diff options
Diffstat (limited to 'src/mem1.c')
-rw-r--r-- | src/mem1.c | 137 |
1 files changed, 133 insertions, 4 deletions
@@ -15,7 +15,31 @@ ** to obtain the memory it needs. ** ** This file contains implementations of the low-level memory allocation -** routines specified in the sqlite3_mem_methods object. +** routines specified in the sqlite3_mem_methods object. The content of +** this file is only used if SQLITE_SYSTEM_MALLOC is defined. The +** SQLITE_SYSTEM_MALLOC macro is defined automatically if neither the +** SQLITE_MEMDEBUG nor the SQLITE_WIN32_MALLOC macros are defined. The +** default configuration is to use memory allocation routines in this +** file. +** +** C-preprocessor macro summary: +** +** HAVE_MALLOC_USABLE_SIZE The configure script sets this symbol if +** the malloc_usable_size() interface exists +** on the target platform. Or, this symbol +** can be set manually, if desired. +** If an equivalent interface exists by +** a different name, using a separate -D +** option to rename it. +** +** SQLITE_WITHOUT_ZONEMALLOC Some older macs lack support for the zone +** memory allocator. Set this symbol to enable +** building on older macs. +** +** SQLITE_WITHOUT_MSIZE Set this symbol to disable the use of +** _msize() on windows systems. This might +** be necessary when compiling for Delphi, +** for example. */ #include "sqliteInt.h" @@ -27,6 +51,55 @@ #ifdef SQLITE_SYSTEM_MALLOC /* +** The MSVCRT has malloc_usable_size() but it is called _msize(). +** The use of _msize() is automatic, but can be disabled by compiling +** with -DSQLITE_WITHOUT_MSIZE +*/ +#if defined(_MSC_VER) && !defined(SQLITE_WITHOUT_MSIZE) +# define SQLITE_MALLOCSIZE _msize +#endif + +#if defined(__APPLE__) && !defined(SQLITE_WITHOUT_ZONEMALLOC) + +/* +** Use the zone allocator available on apple products unless the +** SQLITE_WITHOUT_ZONEMALLOC symbol is defined. +*/ +#include <sys/sysctl.h> +#include <malloc/malloc.h> +#include <libkern/OSAtomic.h> +static malloc_zone_t* _sqliteZone_; +#define SQLITE_MALLOC(x) malloc_zone_malloc(_sqliteZone_, (x)) +#define SQLITE_FREE(x) malloc_zone_free(_sqliteZone_, (x)); +#define SQLITE_REALLOC(x,y) malloc_zone_realloc(_sqliteZone_, (x), (y)) +#define SQLITE_MALLOCSIZE(x) \ + (_sqliteZone_ ? _sqliteZone_->size(_sqliteZone_,x) : malloc_size(x)) + +#else /* if not __APPLE__ */ + +/* +** Use standard C library malloc and free on non-Apple systems. +** Also used by Apple systems if SQLITE_WITHOUT_ZONEMALLOC is defined. +*/ +#define SQLITE_MALLOC(x) malloc(x) +#define SQLITE_FREE(x) free(x) +#define SQLITE_REALLOC(x,y) realloc((x),(y)) + +#if (defined(_MSC_VER) && !defined(SQLITE_WITHOUT_MSIZE)) \ + || (defined(HAVE_MALLOC_H) && defined(HAVE_MALLOC_USABLE_SIZE)) +# include <malloc.h> /* Needed for malloc_usable_size on linux */ +#endif +#ifdef HAVE_MALLOC_USABLE_SIZE +# ifndef SQLITE_MALLOCSIZE +# define SQLITE_MALLOCSIZE(x) malloc_usable_size(x) +# endif +#else +# undef SQLITE_MALLOCSIZE +#endif + +#endif /* __APPLE__ or not __APPLE__ */ + +/* ** Like malloc(), but remember the size of the allocation ** so that we can find it later using sqlite3MemSize(). ** @@ -35,10 +108,18 @@ ** routines. */ static void *sqlite3MemMalloc(int nByte){ +#ifdef SQLITE_MALLOCSIZE + void *p = SQLITE_MALLOC( nByte ); + if( p==0 ){ + testcase( sqlite3GlobalConfig.xLog!=0 ); + sqlite3_log(SQLITE_NOMEM, "failed to allocate %u bytes of memory", nByte); + } + return p; +#else sqlite3_int64 *p; assert( nByte>0 ); nByte = ROUND8(nByte); - p = malloc( nByte+8 ); + p = SQLITE_MALLOC( nByte+8 ); if( p ){ p[0] = nByte; p++; @@ -47,6 +128,7 @@ static void *sqlite3MemMalloc(int nByte){ sqlite3_log(SQLITE_NOMEM, "failed to allocate %u bytes of memory", nByte); } return (void *)p; +#endif } /* @@ -58,10 +140,14 @@ static void *sqlite3MemMalloc(int nByte){ ** by higher-level routines. */ static void sqlite3MemFree(void *pPrior){ +#ifdef SQLITE_MALLOCSIZE + SQLITE_FREE(pPrior); +#else sqlite3_int64 *p = (sqlite3_int64*)pPrior; assert( pPrior!=0 ); p--; - free(p); + SQLITE_FREE(p); +#endif } /* @@ -69,11 +155,15 @@ static void sqlite3MemFree(void *pPrior){ ** or xRealloc(). */ static int sqlite3MemSize(void *pPrior){ +#ifdef SQLITE_MALLOCSIZE + return pPrior ? (int)SQLITE_MALLOCSIZE(pPrior) : 0; +#else sqlite3_int64 *p; if( pPrior==0 ) return 0; p = (sqlite3_int64*)pPrior; p--; return (int)p[0]; +#endif } /* @@ -87,11 +177,21 @@ static int sqlite3MemSize(void *pPrior){ ** routines and redirected to xFree. */ static void *sqlite3MemRealloc(void *pPrior, int nByte){ +#ifdef SQLITE_MALLOCSIZE + void *p = SQLITE_REALLOC(pPrior, nByte); + if( p==0 ){ + testcase( sqlite3GlobalConfig.xLog!=0 ); + sqlite3_log(SQLITE_NOMEM, + "failed memory resize %u to %u bytes", + SQLITE_MALLOCSIZE(pPrior), nByte); + } + return p; +#else sqlite3_int64 *p = (sqlite3_int64*)pPrior; assert( pPrior!=0 && nByte>0 ); assert( nByte==ROUND8(nByte) ); /* EV: R-46199-30249 */ p--; - p = realloc(p, nByte+8 ); + p = SQLITE_REALLOC(p, nByte+8 ); if( p ){ p[0] = nByte; p++; @@ -102,6 +202,7 @@ static void *sqlite3MemRealloc(void *pPrior, int nByte){ sqlite3MemSize(pPrior), nByte); } return (void*)p; +#endif } /* @@ -115,6 +216,34 @@ static int sqlite3MemRoundup(int n){ ** Initialize this module. */ static int sqlite3MemInit(void *NotUsed){ +#if defined(__APPLE__) && !defined(SQLITE_WITHOUT_ZONEMALLOC) + int cpuCount; + size_t len; + if( _sqliteZone_ ){ + return SQLITE_OK; + } + len = sizeof(cpuCount); + /* One usually wants to use hw.acctivecpu for MT decisions, but not here */ + sysctlbyname("hw.ncpu", &cpuCount, &len, NULL, 0); + if( cpuCount>1 ){ + /* defer MT decisions to system malloc */ + _sqliteZone_ = malloc_default_zone(); + }else{ + /* only 1 core, use our own zone to contention over global locks, + ** e.g. we have our own dedicated locks */ + bool success; + malloc_zone_t* newzone = malloc_create_zone(4096, 0); + malloc_set_zone_name(newzone, "Sqlite_Heap"); + do{ + success = OSAtomicCompareAndSwapPtrBarrier(NULL, newzone, + (void * volatile *)&_sqliteZone_); + }while(!_sqliteZone_); + if( !success ){ + /* somebody registered a zone first */ + malloc_destroy_zone(newzone); + } + } +#endif UNUSED_PARAMETER(NotUsed); return SQLITE_OK; } |