diff options
Diffstat (limited to 'src/runtime/mbitmap.go')
| -rw-r--r-- | src/runtime/mbitmap.go | 22 |
1 files changed, 22 insertions, 0 deletions
diff --git a/src/runtime/mbitmap.go b/src/runtime/mbitmap.go index 508de9a115..37a92c64bc 100644 --- a/src/runtime/mbitmap.go +++ b/src/runtime/mbitmap.go @@ -1267,6 +1267,28 @@ func markBitsForSpan(base uintptr) (mbits markBits) { return mbits } +// isMarkedOrNotInHeap returns true if a pointer is in the heap and marked, +// or if the pointer is not in the heap. Used by goroutine leak detection +// to determine if concurrency resources are reachable in memory. +func isMarkedOrNotInHeap(p unsafe.Pointer) bool { + obj, span, objIndex := findObject(uintptr(p), 0, 0) + if obj != 0 { + mbits := span.markBitsForIndex(objIndex) + return mbits.isMarked() + } + + // If we fall through to get here, the object is not in the heap. + // In this case, it is either a pointer to a stack object or a global resource. + // Treat it as reachable in memory by default, to be safe. + // + // TODO(vsaioc): we could be more precise by checking against the stacks + // of runnable goroutines. I don't think this is necessary, based on what we've seen, but + // let's keep the option open in case the runtime evolves. + // This will (naively) lead to quadratic blow-up for goroutine leak detection, + // but if it is only run on demand, maybe the extra cost is not a show-stopper. + return true +} + // advance advances the markBits to the next object in the span. func (m *markBits) advance() { if m.mask == 1<<7 { |