void
runtime·mallocinit ( void )
{
byte *p;
uintptr arena_size , bitmap_size;
extern byte end[];
byte *want;
uintptr limit;
#line 2311 "C:\Go\src\pkg\runtime\malloc.goc"
p = nil;
arena_size = 0;
bitmap_size = 0;
#line 2316 "C:\Go\src\pkg\runtime\malloc.goc"
USED ( p ) ;
USED ( arena_size ) ;
USED ( bitmap_size ) ;
#line 2320 "C:\Go\src\pkg\runtime\malloc.goc"
runtime·InitSizes ( ) ;
#line 2322 "C:\Go\src\pkg\runtime\malloc.goc"
limit = runtime·memlimit ( ) ;
#line 2327 "C:\Go\src\pkg\runtime\malloc.goc"
if ( sizeof ( void* ) == 8 && ( limit == 0 || limit > ( 1<<30 ) ) ) {
#line 2352 "C:\Go\src\pkg\runtime\malloc.goc"
arena_size = 16LL<<30;
bitmap_size = arena_size / ( sizeof ( void* ) *8/4 ) ;
p = runtime·SysReserve ( ( void* ) ( 0x00f8ULL<<32 ) , bitmap_size + arena_size ) ;
}
if ( p == nil ) {
#line 2374 "C:\Go\src\pkg\runtime\malloc.goc"
bitmap_size = MaxArena32 / ( sizeof ( void* ) *8/4 ) ;
arena_size = 512<<20;
if ( limit > 0 && arena_size+bitmap_size > limit ) {
bitmap_size = ( limit / 9 ) & ~ ( ( 1<<PageShift ) - 1 ) ;
arena_size = bitmap_size * 8;
}
#line 2390 "C:\Go\src\pkg\runtime\malloc.goc"
want = ( byte* ) ( ( ( uintptr ) end + ( 1<<18 ) + ( 1<<20 ) - 1 ) &~ ( ( 1<<20 ) -1 ) ) ;
p = runtime·SysReserve ( want , bitmap_size + arena_size ) ;
if ( p == nil )
runtime·throw ( "runtime: cannot reserve arena virtual address space" ) ;
if ( ( uintptr ) p & ( ( ( uintptr ) 1<<PageShift ) -1 ) )
runtime·printf ( "runtime: SysReserve returned unaligned address %p; asked for %p" , p , bitmap_size+arena_size ) ;
}
if ( ( uintptr ) p & ( ( ( uintptr ) 1<<PageShift ) -1 ) )
runtime·throw ( "runtime: SysReserve returned unaligned address" ) ;
#line 2400 "C:\Go\src\pkg\runtime\malloc.goc"
runtime·mheap.bitmap = p;
runtime·mheap.arena_start = p + bitmap_size;
runtime·mheap.arena_used = runtime·mheap.arena_start;
runtime·mheap.arena_end = runtime·mheap.arena_start + arena_size;
#line 2406 "C:\Go\src\pkg\runtime\malloc.goc"
runtime·MHeap_Init ( &runtime·mheap , runtime·SysAlloc ) ;
m->mcache = runtime·allocmcache ( ) ;
#line 2410 "C:\Go\src\pkg\runtime\malloc.goc"
runtime·free ( runtime·malloc ( 1 ) ) ;
}
void
runtime·mallocinit ( void )
{
byte *p;
uintptr arena_size , bitmap_size;
extern byte end[];
byte *want;
#line 264 "malloc.goc"
runtime·InitSizes ( ) ;
#line 269 "malloc.goc"
if ( sizeof ( void* ) == 8 ) {
#line 292 "malloc.goc"
arena_size = 16LL<<30;
bitmap_size = arena_size / ( sizeof ( void* ) *8/4 ) ;
p = runtime·SysReserve ( ( void* ) ( 0x00f8ULL<<32 ) , bitmap_size + arena_size ) ;
if ( p == nil )
runtime·throw ( "runtime: cannot reserve arena virtual address space" ) ;
} else {
#line 315 "malloc.goc"
bitmap_size = MaxArena32 / ( sizeof ( void* ) *8/4 ) ;
arena_size = 512<<20;
#line 327 "malloc.goc"
want = ( byte* ) ( ( ( uintptr ) end + ( 1<<18 ) + ( 1<<20 ) - 1 ) &~ ( ( 1<<20 ) -1 ) ) ;
p = runtime·SysReserve ( want , bitmap_size + arena_size ) ;
if ( p == nil )
runtime·throw ( "runtime: cannot reserve arena virtual address space" ) ;
}
if ( ( uintptr ) p & ( ( ( uintptr ) 1<<PageShift ) -1 ) )
runtime·throw ( "runtime: SysReserve returned unaligned address" ) ;
#line 335 "malloc.goc"
runtime·mheap.bitmap = p;
runtime·mheap.arena_start = p + bitmap_size;
runtime·mheap.arena_used = runtime·mheap.arena_start;
runtime·mheap.arena_end = runtime·mheap.arena_start + arena_size;
#line 341 "malloc.goc"
runtime·MHeap_Init ( &runtime·mheap , runtime·SysAlloc ) ;
m->mcache = runtime·allocmcache ( ) ;
#line 345 "malloc.goc"
runtime·free ( runtime·malloc ( 1 ) ) ;
}
runtime·MHeap_SysAlloc ( MHeap *h , uintptr n )
{
byte *p;
#line 2418 "C:\Go\src\pkg\runtime\malloc.goc"
if ( n > h->arena_end - h->arena_used ) {
#line 2421 "C:\Go\src\pkg\runtime\malloc.goc"
byte *new_end;
uintptr needed;
#line 2424 "C:\Go\src\pkg\runtime\malloc.goc"
needed = ( uintptr ) h->arena_used + n - ( uintptr ) h->arena_end;
#line 2426 "C:\Go\src\pkg\runtime\malloc.goc"
needed = ( needed + ( 256<<20 ) - 1 ) & ~ ( ( 256<<20 ) -1 ) ;
new_end = h->arena_end + needed;
if ( new_end <= h->arena_start + MaxArena32 ) {
p = runtime·SysReserve ( h->arena_end , new_end - h->arena_end ) ;
if ( p == h->arena_end )
h->arena_end = new_end;
}
}
if ( n <= h->arena_end - h->arena_used ) {
#line 2436 "C:\Go\src\pkg\runtime\malloc.goc"
p = h->arena_used;
runtime·SysMap ( p , n ) ;
h->arena_used += n;
runtime·MHeap_MapBits ( h ) ;
return p;
}
#line 2444 "C:\Go\src\pkg\runtime\malloc.goc"
if ( sizeof ( void* ) == 8 && ( uintptr ) h->bitmap >= 0xffffffffU )
return nil;
#line 2450 "C:\Go\src\pkg\runtime\malloc.goc"
p = runtime·SysAlloc ( n ) ;
if ( p == nil )
return nil;
#line 2454 "C:\Go\src\pkg\runtime\malloc.goc"
if ( p < h->arena_start || p+n - h->arena_start >= MaxArena32 ) {
runtime·printf ( "runtime: memory allocated by OS (%p) not in usable range [%p,%p)\n" ,
p , h->arena_start , h->arena_start+MaxArena32 ) ;
runtime·SysFree ( p , n ) ;
return nil;
}
#line 2461 "C:\Go\src\pkg\runtime\malloc.goc"
if ( p+n > h->arena_used ) {
h->arena_used = p+n;
if ( h->arena_used > h->arena_end )
h->arena_end = h->arena_used;
runtime·MHeap_MapBits ( h ) ;
}
#line 2468 "C:\Go\src\pkg\runtime\malloc.goc"
return p;
}
runtime·MHeap_SysAlloc(MHeap *h, uintptr n)
{
byte *p, *p_end;
uintptr p_size;
bool reserved;
if(n > h->arena_end - h->arena_used) {
// We are in 32-bit mode, maybe we didn't use all possible address space yet.
// Reserve some more space.
byte *new_end;
p_size = ROUND(n + PageSize, 256<<20);
new_end = h->arena_end + p_size;
if(new_end <= h->arena_start + MaxArena32) {
// TODO: It would be bad if part of the arena
// is reserved and part is not.
p = runtime·SysReserve(h->arena_end, p_size, &reserved);
if(p == h->arena_end) {
h->arena_end = new_end;
h->arena_reserved = reserved;
}
else if(p+p_size <= h->arena_start + MaxArena32) {
// Keep everything page-aligned.
// Our pages are bigger than hardware pages.
h->arena_end = p+p_size;
h->arena_used = p + (-(uintptr)p&(PageSize-1));
h->arena_reserved = reserved;
} else {
uint64 stat;
stat = 0;
runtime·SysFree(p, p_size, &stat);
}
}
}
if(n <= h->arena_end - h->arena_used) {
// Keep taking from our reservation.
p = h->arena_used;
runtime·SysMap(p, n, h->arena_reserved, &mstats.heap_sys);
h->arena_used += n;
runtime·MHeap_MapBits(h);
runtime·MHeap_MapSpans(h);
if(raceenabled)
runtime·racemapshadow(p, n);
if(((uintptr)p & (PageSize-1)) != 0)
runtime·throw("misrounded allocation in MHeap_SysAlloc");
return p;
}
// If using 64-bit, our reservation is all we have.
if(h->arena_end - h->arena_start >= MaxArena32)
return nil;
// On 32-bit, once the reservation is gone we can
// try to get memory at a location chosen by the OS
// and hope that it is in the range we allocated bitmap for.
p_size = ROUND(n, PageSize) + PageSize;
p = runtime·sysAlloc(p_size, &mstats.heap_sys);
if(p == nil)
return nil;
if(p < h->arena_start || p+p_size - h->arena_start >= MaxArena32) {
runtime·printf("runtime: memory allocated by OS (%p) not in usable range [%p,%p)\n",
p, h->arena_start, h->arena_start+MaxArena32);
runtime·SysFree(p, p_size, &mstats.heap_sys);
return nil;
}
p_end = p + p_size;
p += -(uintptr)p & (PageSize-1);
if(p+n > h->arena_used) {
h->arena_used = p+n;
if(p_end > h->arena_end)
h->arena_end = p_end;
runtime·MHeap_MapBits(h);
runtime·MHeap_MapSpans(h);
if(raceenabled)
runtime·racemapshadow(p, n);
}
if(((uintptr)p & (PageSize-1)) != 0)
runtime·throw("misrounded allocation in MHeap_SysAlloc");
return p;
}
void
runtime·mallocinit(void)
{
byte *p, *p1;
uintptr arena_size, bitmap_size, spans_size, p_size;
extern byte runtime·end[];
uintptr limit;
uint64 i;
bool reserved;
p = nil;
p_size = 0;
arena_size = 0;
bitmap_size = 0;
spans_size = 0;
reserved = false;
// for 64-bit build
USED(p);
USED(p_size);
USED(arena_size);
USED(bitmap_size);
USED(spans_size);
runtime·InitSizes();
if(runtime·class_to_size[TinySizeClass] != TinySize)
runtime·throw("bad TinySizeClass");
// limit = runtime·memlimit();
// See https://code.google.com/p/go/issues/detail?id=5049
// TODO(rsc): Fix after 1.1.
limit = 0;
// Set up the allocation arena, a contiguous area of memory where
// allocated data will be found. The arena begins with a bitmap large
// enough to hold 4 bits per allocated word.
if(sizeof(void*) == 8 && (limit == 0 || limit > (1<<30))) {
// On a 64-bit machine, allocate from a single contiguous reservation.
// 128 GB (MaxMem) should be big enough for now.
//
// The code will work with the reservation at any address, but ask
// SysReserve to use 0x0000XXc000000000 if possible (XX=00...7f).
// Allocating a 128 GB region takes away 37 bits, and the amd64
// doesn't let us choose the top 17 bits, so that leaves the 11 bits
// in the middle of 0x00c0 for us to choose. Choosing 0x00c0 means
// that the valid memory addresses will begin 0x00c0, 0x00c1, ..., 0x00df.
// In little-endian, that's c0 00, c1 00, ..., df 00. None of those are valid
// UTF-8 sequences, and they are otherwise as far away from
// ff (likely a common byte) as possible. If that fails, we try other 0xXXc0
// addresses. An earlier attempt to use 0x11f8 caused out of memory errors
// on OS X during thread allocations. 0x00c0 causes conflicts with
// AddressSanitizer which reserves all memory up to 0x0100.
// These choices are both for debuggability and to reduce the
// odds of the conservative garbage collector not collecting memory
// because some non-pointer block of memory had a bit pattern
// that matched a memory address.
//
// Actually we reserve 136 GB (because the bitmap ends up being 8 GB)
// but it hardly matters: e0 00 is not valid UTF-8 either.
//
// If this fails we fall back to the 32 bit memory mechanism
arena_size = MaxMem;
bitmap_size = arena_size / (sizeof(void*)*8/4);
spans_size = arena_size / PageSize * sizeof(runtime·mheap.spans[0]);
spans_size = ROUND(spans_size, PageSize);
for(i = 0; i <= 0x7f; i++) {
p = (void*)(i<<40 | 0x00c0ULL<<32);
p_size = bitmap_size + spans_size + arena_size + PageSize;
p = runtime·SysReserve(p, p_size, &reserved);
if(p != nil)
break;
}
}
if (p == nil) {
// On a 32-bit machine, we can't typically get away
// with a giant virtual address space reservation.
// Instead we map the memory information bitmap
// immediately after the data segment, large enough
// to handle another 2GB of mappings (256 MB),
// along with a reservation for another 512 MB of memory.
// When that gets used up, we'll start asking the kernel
// for any memory anywhere and hope it's in the 2GB
// following the bitmap (presumably the executable begins
// near the bottom of memory, so we'll have to use up
// most of memory before the kernel resorts to giving out
// memory before the beginning of the text segment).
//
// Alternatively we could reserve 512 MB bitmap, enough
// for 4GB of mappings, and then accept any memory the
// kernel threw at us, but normally that's a waste of 512 MB
// of address space, which is probably too much in a 32-bit world.
bitmap_size = MaxArena32 / (sizeof(void*)*8/4);
arena_size = 512<<20;
spans_size = MaxArena32 / PageSize * sizeof(runtime·mheap.spans[0]);
if(limit > 0 && arena_size+bitmap_size+spans_size > limit) {
bitmap_size = (limit / 9) & ~((1<<PageShift) - 1);
arena_size = bitmap_size * 8;
spans_size = arena_size / PageSize * sizeof(runtime·mheap.spans[0]);
}
spans_size = ROUND(spans_size, PageSize);
// SysReserve treats the address we ask for, end, as a hint,
// not as an absolute requirement. If we ask for the end
// of the data segment but the operating system requires
// a little more space before we can start allocating, it will
// give out a slightly higher pointer. Except QEMU, which
// is buggy, as usual: it won't adjust the pointer upward.
// So adjust it upward a little bit ourselves: 1/4 MB to get
// away from the running binary image and then round up
// to a MB boundary.
p = (byte*)ROUND((uintptr)runtime·end + (1<<18), 1<<20);
p_size = bitmap_size + spans_size + arena_size + PageSize;
p = runtime·SysReserve(p, p_size, &reserved);
if(p == nil)
runtime·throw("runtime: cannot reserve arena virtual address space");
}
// PageSize can be larger than OS definition of page size,
// so SysReserve can give us a PageSize-unaligned pointer.
// To overcome this we ask for PageSize more and round up the pointer.
p1 = (byte*)ROUND((uintptr)p, PageSize);
runtime·mheap.spans = (MSpan**)p1;
runtime·mheap.bitmap = p1 + spans_size;
runtime·mheap.arena_start = p1 + spans_size + bitmap_size;
runtime·mheap.arena_used = runtime·mheap.arena_start;
runtime·mheap.arena_end = p + p_size;
runtime·mheap.arena_reserved = reserved;
if(((uintptr)runtime·mheap.arena_start & (PageSize-1)) != 0)
runtime·throw("misrounded allocation in mallocinit");
// Initialize the rest of the allocator.
runtime·MHeap_Init(&runtime·mheap);
g->m->mcache = runtime·allocmcache();
}
