From: Tudor Bosman <tudorb@fb.com>
Date: Tue, 3 Dec 2013 21:09:13 +0000 (-0800)
Subject: Change exception tracer to use per-thread caching in libunwind
X-Git-Tag: v0.22.0~775
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=ec61097ac903e471c1440b3c09818d8a1748de6d;p=folly.git

Change exception tracer to use per-thread caching in libunwind

Summary: Because the global cache is slow and contends on locks.

Test Plan: testinproduction

Reviewed By: philipp@fb.com

FB internal diff: D1081259
---

diff --git a/folly/experimental/exception_tracer/ExceptionTracerLib.cpp b/folly/experimental/exception_tracer/ExceptionTracerLib.cpp
index eab33fd3..3813c6ad 100644
--- a/folly/experimental/exception_tracer/ExceptionTracerLib.cpp
+++ b/folly/experimental/exception_tracer/ExceptionTracerLib.cpp
@@ -81,6 +81,8 @@ void initialize() {
       !orig_cxa_end_catch || !orig_rethrow_exception) {
     abort();  // what else can we do?
   }
+
+  initStackTrace();
 }
 
 }  // namespace
diff --git a/folly/experimental/exception_tracer/StackTrace.h b/folly/experimental/exception_tracer/StackTrace.h
index 6b2ab3c7..b7354498 100644
--- a/folly/experimental/exception_tracer/StackTrace.h
+++ b/folly/experimental/exception_tracer/StackTrace.h
@@ -75,6 +75,11 @@ void clearStack(StackTraceStack** head);
  */
 int moveTop(StackTraceStack** from, StackTraceStack** to);
 
+/**
+ * Initialize the stack tracing code.
+ */
+void initStackTrace();
+
 #ifdef __cplusplus
 }  /* extern "C" */
 #endif