Add Clang Thread Safety Annotations

Author: jiridanek

CMakeLists.txt

@@ -60,7 +60,7 @@ set(C_WARNING_GNU -Wall -Wextra -Wpedantic -pedantic-errors
         -Wno-empty-body -Wno-unused-parameter  -Wno-missing-field-initializers -Wno-sign-compare -Wno-type-limits)
 set(C_WARNING_Clang -Wall -Wextra -Wpedantic
         -Wstrict-prototypes -Wold-style-definition
-        -Wno-unused-parameter -Wno-missing-field-initializers -Wno-sign-compare -Wno-language-extension-token)
+        -Wthread-safety -Wno-unused-parameter -Wno-missing-field-initializers -Wno-sign-compare -Wno-language-extension-token)
 
 # Set default build type. Must use FORCE because project() sets default to ""
 if (NOT CMAKE_BUILD_TYPE)
@@ -137,22 +137,23 @@ if(NOT DEFINED VERSION)
       execute_process(COMMAND ${GIT_EXECUTABLE} rev-parse --abbrev-ref HEAD
                       OUTPUT_VARIABLE BRANCH_NAME
                       OUTPUT_STRIP_TRAILING_WHITESPACE)
-                      
+
       if (BRANCH_NAME STREQUAL "HEAD")
         # You are perhaps on a detached tag or commit
         # Get the tag name and use it as the version
         execute_process(COMMAND ${GIT_EXECUTABLE} describe --tags --dirty=-modified --always
-              OUTPUT_VARIABLE DEFAULT_VERSION
-              RESULT_VARIABLE GIT_RESULT
-              OUTPUT_STRIP_TRAILING_WHITESPACE)
-                
+                      OUTPUT_VARIABLE DEFAULT_VERSION
+                      RESULT_VARIABLE GIT_RESULT
+                      OUTPUT_STRIP_TRAILING_WHITESPACE)
+
+
         # You might sometimes get a fatal error when running the above command (when this is not a git repo).
         # GIT_RESULT will contain the result of last child process. It will be zero if successful.
         if (GIT_RESULT EQUAL 0)
             # Git succeeded, we will use the DEFAULT_VERSION as the QPID_DISPATCH_VERSION
             set(QPID_DISPATCH_VERSION ${DEFAULT_VERSION})
          else()
-            # The git command failed, set QPID_DISPATCH_VERSION to "UNKNOWN" 
+            # The git command failed, set QPID_DISPATCH_VERSION to "UNKNOWN"
             set(QPID_DISPATCH_VERSION "UNKNOWN")
          endif(GIT_RESULT EQUAL 0)
       else(BRANCH_NAME STREQUAL "HEAD")
@@ -164,13 +165,13 @@ if(NOT DEFINED VERSION)
                           OUTPUT_VARIABLE COMMIT_SHA
                           OUTPUT_STRIP_TRAILING_WHITESPACE)
           message(STATUS "COMMIT_SHA is ${COMMIT_SHA}")
-          set(QPID_DISPATCH_VERSION "${COMMIT_SHA}(${BRANCH_NAME})")      
+          set(QPID_DISPATCH_VERSION "${COMMIT_SHA}(${BRANCH_NAME})")
       endif(BRANCH_NAME STREQUAL "HEAD")
    else(Git_FOUND)
        # Git executable was not available, we will not be able to determine the version, just set it to "UNKNOWN"
        set(QPID_DISPATCH_VERSION "UNKNOWN")
    endif(Git_FOUND)
-   
+
 else(NOT DEFINED VERSION)
 
    # What if VERSION is defined but someone passed in an empty value for VERSION? Deal with that case here.
@@ -183,7 +184,7 @@ else(NOT DEFINED VERSION)
       else()
           set(QPID_DISPATCH_VERSION ${VERSION})
       endif()
-   endif(VERSION STREQUAL "")  
+   endif(VERSION STREQUAL "")
 endif(NOT DEFINED VERSION)
 
 message(STATUS "Setting skupper-router version to ${QPID_DISPATCH_VERSION}")

include/qpid/dispatch/internal/thread_annotations.h

@@ -0,0 +1,86 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+// Copyright 2017 The Fuchsia Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#pragma once
+
+// This header defines thread annotation macros to be used everywhere in Zircon
+// outside of publicly exposed headers. See system/public/zircon/compiler.h for
+// the publicly exported macros.
+
+// The thread safety analysis system is documented at
+// http://clang.llvm.org/docs/ThreadSafetyAnalysis.html and its use in Zircon is documented at
+// docs/thread_annotations.md.  The macros we use are:
+//
+// TA_CAP(x)                    |x| is the capability this type represents, e.g. "mutex".
+// TA_GUARDED(x)                the annotated variable is guarded by the capability (e.g. lock) |x|
+// TA_ACQ(x)                    function acquires the mutex |x|
+// TA_ACQ_SHARED(x)             function acquires the mutex |x| for shared reading
+// TA_ACQ_BEFORE(x)             Indicates that if both this mutex and muxex |x| are to be acquired,
+//                              that this mutex must be acquired before mutex |x|.
+// TA_ACQ_AFTER(x)              Indicates that if both this mutex and muxex |x| are to be acquired,
+//                              that this mutex must be acquired after mutex |x|.
+// TA_TRY_ACQ(bool, x)          function acquires the mutex |x| if the function returns |bool|
+// TA_TRY_ACQ_SHARED(bool, x)   function acquires the mutex |x| for shared reading if the function
+//                              returns |bool|
+// TA_REL(x)                    function releases the mutex |x|
+// TA_REL_SHARED(x)             function releases the shared for reading mutex |x|
+// TA_ASSERT(x)                 function asserts that |x| is held
+// TA_ASSERT_SHARED(x)          function asserts that |x| is held for shared reading
+// TA_REQ(x)                    function requires that the caller hold the mutex |x|
+// TA_REQ_SHARED(x)             function requires that the caller hold the mutex |x| for shared
+// reading TA_EXCL(x)                   function requires that the caller not be holding the mutex
+// |x| TA_RET_CAP(x)                function returns a reference to the mutex |x| TA_SCOPED_CAP type
+// represents a scoped or RAII-style wrapper around a capability TA_NO_THREAD_SAFETY_ANALYSIS
+// function is excluded entirely from thread safety analysis
+
+#ifdef __clang__
+#define TA_SUPPRESS _Pragma("clang diagnostic ignored \"-Wthread-safety-analysis\"")
+#else
+#define TA_SUPPRESS
+#endif
+
+#ifdef __clang__
+#define THREAD_ANNOTATION(x) __attribute__((x))
+#else
+#define THREAD_ANNOTATION(x)
+#endif
+
+#define TA_CAP(x)                    THREAD_ANNOTATION(capability(x))
+#define TA_GUARDED(x)                THREAD_ANNOTATION(guarded_by(x))
+#define TA_ACQ(...)                  THREAD_ANNOTATION(acquire_capability(__VA_ARGS__))
+#define TA_ACQ_SHARED(...)           THREAD_ANNOTATION(acquire_shared_capability(__VA_ARGS__))
+#define TA_ACQ_BEFORE(...)           THREAD_ANNOTATION(acquired_before(__VA_ARGS__))
+#define TA_ACQ_AFTER(...)            THREAD_ANNOTATION(acquired_after(__VA_ARGS__))
+#define TA_TRY_ACQ(...)              THREAD_ANNOTATION(try_acquire_capability(__VA_ARGS__))
+#define TA_TRY_ACQ_SHARED(...)       THREAD_ANNOTATION(try_acquire_shared_capability(__VA_ARGS__))
+#define TA_REL(...)                  THREAD_ANNOTATION(release_capability(__VA_ARGS__))
+#define TA_REL_SHARED(...)           THREAD_ANNOTATION(release_shared_capability(__VA_ARGS__))
+#define TA_REL_GENERIC(...)          THREAD_ANNOTATION(release_generic_capability(__VA_ARGS__))
+#define TA_ASSERT(...)               THREAD_ANNOTATION(assert_capability(__VA_ARGS__))
+#define TA_ASSERT_SHARED(...)        THREAD_ANNOTATION(assert_shared_capability(__VA_ARGS__))
+#define TA_REQ(...)                  THREAD_ANNOTATION(requires_capability(__VA_ARGS__))
+#define TA_REQ_SHARED(...)           THREAD_ANNOTATION(requires_shared_capability(__VA_ARGS__))
+#define TA_EXCL(...)                 THREAD_ANNOTATION(locks_excluded(__VA_ARGS__))
+#define TA_RET_CAP(x)                THREAD_ANNOTATION(lock_returned(x))
+#define TA_SCOPED_CAP                THREAD_ANNOTATION(scoped_lockable)
+#define TA_NO_THREAD_SAFETY_ANALYSIS THREAD_ANNOTATION(no_thread_safety_analysis)

include/qpid/dispatch/threading.h

@@ -26,38 +26,40 @@
 #include <assert.h>
 #include <pthread.h>
 
-typedef struct sys_mutex_t sys_mutex_t;
+#include "qpid/dispatch/internal/thread_annotations.h"
+
+typedef struct sys_mutex_t TA_CAP("mutex") sys_mutex_t;
 struct sys_mutex_t {
     pthread_mutex_t mutex;
 };
 
 void sys_mutex_init(sys_mutex_t *mutex);
 void sys_mutex_free(sys_mutex_t *mutex);
-void sys_mutex_lock(sys_mutex_t *mutex);
-void sys_mutex_unlock(sys_mutex_t *mutex);
+void sys_mutex_lock(sys_mutex_t *mutex) TA_ACQ(*mutex);
+void sys_mutex_unlock(sys_mutex_t *mutex) TA_REL(*mutex);
 
-typedef struct sys_cond_t sys_cond_t;
+typedef struct sys_cond_t TA_CAP("cond") sys_cond_t;
 struct sys_cond_t {
     pthread_cond_t cond;
 };
 
 void sys_cond_init(sys_cond_t *cond);
 void sys_cond_free(sys_cond_t *cond);
-void sys_cond_wait(sys_cond_t *cond, sys_mutex_t *held_mutex);
+void sys_cond_wait(sys_cond_t *cond, sys_mutex_t *held_mutex) TA_REQ(*held_mutex);
 void sys_cond_signal(sys_cond_t *cond);
 void sys_cond_signal_all(sys_cond_t *cond);
 
 
-typedef struct sys_rwlock_t sys_rwlock_t;
+typedef struct sys_rwlock_t TA_CAP("rwlock") sys_rwlock_t;
 struct sys_rwlock_t {
     pthread_rwlock_t lock;
 };
 
 void sys_rwlock_init(sys_rwlock_t *lock);
 void sys_rwlock_free(sys_rwlock_t *lock);
-void sys_rwlock_wrlock(sys_rwlock_t *lock);
-void sys_rwlock_rdlock(sys_rwlock_t *lock);
-void sys_rwlock_unlock(sys_rwlock_t *lock);
+void sys_rwlock_wrlock(sys_rwlock_t *lock) TA_ACQ(*lock);
+void sys_rwlock_rdlock(sys_rwlock_t *lock) TA_ACQ_SHARED(*lock);
+void sys_rwlock_unlock(sys_rwlock_t *lock) TA_REL_GENERIC(*lock);
 
 typedef enum {
     SYS_THREAD_MAIN,
@@ -108,16 +110,16 @@ typedef enum {
     SYS_THREAD_PROACTOR_MODE_TIMER = SYS_THREAD_PROACTOR_MODE_OTHER,
 } sys_thread_proactor_mode_t;
 
-typedef struct sys_spinlock_t sys_spinlock_t;
+typedef struct sys_spinlock_t TA_CAP("spinlock") sys_spinlock_t;
 struct sys_spinlock_t {
     pthread_mutexattr_t attr;
     pthread_mutex_t     lock;
 };
 
 void sys_spinlock_init(sys_spinlock_t *lock);
 void sys_spinlock_free(sys_spinlock_t *lock);
-void sys_spinlock_lock(sys_spinlock_t *lock);
-void sys_spinlock_unlock(sys_spinlock_t *lock);
+void sys_spinlock_lock(sys_spinlock_t *lock) TA_ACQ(*lock);
+void sys_spinlock_unlock(sys_spinlock_t *lock) TA_REL(*lock);
 
 
 typedef struct sys_thread_t sys_thread_t;

src/dispatch.c

@@ -384,8 +384,8 @@ void qd_dispatch_free(qd_dispatch_t *qd)
 }
 
 
-QD_EXPORT void qd_dispatch_router_lock(qd_dispatch_t *qd) { sys_mutex_lock(&qd->router->lock); }
-QD_EXPORT void qd_dispatch_router_unlock(qd_dispatch_t *qd) { sys_mutex_unlock(&qd->router->lock); }
+QD_EXPORT void qd_dispatch_router_lock(qd_dispatch_t *qd) TA_ACQ(qd->router->lock) { sys_mutex_lock(&qd->router->lock); }
+QD_EXPORT void qd_dispatch_router_unlock(qd_dispatch_t *qd) TA_REL(qd->router->lock) { sys_mutex_unlock(&qd->router->lock); }
 
 qdr_core_t* qd_dispatch_router_core(const qd_dispatch_t *qd)
 {

src/entity_cache.c

@@ -87,7 +87,8 @@ void qd_entity_cache_remove(const char *type, void *object) { push_event(REMOVE,
 // Locks the entity cache so entities can be updated safely (prevent entities from being deleted.)
 // Do not process any entities if return error code != 0
 // Must call qd_entity_refresh_end when done, regardless of error code.
-QD_EXPORT qd_error_t qd_entity_refresh_begin(PyObject *list) {
+QD_EXPORT qd_error_t qd_entity_refresh_begin(PyObject *list) TA_ACQ(event_lock) TA_NO_THREAD_SAFETY_ANALYSIS
+{
     qd_error_clear();
     sys_mutex_lock(&event_lock);
     entity_event_t *event = DEQ_HEAD(event_list);
@@ -104,7 +105,7 @@ QD_EXPORT qd_error_t qd_entity_refresh_begin(PyObject *list) {
     return qd_error_code();
 }
 
-QD_EXPORT void qd_entity_refresh_end(void)
+QD_EXPORT void qd_entity_refresh_end(void) TA_REL(event_lock)
 {
     sys_mutex_unlock(&event_lock);
 }

src/log.c

@@ -47,6 +47,7 @@
 const char *QD_LOG_STATS_TYPE = "logStats";
 
 static qd_log_source_t      *default_log_source=0;
+static sys_mutex_t           log_source_lock;
 
 int qd_log_max_len(void)
 {
@@ -177,14 +178,16 @@ void qd_log_formatted_time(const struct timeval *time, char *buf, size_t buflen)
     snprintf(buf, buflen, fmt, time->tv_usec);
 }
 
-static log_sink_t* find_log_sink_lh(const char* name) {
+static log_sink_t *find_log_sink_lh(const char *name) TA_REQ(log_source_lock)
+{
     log_sink_t* sink = DEQ_HEAD(sink_list);
     DEQ_FIND(sink, strcmp(sink->name, name) == 0);
     return sink;
 }
 
 // Must hold the log_source_lock
-static void log_sink_free_lh(log_sink_t* sink) {
+static void log_sink_free_lh(log_sink_t *sink) TA_REQ(log_source_lock)
+{
     if (!sink) return;
     assert(sink->ref_count);
 
@@ -199,7 +202,8 @@ static void log_sink_free_lh(log_sink_t* sink) {
     }
 }
 
-static log_sink_t* log_sink_lh(const char* name) {
+static log_sink_t *log_sink_lh(const char *name) TA_REQ(log_source_lock)
+{
     log_sink_t* sink = find_log_sink_lh(name);
     if (sink) {
         sys_atomic_inc(&sink->ref_count);
@@ -393,7 +397,8 @@ static void write_log_lh(qd_log_source_t *log_source, qd_log_entry_t *entry)
 }
 
 /// Reset the log source to the default state
-static void qd_log_source_defaults(qd_log_source_t *log_source) {
+static void qd_log_source_defaults(qd_log_source_t *log_source) TA_REQ(log_source_lock)
+{
     log_source->mask = -1;
     log_source->includeTimestamp = -1;
     log_source->includeSource = -1;
@@ -402,7 +407,7 @@ static void qd_log_source_defaults(qd_log_source_t *log_source) {
 }
 
 /// Caller must hold the log_source_lock
-static qd_log_source_t *qd_log_source_lh(qd_log_module_t module)
+static qd_log_source_t *qd_log_source_lh(qd_log_module_t module) TA_REQ(log_source_lock)
 {
     qd_log_source_t *log_source = log_sources[module];
 
@@ -437,7 +442,7 @@ qd_log_source_t *qd_log_source_reset(qd_log_module_t module)
     return src;
 }
 
-static void qd_log_source_free_lh(qd_log_module_t module)
+static void qd_log_source_free_lh(qd_log_module_t module) TA_REQ(log_source_lock)
 {
     qd_log_source_t *src = log_sources[module];
     if (src) {
@@ -569,7 +574,7 @@ QD_EXPORT PyObject *qd_log_recent_py(long limit) {
     return NULL;
 }
 
-void qd_log_initialize(void)
+void qd_log_initialize(void) TA_NO_THREAD_SAFETY_ANALYSIS
 {
     DEQ_INIT(entries);
     DEQ_INIT(sink_list);
@@ -589,8 +594,8 @@ void qd_log_initialize(void)
     default_log_source->sink = log_sink_lh(SINK_STDERR);
 }
 
-
-void qd_log_finalize(void) {
+void qd_log_finalize(void) TA_NO_THREAD_SAFETY_ANALYSIS
+{
     for (int i = 0; i < NUM_LOG_SOURCES; i++)
         qd_log_source_free_lh(i);
     while (DEQ_HEAD(entries))