runtime·MHeap_Alloc(MHeap *h, uintptr npage, int32 sizeclass, int32 acct)
{
MSpan *s;
runtime·lock(h);
runtime·purgecachedstats(m);
s = MHeap_AllocLocked(h, npage, sizeclass);
if(s != nil) {
mstats.heap_inuse += npage<<PageShift;
if(acct) {
mstats.heap_objects++;
mstats.heap_alloc += npage<<PageShift;
}
}
runtime·unlock(h);
return s;
}
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;
}
