Index: third_party/tcmalloc/chromium/src/base/spinlock_internal.cc |
=================================================================== |
--- third_party/tcmalloc/chromium/src/base/spinlock_internal.cc (revision 0) |
+++ third_party/tcmalloc/chromium/src/base/spinlock_internal.cc (revision 0) |
@@ -0,0 +1,77 @@ |
+/* Copyright (c) 2010, Google Inc. |
+ * All rights reserved. |
+ * |
+ * Redistribution and use in source and binary forms, with or without |
+ * modification, are permitted provided that the following conditions are |
+ * met: |
+ * |
+ * * Redistributions of source code must retain the above copyright |
+ * notice, this list of conditions and the following disclaimer. |
+ * * Redistributions in binary form must reproduce the above |
+ * copyright notice, this list of conditions and the following disclaimer |
+ * in the documentation and/or other materials provided with the |
+ * distribution. |
+ * * Neither the name of Google Inc. nor the names of its |
+ * contributors may be used to endorse or promote products derived from |
+ * this software without specific prior written permission. |
+ * |
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
+ */ |
+ |
+// The OS-specific header included below must provide two calls: |
+// base::internal::SpinLockDelay() and base::internal::SpinLockWake(). |
+// See spinlock_internal.h for the spec of SpinLockWake(). |
+ |
+// void SpinLockDelay(volatile Atomic32 *w, int32 value, int loop) |
+// SpinLockDelay() generates an apprproate spin delay on iteration "loop" of a |
+// spin loop on location *w, whose previously observed value was "value". |
+// SpinLockDelay() may do nothing, may yield the CPU, may sleep a clock tick, |
+// or may wait for a delay that can be truncated by a call to SpinlockWake(w). |
+// In all cases, it must return in bounded time even if SpinlockWake() is not |
+// called. |
+ |
+#include "base/spinlock_internal.h" |
+ |
+#if defined(_WIN32) |
+#include "base/spinlock_win32-inl.h" |
+#elif defined(__linux__) |
+#include "base/spinlock_linux-inl.h" |
+#else |
+#include "base/spinlock_posix-inl.h" |
+#endif |
+ |
+namespace base { |
+namespace internal { |
+ |
+// See spinlock_internal.h for spec. |
+int32 SpinLockWait(volatile Atomic32 *w, int n, |
+ const SpinLockWaitTransition trans[]) { |
+ int32 v; |
+ bool done = false; |
+ for (int loop = 0; !done; loop++) { |
+ v = base::subtle::Acquire_Load(w); |
+ int i; |
+ for (i = 0; i != n && v != trans[i].from; i++) { |
+ } |
+ if (i == n) { |
+ SpinLockDelay(w, v, loop); // no matching transition |
+ } else if (trans[i].to == v || // null transition |
+ base::subtle::Acquire_CompareAndSwap(w, v, trans[i].to) == v) { |
+ done = trans[i].done; |
+ } |
+ } |
+ return v; |
+} |
+ |
+} // namespace internal |
+} // namespace base |
Property changes on: third_party/tcmalloc/chromium/src/base/spinlock_internal.cc |
___________________________________________________________________ |
Added: svn:eol-style |
+ LF |