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dsa.h File Reference
#include "port/atomics.h"
#include "storage/dsm.h"
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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" PRIx64
 
#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 DSA_OFFSET_WIDTH   40 /* 1024 segments of size up to 1TB */
 
#define DSA_DEFAULT_INIT_SEGMENT_SIZE   ((size_t) (1 * 1024 * 1024))
 
#define DSA_MIN_SEGMENT_SIZE   ((size_t) (256 * 1024L))
 
#define DSA_MAX_SEGMENT_SIZE   ((size_t) 1 << DSA_OFFSET_WIDTH)
 
#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_create(tranch_id)
 
#define dsa_create_in_place(place, size, tranch_id, segment)
 
#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_ext (int tranche_id, size_t init_segment_size, size_t max_segment_size)
 
dsa_areadsa_create_in_place_ext (void *place, size_t size, int tranche_id, dsm_segment *segment, size_t init_segment_size, size_t max_segment_size)
 
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)
 
size_t dsa_get_total_size (dsa_area *area)
 
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 109 of file dsa.h.

◆ dsa_allocate0

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

Definition at line 113 of file dsa.h.

◆ dsa_create

#define dsa_create (   tranch_id)
Value:
#define DSA_DEFAULT_INIT_SEGMENT_SIZE
Definition: dsa.h:97
#define DSA_MAX_SEGMENT_SIZE
Definition: dsa.h:103
dsa_area * dsa_create_ext(int tranche_id, size_t init_segment_size, size_t max_segment_size)
Definition: dsa.c:421

Definition at line 117 of file dsa.h.

◆ dsa_create_in_place

#define dsa_create_in_place (   place,
  size,
  tranch_id,
  segment 
)
Value:
dsa_create_in_place_ext(place, size, tranch_id, segment, \
dsa_area * dsa_create_in_place_ext(void *place, size_t size, int tranche_id, dsm_segment *segment, size_t init_segment_size, size_t max_segment_size)
Definition: dsa.c:471
static pg_noinline void Size size
Definition: slab.c:607

Definition at line 122 of file dsa.h.

◆ DSA_DEFAULT_INIT_SEGMENT_SIZE

#define DSA_DEFAULT_INIT_SEGMENT_SIZE   ((size_t) (1 * 1024 * 1024))

Definition at line 97 of file dsa.h.

◆ DSA_HANDLE_INVALID

#define DSA_HANDLE_INVALID   ((dsa_handle) DSM_HANDLE_INVALID)

Definition at line 139 of file dsa.h.

◆ DSA_MAX_SEGMENT_SIZE

#define DSA_MAX_SEGMENT_SIZE   ((size_t) 1 << DSA_OFFSET_WIDTH)

Definition at line 103 of file dsa.h.

◆ DSA_MIN_SEGMENT_SIZE

#define DSA_MIN_SEGMENT_SIZE   ((size_t) (256 * 1024L))

Definition at line 100 of file dsa.h.

◆ DSA_OFFSET_WIDTH

#define DSA_OFFSET_WIDTH   40 /* 1024 segments of size up to 1TB */

Definition at line 88 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" PRIx64

Definition at line 69 of file dsa.h.

◆ DsaPointerIsValid

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

Definition at line 106 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 136 of file dsa.h.

◆ 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 671 of file dsa.c.

672 {
673  uint16 size_class;
674  dsa_pointer start_pointer;
675  dsa_segment_map *segment_map;
676  dsa_pointer result;
677 
678  Assert(size > 0);
679 
680  /* Sanity check on huge individual allocation size. */
681  if (((flags & DSA_ALLOC_HUGE) != 0 && !AllocHugeSizeIsValid(size)) ||
682  ((flags & DSA_ALLOC_HUGE) == 0 && !AllocSizeIsValid(size)))
683  elog(ERROR, "invalid DSA memory alloc request size %zu", size);
684 
685  /*
686  * If bigger than the largest size class, just grab a run of pages from
687  * the free page manager, instead of allocating an object from a pool.
688  * There will still be a span, but it's a special class of span that
689  * manages this whole allocation and simply gives all pages back to the
690  * free page manager when dsa_free is called.
691  */
693  {
694  size_t npages = fpm_size_to_pages(size);
695  size_t first_page;
696  dsa_pointer span_pointer;
698 
699  /* Obtain a span object. */
700  span_pointer = alloc_object(area, DSA_SCLASS_BLOCK_OF_SPANS);
701  if (!DsaPointerIsValid(span_pointer))
702  {
703  /* Raise error unless asked not to. */
704  if ((flags & DSA_ALLOC_NO_OOM) == 0)
705  ereport(ERROR,
706  (errcode(ERRCODE_OUT_OF_MEMORY),
707  errmsg("out of memory"),
708  errdetail("Failed on DSA request of size %zu.",
709  size)));
710  return InvalidDsaPointer;
711  }
712 
714 
715  /* Find a segment from which to allocate. */
716  segment_map = get_best_segment(area, npages);
717  if (segment_map == NULL)
718  segment_map = make_new_segment(area, npages);
719  if (segment_map == NULL)
720  {
721  /* Can't make any more segments: game over. */
723  dsa_free(area, span_pointer);
724 
725  /* Raise error unless asked not to. */
726  if ((flags & DSA_ALLOC_NO_OOM) == 0)
727  ereport(ERROR,
728  (errcode(ERRCODE_OUT_OF_MEMORY),
729  errmsg("out of memory"),
730  errdetail("Failed on DSA request of size %zu.",
731  size)));
732  return InvalidDsaPointer;
733  }
734 
735  /*
736  * Ask the free page manager for a run of pages. This should always
737  * succeed, since both get_best_segment and make_new_segment should
738  * only return a non-NULL pointer if it actually contains enough
739  * contiguous freespace. If it does fail, something in our backend
740  * private state is out of whack, so use FATAL to kill the process.
741  */
742  if (!FreePageManagerGet(segment_map->fpm, npages, &first_page))
743  elog(FATAL,
744  "dsa_allocate could not find %zu free pages", npages);
746 
747  start_pointer = DSA_MAKE_POINTER(get_segment_index(area, segment_map),
748  first_page * FPM_PAGE_SIZE);
749 
750  /* Initialize span and pagemap. */
752  LW_EXCLUSIVE);
753  init_span(area, span_pointer, pool, start_pointer, npages,
755  segment_map->pagemap[first_page] = span_pointer;
757 
758  /* Zero-initialize the memory if requested. */
759  if ((flags & DSA_ALLOC_ZERO) != 0)
760  memset(dsa_get_address(area, start_pointer), 0, size);
761 
762  return start_pointer;
763  }
764 
765  /* Map allocation to a size class. */
767  {
768  int mapidx;
769 
770  /* For smaller sizes we have a lookup table... */
771  mapidx = ((size + DSA_SIZE_CLASS_MAP_QUANTUM - 1) /
773  size_class = dsa_size_class_map[mapidx];
774  }
775  else
776  {
777  uint16 min;
778  uint16 max;
779 
780  /* ... and for the rest we search by binary chop. */
782  max = lengthof(dsa_size_classes) - 1;
783 
784  while (min < max)
785  {
786  uint16 mid = (min + max) / 2;
787  uint16 class_size = dsa_size_classes[mid];
788 
789  if (class_size < size)
790  min = mid + 1;
791  else
792  max = mid;
793  }
794 
795  size_class = min;
796  }
797  Assert(size <= dsa_size_classes[size_class]);
798  Assert(size_class == 0 || size > dsa_size_classes[size_class - 1]);
799 
800  /* Attempt to allocate an object from the appropriate pool. */
801  result = alloc_object(area, size_class);
802 
803  /* Check for failure to allocate. */
804  if (!DsaPointerIsValid(result))
805  {
806  /* Raise error unless asked not to. */
807  if ((flags & DSA_ALLOC_NO_OOM) == 0)
808  ereport(ERROR,
809  (errcode(ERRCODE_OUT_OF_MEMORY),
810  errmsg("out of memory"),
811  errdetail("Failed on DSA request of size %zu.", size)));
812  return InvalidDsaPointer;
813  }
814 
815  /* Zero-initialize the memory if requested. */
816  if ((flags & DSA_ALLOC_ZERO) != 0)
817  memset(dsa_get_address(area, result), 0, size);
818 
819  return result;
820 }
#define Assert(condition)
Definition: c.h:812
uint16_t uint16
Definition: c.h:484
#define lengthof(array)
Definition: c.h:742
static const uint16 dsa_size_classes[]
Definition: dsa.c:225
#define DSA_AREA_LOCK(area)
Definition: dsa.c:132
#define DSA_MAKE_POINTER(segment_number, offset)
Definition: dsa.c:92
#define get_segment_index(area, segment_map_ptr)
Definition: dsa.c:379
static dsa_pointer alloc_object(dsa_area *area, int size_class)
Definition: dsa.c:1472
#define DSA_SIZE_CLASS_MAP_QUANTUM
Definition: dsa.c:258
static const uint8 dsa_size_class_map[]
Definition: dsa.c:248
static dsa_segment_map * make_new_segment(dsa_area *area, size_t requested_pages)
Definition: dsa.c:2081
void * dsa_get_address(dsa_area *area, dsa_pointer dp)
Definition: dsa.c:942
#define DSA_SCLASS_LOCK(area, sclass)
Definition: dsa.c:133
#define DSA_SCLASS_BLOCK_OF_SPANS
Definition: dsa.c:239
#define DSA_SCLASS_SPAN_LARGE
Definition: dsa.c:240
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:1377
static dsa_segment_map * get_best_segment(dsa_area *area, size_t npages)
Definition: dsa.c:2010
void dsa_free(dsa_area *area, dsa_pointer dp)
Definition: dsa.c:826
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:106
#define DSA_ALLOC_HUGE
Definition: dsa.h:73
#define DSA_ALLOC_ZERO
Definition: dsa.h:75
int errdetail(const char *fmt,...)
Definition: elog.c:1203
int errcode(int sqlerrcode)
Definition: elog.c:853
int errmsg(const char *fmt,...)
Definition: elog.c:1070
#define FATAL
Definition: elog.h:41
#define ERROR
Definition: elog.h:39
#define elog(elevel,...)
Definition: elog.h:225
#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
bool LWLockAcquire(LWLock *lock, LWLockMode mode)
Definition: lwlock.c:1168
void LWLockRelease(LWLock *lock)
Definition: lwlock.c:1781
@ LW_EXCLUSIVE
Definition: lwlock.h:114
#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:298
dsa_area_control * control
Definition: dsa.c:350
FreePageManager * fpm
Definition: dsa.c:337
dsa_pointer * pagemap
Definition: dsa.c:338

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, dsa_area_control::pools, and size.

Referenced by dshash_create(), and pagetable_allocate().

◆ dsa_attach()

dsa_area* dsa_attach ( dsa_handle  handle)

Definition at line 510 of file dsa.c.

511 {
512  dsm_segment *segment;
513  dsa_area *area;
514 
515  /*
516  * An area handle is really a DSM segment handle for the first segment, so
517  * we go ahead and attach to that.
518  */
519  segment = dsm_attach(handle);
520  if (segment == NULL)
521  ereport(ERROR,
522  (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
523  errmsg("could not attach to dynamic shared area")));
524 
525  area = attach_internal(dsm_segment_address(segment), segment, handle);
526 
527  /* Clean up when the control segment detaches. */
530 
531  return area;
532 }
void dsa_on_dsm_detach_release_in_place(dsm_segment *segment, Datum place)
Definition: dsa.c:576
static dsa_area * attach_internal(void *place, dsm_segment *segment, dsa_handle handle)
Definition: dsa.c:1326
void * dsm_segment_address(dsm_segment *seg)
Definition: dsm.c:1095
void on_dsm_detach(dsm_segment *seg, on_dsm_detach_callback function, Datum arg)
Definition: dsm.c:1132
dsm_segment * dsm_attach(dsm_handle h)
Definition: dsm.c:665
static Datum PointerGetDatum(const void *X)
Definition: postgres.h:322
Definition: dsa.c:348

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 init_dsm_registry(), logicalrep_launcher_attach_dshmem(), and TidStoreAttach().

◆ dsa_attach_in_place()

dsa_area* dsa_attach_in_place ( void *  place,
dsm_segment segment 
)

Definition at line 545 of file dsa.c.

546 {
547  dsa_area *area;
548 
549  area = attach_internal(place, NULL, DSA_HANDLE_INVALID);
550 
551  /*
552  * Clean up when the control segment detaches, if a containing DSM segment
553  * was provided.
554  */
555  if (segment != NULL)
557  PointerGetDatum(place));
558 
559  return area;
560 }
#define DSA_HANDLE_INVALID
Definition: dsa.h:139

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_ext()

dsa_area* dsa_create_ext ( int  tranche_id,
size_t  init_segment_size,
size_t  max_segment_size 
)

Definition at line 421 of file dsa.c.

422 {
423  dsm_segment *segment;
424  dsa_area *area;
425 
426  /*
427  * Create the DSM segment that will hold the shared control object and the
428  * first segment of usable space.
429  */
430  segment = dsm_create(init_segment_size, 0);
431 
432  /*
433  * All segments backing this area are pinned, so that DSA can explicitly
434  * control their lifetime (otherwise a newly created segment belonging to
435  * this area might be freed when the only backend that happens to have it
436  * mapped in ends, corrupting the area).
437  */
438  dsm_pin_segment(segment);
439 
440  /* Create a new DSA area with the control object in this segment. */
441  area = create_internal(dsm_segment_address(segment),
442  init_segment_size,
443  tranche_id,
444  dsm_segment_handle(segment), segment,
445  init_segment_size, max_segment_size);
446 
447  /* Clean up when the control segment detaches. */
450 
451  return area;
452 }
static dsa_area * create_internal(void *place, size_t size, int tranche_id, dsm_handle control_handle, dsm_segment *control_segment, size_t init_segment_size, size_t max_segment_size)
Definition: dsa.c:1218
dsm_handle dsm_segment_handle(dsm_segment *seg)
Definition: dsm.c:1123
dsm_segment * dsm_create(Size size, int flags)
Definition: dsm.c:516
void dsm_pin_segment(dsm_segment *seg)
Definition: dsm.c:955

References create_internal(), 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 TidStoreCreateShared().

◆ dsa_create_in_place_ext()

dsa_area* dsa_create_in_place_ext ( void *  place,
size_t  size,
int  tranche_id,
dsm_segment segment,
size_t  init_segment_size,
size_t  max_segment_size 
)

Definition at line 471 of file dsa.c.

474 {
475  dsa_area *area;
476 
477  area = create_internal(place, size, tranche_id,
478  DSM_HANDLE_INVALID, NULL,
479  init_segment_size, max_segment_size);
480 
481  /*
482  * Clean up when the control segment detaches, if a containing DSM segment
483  * was provided.
484  */
485  if (segment != NULL)
487  PointerGetDatum(place));
488 
489  return area;
490 }
#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(), PointerGetDatum(), and size.

◆ dsa_detach()

void dsa_detach ( dsa_area area)

Definition at line 1952 of file dsa.c.

1953 {
1954  int i;
1955 
1956  /* Detach from all segments. */
1957  for (i = 0; i <= area->high_segment_index; ++i)
1958  if (area->segment_maps[i].segment != NULL)
1959  dsm_detach(area->segment_maps[i].segment);
1960 
1961  /*
1962  * Note that 'detaching' (= detaching from DSM segments) doesn't include
1963  * 'releasing' (= adjusting the reference count). It would be nice to
1964  * combine these operations, but client code might never get around to
1965  * calling dsa_detach because of an error path, and a detach hook on any
1966  * particular segment is too late to detach other segments in the area
1967  * without risking a 'leak' warning in the non-error path.
1968  */
1969 
1970  /* Free the backend-local area object. */
1971  pfree(area);
1972 }
void dsm_detach(dsm_segment *seg)
Definition: dsm.c:803
int i
Definition: isn.c:72
void pfree(void *pointer)
Definition: mcxt.c:1521
dsa_segment_map segment_maps[DSA_MAX_SEGMENTS]
Definition: dsa.c:366
dsa_segment_index high_segment_index
Definition: dsa.c:369
dsm_segment * segment
Definition: dsa.c:334

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(), StatsShmemInit(), test_basic(), test_dsa_basic(), test_dsa_resowners(), test_empty(), test_random(), TidStoreDestroy(), and TidStoreDetach().

◆ dsa_dump()

void dsa_dump ( dsa_area area)

Definition at line 1088 of file dsa.c.

1089 {
1090  size_t i,
1091  j;
1092 
1093  /*
1094  * Note: This gives an inconsistent snapshot as it acquires and releases
1095  * individual locks as it goes...
1096  */
1097 
1100  fprintf(stderr, "dsa_area handle %x:\n", area->control->handle);
1101  fprintf(stderr, " max_total_segment_size: %zu\n",
1103  fprintf(stderr, " total_segment_size: %zu\n",
1104  area->control->total_segment_size);
1105  fprintf(stderr, " refcnt: %d\n", area->control->refcnt);
1106  fprintf(stderr, " pinned: %c\n", area->control->pinned ? 't' : 'f');
1107  fprintf(stderr, " segment bins:\n");
1108  for (i = 0; i < DSA_NUM_SEGMENT_BINS; ++i)
1109  {
1111  {
1112  dsa_segment_index segment_index;
1113 
1114  if (i == 0)
1115  fprintf(stderr,
1116  " segment bin %zu (no contiguous free pages):\n", i);
1117  else
1118  fprintf(stderr,
1119  " segment bin %zu (at least %d contiguous pages free):\n",
1120  i, 1 << (i - 1));
1121  segment_index = area->control->segment_bins[i];
1122  while (segment_index != DSA_SEGMENT_INDEX_NONE)
1123  {
1124  dsa_segment_map *segment_map;
1125 
1126  segment_map =
1127  get_segment_by_index(area, segment_index);
1128 
1129  fprintf(stderr,
1130  " segment index %zu, usable_pages = %zu, "
1131  "contiguous_pages = %zu, mapped at %p\n",
1132  segment_index,
1133  segment_map->header->usable_pages,
1134  fpm_largest(segment_map->fpm),
1135  segment_map->mapped_address);
1136  segment_index = segment_map->header->next;
1137  }
1138  }
1139  }
1141 
1142  fprintf(stderr, " pools:\n");
1143  for (i = 0; i < DSA_NUM_SIZE_CLASSES; ++i)
1144  {
1145  bool found = false;
1146 
1148  for (j = 0; j < DSA_FULLNESS_CLASSES; ++j)
1149  if (DsaPointerIsValid(area->control->pools[i].spans[j]))
1150  found = true;
1151  if (found)
1152  {
1154  fprintf(stderr, " pool for blocks of span objects:\n");
1155  else if (i == DSA_SCLASS_SPAN_LARGE)
1156  fprintf(stderr, " pool for large object spans:\n");
1157  else
1158  fprintf(stderr,
1159  " pool for size class %zu (object size %hu bytes):\n",
1160  i, dsa_size_classes[i]);
1161  for (j = 0; j < DSA_FULLNESS_CLASSES; ++j)
1162  {
1163  if (!DsaPointerIsValid(area->control->pools[i].spans[j]))
1164  fprintf(stderr, " fullness class %zu is empty\n", j);
1165  else
1166  {
1167  dsa_pointer span_pointer = area->control->pools[i].spans[j];
1168 
1169  fprintf(stderr, " fullness class %zu:\n", j);
1170  while (DsaPointerIsValid(span_pointer))
1171  {
1172  dsa_area_span *span;
1173 
1174  span = dsa_get_address(area, span_pointer);
1175  fprintf(stderr,
1176  " span descriptor at "
1177  DSA_POINTER_FORMAT ", superblock at "
1179  ", pages = %zu, objects free = %hu/%hu\n",
1180  span_pointer, span->start, span->npages,
1181  span->nallocatable, span->nmax);
1182  span_pointer = span->nextspan;
1183  }
1184  }
1185  }
1186  }
1188  }
1189 }
#define DSA_SEGMENT_INDEX_NONE
Definition: dsa.c:105
static void check_for_freed_segments_locked(dsa_area *area)
Definition: dsa.c:2288
size_t dsa_segment_index
Definition: dsa.c:102
static dsa_segment_map * get_segment_by_index(dsa_area *area, dsa_segment_index index)
Definition: dsa.c:1757
#define DSA_NUM_SIZE_CLASSES
Definition: dsa.c:236
#define DSA_FULLNESS_CLASSES
Definition: dsa.c:266
#define DSA_NUM_SEGMENT_BINS
Definition: dsa.c:111
#define DSA_POINTER_FORMAT
Definition: dsa.h:69
#define fpm_largest(fpm)
Definition: freepage.h:88
int j
Definition: isn.c:73
#define fprintf
Definition: port.h:242
size_t total_segment_size
Definition: dsa.c:304
bool pinned
Definition: dsa.c:312
size_t max_total_segment_size
Definition: dsa.c:306
dsa_segment_index segment_bins[DSA_NUM_SEGMENT_BINS]
Definition: dsa.c:296
int refcnt
Definition: dsa.c:310
dsa_handle handle
Definition: dsa.c:292
dsa_pointer spans[DSA_FULLNESS_CLASSES]
Definition: dsa.c:279
dsa_pointer nextspan
Definition: dsa.c:187
dsa_pointer start
Definition: dsa.c:188
uint16 nallocatable
Definition: dsa.c:192
uint16 nmax
Definition: dsa.c:194
size_t npages
Definition: dsa.c:189
dsa_segment_index next
Definition: dsa.c:159
size_t usable_pages
Definition: dsa.c:145
dsa_segment_header * header
Definition: dsa.c:336
char * mapped_address
Definition: dsa.c:335

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 826 of file dsa.c.

827 {
828  dsa_segment_map *segment_map;
829  int pageno;
830  dsa_pointer span_pointer;
831  dsa_area_span *span;
832  char *superblock;
833  char *object;
834  size_t size;
835  int size_class;
836 
837  /* Make sure we don't have a stale segment in the slot 'dp' refers to. */
839 
840  /* Locate the object, span and pool. */
841  segment_map = get_segment_by_index(area, DSA_EXTRACT_SEGMENT_NUMBER(dp));
842  pageno = DSA_EXTRACT_OFFSET(dp) / FPM_PAGE_SIZE;
843  span_pointer = segment_map->pagemap[pageno];
844  span = dsa_get_address(area, span_pointer);
845  superblock = dsa_get_address(area, span->start);
846  object = dsa_get_address(area, dp);
847  size_class = span->size_class;
848  size = dsa_size_classes[size_class];
849 
850  /*
851  * Special case for large objects that live in a special span: we return
852  * those pages directly to the free page manager and free the span.
853  */
854  if (span->size_class == DSA_SCLASS_SPAN_LARGE)
855  {
856 
857 #ifdef CLOBBER_FREED_MEMORY
858  memset(object, 0x7f, span->npages * FPM_PAGE_SIZE);
859 #endif
860 
861  /* Give pages back to free page manager. */
863  FreePageManagerPut(segment_map->fpm,
865  span->npages);
866 
867  /* Move segment to appropriate bin if necessary. */
868  rebin_segment(area, segment_map);
870 
871  /* Unlink span. */
873  LW_EXCLUSIVE);
874  unlink_span(area, span);
876  /* Free the span object so it can be reused. */
877  dsa_free(area, span_pointer);
878  return;
879  }
880 
881 #ifdef CLOBBER_FREED_MEMORY
882  memset(object, 0x7f, size);
883 #endif
884 
885  LWLockAcquire(DSA_SCLASS_LOCK(area, size_class), LW_EXCLUSIVE);
886 
887  /* Put the object on the span's freelist. */
888  Assert(object >= superblock);
889  Assert(object < superblock + DSA_SUPERBLOCK_SIZE);
890  Assert((object - superblock) % size == 0);
891  NextFreeObjectIndex(object) = span->firstfree;
892  span->firstfree = (object - superblock) / size;
893  ++span->nallocatable;
894 
895  /*
896  * See if the span needs to moved to a different fullness class, or be
897  * freed so its pages can be given back to the segment.
898  */
899  if (span->nallocatable == 1 && span->fclass == DSA_FULLNESS_CLASSES - 1)
900  {
901  /*
902  * The block was completely full and is located in the
903  * highest-numbered fullness class, which is never scanned for free
904  * chunks. We must move it to the next-lower fullness class.
905  */
906  unlink_span(area, span);
907  add_span_to_fullness_class(area, span, span_pointer,
909 
910  /*
911  * If this is the only span, and there is no active span, then we
912  * should probably move this span to fullness class 1. (Otherwise if
913  * you allocate exactly all the objects in the only span, it moves to
914  * class 3, then you free them all, it moves to 2, and then is given
915  * back, leaving no active span).
916  */
917  }
918  else if (span->nallocatable == span->nmax &&
919  (span->fclass != 1 || span->prevspan != InvalidDsaPointer))
920  {
921  /*
922  * This entire block is free, and it's not the active block for this
923  * size class. Return the memory to the free page manager. We don't
924  * do this for the active block to prevent hysteresis: if we
925  * repeatedly allocate and free the only chunk in the active block, it
926  * will be very inefficient if we deallocate and reallocate the block
927  * every time.
928  */
929  destroy_superblock(area, span_pointer);
930  }
931 
932  LWLockRelease(DSA_SCLASS_LOCK(area, size_class));
933 }
static void check_for_freed_segments(dsa_area *area)
Definition: dsa.c:2252
#define DSA_EXTRACT_SEGMENT_NUMBER(dp)
Definition: dsa.c:96
static void add_span_to_fullness_class(dsa_area *area, dsa_area_span *span, dsa_pointer span_pointer, int fclass)
Definition: dsa.c:1929
#define DSA_SUPERBLOCK_SIZE
Definition: dsa.c:376
#define DSA_EXTRACT_OFFSET(dp)
Definition: dsa.c:99
static void destroy_superblock(dsa_area *area, dsa_pointer span_pointer)
Definition: dsa.c:1837
static void rebin_segment(dsa_area *area, dsa_segment_map *segment_map)
Definition: dsa.c:2316
static void unlink_span(dsa_area *area, dsa_area_span *span)
Definition: dsa.c:1906
#define NextFreeObjectIndex(object)
Definition: dsa.c:202
void FreePageManagerPut(FreePageManager *fpm, Size first_page, Size npages)
Definition: freepage.c:379
uint16 fclass
Definition: dsa.c:195
dsa_pointer prevspan
Definition: dsa.c:186
uint16 size_class
Definition: dsa.c:190
uint16 firstfree
Definition: dsa.c:193

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(), size, 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(), RT_FREE(), RT_FREE_LEAF(), RT_FREE_NODE(), tbm_free_shared_area(), test_dsa_basic(), and test_dsa_resowners().

◆ dsa_get_address()

void* dsa_get_address ( dsa_area area,
dsa_pointer  dp 
)

Definition at line 942 of file dsa.c.

943 {
945  size_t offset;
946 
947  /* Convert InvalidDsaPointer to NULL. */
948  if (!DsaPointerIsValid(dp))
949  return NULL;
950 
951  /* Process any requests to detach from freed segments. */
953 
954  /* Break the dsa_pointer into its components. */
956  offset = DSA_EXTRACT_OFFSET(dp);
958 
959  /* Check if we need to cause this segment to be mapped in. */
960  if (unlikely(area->segment_maps[index].mapped_address == NULL))
961  {
962  /* Call for effect (we don't need the result). */
964  }
965 
966  return area->segment_maps[index].mapped_address + offset;
967 }
#define unlikely(x)
Definition: c.h:330
#define DSA_MAX_SEGMENTS
Definition: dsa.c:75
Definition: type.h:96

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(), RT_PTR_SET_LOCAL(), SerializeParamExecParams(), share_tupledesc(), shared_record_table_compare(), shared_record_table_hash(), tbm_attach_shared_iterate(), tbm_free_shared_area(), tbm_prepare_shared_iterate(), test_dsa_basic(), test_dsa_resowners(), transfer_first_span(), and unlink_span().

◆ dsa_get_handle()

dsa_handle dsa_get_handle ( dsa_area area)

◆ dsa_get_total_size()

size_t dsa_get_total_size ( dsa_area area)

Definition at line 1027 of file dsa.c.

1028 {
1029  size_t size;
1030 
1032  size = area->control->total_segment_size;
1034 
1035  return size;
1036 }

References dsa_area::control, DSA_AREA_LOCK, LW_EXCLUSIVE, LWLockAcquire(), LWLockRelease(), size, and dsa_area_control::total_segment_size.

Referenced by RT_MEMORY_USAGE().

◆ dsa_minimum_size()

size_t dsa_minimum_size ( void  )

Definition at line 1196 of file dsa.c.

1197 {
1198  size_t size;
1199  int pages = 0;
1200 
1201  size = MAXALIGN(sizeof(dsa_area_control)) +
1202  MAXALIGN(sizeof(FreePageManager));
1203 
1204  /* Figure out how many pages we need, including the page map... */
1205  while (((size + FPM_PAGE_SIZE - 1) / FPM_PAGE_SIZE) > pages)
1206  {
1207  ++pages;
1208  size += sizeof(dsa_pointer);
1209  }
1210 
1211  return pages * FPM_PAGE_SIZE;
1212 }
#define MAXALIGN(LEN)
Definition: c.h:765

References FPM_PAGE_SIZE, MAXALIGN, and size.

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 576 of file dsa.c.

577 {
579 }
void dsa_release_in_place(void *place)
Definition: dsa.c:605
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_ext(), and dsa_create_in_place_ext().

◆ dsa_on_shmem_exit_release_in_place()

void dsa_on_shmem_exit_release_in_place ( int  code,
Datum  place 
)

Definition at line 590 of file dsa.c.

591 {
593 }

References DatumGetPointer(), and dsa_release_in_place().

◆ dsa_pin()

void dsa_pin ( dsa_area area)

Definition at line 975 of file dsa.c.

976 {
978  if (area->control->pinned)
979  {
981  elog(ERROR, "dsa_area already pinned");
982  }
983  area->control->pinned = true;
984  ++area->control->refcnt;
986 }

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

Referenced by init_dsm_registry(), logicalrep_launcher_attach_dshmem(), and StatsShmemInit().

◆ dsa_pin_mapping()

void dsa_pin_mapping ( dsa_area area)

Definition at line 635 of file dsa.c.

636 {
637  int i;
638 
639  if (area->resowner != NULL)
640  {
641  area->resowner = NULL;
642 
643  for (i = 0; i <= area->high_segment_index; ++i)
644  if (area->segment_maps[i].segment != NULL)
646  }
647 }
void dsm_pin_mapping(dsm_segment *seg)
Definition: dsm.c:915
ResourceOwner resowner
Definition: dsa.c:358

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

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

◆ dsa_release_in_place()

void dsa_release_in_place ( void *  place)

Definition at line 605 of file dsa.c.

606 {
607  dsa_area_control *control = (dsa_area_control *) place;
608  int i;
609 
610  LWLockAcquire(&control->lock, LW_EXCLUSIVE);
611  Assert(control->segment_header.magic ==
612  (DSA_SEGMENT_HEADER_MAGIC ^ control->handle ^ 0));
613  Assert(control->refcnt > 0);
614  if (--control->refcnt == 0)
615  {
616  for (i = 0; i <= control->high_segment_index; ++i)
617  {
618  dsm_handle handle;
619 
620  handle = control->segment_handles[i];
621  if (handle != DSM_HANDLE_INVALID)
622  dsm_unpin_segment(handle);
623  }
624  }
625  LWLockRelease(&control->lock);
626 }
#define DSA_SEGMENT_HEADER_MAGIC
Definition: dsa.c:89
void dsm_unpin_segment(dsm_handle handle)
Definition: dsm.c:988
uint32 dsm_handle
Definition: dsm_impl.h:55
dsa_segment_header segment_header
Definition: dsa.c:290
dsa_segment_index high_segment_index
Definition: dsa.c:308
LWLock lock
Definition: dsa.c:318
dsm_handle segment_handles[DSA_MAX_SEGMENTS]
Definition: dsa.c:294
uint32 magic
Definition: dsa.c:143

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(), dsa_on_shmem_exit_release_in_place(), and pgstat_detach_shmem().

◆ 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 1043 of file dsa.c.

1044 {
1045  int size_class;
1046 
1047  /*
1048  * Trim in reverse pool order so we get to the spans-of-spans last, just
1049  * in case any become entirely free while processing all the other pools.
1050  */
1051  for (size_class = DSA_NUM_SIZE_CLASSES - 1; size_class >= 0; --size_class)
1052  {
1053  dsa_area_pool *pool = &area->control->pools[size_class];
1054  dsa_pointer span_pointer;
1055 
1056  if (size_class == DSA_SCLASS_SPAN_LARGE)
1057  {
1058  /* Large object frees give back segments aggressively already. */
1059  continue;
1060  }
1061 
1062  /*
1063  * Search fullness class 1 only. That is where we expect to find an
1064  * entirely empty superblock (entirely empty superblocks in other
1065  * fullness classes are returned to the free page map by dsa_free).
1066  */
1067  LWLockAcquire(DSA_SCLASS_LOCK(area, size_class), LW_EXCLUSIVE);
1068  span_pointer = pool->spans[1];
1069  while (DsaPointerIsValid(span_pointer))
1070  {
1071  dsa_area_span *span = dsa_get_address(area, span_pointer);
1072  dsa_pointer next = span->nextspan;
1073 
1074  if (span->nallocatable == span->nmax)
1075  destroy_superblock(area, span_pointer);
1076 
1077  span_pointer = next;
1078  }
1079  LWLockRelease(DSA_SCLASS_LOCK(area, size_class));
1080  }
1081 }
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 994 of file dsa.c.

995 {
997  Assert(area->control->refcnt > 1);
998  if (!area->control->pinned)
999  {
1001  elog(ERROR, "dsa_area not pinned");
1002  }
1003  area->control->pinned = false;
1004  --area->control->refcnt;
1006 }

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