From 79a1d94225dae859a5eb0c39062e6cb924664413 Mon Sep 17 00:00:00 2001 From: "dgrowley@gmail.com" Date: Tue, 7 Apr 2020 17:56:54 +1200 Subject: [PATCH v7 2/3] Modify various power 2 calculations to use new helper functions First pass of modifying various places which obtain the next power of 2 of a number and make them use the new functions added in pg_bitutils instead. --- src/backend/access/hash/hashpage.c | 24 +++++++++++------------- src/backend/access/hash/hashsort.c | 3 ++- src/backend/access/hash/hashutil.c | 4 ++-- src/backend/utils/hash/dynahash.c | 14 +++++++------- src/include/lib/simplehash.h | 27 ++++----------------------- src/tools/msvc/Mkvcbuild.pm | 2 +- 6 files changed, 27 insertions(+), 47 deletions(-) diff --git a/src/backend/access/hash/hashpage.c b/src/backend/access/hash/hashpage.c index 55d85644a4..a664ecf494 100644 --- a/src/backend/access/hash/hashpage.c +++ b/src/backend/access/hash/hashpage.c @@ -31,6 +31,7 @@ #include "access/hash.h" #include "access/hash_xlog.h" #include "miscadmin.h" +#include "port/pg_bitutils.h" #include "storage/lmgr.h" #include "storage/predicate.h" #include "storage/smgr.h" @@ -502,7 +503,7 @@ _hash_init_metabuffer(Buffer buf, double num_tuples, RegProcedure procid, double dnumbuckets; uint32 num_buckets; uint32 spare_index; - uint32 i; + uint32 lshift; /* * Choose the number of initial bucket pages to match the fill factor @@ -542,15 +543,12 @@ _hash_init_metabuffer(Buffer buf, double num_tuples, RegProcedure procid, metap->hashm_nmaps = 0; metap->hashm_ffactor = ffactor; metap->hashm_bsize = HashGetMaxBitmapSize(page); + /* find largest bitmap array size that will fit in page size */ - for (i = _hash_log2(metap->hashm_bsize); i > 0; --i) - { - if ((1 << i) <= metap->hashm_bsize) - break; - } - Assert(i > 0); - metap->hashm_bmsize = 1 << i; - metap->hashm_bmshift = i + BYTE_TO_BIT; + lshift = pg_leftmost_one_pos32(metap->hashm_bsize); + Assert(lshift > 0); + metap->hashm_bmsize = 1 << lshift; + metap->hashm_bmshift = lshift + BYTE_TO_BIT; Assert((1 << BMPG_SHIFT(metap)) == (BMPG_MASK(metap) + 1)); /* @@ -570,7 +568,7 @@ _hash_init_metabuffer(Buffer buf, double num_tuples, RegProcedure procid, * Set highmask as next immediate ((2 ^ x) - 1), which should be * sufficient to cover num_buckets. */ - metap->hashm_highmask = (1 << (_hash_log2(num_buckets + 1))) - 1; + metap->hashm_highmask = pg_nextpower2_32(num_buckets + 1) - 1; metap->hashm_lowmask = (metap->hashm_highmask >> 1); MemSet(metap->hashm_spares, 0, sizeof(metap->hashm_spares)); @@ -659,9 +657,9 @@ restart_expand: * * Ideally we'd allow bucket numbers up to UINT_MAX-1 (no higher because * the calculation maxbucket+1 mustn't overflow). Currently we restrict - * to half that because of overflow looping in _hash_log2() and - * insufficient space in hashm_spares[]. It's moot anyway because an - * index with 2^32 buckets would certainly overflow BlockNumber and hence + * to half that to prevent failure of pg_ceil_log2_32() and insufficient + * space in hashm_spares[]. It's moot anyway because an index with 2^32 + * buckets would certainly overflow BlockNumber and hence * _hash_alloc_buckets() would fail, but if we supported buckets smaller * than a disk block then this would be an independent constraint. * diff --git a/src/backend/access/hash/hashsort.c b/src/backend/access/hash/hashsort.c index 9cb41d62e7..2c7b5857b5 100644 --- a/src/backend/access/hash/hashsort.c +++ b/src/backend/access/hash/hashsort.c @@ -29,6 +29,7 @@ #include "commands/progress.h" #include "miscadmin.h" #include "pgstat.h" +#include "port/pg_bitutils.h" #include "utils/tuplesort.h" @@ -69,7 +70,7 @@ _h_spoolinit(Relation heap, Relation index, uint32 num_buckets) * NOTE : This hash mask calculation should be in sync with similar * calculation in _hash_init_metabuffer. */ - hspool->high_mask = (((uint32) 1) << _hash_log2(num_buckets + 1)) - 1; + hspool->high_mask = pg_nextpower2_32(num_buckets + 1) - 1; hspool->low_mask = (hspool->high_mask >> 1); hspool->max_buckets = num_buckets - 1; diff --git a/src/backend/access/hash/hashutil.c b/src/backend/access/hash/hashutil.c index 9efc8016bc..9770d17ff4 100644 --- a/src/backend/access/hash/hashutil.c +++ b/src/backend/access/hash/hashutil.c @@ -17,6 +17,7 @@ #include "access/hash.h" #include "access/reloptions.h" #include "access/relscan.h" +#include "port/pg_bitutils.h" #include "storage/buf_internals.h" #include "utils/lsyscache.h" #include "utils/rel.h" @@ -158,8 +159,7 @@ _hash_spareindex(uint32 num_bucket) { uint32 splitpoint_group; uint32 splitpoint_phases; - - splitpoint_group = _hash_log2(num_bucket); + splitpoint_group = pg_ceil_log2_32(num_bucket); if (splitpoint_group < HASH_SPLITPOINT_GROUPS_WITH_ONE_PHASE) return splitpoint_group; diff --git a/src/backend/utils/hash/dynahash.c b/src/backend/utils/hash/dynahash.c index b5381958e7..5b4b9e487f 100644 --- a/src/backend/utils/hash/dynahash.c +++ b/src/backend/utils/hash/dynahash.c @@ -87,6 +87,7 @@ #include "access/xact.h" #include "common/hashfn.h" +#include "port/pg_bitutils.h" #include "storage/shmem.h" #include "storage/spin.h" #include "utils/dynahash.h" @@ -1718,16 +1719,15 @@ hash_corrupted(HTAB *hashp) int my_log2(long num) { - int i; - long limit; - - /* guard against too-large input, which would put us into infinite loop */ + /* guard against too-large input, which would be invalid for pg_ceil_log2_*() */ if (num > LONG_MAX / 2) num = LONG_MAX / 2; - for (i = 0, limit = 1; limit < num; i++, limit <<= 1) - ; - return i; +#if SIZEOF_LONG < 8 + return pg_ceil_log2_32(num); +#else + return pg_ceil_log2_64(num); +#endif } /* calculate first power of 2 >= num, bounded to what will fit in a long */ diff --git a/src/include/lib/simplehash.h b/src/include/lib/simplehash.h index 5a6783f653..8cb03cda6c 100644 --- a/src/include/lib/simplehash.h +++ b/src/include/lib/simplehash.h @@ -57,6 +57,8 @@ * backwards, unless they're empty or already at their optimal position. */ +#include "port/pg_bitutils.h" + /* helpers */ #define SH_MAKE_PREFIX(a) CppConcat(a,_) #define SH_MAKE_NAME(name) SH_MAKE_NAME_(SH_MAKE_PREFIX(SH_PREFIX),name) @@ -215,27 +217,6 @@ SH_SCOPE void SH_STAT(SH_TYPE * tb); #ifndef SIMPLEHASH_H #define SIMPLEHASH_H -/* FIXME: can we move these to a central location? */ - -/* calculate ceil(log base 2) of num */ -static inline uint64 -sh_log2(uint64 num) -{ - int i; - uint64 limit; - - for (i = 0, limit = 1; limit < num; i++, limit <<= 1) - ; - return i; -} - -/* calculate first power of 2 >= num */ -static inline uint64 -sh_pow2(uint64 num) -{ - return ((uint64) 1) << sh_log2(num); -} - #ifdef FRONTEND #define sh_error(...) pg_log_error(__VA_ARGS__) #define sh_log(...) pg_log_info(__VA_ARGS__) @@ -259,7 +240,7 @@ SH_COMPUTE_PARAMETERS(SH_TYPE * tb, uint32 newsize) size = Max(newsize, 2); /* round up size to the next power of 2, that's how bucketing works */ - size = sh_pow2(size); + size = pg_nextpower2_64(size); Assert(size <= SH_MAX_SIZE); /* @@ -434,7 +415,7 @@ SH_GROW(SH_TYPE * tb, uint32 newsize) uint32 startelem = 0; uint32 copyelem; - Assert(oldsize == sh_pow2(oldsize)); + Assert(oldsize == pg_nextpower2_64(oldsize)); Assert(oldsize != SH_MAX_SIZE); Assert(oldsize < newsize); diff --git a/src/tools/msvc/Mkvcbuild.pm b/src/tools/msvc/Mkvcbuild.pm index 72a21dbd41..fd7d4021a5 100644 --- a/src/tools/msvc/Mkvcbuild.pm +++ b/src/tools/msvc/Mkvcbuild.pm @@ -81,7 +81,7 @@ my $frontend_extrasource = { }; my @frontend_excludes = ( 'pgevent', 'pg_basebackup', 'pg_rewind', 'pg_dump', - 'pg_waldump', 'scripts'); + 'pg_validatebackup', 'pg_waldump', 'scripts'); sub mkvcbuild { -- 2.25.1