[scudo] Scudo thread specific data refactor, part 3

Summary:
Previous parts: D38139, D38183.

In this part of the refactor, we abstract the Linux vs Android TSD dissociation
in favor of a Exclusive vs Shared one, allowing for easier platform introduction
and configuration.

Most of this change consist of shuffling the files around to reflect the new
organization.

We introduce `scudo_platform.h` where platform specific definition lie. This
involves the TSD model and the platform specific allocator parameters. In an
upcoming CL, those will be configurable via defines, but we currently stick
with conservative defaults.

Reviewers: alekseyshl, dvyukov

Reviewed By: alekseyshl, dvyukov

Subscribers: srhines, llvm-commits, mgorny

Differential Revision: https://reviews.llvm.org/D38244

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@314224 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 38 insertions, 0 deletions

diff --git a/lib/scudo/scudo_tsd_shared.inc b/lib/scudo/scudo_tsd_shared.inc
new file mode 100644
index 000000000..874942bba
--- /dev/null
+++ b/lib/scudo/scudo_tsd_shared.inc
@@ -0,0 +1,38 @@
+//===-- scudo_tsd_shared.inc ------------------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+///
+/// Scudo shared TSD fastpath functions implementation.
+///
+//===----------------------------------------------------------------------===//
+
+#ifndef SCUDO_TSD_H_
+# error "This file must be included inside scudo_tsd.h."
+#endif  // SCUDO_TSD_H_
+
+#if !SCUDO_TSD_EXCLUSIVE
+
+ALWAYS_INLINE void initThreadMaybe(bool MinimalInit = false) {
+  if (LIKELY(*get_android_tls_ptr()))
+    return;
+  initThread(MinimalInit);
+}
+
+ScudoTSD *getTSDAndLockSlow();
+
+ALWAYS_INLINE ScudoTSD *getTSDAndLock() {
+  ScudoTSD *TSD = reinterpret_cast<ScudoTSD *>(*get_android_tls_ptr());
+  CHECK(TSD && "No TSD associated with the current thread!");
+  // Try to lock the currently associated context.
+  if (TSD->tryLock())
+    return TSD;
+  // If it failed, go the slow path.
+  return getTSDAndLockSlow();
+}
+
+#endif  // !SCUDO_TSD_EXCLUSIVE