diff options
Diffstat (limited to 'src/pkg/runtime/mcentral.c')
| -rw-r--r-- | src/pkg/runtime/mcentral.c | 14 |
1 files changed, 10 insertions, 4 deletions
diff --git a/src/pkg/runtime/mcentral.c b/src/pkg/runtime/mcentral.c index 9881812e3..7e33e01af 100644 --- a/src/pkg/runtime/mcentral.c +++ b/src/pkg/runtime/mcentral.c @@ -115,6 +115,7 @@ MCentral_Free(MCentral *c, void *v) MSpan *s; PageID page; MLink *p, *next; + int32 size; // Find span for v. page = (uintptr)v >> PageShift; @@ -136,15 +137,20 @@ MCentral_Free(MCentral *c, void *v) // If s is completely freed, return it to the heap. if(--s->ref == 0) { + size = class_to_size[c->sizeclass]; MSpanList_Remove(s); - // Freed blocks are zeroed except for the link pointer. - // Zero the link pointers so that the page is all zero. + // The second word of each freed block indicates + // whether it needs to be zeroed. The first word + // is the link pointer and must always be cleared. for(p=s->freelist; p; p=next) { next = p->next; - p->next = nil; + if(size > sizeof(uintptr) && ((uintptr*)p)[1] != 0) + runtime_memclr((byte*)p, size); + else + p->next = nil; } s->freelist = nil; - c->nfree -= (s->npages << PageShift) / class_to_size[c->sizeclass]; + c->nfree -= (s->npages << PageShift) / size; unlock(c); MHeap_Free(&mheap, s); lock(c); |