commit ffc87076dda9878cb2cc098149bae441d38b9268
author Calin Juravle <calin@google.com> Wed Apr 20 14:22:09 2016 +0100
committer Calin Juravle <calin@google.com> Thu Apr 28 16:15:04 2016 +0100
tree e587208d6a8e62532792add3e1ace6b4e6d73e0f
parent 97cbc9206e9adc473a90650ebdb5d620f517ff04

Split profile recording from jit compilation

We still use ProfileInfo objects to record profile information. That
gives us the flexibility to add the inline caches in the future and the
convenience of the already implemented GC.

If UseJIT is false and SaveProfilingInfo true, we will only record the
ProfileInfo and never launch compilation tasks.

Bug: 27916886

(cherry picked from commit e5de54cfab5f14ba0b8ff25d8d60901c7021943f)

Change-Id: I68afc181d71447895fb12346c1806e99bcab1de2

runtime/runtime.cc

diff --git a/runtime/runtime.cc b/runtime/runtime.cc
index f0510af..6f2ad5f 100644
--- a/runtime/runtime.cc
+++ b/runtime/runtime.cc
@@ -558,15 +558,21 @@
 
   started_ = true;
 
-  if (jit_options_->UseJIT()) {
+  // Create the JIT either if we have to use JIT compilation or save profiling info.
+  // TODO(calin): We use the JIT class as a proxy for JIT compilation and for
+  // recoding profiles. Maybe we should consider changing the name to be more clear it's
+  // not only about compiling. b/28295073.
+  if (jit_options_->UseJitCompilation() || jit_options_->GetSaveProfilingInfo()) {
     std::string error_msg;
     if (!IsZygote()) {
     // If we are the zygote then we need to wait until after forking to create the code cache
     // due to SELinux restrictions on r/w/x memory regions.
       CreateJit();
-    } else if (!jit::Jit::LoadCompilerLibrary(&error_msg)) {
-      // Try to load compiler pre zygote to reduce PSS. b/27744947
-      LOG(WARNING) << "Failed to load JIT compiler with error " << error_msg;
+    } else if (jit_options_->UseJitCompilation()) {
+      if (!jit::Jit::LoadCompilerLibrary(&error_msg)) {
+        // Try to load compiler pre zygote to reduce PSS. b/27744947
+        LOG(WARNING) << "Failed to load JIT compiler with error " << error_msg;
+      }
     }
   }
 
@@ -713,7 +719,11 @@
   // before fork aren't attributed to an app.
   heap_->ResetGcPerformanceInfo();
 
-  if (!is_system_server && !safe_mode_ && jit_options_->UseJIT() && jit_.get() == nullptr) {
+
+  if (!is_system_server &&
+      !safe_mode_ &&
+      (jit_options_->UseJitCompilation() || jit_options_->GetSaveProfilingInfo()) &&
+      jit_.get() == nullptr) {
     // Note that when running ART standalone (not zygote, nor zygote fork),
     // the jit may have already been created.
     CreateJit();
@@ -1016,7 +1026,8 @@
     // this case.
     // If runtime_options doesn't have UseJIT set to true then CreateFromRuntimeArguments returns
     // null and we don't create the jit.
-    jit_options_->SetUseJIT(false);
+    jit_options_->SetUseJitCompilation(false);
+    jit_options_->SetSaveProfilingInfo(false);
   }
 
   // Allocate a global table of boxed lambda objects <-> closures.
@@ -1996,4 +2007,14 @@
   Thread::SetJitSensitiveThread();
 }
 
+// Returns true if JIT compilations are enabled. GetJit() will be not null in this case.
+bool Runtime::UseJitCompilation() const {
+  return (jit_ != nullptr) && jit_->UseJitCompilation();
+}
+
+// Returns true if profile saving is enabled. GetJit() will be not null in this case.
+bool Runtime::SaveProfileInfo() const {
+  return (jit_ != nullptr) && jit_->SaveProfilingInfo();
+}
+
 }  // namespace art