diff options
Diffstat (limited to 'src/runtime')
| -rw-r--r-- | src/runtime/mbitmap.go | 5 | ||||
| -rw-r--r-- | src/runtime/mheap.go | 13 |
2 files changed, 14 insertions, 4 deletions
diff --git a/src/runtime/mbitmap.go b/src/runtime/mbitmap.go index 369b5ed218..702fccae98 100644 --- a/src/runtime/mbitmap.go +++ b/src/runtime/mbitmap.go @@ -176,7 +176,10 @@ func heapBitsForObject(p uintptr) (base uintptr, hbits heapBits) { x -= mheap_.arena_start >> _PageShift s := h_spans[x] if s == nil || pageID(k) < s.start || p >= s.limit || s.state != mSpanInUse { - if s != nil && s.state == _MSpanStack { + if s == nil || s.state == _MSpanStack { + // If s is nil, the virtual address has never been part of the heap. + // This pointer may be to some mmap'd region, so we allow it. + // Pointers into stacks are also ok, the runtime manages these explicitly. return } diff --git a/src/runtime/mheap.go b/src/runtime/mheap.go index ba800aacef..a05a570ff1 100644 --- a/src/runtime/mheap.go +++ b/src/runtime/mheap.go @@ -128,7 +128,13 @@ func (s *mspan) layout() (size, n, total uintptr) { } var h_allspans []*mspan // TODO: make this h.allspans once mheap can be defined in Go -var h_spans []*mspan // TODO: make this h.spans once mheap can be defined in Go + +// h_spans is a lookup table to map virtual address page IDs to *mspan. +// For allocated spans, their pages map to the span itself. +// For free spans, only the lowest and highest pages map to the span itself. Internal +// pages map to an arbitrary span. +// For pages that have never been allocated, h_spans entries are nil. +var h_spans []*mspan // TODO: make this h.spans once mheap can be defined in Go func recordspan(vh unsafe.Pointer, p unsafe.Pointer) { h := (*mheap)(vh) @@ -568,8 +574,9 @@ func mHeap_Grow(h *mheap, npage uintptr) bool { mSpan_Init(s, pageID(uintptr(v)>>_PageShift), ask>>_PageShift) p := uintptr(s.start) p -= (uintptr(unsafe.Pointer(h.arena_start)) >> _PageShift) - h_spans[p] = s - h_spans[p+s.npages-1] = s + for i := p; i < p+s.npages; i++ { + h_spans[i] = s + } atomicstore(&s.sweepgen, h.sweepgen) s.state = _MSpanInUse mHeap_FreeSpanLocked(h, s, false, true, 0) |