthof(array)
Definition: c.h:777
static const uint16 dsa_size_classes[]
Definition: dsa.c:248
#define DSA_AREA_LOCK(area)
Definition: dsa.c:155
#define DSA_MAKE_POINTER(segment_number, offset)
Definition: dsa.c:115
#define get_segment_index(area, segment_map_ptr)
Definition: dsa.c:393
static dsa_pointer alloc_object(dsa_area *area, int size_class)
Definition: dsa.c:1454
#define DSA_SIZE_CLASS_MAP_QUANTUM
Definition: dsa.c:281
static const uint8 dsa_size_class_map[]
Definition: dsa.c:271
static dsa_segment_map * make_new_segment(dsa_area *area, size_t requested_pages)
Definition: dsa.c:2061
void * dsa_get_address(dsa_area *area, dsa_pointer dp)
Definition: dsa.c:949
#define DSA_SCLASS_LOCK(area, sclass)
Definition: dsa.c:156
#define DSA_SCLASS_BLOCK_OF_SPANS
Definition: dsa.c:262
#define DSA_SCLASS_SPAN_LARGE
Definition: dsa.c:263
static void init_span(dsa_area *area, dsa_pointer span_pointer, dsa_area_pool *pool, dsa_pointer start, size_t npages, uint16 size_class)
Definition: dsa.c:1359
static dsa_segment_map * get_best_segment(dsa_area *area, size_t npages)
Definition: dsa.c:1990
void dsa_free(dsa_area *area, dsa_pointer dp)
Definition: dsa.c:833
uint64 dsa_pointer
Definition: dsa.h:62
#define InvalidDsaPointer
Definition: dsa.h:78
#define DSA_ALLOC_NO_OOM
Definition: dsa.h:74
#define DsaPointerIsValid(x)
Definition: dsa.h:81
#define DSA_ALLOC_HUGE
Definition: dsa.h:73
#define DSA_ALLOC_ZERO
Definition: dsa.h:75
int errdetail(const char *fmt,...)
Definition: elog.c:1202
int errcode(int sqlerrcode)
Definition: elog.c:858
int errmsg(const char *fmt,...)
Definition: elog.c:1069
#define FATAL
Definition: elog.h:41
#define ERROR
Definition: elog.h:39
#define ereport(elevel,...)
Definition: elog.h:149
bool FreePageManagerGet(FreePageManager *fpm, Size npages, Size *first_page)
Definition: freepage.c:210
#define fpm_size_to_pages(sz)
Definition: freepage.h:74
#define FPM_PAGE_SIZE
Definition: freepage.h:30
Assert(fmt[strlen(fmt) - 1] !='\n')
bool LWLockAcquire(LWLock *lock, LWLockMode mode)
Definition: lwlock.c:1195
void LWLockRelease(LWLock *lock)
Definition: lwlock.c:1808
@ LW_EXCLUSIVE
Definition: lwlock.h:116
#define AllocHugeSizeIsValid(size)
Definition: memutils.h:49
#define AllocSizeIsValid(size)
Definition: memutils.h:42
dsa_area_pool pools[DSA_NUM_SIZE_CLASSES]
Definition: dsa.c:321
dsa_area_control * control
Definition: dsa.c:369
FreePageManager * fpm
Definition: dsa.c:356
dsa_pointer * pagemap
Definition: dsa.c:357

References alloc_object(), AllocHugeSizeIsValid, AllocSizeIsValid, Assert(), dsa_area::control, DSA_ALLOC_HUGE, DSA_ALLOC_NO_OOM, DSA_ALLOC_ZERO, DSA_AREA_LOCK, dsa_free(), dsa_get_address(), DSA_MAKE_POINTER, DSA_SCLASS_BLOCK_OF_SPANS, DSA_SCLASS_LOCK, DSA_SCLASS_SPAN_LARGE, dsa_size_class_map, DSA_SIZE_CLASS_MAP_QUANTUM, dsa_size_classes, DsaPointerIsValid, elog(), ereport, errcode(), errdetail(), errmsg(), ERROR, FATAL, dsa_segment_map::fpm, FPM_PAGE_SIZE, fpm_size_to_pages, FreePageManagerGet(), get_best_segment(), get_segment_index, init_span(), InvalidDsaPointer, lengthof, LW_EXCLUSIVE, LWLockAcquire(), LWLockRelease(), make_new_segment(), dsa_segment_map::pagemap, and dsa_area_control::pools.

Referenced by dshash_create(), and pagetable_allocate().

◆ dsa_attach()

dsa_area* dsa_attach ( dsa_handle  handle)

Definition at line 519 of file dsa.c.

520 {
521  dsm_segment *segment;
522  dsa_area *area;
523 
524  /*
525  * An area handle is really a DSM segment handle for the first segment, so
526  * we go ahead and attach to that.
527  */
528  segment = dsm_attach(handle);
529  if (segment == NULL)
530  ereport(ERROR,
531  (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
532  errmsg("could not attach to dynamic shared area")));
533 
534  area = attach_internal(dsm_segment_address(segment), segment, handle);
535 
536  /* Clean up when the control segment detaches. */
539 
540  return area;
541 }
void dsa_on_dsm_detach_release_in_place(dsm_segment *segment, Datum place)
Definition: dsa.c:585
static dsa_area * attach_internal(void *place, dsm_segment *segment, dsa_handle handle)
Definition: dsa.c:1308
void * dsm_segment_address(dsm_segment *seg)
Definition: dsm.c:1066
void on_dsm_detach(dsm_segment *seg, on_dsm_detach_callback function, Datum arg)
Definition: dsm.c:1103
dsm_segment * dsm_attach(dsm_handle h)
Definition: dsm.c:638
static Datum PointerGetDatum(const void *X)
Definition: postgres.h:322
Definition: dsa.c:367

References attach_internal(), dsa_on_dsm_detach_release_in_place(), dsm_attach(), dsm_segment_address(), ereport, errcode(), errmsg(), ERROR, on_dsm_detach(), and PointerGetDatum().

Referenced by logicalrep_launcher_attach_dshmem().

◆ dsa_attach_in_place()

dsa_area* dsa_attach_in_place ( void *  place,
dsm_segment segment 
)

Definition at line 554 of file dsa.c.

555 {
556  dsa_area *area;
557 
558  area = attach_internal(place, NULL, DSA_HANDLE_INVALID);
559 
560  /*
561  * Clean up when the control segment detaches, if a containing DSM segment
562  * was provided.
563  */
564  if (segment != NULL)
566  PointerGetDatum(place));
567 
568  return area;
569 }
#define DSA_HANDLE_INVALID
Definition: dsa.h:103

References attach_internal(), DSA_HANDLE_INVALID, dsa_on_dsm_detach_release_in_place(), on_dsm_detach(), and PointerGetDatum().

Referenced by AttachSession(), ParallelQueryMain(), and pgstat_attach_shmem().

◆ dsa_create()

dsa_area* dsa_create ( int  tranche_id)

Definition at line 433 of file dsa.c.

434 {
435  dsm_segment *segment;
436  dsa_area *area;
437 
438  /*
439  * Create the DSM segment that will hold the shared control object and the
440  * first segment of usable space.
441  */
442  segment = dsm_create(DSA_INITIAL_SEGMENT_SIZE, 0);
443 
444  /*
445  * All segments backing this area are pinned, so that DSA can explicitly
446  * control their lifetime (otherwise a newly created segment belonging to
447  * this area might be freed when the only backend that happens to have it
448  * mapped in ends, corrupting the area).
449  */
450  dsm_pin_segment(segment);
451 
452  /* Create a new DSA area with the control object in this segment. */
453  area = create_internal(dsm_segment_address(segment),
455  tranche_id,
456  dsm_segment_handle(segment), segment);
457 
458  /* Clean up when the control segment detaches. */
461 
462  return area;
463 }
#define DSA_INITIAL_SEGMENT_SIZE
Definition: dsa.c:69
static dsa_area * create_internal(void *place, size_t size, int tranche_id, dsm_handle control_handle, dsm_segment *control_segment)
Definition: dsa.c:1208
dsm_handle dsm_segment_handle(dsm_segment *seg)
Definition: dsm.c:1094
dsm_segment * dsm_create(Size size, int flags)
Definition: dsm.c:489
void dsm_pin_segment(dsm_segment *seg)
Definition: dsm.c:928

References create_internal(), DSA_INITIAL_SEGMENT_SIZE, dsa_on_dsm_detach_release_in_place(), dsm_create(), dsm_pin_segment(), dsm_segment_address(), dsm_segment_handle(), on_dsm_detach(), and PointerGetDatum().

Referenced by logicalrep_launcher_attach_dshmem().

◆ dsa_create_in_place()

dsa_area* dsa_create_in_place ( void *  place,
size_t  size,
int  tranche_id,
dsm_segment segment 
)

Definition at line 482 of file dsa.c.

484 {
485  dsa_area *area;
486 
487  area = create_internal(place, size, tranche_id,
488  DSM_HANDLE_INVALID, NULL);
489 
490  /*
491  * Clean up when the control segment detaches, if a containing DSM segment
492  * was provided.
493  */
494  if (segment != NULL)
496  PointerGetDatum(place));
497 
498  return area;
499 }
#define DSM_HANDLE_INVALID
Definition: dsm_impl.h:58

References create_internal(), dsa_on_dsm_detach_release_in_place(), DSM_HANDLE_INVALID, on_dsm_detach(), and PointerGetDatum().

Referenced by ExecInitParallelPlan(), GetSessionDsmHandle(), and StatsShmemInit().

◆ dsa_detach()

void dsa_detach ( dsa_area area)

Definition at line 1932 of file dsa.c.

1933 {
1934  int i;
1935 
1936  /* Detach from all segments. */
1937  for (i = 0; i <= area->high_segment_index; ++i)
1938  if (area->segment_maps[i].segment != NULL)
1939  dsm_detach(area->segment_maps[i].segment);
1940 
1941  /*
1942  * Note that 'detaching' (= detaching from DSM segments) doesn't include
1943  * 'releasing' (= adjusting the reference count). It would be nice to
1944  * combine these operations, but client code might never get around to
1945  * calling dsa_detach because of an error path, and a detach hook on any
1946  * particular segment is too late to detach other segments in the area
1947  * without risking a 'leak' warning in the non-error path.
1948  */
1949 
1950  /* Free the backend-local area object. */
1951  pfree(area);
1952 }
void dsm_detach(dsm_segment *seg)
Definition: dsm.c:776
int i
Definition: isn.c:73
void pfree(void *pointer)
Definition: mcxt.c:1456
dsa_segment_map segment_maps[DSA_MAX_SEGMENTS]
Definition: dsa.c:380
dsa_segment_index high_segment_index
Definition: dsa.c:383
dsm_segment * segment
Definition: dsa.c:353

References dsm_detach(), dsa_area::high_segment_index, i, pfree(), dsa_segment_map::segment, and dsa_area::segment_maps.

Referenced by DetachSession(), ExecParallelCleanup(), ParallelQueryMain(), pgstat_detach_shmem(), and StatsShmemInit().

◆ dsa_dump()

void dsa_dump ( dsa_area area)

Definition at line 1082 of file dsa.c.

1083 {
1084  size_t i,
1085  j;
1086 
1087  /*
1088  * Note: This gives an inconsistent snapshot as it acquires and releases
1089  * individual locks as it goes...
1090  */
1091 
1094  fprintf(stderr, "dsa_area handle %x:\n", area->control->handle);
1095  fprintf(stderr, " max_total_segment_size: %zu\n",
1097  fprintf(stderr, " total_segment_size: %zu\n",
1098  area->control->total_segment_size);
1099  fprintf(stderr, " refcnt: %d\n", area->control->refcnt);
1100  fprintf(stderr, " pinned: %c\n", area->control->pinned ? 't' : 'f');
1101  fprintf(stderr, " segment bins:\n");
1102  for (i = 0; i < DSA_NUM_SEGMENT_BINS; ++i)
1103  {
1105  {
1106  dsa_segment_index segment_index;
1107 
1108  fprintf(stderr,
1109  " segment bin %zu (at least %d contiguous pages free):\n",
1110  i, 1 << (i - 1));
1111  segment_index = area->control->segment_bins[i];
1112  while (segment_index != DSA_SEGMENT_INDEX_NONE)
1113  {
1114  dsa_segment_map *segment_map;
1115 
1116  segment_map =
1117  get_segment_by_index(area, segment_index);
1118 
1119  fprintf(stderr,
1120  " segment index %zu, usable_pages = %zu, "
1121  "contiguous_pages = %zu, mapped at %p\n",
1122  segment_index,
1123  segment_map->header->usable_pages,
1124  fpm_largest(segment_map->fpm),
1125  segment_map->mapped_address);
1126  segment_index = segment_map->header->next;
1127  }
1128  }
1129  }
1131 
1132  fprintf(stderr, " pools:\n");
1133  for (i = 0; i < DSA_NUM_SIZE_CLASSES; ++i)
1134  {
1135  bool found = false;
1136 
1138  for (j = 0; j < DSA_FULLNESS_CLASSES; ++j)
1139  if (DsaPointerIsValid(area->control->pools[i].spans[j]))
1140  found = true;
1141  if (found)
1142  {
1144  fprintf(stderr, " pool for blocks of span objects:\n");
1145  else if (i == DSA_SCLASS_SPAN_LARGE)
1146  fprintf(stderr, " pool for large object spans:\n");
1147  else
1148  fprintf(stderr,
1149  " pool for size class %zu (object size %hu bytes):\n",
1150  i, dsa_size_classes[i]);
1151  for (j = 0; j < DSA_FULLNESS_CLASSES; ++j)
1152  {
1153  if (!DsaPointerIsValid(area->control->pools[i].spans[j]))
1154  fprintf(stderr, " fullness class %zu is empty\n", j);
1155  else
1156  {
1157  dsa_pointer span_pointer = area->control->pools[i].spans[j];
1158 
1159  fprintf(stderr, " fullness class %zu:\n", j);
1160  while (DsaPointerIsValid(span_pointer))
1161  {
1162  dsa_area_span *span;
1163 
1164  span = dsa_get_address(area, span_pointer);
1165  fprintf(stderr,
1166  " span descriptor at "
1167  DSA_POINTER_FORMAT ", superblock at "
1169  ", pages = %zu, objects free = %hu/%hu\n",
1170  span_pointer, span->start, span->npages,
1171  span->nallocatable, span->nmax);
1172  span_pointer = span->nextspan;
1173  }
1174  }
1175  }
1176  }
1178  }
1179 }
#define DSA_SEGMENT_INDEX_NONE
Definition: dsa.c:128
static void check_for_freed_segments_locked(dsa_area *area)
Definition: dsa.c:2266
size_t dsa_segment_index
Definition: dsa.c:125
static dsa_segment_map * get_segment_by_index(dsa_area *area, dsa_segment_index index)
Definition: dsa.c:1739
#define DSA_NUM_SIZE_CLASSES
Definition: dsa.c:259
#define DSA_FULLNESS_CLASSES
Definition: dsa.c:289
#define DSA_NUM_SEGMENT_BINS
Definition: dsa.c:134
#define DSA_POINTER_FORMAT
Definition: dsa.h:69
#define fpm_largest(fpm)
Definition: freepage.h:88
int j
Definition: isn.c:74
#define fprintf
Definition: port.h:242
size_t total_segment_size
Definition: dsa.c:323
bool pinned
Definition: dsa.c:331
size_t max_total_segment_size
Definition: dsa.c:325
dsa_segment_index segment_bins[DSA_NUM_SEGMENT_BINS]
Definition: dsa.c:319
int refcnt
Definition: dsa.c:329
dsa_handle handle
Definition: dsa.c:315
dsa_pointer spans[DSA_FULLNESS_CLASSES]
Definition: dsa.c:302
dsa_pointer nextspan
Definition: dsa.c:210
dsa_pointer start
Definition: dsa.c:211
uint16 nallocatable
Definition: dsa.c:215
uint16 nmax
Definition: dsa.c:217
size_t npages
Definition: dsa.c:212
dsa_segment_index next
Definition: dsa.c:182
size_t usable_pages
Definition: dsa.c:168
dsa_segment_header * header
Definition: dsa.c:355
char * mapped_address
Definition: dsa.c:354

References check_for_freed_segments_locked(), dsa_area::control, DSA_AREA_LOCK, DSA_FULLNESS_CLASSES, dsa_get_address(), DSA_NUM_SEGMENT_BINS, DSA_NUM_SIZE_CLASSES, DSA_POINTER_FORMAT, DSA_SCLASS_BLOCK_OF_SPANS, DSA_SCLASS_LOCK, DSA_SCLASS_SPAN_LARGE, DSA_SEGMENT_INDEX_NONE, dsa_size_classes, DsaPointerIsValid, dsa_segment_map::fpm, fpm_largest, fprintf, get_segment_by_index(), dsa_area_control::handle, dsa_segment_map::header, i, j, LW_EXCLUSIVE, LWLockAcquire(), LWLockRelease(), dsa_segment_map::mapped_address, dsa_area_control::max_total_segment_size, dsa_area_span::nallocatable, dsa_segment_header::next, dsa_area_span::nextspan, dsa_area_span::nmax, dsa_area_span::npages, dsa_area_control::pinned, dsa_area_control::pools, dsa_area_control::refcnt, dsa_area_control::segment_bins, dsa_area_pool::spans, dsa_area_span::start, dsa_area_control::total_segment_size, and dsa_segment_header::usable_pages.

◆ dsa_free()

void dsa_free ( dsa_area area,
dsa_pointer  dp 
)

Definition at line 833 of file dsa.c.

834 {
835  dsa_segment_map *segment_map;
836  int pageno;
837  dsa_pointer span_pointer;
838  dsa_area_span *span;
839  char *superblock;
840  char *object;
841  size_t size;
842  int size_class;
843 
844  /* Make sure we don't have a stale segment in the slot 'dp' refers to. */
846 
847  /* Locate the object, span and pool. */
848  segment_map = get_segment_by_index(area, DSA_EXTRACT_SEGMENT_NUMBER(dp));
849  pageno = DSA_EXTRACT_OFFSET(dp) / FPM_PAGE_SIZE;
850  span_pointer = segment_map->pagemap[pageno];
851  span = dsa_get_address(area, span_pointer);
852  superblock = dsa_get_address(area, span->start);
853  object = dsa_get_address(area, dp);
854  size_class = span->size_class;
855  size = dsa_size_classes[size_class];
856 
857  /*
858  * Special case for large objects that live in a special span: we return
859  * those pages directly to the free page manager and free the span.
860  */
861  if (span->size_class == DSA_SCLASS_SPAN_LARGE)
862  {
863 
864 #ifdef CLOBBER_FREED_MEMORY
865  memset(object, 0x7f, span->npages * FPM_PAGE_SIZE);
866 #endif
867 
868  /* Give pages back to free page manager. */
870  FreePageManagerPut(segment_map->fpm,
872  span->npages);
873 
874  /* Move segment to appropriate bin if necessary. */
875  rebin_segment(area, segment_map);
877 
878  /* Unlink span. */
880  LW_EXCLUSIVE);
881  unlink_span(area, span);
883  /* Free the span object so it can be reused. */
884  dsa_free(area, span_pointer);
885  return;
886  }
887 
888 #ifdef CLOBBER_FREED_MEMORY
889  memset(object, 0x7f, size);
890 #endif
891 
892  LWLockAcquire(DSA_SCLASS_LOCK(area, size_class), LW_EXCLUSIVE);
893 
894  /* Put the object on the span's freelist. */
895  Assert(object >= superblock);
896  Assert(object < superblock + DSA_SUPERBLOCK_SIZE);
897  Assert((object - superblock) % size == 0);
898  NextFreeObjectIndex(object) = span->firstfree;
899  span->firstfree = (object - superblock) / size;
900  ++span->nallocatable;
901 
902  /*
903  * See if the span needs to moved to a different fullness class, or be
904  * freed so its pages can be given back to the segment.
905  */
906  if (span->nallocatable == 1 && span->fclass == DSA_FULLNESS_CLASSES - 1)
907  {
908  /*
909  * The block was completely full and is located in the
910  * highest-numbered fullness class, which is never scanned for free
911  * chunks. We must move it to the next-lower fullness class.
912  */
913  unlink_span(area, span);
914  add_span_to_fullness_class(area, span, span_pointer,
916 
917  /*
918  * If this is the only span, and there is no active span, then we
919  * should probably move this span to fullness class 1. (Otherwise if
920  * you allocate exactly all the objects in the only span, it moves to
921  * class 3, then you free them all, it moves to 2, and then is given
922  * back, leaving no active span).
923  */
924  }
925  else if (span->nallocatable == span->nmax &&
926  (span->fclass != 1 || span->prevspan != InvalidDsaPointer))
927  {
928  /*
929  * This entire block is free, and it's not the active block for this
930  * size class. Return the memory to the free page manager. We don't
931  * do this for the active block to prevent hysteresis: if we
932  * repeatedly allocate and free the only chunk in the active block, it
933  * will be very inefficient if we deallocate and reallocate the block
934  * every time.
935  */
936  destroy_superblock(area, span_pointer);
937  }
938 
939  LWLockRelease(DSA_SCLASS_LOCK(area, size_class));
940 }
static void check_for_freed_segments(dsa_area *area)
Definition: dsa.c:2230
#define DSA_EXTRACT_SEGMENT_NUMBER(dp)
Definition: dsa.c:119
static void add_span_to_fullness_class(dsa_area *area, dsa_area_span *span, dsa_pointer span_pointer, int fclass)
Definition: dsa.c:1909
#define DSA_SUPERBLOCK_SIZE
Definition: dsa.c:390
#define DSA_EXTRACT_OFFSET(dp)
Definition: dsa.c:122
static void destroy_superblock(dsa_area *area, dsa_pointer span_pointer)
Definition: dsa.c:1817
static void rebin_segment(dsa_area *area, dsa_segment_map *segment_map)
Definition: dsa.c:2294
static void unlink_span(dsa_area *area, dsa_area_span *span)
Definition: dsa.c:1886
#define NextFreeObjectIndex(object)
Definition: dsa.c:225
void FreePageManagerPut(FreePageManager *fpm, Size first_page, Size npages)
Definition: freepage.c:379
uint16 fclass
Definition: dsa.c:218
dsa_pointer prevspan
Definition: dsa.c:209
uint16 size_class
Definition: dsa.c:213
uint16 firstfree
Definition: dsa.c:216

References add_span_to_fullness_class(), Assert(), check_for_freed_segments(), destroy_superblock(), DSA_AREA_LOCK, DSA_EXTRACT_OFFSET, DSA_EXTRACT_SEGMENT_NUMBER, DSA_FULLNESS_CLASSES, dsa_get_address(), DSA_SCLASS_LOCK, DSA_SCLASS_SPAN_LARGE, dsa_size_classes, DSA_SUPERBLOCK_SIZE, dsa_area_span::fclass, dsa_area_span::firstfree, dsa_segment_map::fpm, FPM_PAGE_SIZE, FreePageManagerPut(), get_segment_by_index(), InvalidDsaPointer, LW_EXCLUSIVE, LWLockAcquire(), LWLockRelease(), dsa_area_span::nallocatable, NextFreeObjectIndex, dsa_area_span::nmax, dsa_area_span::npages, dsa_segment_map::pagemap, dsa_area_span::prevspan, rebin_segment(), dsa_area_span::size_class, dsa_area_span::start, and unlink_span().

Referenced by delete_item_from_bucket(), delete_key_from_bucket(), destroy_superblock(), dsa_allocate_extended(), dshash_create(), dshash_destroy(), ExecHashTableDetach(), ExecHashTableDetachBatch(), ExecParallelCleanup(), ExecParallelHashIncreaseNumBatches(), ExecParallelHashIncreaseNumBuckets(), ExecParallelHashRepartitionFirst(), ExecParallelReinitialize(), find_or_make_matching_shared_tupledesc(), pagetable_free(), pgstat_free_entry(), resize(), and tbm_free_shared_area().

◆ dsa_get_address()

void* dsa_get_address ( dsa_area area,
dsa_pointer  dp 
)

Definition at line 949 of file dsa.c.

950 {
952  size_t offset;
953 
954  /* Convert InvalidDsaPointer to NULL. */
955  if (!DsaPointerIsValid(dp))
956  return NULL;
957 
958  /* Process any requests to detach from freed segments. */
960 
961  /* Break the dsa_pointer into its components. */
963  offset = DSA_EXTRACT_OFFSET(dp);
965 
966  /* Check if we need to cause this segment to be mapped in. */
967  if (unlikely(area->segment_maps[index].mapped_address == NULL))
968  {
969  /* Call for effect (we don't need the result). */
971  }
972 
973  return area->segment_maps[index].mapped_address + offset;
974 }
#define unlikely(x)
Definition: c.h:300
#define DSA_MAX_SEGMENTS
Definition: dsa.c:95
Definition: type.h:95

References Assert(), check_for_freed_segments(), DSA_EXTRACT_OFFSET, DSA_EXTRACT_SEGMENT_NUMBER, DSA_MAX_SEGMENTS, DsaPointerIsValid, get_segment_by_index(), dsa_segment_map::mapped_address, dsa_area::segment_maps, and unlikely.

Referenced by add_span_to_fullness_class(), alloc_object(), delete_item_from_bucket(), delete_key_from_bucket(), destroy_superblock(), dsa_allocate_extended(), dsa_dump(), dsa_free(), dsa_trim(), dshash_attach(), dshash_create(), dshash_destroy(), dshash_dump(), dshash_seq_next(), ensure_active_superblock(), ensure_valid_bucket_pointers(), ExecHashTableDetachBatch(), ExecParallelHashEnsureBatchAccessors(), ExecParallelHashFirstTuple(), ExecParallelHashIncreaseNumBatches(), ExecParallelHashIncreaseNumBuckets(), ExecParallelHashJoinSetUpBatches(), ExecParallelHashNextTuple(), ExecParallelHashPopChunkQueue(), ExecParallelHashRepartitionRest(), ExecParallelHashTableAlloc(), ExecParallelHashTableSetCurrentBatch(), ExecParallelHashTupleAlloc(), find_in_bucket(), find_or_make_matching_shared_tupledesc(), init_span(), insert_into_bucket(), insert_item_into_bucket(), lookup_rowtype_tupdesc_internal(), pagetable_allocate(), ParallelQueryMain(), pgstat_build_snapshot(), pgstat_get_entry_ref(), pgstat_init_entry(), pgstat_reinit_entry(), pgstat_reset_matching_entries(), pgstat_write_statsfile(), resize(), SerializeParamExecParams(), share_tupledesc(), shared_record_table_compare(), shared_record_table_hash(), tbm_attach_shared_iterate(), tbm_free_shared_area(), tbm_prepare_shared_iterate(), transfer_first_span(), and unlink_span().

◆ dsa_get_handle()

dsa_handle dsa_get_handle ( dsa_area area)

Definition at line 507 of file dsa.c.

508 {
510  return area->control->handle;
511 }

References Assert(), dsa_area::control, DSA_HANDLE_INVALID, and dsa_area_control::handle.

Referenced by logicalrep_launcher_attach_dshmem().

◆ dsa_minimum_size()

size_t dsa_minimum_size ( void  )

Definition at line 1186 of file dsa.c.

1187 {
1188  size_t size;
1189  int pages = 0;
1190 
1191  size = MAXALIGN(sizeof(dsa_area_control)) +
1192  MAXALIGN(sizeof(FreePageManager));
1193 
1194  /* Figure out how many pages we need, including the page map... */
1195  while (((size + FPM_PAGE_SIZE - 1) / FPM_PAGE_SIZE) > pages)
1196  {
1197  ++pages;
1198  size += sizeof(dsa_pointer);
1199  }
1200 
1201  return pages * FPM_PAGE_SIZE;
1202 }
#define MAXALIGN(LEN)
Definition: c.h:800

References FPM_PAGE_SIZE, and MAXALIGN.

Referenced by create_internal(), ExecInitParallelPlan(), and pgstat_dsa_init_size().

◆ dsa_on_dsm_detach_release_in_place()

void dsa_on_dsm_detach_release_in_place ( dsm_segment segment,
Datum  place 
)

Definition at line 585 of file dsa.c.

586 {
588 }
void dsa_release_in_place(void *place)
Definition: dsa.c:614
static Pointer DatumGetPointer(Datum X)
Definition: postgres.h:312

References DatumGetPointer(), and dsa_release_in_place().

Referenced by dsa_attach(), dsa_attach_in_place(), dsa_create(), and dsa_create_in_place().

◆ dsa_on_shmem_exit_release_in_place()

void dsa_on_shmem_exit_release_in_place ( int  code,
Datum  place 
)

Definition at line 599 of file dsa.c.

600 {
602 }

References DatumGetPointer(), and dsa_release_in_place().

◆ dsa_pin()

void dsa_pin ( dsa_area area)

Definition at line 982 of file dsa.c.

983 {
985  if (area->control->pinned)
986  {
988  elog(ERROR, "dsa_area already pinned");
989  }
990  area->control->pinned = true;
991  ++area->control->refcnt;
993 }

References dsa_area::control, DSA_AREA_LOCK, elog(), ERROR, LW_EXCLUSIVE, LWLockAcquire(), LWLockRelease(), dsa_area_control::pinned, and dsa_area_control::refcnt.

Referenced by logicalrep_launcher_attach_dshmem(), and StatsShmemInit().

◆ dsa_pin_mapping()

void dsa_pin_mapping ( dsa_area area)

Definition at line 644 of file dsa.c.

645 {
646  int i;
647 
648  Assert(!area->mapping_pinned);
649  area->mapping_pinned = true;
650 
651  for (i = 0; i <= area->high_segment_index; ++i)
652  if (area->segment_maps[i].segment != NULL)
654 }
void dsm_pin_mapping(dsm_segment *seg)
Definition: dsm.c:888
bool mapping_pinned
Definition: dsa.c:372

References Assert(), dsm_pin_mapping(), dsa_area::high_segment_index, i, dsa_area::mapping_pinned, dsa_segment_map::segment, and dsa_area::segment_maps.

Referenced by AttachSession(), GetSessionDsmHandle(), logicalrep_launcher_attach_dshmem(), and pgstat_attach_shmem().

◆ dsa_release_in_place()

void dsa_release_in_place ( void *  place)

Definition at line 614 of file dsa.c.

615 {
616  dsa_area_control *control = (dsa_area_control *) place;
617  int i;
618 
619  LWLockAcquire(&control->lock, LW_EXCLUSIVE);
620  Assert(control->segment_header.magic ==
621  (DSA_SEGMENT_HEADER_MAGIC ^ control->handle ^ 0));
622  Assert(control->refcnt > 0);
623  if (--control->refcnt == 0)
624  {
625  for (i = 0; i <= control->high_segment_index; ++i)
626  {
627  dsm_handle handle;
628 
629  handle = control->segment_handles[i];
630  if (handle != DSM_HANDLE_INVALID)
631  dsm_unpin_segment(handle);
632  }
633  }
634  LWLockRelease(&control->lock);
635 }
#define DSA_SEGMENT_HEADER_MAGIC
Definition: dsa.c:112
void dsm_unpin_segment(dsm_handle handle)
Definition: dsm.c:960
uint32 dsm_handle
Definition: dsm_impl.h:55
dsa_segment_header segment_header
Definition: dsa.c:313
dsa_segment_index high_segment_index
Definition: dsa.c:327
LWLock lock
Definition: dsa.c:337
dsm_handle segment_handles[DSA_MAX_SEGMENTS]
Definition: dsa.c:317
uint32 magic
Definition: dsa.c:166

References Assert(), DSA_SEGMENT_HEADER_MAGIC, DSM_HANDLE_INVALID, dsm_unpin_segment(), dsa_area_control::handle, dsa_area_control::high_segment_index, i, dsa_area_control::lock, LW_EXCLUSIVE, LWLockAcquire(), LWLockRelease(), dsa_segment_header::magic, dsa_area_control::refcnt, dsa_area_control::segment_handles, and dsa_area_control::segment_header.

Referenced by dsa_on_dsm_detach_release_in_place(), and dsa_on_shmem_exit_release_in_place().

◆ dsa_set_size_limit()

void dsa_set_size_limit ( dsa_area area,
size_t  limit 
)

◆ dsa_trim()

void dsa_trim ( dsa_area area)

Definition at line 1037 of file dsa.c.

1038 {
1039  int size_class;
1040 
1041  /*
1042  * Trim in reverse pool order so we get to the spans-of-spans last, just
1043  * in case any become entirely free while processing all the other pools.
1044  */
1045  for (size_class = DSA_NUM_SIZE_CLASSES - 1; size_class >= 0; --size_class)
1046  {
1047  dsa_area_pool *pool = &area->control->pools[size_class];
1048  dsa_pointer span_pointer;
1049 
1050  if (size_class == DSA_SCLASS_SPAN_LARGE)
1051  {
1052  /* Large object frees give back segments aggressively already. */
1053  continue;
1054  }
1055 
1056  /*
1057  * Search fullness class 1 only. That is where we expect to find an
1058  * entirely empty superblock (entirely empty superblocks in other
1059  * fullness classes are returned to the free page map by dsa_free).
1060  */
1061  LWLockAcquire(DSA_SCLASS_LOCK(area, size_class), LW_EXCLUSIVE);
1062  span_pointer = pool->spans[1];
1063  while (DsaPointerIsValid(span_pointer))
1064  {
1065  dsa_area_span *span = dsa_get_address(area, span_pointer);
1066  dsa_pointer next = span->nextspan;
1067 
1068  if (span->nallocatable == span->nmax)
1069  destroy_superblock(area, span_pointer);
1070 
1071  span_pointer = next;
1072  }
1073  LWLockRelease(DSA_SCLASS_LOCK(area, size_class));
1074  }
1075 }
static int32 next
Definition: blutils.c:219

References dsa_area::control, destroy_superblock(), dsa_get_address(), DSA_NUM_SIZE_CLASSES, DSA_SCLASS_LOCK, DSA_SCLASS_SPAN_LARGE, DsaPointerIsValid, LW_EXCLUSIVE, LWLockAcquire(), LWLockRelease(), dsa_area_span::nallocatable, next, dsa_area_span::nextspan, dsa_area_span::nmax, dsa_area_control::pools, and dsa_area_pool::spans.

◆ dsa_unpin()

void dsa_unpin ( dsa_area area)

Definition at line 1001 of file dsa.c.

1002 {
1004  Assert(area->control->refcnt > 1);
1005  if (!area->control->pinned)
1006  {
1008  elog(ERROR, "dsa_area not pinned");
1009  }
1010  area->control->pinned = false;
1011  --area->control->refcnt;
1013 }

References Assert(), dsa_area::control, DSA_AREA_LOCK, elog(), ERROR, LW_EXCLUSIVE, LWLockAcquire(), LWLockRelease(), dsa_area_control::pinned, and dsa_area_control::refcnt.