From: Russ Cox <rsc@golang.org>
Date: Thu, 30 Sep 2010 18:09:19 +0000 (-0400)
Subject: runtime: serialize mcache allocation
X-Git-Tag: weekly.2010-10-13~85
X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=7389ab8d218fe7b7cf2ebdd232524a1ebd5a0b81;p=gostls13.git

runtime: serialize mcache allocation

Fixes racy regex-dna-parallel crashes.

R=r, r2
CC=golang-dev
https://golang.org/cl/2308042
---

diff --git a/src/pkg/runtime/malloc.goc b/src/pkg/runtime/malloc.goc
index fa7164ec57..604290b93b 100644
--- a/src/pkg/runtime/malloc.goc
+++ b/src/pkg/runtime/malloc.goc
@@ -236,9 +236,11 @@ allocmcache(void)
 {
 	MCache *c;
 
+	lock(&mheap);
 	c = FixAlloc_Alloc(&mheap.cachealloc);
 	mstats.mcache_inuse = mheap.cachealloc.inuse;
 	mstats.mcache_sys = mheap.cachealloc.sys;
+	unlock(&mheap);
 	return c;
 }