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Diffstat (limited to 'src/runtime/malloc.c')
| -rw-r--r-- | src/runtime/malloc.c | 396 |
1 files changed, 0 insertions, 396 deletions
diff --git a/src/runtime/malloc.c b/src/runtime/malloc.c deleted file mode 100644 index b79c30b72..000000000 --- a/src/runtime/malloc.c +++ /dev/null @@ -1,396 +0,0 @@ -// Copyright 2009 The Go Authors. All rights reserved. -// Use of this source code is governed by a BSD-style -// license that can be found in the LICENSE file. - -// See malloc.h for overview. -// -// TODO(rsc): double-check stats. - -#include "runtime.h" -#include "arch_GOARCH.h" -#include "malloc.h" -#include "type.h" -#include "typekind.h" -#include "race.h" -#include "stack.h" -#include "textflag.h" - -// Mark mheap as 'no pointers', it does not contain interesting pointers but occupies ~45K. -#pragma dataflag NOPTR -MHeap runtime·mheap; -#pragma dataflag NOPTR -MStats runtime·memstats; - -int32 -runtime·mlookup(void *v, byte **base, uintptr *size, MSpan **sp) -{ - uintptr n, i; - byte *p; - MSpan *s; - - g->m->mcache->local_nlookup++; - if (sizeof(void*) == 4 && g->m->mcache->local_nlookup >= (1<<30)) { - // purge cache stats to prevent overflow - runtime·lock(&runtime·mheap.lock); - runtime·purgecachedstats(g->m->mcache); - runtime·unlock(&runtime·mheap.lock); - } - - s = runtime·MHeap_LookupMaybe(&runtime·mheap, v); - if(sp) - *sp = s; - if(s == nil) { - if(base) - *base = nil; - if(size) - *size = 0; - return 0; - } - - p = (byte*)((uintptr)s->start<<PageShift); - if(s->sizeclass == 0) { - // Large object. - if(base) - *base = p; - if(size) - *size = s->npages<<PageShift; - return 1; - } - - n = s->elemsize; - if(base) { - i = ((byte*)v - p)/n; - *base = p + i*n; - } - if(size) - *size = n; - - return 1; -} - -#pragma textflag NOSPLIT -void -runtime·purgecachedstats(MCache *c) -{ - MHeap *h; - int32 i; - - // Protected by either heap or GC lock. - h = &runtime·mheap; - mstats.heap_alloc += c->local_cachealloc; - c->local_cachealloc = 0; - mstats.tinyallocs += c->local_tinyallocs; - c->local_tinyallocs = 0; - mstats.nlookup += c->local_nlookup; - c->local_nlookup = 0; - h->largefree += c->local_largefree; - c->local_largefree = 0; - h->nlargefree += c->local_nlargefree; - c->local_nlargefree = 0; - for(i=0; i<nelem(c->local_nsmallfree); i++) { - h->nsmallfree[i] += c->local_nsmallfree[i]; - c->local_nsmallfree[i] = 0; - } -} - -// Size of the trailing by_size array differs between Go and C, -// and all data after by_size is local to C, not exported to Go. -// NumSizeClasses was changed, but we can not change Go struct because of backward compatibility. -// sizeof_C_MStats is what C thinks about size of Go struct. -uintptr runtime·sizeof_C_MStats = offsetof(MStats, by_size[61]); - -#define MaxArena32 (2U<<30) - -// For use by Go. If it were a C enum it would be made available automatically, -// but the value of MaxMem is too large for enum. -uintptr runtime·maxmem = MaxMem; - -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(); -} - -void* -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·setFinalizer_m(void) -{ - FuncVal *fn; - void *arg; - uintptr nret; - Type *fint; - PtrType *ot; - - fn = g->m->ptrarg[0]; - arg = g->m->ptrarg[1]; - nret = g->m->scalararg[0]; - fint = g->m->ptrarg[2]; - ot = g->m->ptrarg[3]; - g->m->ptrarg[0] = nil; - g->m->ptrarg[1] = nil; - g->m->ptrarg[2] = nil; - g->m->ptrarg[3] = nil; - - g->m->scalararg[0] = runtime·addfinalizer(arg, fn, nret, fint, ot); -} - -void -runtime·removeFinalizer_m(void) -{ - void *p; - - p = g->m->ptrarg[0]; - g->m->ptrarg[0] = nil; - runtime·removefinalizer(p); -} - -// mcallable cache refill -void -runtime·mcacheRefill_m(void) -{ - runtime·MCache_Refill(g->m->mcache, (int32)g->m->scalararg[0]); -} - -void -runtime·largeAlloc_m(void) -{ - uintptr npages, size; - MSpan *s; - void *v; - int32 flag; - - //runtime·printf("largeAlloc size=%D\n", g->m->scalararg[0]); - // Allocate directly from heap. - size = g->m->scalararg[0]; - flag = (int32)g->m->scalararg[1]; - if(size + PageSize < size) - runtime·throw("out of memory"); - npages = size >> PageShift; - if((size & PageMask) != 0) - npages++; - s = runtime·MHeap_Alloc(&runtime·mheap, npages, 0, 1, !(flag & FlagNoZero)); - if(s == nil) - runtime·throw("out of memory"); - s->limit = (byte*)(s->start<<PageShift) + size; - v = (void*)(s->start << PageShift); - // setup for mark sweep - runtime·markspan(v, 0, 0, true); - g->m->ptrarg[0] = s; -} |