From c0e306ba339ce48f511e082fda8cc4cf73fbe0a3 Mon Sep 17 00:00:00 2001
From: Jon Coppeard <jcoppeard@mozilla.com>
Date: Thu, 1 Jun 2017 15:18:47 +0100
Subject: [PATCH] Bug 1352507 - Reset the profiling stack when the shell
 context owning it dies r=njn

---
 .../jit-test/tests/profiler/bug1352507-1.js   |  3 +
 .../jit-test/tests/profiler/bug1352507-2.js   |  3 +
 js/src/shell/js.cpp                           | 61 ++++++++++++++++---
 js/src/shell/jsshell.h                        |  3 +-
 4 files changed, 62 insertions(+), 8 deletions(-)
 create mode 100644 js/src/jit-test/tests/profiler/bug1352507-1.js
 create mode 100644 js/src/jit-test/tests/profiler/bug1352507-2.js

diff --git a/js/src/jit-test/tests/profiler/bug1352507-1.js b/js/src/jit-test/tests/profiler/bug1352507-1.js
new file mode 100644
index 000000000000..3289da864938
--- /dev/null
+++ b/js/src/jit-test/tests/profiler/bug1352507-1.js
@@ -0,0 +1,3 @@
+if (helperThreadCount() === 0)
+    quit();
+evalInWorker("enableGeckoProfiling()");
diff --git a/js/src/jit-test/tests/profiler/bug1352507-2.js b/js/src/jit-test/tests/profiler/bug1352507-2.js
new file mode 100644
index 000000000000..cf09062adf87
--- /dev/null
+++ b/js/src/jit-test/tests/profiler/bug1352507-2.js
@@ -0,0 +1,3 @@
+if (helperThreadCount() === 0)
+    quit();
+evalInCooperativeThread("enableGeckoProfiling()");
diff --git a/js/src/shell/js.cpp b/js/src/shell/js.cpp
index 4f752ffabe13..108d8e14727f 100644
--- a/js/src/shell/js.cpp
+++ b/js/src/shell/js.cpp
@@ -3430,6 +3430,11 @@ WorkerMain(void* arg)
 
     KillWatchdog(cx);
     JS_SetGrayGCRootsTracer(cx, nullptr, nullptr);
+
+    if (sc->geckoProfilingStack) {
+        MOZ_ALWAYS_TRUE(cx->runtime()->geckoProfiler().enable(false));
+        SetContextProfilingStack(cx, nullptr);
+    }
 }
 
 // Workers can spawn other workers, so we need a lock to access workerThreads.
@@ -5205,6 +5210,29 @@ IsLatin1(JSContext* cx, unsigned argc, Value* vp)
     return true;
 }
 
+static bool
+EnsureGeckoProfilingStackInstalled(JSContext* cx, ShellContext* sc)
+{
+    if (cx->runtime()->geckoProfiler().installed()) {
+        if (!sc->geckoProfilingStack) {
+            JS_ReportErrorASCII(cx, "Profiler already installed by another context");
+            return false;
+        }
+
+        return true;
+    }
+
+    MOZ_ASSERT(!sc->geckoProfilingStack);
+    sc->geckoProfilingStack = MakeUnique<PseudoStack>();
+    if (!sc->geckoProfilingStack) {
+        JS_ReportOutOfMemory(cx);
+        return false;
+    }
+
+    SetContextProfilingStack(cx, sc->geckoProfilingStack.get());
+    return true;
+}
+
 static bool
 EnableGeckoProfiling(JSContext* cx, unsigned argc, Value* vp)
 {
@@ -5212,14 +5240,19 @@ EnableGeckoProfiling(JSContext* cx, unsigned argc, Value* vp)
 
     ShellContext* sc = GetShellContext(cx);
 
-    // Disable before re-enabling; see the assertion in |GeckoProfiler::setProfilingStack|.
+    if (!EnsureGeckoProfilingStackInstalled(cx, sc))
+        return false;
+
+    // Disable before re-enabling; see the assertion in
+    // |GeckoProfiler::setProfilingStack|.
     if (cx->runtime()->geckoProfiler().installed())
         MOZ_ALWAYS_TRUE(cx->runtime()->geckoProfiler().enable(false));
 
-    SetContextProfilingStack(cx, &sc->geckoProfilingStack);
     cx->runtime()->geckoProfiler().enableSlowAssertions(false);
-    if (!cx->runtime()->geckoProfiler().enable(true))
+    if (!cx->runtime()->geckoProfiler().enable(true)) {
         JS_ReportErrorASCII(cx, "Cannot ensure single threaded execution in profiler");
+        return false;
+    }
 
     args.rval().setUndefined();
     return true;
@@ -5233,6 +5266,9 @@ EnableGeckoProfilingWithSlowAssertions(JSContext* cx, unsigned argc, Value* vp)
 
     ShellContext* sc = GetShellContext(cx);
 
+    if (!EnsureGeckoProfilingStackInstalled(cx, sc))
+        return false;
+
     if (cx->runtime()->geckoProfiler().enabled()) {
         // If profiling already enabled with slow assertions disabled,
         // this is a no-op.
@@ -5248,10 +5284,11 @@ EnableGeckoProfilingWithSlowAssertions(JSContext* cx, unsigned argc, Value* vp)
     if (cx->runtime()->geckoProfiler().installed())
         MOZ_ALWAYS_TRUE(cx->runtime()->geckoProfiler().enable(false));
 
-    SetContextProfilingStack(cx, &sc->geckoProfilingStack);
     cx->runtime()->geckoProfiler().enableSlowAssertions(true);
-    if (!cx->runtime()->geckoProfiler().enable(true))
+    if (!cx->runtime()->geckoProfiler().enable(true)) {
         JS_ReportErrorASCII(cx, "Cannot ensure single threaded execution in profiler");
+        return false;
+    }
 
     return true;
 }
@@ -5260,9 +5297,19 @@ static bool
 DisableGeckoProfiling(JSContext* cx, unsigned argc, Value* vp)
 {
     CallArgs args = CallArgsFromVp(argc, vp);
-    if (cx->runtime()->geckoProfiler().installed())
-        MOZ_ALWAYS_TRUE(cx->runtime()->geckoProfiler().enable(false));
     args.rval().setUndefined();
+
+    ShellContext* sc = GetShellContext(cx);
+
+    if (!cx->runtime()->geckoProfiler().installed())
+        return true;
+
+    if (!sc->geckoProfilingStack) {
+        JS_ReportErrorASCII(cx, "Profiler was not installed by this context");
+        return false;
+    }
+
+    MOZ_ALWAYS_TRUE(cx->runtime()->geckoProfiler().enable(false));
     return true;
 }
 
diff --git a/js/src/shell/jsshell.h b/js/src/shell/jsshell.h
index b4ceedd021e9..f33e158af299 100644
--- a/js/src/shell/jsshell.h
+++ b/js/src/shell/jsshell.h
@@ -171,6 +171,7 @@ using StackChars = Vector<char16_t, 0, SystemAllocPolicy>;
 struct ShellContext
 {
     explicit ShellContext(JSContext* cx);
+
     bool isWorker;
     double timeoutInterval;
     double startTime;
@@ -203,7 +204,7 @@ struct ShellContext
     js::shell::RCFile** errFilePtr;
     js::shell::RCFile** outFilePtr;
 
-    PseudoStack geckoProfilingStack;
+    UniquePtr<PseudoStack> geckoProfilingStack;
 
     OffThreadState offThreadState;