From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 2181) id 3BDAD385740E; Wed, 14 Sep 2022 22:04:19 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 3BDAD385740E DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org; s=default; t=1663193059; bh=6N/FrTVZdv2K4rdNeqQfcB4xdrmDbU1lQ6TKZvd2K3k=; h=From:To:Subject:Date:From; b=qWlkYde3E9LqwQAFglkXJoMaB6p7LKPmVzfLBZ7H/aOCDo7Eo/86in4AQkp5/QFx7 wpJOJ/ALBslyasWW+fDZHMETOxJ9FWmh/Gl12hwzo36iXkaxOZPfA7qxpjmFdMIldG avGYG47oEnIDCJTJuM9N+auajXE/FmvF1ynxONEA= MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="utf-8" From: Jonathan Wakely To: gcc-cvs@gcc.gnu.org, libstdc++-cvs@gcc.gnu.org Subject: [gcc r13-2677] libstdc++: Add TSan annotations to std::atomic> X-Act-Checkin: gcc X-Git-Author: Jonathan Wakely X-Git-Refname: refs/heads/master X-Git-Oldrev: 7f1e3d06bb9a39fb42afd4d0ea1a103fe239b1cb X-Git-Newrev: 0abc63a5ea4550c9e75e81b05a153dfb4b234446 Message-Id: <20220914220419.3BDAD385740E@sourceware.org> Date: Wed, 14 Sep 2022 22:04:19 +0000 (GMT) List-Id: https://gcc.gnu.org/g:0abc63a5ea4550c9e75e81b05a153dfb4b234446 commit r13-2677-g0abc63a5ea4550c9e75e81b05a153dfb4b234446 Author: Jonathan Wakely Date: Wed Sep 14 19:11:22 2022 +0100 libstdc++: Add TSan annotations to std::atomic> This adds annotations to std::atomic> to enable TSan to understand the custom locking. Without this, TSan reports data races for accesses to the _M_ptr member, even though those are correctly synchronized using atomic operations on the tagged pointer. libstdc++-v3/ChangeLog: * include/bits/shared_ptr_atomic.h (_GLIBCXX_TSAN_MUTEX_DESTROY) (_GLIBCXX_TSAN_MUTEX_PRE_LOCK, _GLIBCXX_TSAN_MUTEX_POST_LOCK) (_GLIBCXX_TSAN_MUTEX_PRE_UNLOCK, _GLIBCXX_TSAN_MUTEX_POST_UNLOCK) (_GLIBCXX_TSAN_MUTEX_PRE_SIGNAL, _GLIBCXX_TSAN_MUTEX_POST_SIGNAL): Define macros for TSan annotation functions. (_Sp_atomic::_Atomic_count): Add annotations. Diff: --- libstdc++-v3/include/bits/shared_ptr_atomic.h | 38 +++++++++++++++++++++++++++ 1 file changed, 38 insertions(+) diff --git a/libstdc++-v3/include/bits/shared_ptr_atomic.h b/libstdc++-v3/include/bits/shared_ptr_atomic.h index d4bd712fc7d..4580807f42c 100644 --- a/libstdc++-v3/include/bits/shared_ptr_atomic.h +++ b/libstdc++-v3/include/bits/shared_ptr_atomic.h @@ -32,6 +32,30 @@ #include +#if defined _GLIBCXX_TSAN && __has_include() +#include +#define _GLIBCXX_TSAN_MUTEX_DESTROY(X) \ + __tsan_mutex_destroy(X, __tsan_mutex_not_static) +#define _GLIBCXX_TSAN_MUTEX_PRE_LOCK(X) \ + __tsan_mutex_pre_lock(X, __tsan_mutex_not_static) +#define _GLIBCXX_TSAN_MUTEX_POST_LOCK(X) \ + __tsan_mutex_post_lock(X, __tsan_mutex_not_static, 0) +#define _GLIBCXX_TSAN_MUTEX_PRE_UNLOCK(X) \ + __tsan_mutex_pre_unlock(X, __tsan_mutex_not_static) +#define _GLIBCXX_TSAN_MUTEX_POST_UNLOCK(X) \ + __tsan_mutex_post_unlock(X, __tsan_mutex_not_static) +#define _GLIBCXX_TSAN_MUTEX_PRE_SIGNAL(X) __tsan_mutex_pre_signal(X, 0) +#define _GLIBCXX_TSAN_MUTEX_POST_SIGNAL(X) __tsan_mutex_post_signal(X, 0) +#else +#define _GLIBCXX_TSAN_MUTEX_DESTROY(X) +#define _GLIBCXX_TSAN_MUTEX_PRE_LOCK(X) +#define _GLIBCXX_TSAN_MUTEX_POST_LOCK(X) +#define _GLIBCXX_TSAN_MUTEX_PRE_UNLOCK(X) +#define _GLIBCXX_TSAN_MUTEX_POST_UNLOCK(X) +#define _GLIBCXX_TSAN_MUTEX_PRE_SIGNAL(X) +#define _GLIBCXX_TSAN_MUTEX_POST_SIGNAL(X) +#endif + namespace std _GLIBCXX_VISIBILITY(default) { _GLIBCXX_BEGIN_NAMESPACE_VERSION @@ -377,6 +401,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION ~_Atomic_count() { auto __val = _M_val.load(memory_order_relaxed); + _GLIBCXX_TSAN_MUTEX_DESTROY(&_M_val); __glibcxx_assert(!(__val & _S_lock_bit)); if (auto __pi = reinterpret_cast(__val)) { @@ -406,6 +431,8 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION __current = _M_val.load(memory_order_relaxed); } + _GLIBCXX_TSAN_MUTEX_PRE_LOCK(&_M_val); + while (!_M_val.compare_exchange_strong(__current, __current | _S_lock_bit, __o, @@ -416,6 +443,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION #endif __current = __current & ~_S_lock_bit; } + _GLIBCXX_TSAN_MUTEX_POST_LOCK(&_M_val); return reinterpret_cast(__current); } @@ -423,7 +451,9 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION void unlock(memory_order __o) const noexcept { + _GLIBCXX_TSAN_MUTEX_PRE_UNLOCK(&_M_val); _M_val.fetch_sub(1, __o); + _GLIBCXX_TSAN_MUTEX_POST_UNLOCK(&_M_val); } // Swaps the values of *this and __c, and unlocks *this. @@ -434,7 +464,9 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION if (__o != memory_order_seq_cst) __o = memory_order_release; auto __x = reinterpret_cast(__c._M_pi); + _GLIBCXX_TSAN_MUTEX_PRE_UNLOCK(&_M_val); __x = _M_val.exchange(__x, __o); + _GLIBCXX_TSAN_MUTEX_POST_UNLOCK(&_M_val); __c._M_pi = reinterpret_cast(__x & ~_S_lock_bit); } @@ -443,20 +475,26 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION void _M_wait_unlock(memory_order __o) const noexcept { + _GLIBCXX_TSAN_MUTEX_PRE_UNLOCK(&_M_val); auto __v = _M_val.fetch_sub(1, memory_order_relaxed); + _GLIBCXX_TSAN_MUTEX_POST_UNLOCK(&_M_val); _M_val.wait(__v & ~_S_lock_bit, __o); } void notify_one() noexcept { + _GLIBCXX_TSAN_MUTEX_PRE_SIGNAL(&_M_val); _M_val.notify_one(); + _GLIBCXX_TSAN_MUTEX_POST_SIGNAL(&_M_val); } void notify_all() noexcept { + _GLIBCXX_TSAN_MUTEX_PRE_SIGNAL(&_M_val); _M_val.notify_all(); + _GLIBCXX_TSAN_MUTEX_POST_SIGNAL(&_M_val); } #endif