code review 69870055: runtime: fix runaway memory usage

src/pkg/runtime/malloc.goc

 // 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.
 
 package runtime
 #include "runtime.h"
@@ skipping 311 matching lines @@
         } else {
                 // Small object.
                 if(size > 2*sizeof(uintptr))
                         ((uintptr*)v)[1] = (uintptr)0xfeedfeedfeedfeedll;       // mark as "needs to be zeroed"
                 else if(size > sizeof(uintptr))
                         ((uintptr*)v)[1] = 0;
                 // Must mark v freed before calling MCache_Free:
                 // it might coalesce v and other blocks into a bigger span
                 // and change the bitmap further.
                 c->local_nsmallfree[sizeclass]++;
+                c->local_cachealloc -= size;
                 if(c->alloc[sizeclass] == s) {
                         // We own the span, so we can just add v to the freelist
                         runtime·markfreed(v);
                         ((MLink*)v)->next = s->freelist;
                         s->freelist = v;
                         s->ref--;
                 } else {
                         // Someone else owns this span.  Add to free queue.
                         runtime·MCache_Free(c, v, sizeclass, size);
                 }
@@ skipping 540 matching lines @@
                 // NOTE: asking to remove a finalizer when there currently isn't one set is OK.
                 runtime·removefinalizer(obj.data);
         }
         return;
 
 badfunc:
         runtime·printf("runtime.SetFinalizer: cannot pass %S to finalizer %S\n", *obj.type->string, *finalizer.type->string);
 throw:
         runtime·throw("runtime.SetFinalizer");
 }