ART: Do not run verification under lock
Do not hold the object lock for the duration of the verification.
Instead, use the kStatusVerifying indicator to wait, similar to
resolution.
Bug: 27924355
Change-Id: Ie831f47dd830756a1b7002ca9c792f8ff67570dc
diff --git a/runtime/class_linker.cc b/runtime/class_linker.cc
index 32ad422..ff6778d 100644
--- a/runtime/class_linker.cc
+++ b/runtime/class_linker.cc
@@ -3715,10 +3715,6 @@
DCHECK(klass.Get() != nullptr);
DCHECK(supertype.Get() != nullptr);
- StackHandleScope<1> hs(self);
- // Acquire lock to prevent races on verifying the super class.
- ObjectLock<mirror::Class> super_lock(self, supertype);
-
if (!supertype->IsVerified() && !supertype->IsErroneous()) {
VerifyClass(self, supertype);
}
@@ -3732,6 +3728,7 @@
PrettyDescriptor(klass.Get()).c_str(),
PrettyDescriptor(supertype.Get()).c_str());
LOG(WARNING) << error_msg << " in " << klass->GetDexCache()->GetLocation()->ToModifiedUtf8();
+ StackHandleScope<1> hs(self);
Handle<mirror::Throwable> cause(hs.NewHandle(self->GetException()));
if (cause.Get() != nullptr) {
// Set during VerifyClass call (if at all).
@@ -3746,44 +3743,57 @@
if (Runtime::Current()->IsAotCompiler()) {
Runtime::Current()->GetCompilerCallbacks()->ClassRejected(ref);
}
+ // Need to grab the lock to change status.
+ ObjectLock<mirror::Class> super_lock(self, klass);
mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self);
return false;
}
void ClassLinker::VerifyClass(Thread* self, Handle<mirror::Class> klass, LogSeverity log_level) {
- // TODO: assert that the monitor on the Class is held
- ObjectLock<mirror::Class> lock(self, klass);
+ {
+ // TODO: assert that the monitor on the Class is held
+ ObjectLock<mirror::Class> lock(self, klass);
- // Don't attempt to re-verify if already sufficiently verified.
- if (klass->IsVerified()) {
- EnsureSkipAccessChecksMethods(klass);
- return;
- }
- if (klass->IsCompileTimeVerified() && Runtime::Current()->IsAotCompiler()) {
- return;
- }
+ // Is somebody verifying this now?
+ mirror::Class::Status old_status = klass->GetStatus();
+ while (old_status == mirror::Class::kStatusVerifying ||
+ old_status == mirror::Class::kStatusVerifyingAtRuntime) {
+ lock.WaitIgnoringInterrupts();
+ CHECK_GT(klass->GetStatus(), old_status);
+ old_status = klass->GetStatus();
+ }
- // The class might already be erroneous, for example at compile time if we attempted to verify
- // this class as a parent to another.
- if (klass->IsErroneous()) {
- ThrowEarlierClassFailure(klass.Get());
- return;
- }
+ // The class might already be erroneous, for example at compile time if we attempted to verify
+ // this class as a parent to another.
+ if (klass->IsErroneous()) {
+ ThrowEarlierClassFailure(klass.Get());
+ return;
+ }
- if (klass->GetStatus() == mirror::Class::kStatusResolved) {
- mirror::Class::SetStatus(klass, mirror::Class::kStatusVerifying, self);
- } else {
- CHECK_EQ(klass->GetStatus(), mirror::Class::kStatusRetryVerificationAtRuntime)
- << PrettyClass(klass.Get());
- CHECK(!Runtime::Current()->IsAotCompiler());
- mirror::Class::SetStatus(klass, mirror::Class::kStatusVerifyingAtRuntime, self);
- }
+ // Don't attempt to re-verify if already sufficiently verified.
+ if (klass->IsVerified()) {
+ EnsureSkipAccessChecksMethods(klass);
+ return;
+ }
+ if (klass->IsCompileTimeVerified() && Runtime::Current()->IsAotCompiler()) {
+ return;
+ }
- // Skip verification if disabled.
- if (!Runtime::Current()->IsVerificationEnabled()) {
- mirror::Class::SetStatus(klass, mirror::Class::kStatusVerified, self);
- EnsureSkipAccessChecksMethods(klass);
- return;
+ if (klass->GetStatus() == mirror::Class::kStatusResolved) {
+ mirror::Class::SetStatus(klass, mirror::Class::kStatusVerifying, self);
+ } else {
+ CHECK_EQ(klass->GetStatus(), mirror::Class::kStatusRetryVerificationAtRuntime)
+ << PrettyClass(klass.Get());
+ CHECK(!Runtime::Current()->IsAotCompiler());
+ mirror::Class::SetStatus(klass, mirror::Class::kStatusVerifyingAtRuntime, self);
+ }
+
+ // Skip verification if disabled.
+ if (!Runtime::Current()->IsVerificationEnabled()) {
+ mirror::Class::SetStatus(klass, mirror::Class::kStatusVerified, self);
+ EnsureSkipAccessChecksMethods(klass);
+ return;
+ }
}
// Verify super class.
@@ -3856,6 +3866,10 @@
log_level,
&error_msg);
}
+
+ // Verification is done, grab the lock again.
+ ObjectLock<mirror::Class> lock(self, klass);
+
if (preverified || verifier_failure != verifier::MethodVerifier::kHardFailure) {
if (!preverified && verifier_failure != verifier::MethodVerifier::kNoFailure) {
VLOG(class_linker) << "Soft verification failure in class " << PrettyDescriptor(klass.Get())