From: Dmitriy Vyukov <dvyukov@google.com>
Date: Wed, 14 Nov 2012 12:58:10 +0000 (+0400)
Subject: runtime/race: more precise handling of finalizers
X-Git-Tag: go1.1rc2~1872
X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=063c13a34cd64de8fe2577279be915ef7c33ab1f;p=gostls13.git

runtime/race: more precise handling of finalizers
Currently race detector runtime just disables race detection in the finalizer goroutine.
It has false positives when a finalizer writes to shared memory -- the race with finalizer is reported in a normal goroutine that accesses the same memory.
After this change I am going to synchronize the finalizer goroutine with the rest of the world in racefingo(). This is closer to what happens in reality and so
does not have false positives.
And also add README file with instructions how to build the runtime.

R=golang-dev, minux.ma, rsc
CC=golang-dev
https://golang.org/cl/6810095
---

diff --git a/src/pkg/runtime/mgc0.c b/src/pkg/runtime/mgc0.c
index ab68619d00..5ad09d53b1 100644
--- a/src/pkg/runtime/mgc0.c
+++ b/src/pkg/runtime/mgc0.c
@@ -1137,9 +1137,6 @@ runfinq(void)
 	byte *frame;
 	uint32 framesz, framecap, i;
 
-	if(raceenabled)
-		runtime·racefingo();
-
 	frame = nil;
 	framecap = 0;
 	for(;;) {
@@ -1156,6 +1153,8 @@ runfinq(void)
 			runtime·park(nil, nil, "finalizer wait");
 			continue;
 		}
+		if(raceenabled)
+			runtime·racefingo();
 		for(; fb; fb=next) {
 			next = fb->next;
 			for(i=0; i<fb->cnt; i++) {
diff --git a/src/pkg/runtime/race/README b/src/pkg/runtime/race/README
new file mode 100644
index 0000000000..8bedb09cdd
--- /dev/null
+++ b/src/pkg/runtime/race/README
@@ -0,0 +1,11 @@
+runtime/race package contains the data race detector runtime library.
+It is based on ThreadSanitizer race detector, that is currently a part of
+the LLVM project.
+
+To update the .syso files you need to:
+$ svn co http://llvm.org/svn/llvm-project/compiler-rt/trunk
+$ cd compiler-rt/lib/tsan/go
+$ ./buildgo.sh
+
+Tested with gcc 4.6.1 and 4.7.0.  On Windows it's built with 64-bit MinGW.
+
diff --git a/src/pkg/runtime/race/race_darwin_amd64.syso b/src/pkg/runtime/race/race_darwin_amd64.syso
index b323a71297..0caa119303 100644
Binary files a/src/pkg/runtime/race/race_darwin_amd64.syso and b/src/pkg/runtime/race/race_darwin_amd64.syso differ
diff --git a/src/pkg/runtime/race/race_linux_amd64.syso b/src/pkg/runtime/race/race_linux_amd64.syso
index ccc42e57ca..d58aea78a4 100644
Binary files a/src/pkg/runtime/race/race_linux_amd64.syso and b/src/pkg/runtime/race/race_linux_amd64.syso differ
diff --git a/src/pkg/runtime/race/race_windows_amd64.syso b/src/pkg/runtime/race/race_windows_amd64.syso
index 9aecde4458..df693d9b7b 100644
Binary files a/src/pkg/runtime/race/race_windows_amd64.syso and b/src/pkg/runtime/race/race_windows_amd64.syso differ