Address data race in ep_test_apis/testsuite

WARNING: ThreadSanitizer: data race (pid=18824)

  Write of size 4 at 0x7fcc31350244 by thread T12 (mutexes: write M44413):
    #0 add_response /home/abhinav/couchbase/ep-engine/tests/ep_test_apis.cc:75 (ep_testsuite.so+0x0000000acbcc)
    couchbase#1 sendResponse(bool (*)(void const*, unsigned short, void const*, unsigned char, void const*, unsigned int, unsigned char, unsigned short, unsigned long, void const*), void const*, unsigned short, void const*, unsigned char, void const*, unsigned int, unsigned char, unsigned short, unsigned long, void const*) /home/abhinav/couchbase/ep-engine/src/ep_engine.cc:92 (ep.so+0x0000000d004c)
    couchbase#2 processUnknownCommand(EventuallyPersistentEngine*, void const*, protocol_binary_request_header*, bool (*)(void const*, unsigned short, void const*, unsigned char, void const*, unsigned int, unsigned char, unsigned short, unsigned long, void const*)) /home/abhinav/couchbase/ep-engine/src/ep_engine.cc:1266 (ep.so+0x0000000d603c)
    couchbase#3 EvpUnknownCommand(engine_interface*, void const*, protocol_binary_request_header*, bool (*)(void const*, unsigned short, void const*, unsigned char, void const*, unsigned int, unsigned char, unsigned short, unsigned long, void const*)) /home/abhinav/couchbase/ep-engine/src/ep_engine.cc:1387 (ep.so+0x0000000b3f58)
    couchbase#4 mock_unknown_command(engine_interface*, void const*, protocol_binary_request_header*, bool (*)(void const*, unsigned short, void const*, unsigned char, void const*, unsigned int, unsigned char, unsigned short, unsigned long, void const*)) /home/abhinav/couchbase/memcached/programs/engine_testapp/engine_testapp.cc:380 (engine_testapp+0x0000000bab29)
    couchbase#5 del_with_meta(engine_interface*, engine_interface_v1*, char const*, unsigned long, unsigned int, ItemMetaData*, unsigned long, bool, bool, long, unsigned char, void const*) /home/abhinav/couchbase/ep-engine/tests/ep_test_apis.cc:360 (ep_testsuite.so+0x0000000ae69f)
    #6 multi_del_with_meta(void*) /home/abhinav/couchbase/ep-engine/tests/ep_testsuite.cc:13299 (ep_testsuite.so+0x00000009572e)
    #7 platform_thread_wrap /home/abhinav/couchbase/platform/src/cb_pthreads.c:23 (libplatform.so.0.1.0+0x000000003d31)

  Previous write of size 4 at 0x7fcc31350244 by thread T11 (mutexes: write M1638603450185076640):
    #0 add_response /home/abhinav/couchbase/ep-engine/tests/ep_test_apis.cc:75 (ep_testsuite.so+0x0000000acbcc)
    couchbase#1 sendResponse(bool (*)(void const*, unsigned short, void const*, unsigned char, void const*, unsigned int, unsigned char, unsigned short, unsigned long, void const*), void const*, unsigned short, void const*, unsigned char, void const*, unsigned int, unsigned char, unsigned short, unsigned long, void const*) /home/abhinav/couchbase/ep-engine/src/ep_engine.cc:92 (ep.so+0x0000000ced72)
    couchbase#2 processUnknownCommand(EventuallyPersistentEngine*, void const*, protocol_binary_request_header*, bool (*)(void const*, unsigned short, void const*, unsigned char, void const*, unsigned int, unsigned char, unsigned short, unsigned long, void const*)) /home/abhinav/couchbase/ep-engine/src/ep_engine.cc:1258 (ep.so+0x0000000d5718)
    couchbase#3 EvpUnknownCommand(engine_interface*, void const*, protocol_binary_request_header*, bool (*)(void const*, unsigned short, void const*, unsigned char, void const*, unsigned int, unsigned char, unsigned short, unsigned long, void const*)) /home/abhinav/couchbase/ep-engine/src/ep_engine.cc:1387 (ep.so+0x0000000b3f58)
    couchbase#4 mock_unknown_command(engine_interface*, void const*, protocol_binary_request_header*, bool (*)(void const*, unsigned short, void const*, unsigned char, void const*, unsigned int, unsigned char, unsigned short, unsigned long, void const*)) /home/abhinav/couchbase/memcached/programs/engine_testapp/engine_testapp.cc:380 (engine_testapp+0x0000000bab29)
    couchbase#5 set_with_meta(engine_interface*, engine_interface_v1*, char const*, unsigned long, char const*, unsigned long, unsigned int, ItemMetaData*, unsigned long, bool, unsigned char, bool, long, unsigned char, void const*) /home/abhinav/couchbase/ep-engine/tests/ep_test_apis.cc:702 (ep_testsuite.so+0x0000000b24db)
    #6 multi_set_with_meta(void*) /home/abhinav/couchbase/ep-engine/tests/ep_testsuite.cc:13279 (ep_testsuite.so+0x000000094e33)
    #7 platform_thread_wrap /home/abhinav/couchbase/platform/src/cb_pthreads.c:23 (libplatform.so.0.1.0+0x000000003d31)

Change-Id: Ic53d401fb674dbe161aa73381e2c08c5995f262a
Reviewed-on: http://review.couchbase.org/55849
Reviewed-by: Chiyoung Seo <chiyoung@couchbase.com>
Tested-by: buildbot <build@couchbase.com>

Author: abhinavdangeti

tests/ep_test_apis.cc

@@ -31,17 +31,17 @@
 
 std::map<std::string, std::string> vals;
 bool dump_stats = false;
-protocol_binary_response_status last_status =
-    static_cast<protocol_binary_response_status>(0);
+AtomicValue<protocol_binary_response_status> last_status(
+    static_cast<protocol_binary_response_status>(0));
 std::string last_key;
 std::string last_body;
-bool last_deleted_flag = false;
-uint8_t last_conflict_resolution_mode = static_cast<uint8_t>(-1);
-uint64_t last_cas = 0;
-uint8_t last_datatype = 0x00;
+bool last_deleted_flag(false);
+uint8_t last_conflict_resolution_mode(static_cast<uint8_t>(-1));
+AtomicValue<uint64_t> last_cas(0);
+AtomicValue<uint8_t> last_datatype(0x00);
 ItemMetaData last_meta;
-uint64_t last_uuid = 0;
-uint64_t last_seqno = 0;
+AtomicValue<uint64_t> last_uuid(0);
+AtomicValue<uint64_t> last_seqno(0);
 
 extern "C" bool add_response_get_meta(const void *key, uint16_t keylen,
                                       const void *ext, uint8_t extlen,
@@ -72,11 +72,11 @@ bool add_response(const void *key, uint16_t keylen, const void *ext,
     (void)ext;
     (void)extlen;
     (void)cookie;
-    last_status = static_cast<protocol_binary_response_status>(status);
+    last_status.store(static_cast<protocol_binary_response_status>(status));
     last_body.assign(static_cast<const char*>(body), bodylen);
     last_key.assign(static_cast<const char*>(key), keylen);
-    last_cas = cas;
-    last_datatype = datatype;
+    last_cas.store(cas);
+    last_datatype.store(datatype);
     return true;
 }
 
@@ -115,8 +115,8 @@ bool add_response_set_del_meta(const void *key, uint16_t keylen, const void *ext
         uint64_t seqno;
         memcpy(&vb_uuid, ext_bytes, 8);
         memcpy(&seqno, ext_bytes + 8, 8);
-        last_uuid = ntohll(vb_uuid);
-        last_seqno = ntohll(seqno);
+        last_uuid.store(ntohll(vb_uuid));
+        last_seqno.store(ntohll(seqno));
     }
 
     return add_response(key, keylen, ext, extlen, body, bodylen, datatype,
@@ -959,7 +959,7 @@ bool verify_vbucket_state(ENGINE_HANDLE *h, ENGINE_HANDLE_V1 *h1, uint16_t vb,
     if (last_status != PROTOCOL_BINARY_RESPONSE_SUCCESS) {
         if (!mute) {
             fprintf(stderr, "Last protocol status was %d (%s)\n",
-                    last_status,
+                    last_status.load(),
                     last_body.size() > 0 ? last_body.c_str() : "unknown");
         }
         return false;

tests/ep_test_apis.h

@@ -55,16 +55,16 @@ ENGINE_ERROR_CODE vb_map_response(const void *cookie, const void *map,
 }
 #endif
 
-extern protocol_binary_response_status last_status;
+extern AtomicValue<protocol_binary_response_status> last_status;
 extern std::string last_key;
 extern std::string last_body;
 extern bool dump_stats;
 extern std::map<std::string, std::string> vals;
 extern uint32_t last_bodylen;
-extern uint64_t last_cas;
-extern uint8_t last_datatype;
-extern uint64_t last_uuid;
-extern uint64_t last_seqno;
+extern AtomicValue<uint64_t> last_cas;
+extern AtomicValue<uint8_t> last_datatype;
+extern AtomicValue<uint64_t> last_uuid;
+extern AtomicValue<uint64_t> last_seqno;
 extern bool last_deleted_flag;
 extern uint8_t last_conflict_resolution_mode;
 extern ItemMetaData last_meta;

tests/ep_testsuite.cc

@@ -226,7 +226,7 @@ static enum test_result test_getl(ENGINE_HANDLE *h, ENGINE_HANDLE_V1 *h1) {
     getl(h, h1, key, vbucketId, expiration);
     check(last_status == PROTOCOL_BINARY_RESPONSE_SUCCESS,
           "Aquire lock should have succeeded");
-    auto locked_cas = last_cas;
+    auto locked_cas = last_cas.load();
     /* append should fail */
     check(storeCasVb11(h, h1, NULL, OPERATION_APPEND, key,
                        binaryData2, sizeof(binaryData2) - 1, 82758, &i, 0, 0)