pprof: add goroutine blocking profiling
The profiler collects goroutine blocking information similar to Google Perf Tools.
You may see an example of the profile (converted to svg) attached to
http://code.google.com/p/go/issues/detail?id=3946
The public API changes are:
+pkg runtime, func BlockProfile([]BlockProfileRecord) (int, bool)
+pkg runtime, func SetBlockProfileRate(int)
+pkg runtime, method (*BlockProfileRecord) Stack() []uintptr
+pkg runtime, type BlockProfileRecord struct
+pkg runtime, type BlockProfileRecord struct, Count int64
+pkg runtime, type BlockProfileRecord struct, Cycles int64
+pkg runtime, type BlockProfileRecord struct, embedded StackRecord
R=rsc, dave, minux.ma, r
CC=gobot, golang-dev, r, remyoudompheng
https://golang.org/cl/6443115
diff --git a/src/pkg/runtime/runtime.h b/src/pkg/runtime/runtime.h
index 4bcd860..f808b59 100644
--- a/src/pkg/runtime/runtime.h
+++ b/src/pkg/runtime/runtime.h
@@ -642,6 +642,9 @@
void runtime·setcpuprofilerate(void(*)(uintptr*, int32), int32);
void runtime·usleep(uint32);
int64 runtime·cputicks(void);
+int64 runtime·tickspersecond(void);
+void runtime·blockevent(int64, int32);
+extern int64 runtime·blockprofilerate;
#pragma varargck argpos runtime·printf 1
#pragma varargck type "d" int32
