please see bug 2312 #2
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Both of these were using a common linked-list structure that could be reorderd while being traversed. Now they're copied out to a temporary array at processing time and all the links are broken. Also changed here is what it does when needing to deal with pending_close (e.g. don't directly close stuff), but that's a necessary casualty.
Instead of defaulting to "SERVER_ERROR unhandled storage type.", added more case clauses to emit more detailed ascii-protocol CLIENT/SERVER_ERROR strings.
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Fix race identified by ThreadSanitizer:
WARNING: ThreadSanitizer: data race (pid=6808)
Write of size 4 at 0x7ff2762e50b0 by thread T7:
#0 mock_get_current_time /home/vagrant/couchbase-server/memcached/programs/engine_testapp/mock_server.c:142 (exe+0x0000000ad73a)
#1 ExecutorThread::run() /home/vagrant/couchbase-server/ep-engine/src/executorthread.cc:101 (ep.so+0x000000215f3d)
#2 launch_executor_thread(void*) /home/vagrant/couchbase-server/ep-engine/src/executorthread.cc:34 (ep.so+0x00000021560a)
#3 platform_thread_wrap /home/vagrant/couchbase-server/platform/src/cb_pthreads.c:19 (libplatform.so.0.1.0+0x0000000033f4)
Previous write of size 4 at 0x7ff2762e50b0 by thread T6:
#0 mock_get_current_time /home/vagrant/couchbase-server/memcached/programs/engine_testapp/mock_server.c:142 (exe+0x0000000ad73a)
#1 ExecutorThread::run() /home/vagrant/couchbase-server/ep-engine/src/executorthread.cc:101 (ep.so+0x000000215f3d)
#2 launch_executor_thread(void*) /home/vagrant/couchbase-server/ep-engine/src/executorthread.cc:34 (ep.so+0x00000021560a)
#3 platform_thread_wrap /home/vagrant/couchbase-server/platform/src/cb_pthreads.c:19 (libplatform.so.0.1.0+0x0000000033f4)
Change-Id: I392fd79245e690589f498690efe483ea856ef8d5
Reviewed-on: http://review.couchbase.org/43321
Tested-by: buildbot <[email protected]>
Reviewed-by: Michael Wiederhold <[email protected]>
Reviewed-by: Trond Norbye <[email protected]>
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Mar 17, 2016
Identified by ThreadSanitizer:
WARNING: ThreadSanitizer: data race (pid=34137)
Write of size 4 at 0x7fa0ab35b288 by main thread:
#0 mc_time_clock_tick() /home/daver/repos/couchbase/server/memcached/daemon/mc_time.cc:171 (memcached+0x0000000f9df3)
#1 mc_time_clock_event_handler(int, short, void*) /home/daver/repos/couchbase/server/memcached/daemon/mc_time.cc:158 (memcached+0x0000000fa08f)
#2 event_process_active_single_queue /home/couchbase/jenkins/workspace/cbdeps-build/label/ubuntu14.04/release/sherlock/deps/packages/build/libevent/libevent-prefix/src/libevent/event.c:1368 (libevent_core-2.0.so.5+0x00000000b7cb)
#3 __libc_start_main /build/buildd/eglibc-2.19/csu/libc-start.c:287 (libc.so.6+0x000000021ec4)
Previous read of size 4 at 0x7fa0ab35b288 by thread T12 (mutexes: write M45839, write M45891):
#0 mc_time_get_current_time /home/daver/repos/couchbase/server/memcached/daemon/mc_time.cc:94 (memcached+0x0000000fa0b6)
#1 do_item_update /home/daver/repos/couchbase/server/memcached/engines/default_engine/items.c:358 (default_engine.so+0x000000008109)
#2 item_get /home/daver/repos/couchbase/server/memcached/engines/default_engine/items.c:821 (default_engine.so+0x000000007deb)
#3 default_get /home/daver/repos/couchbase/server/memcached/engines/default_engine/default_engine.c:335 (default_engine.so+0x000000003ef5)
#4 EWB_Engine::get(engine_interface*, void const*, void**, void const*, int, unsigned short) /home/daver/repos/couchbase/server/memcached/engines/ewouldblock_engine/ewouldblock_engine.cc:247 (ewouldblock_engine.so+0x000000004fc1)
#5 bucket_get /home/daver/repos/couchbase/server/memcached/daemon/memcached.cc:123 (memcached+0x0000000e096a)
#6 process_bin_packet(conn*) /home/daver/repos/couchbase/server/memcached/daemon/memcached.cc:5051 (memcached+0x0000000d2100)
memcached#7 run_event_loop /home/daver/repos/couchbase/server/memcached/daemon/connections.cc:174 (memcached+0x0000000c70c3)
memcached#8 thread_libevent_process(int, short, void*) /home/daver/repos/couchbase/server/memcached/daemon/thread.cc:374 (memcached+0x0000000f8fc0)
memcached#9 event_persist_closure /home/couchbase/jenkins/workspace/cbdeps-build/label/ubuntu14.04/release/sherlock/deps/packages/build/libevent/libevent-prefix/src/libevent/event.c:1319 (libevent_core-2.0.so.5+0x00000000b6c7)
memcached#10 platform_thread_wrap /home/daver/repos/couchbase/server/platform/src/cb_pthreads.c:23 (libplatform.so.0.1.0+0x000000003730)
Change-Id: I9d73a6f5553d88beb1bcc2526763d892fe1b990f
Reviewed-on: http://review.couchbase.org/52484
Tested-by: buildbot <[email protected]>
Reviewed-by: Trond Norbye <[email protected]>
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Mar 17, 2016
As identified by ThreadSanitizer:
WARNING: ThreadSanitizer: data race (pid=3766)
Write of size 4 at 0x7fe54b854b48 by main thread:
#0 shutdown_server() /home/daver/repos/couchbase/server/memcached/daemon/memcached.cc:7530 (memcached+0x0000000dcca6)
#1 event_signal_closure /home/couchbase/jenkins/workspace/cbdeps-build/label/ubuntu14.04/release/sherlock/deps/packages/build/libevent/libevent-prefix/src/libevent/event.c:1064 (libevent_core-2.0.so.5+0x00000000b9c8)
#2 __libc_start_main /build/buildd/eglibc-2.19/csu/libc-start.c:287 (libc.so.6+0x000000021ec4)
Previous read of size 4 at 0x7fe54b854b48 by thread T3:
#0 event_handler /home/daver/repos/couchbase/server/memcached/daemon/memcached.cc:6884 (memcached+0x0000000d79c6)
#1 event_persist_closure /home/couchbase/jenkins/workspace/cbdeps-build/label/ubuntu14.04/release/sherlock/deps/packages/build/libevent/libevent-prefix/src/libevent/event.c:1319 (libevent_core-2.0.so.5+0x00000000b6c7)
#2 platform_thread_wrap /home/daver/repos/couchbase/server/platform/src/cb_pthreads.c:23 (libplatform.so.0.1.0+0x000000003730)
Change-Id: I36c97dda9379718c2c1bb7f99698413616e59cbf
Reviewed-on: http://review.couchbase.org/52485
Tested-by: buildbot <[email protected]>
Reviewed-by: Trond Norbye <[email protected]>
trondn
pushed a commit
that referenced
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Mar 17, 2016
As identified by ThreadSanitizer:
WARNING: ThreadSanitizer: data race (pid=950)
Write of size 8 at 0x7d100002db60 by thread T17 (mutexes: write M45854):
#0 operator delete(void*) <null>:0 (memcached+0x00000005a6bb)
#1 __gnu_cxx::new_allocator<...>::deallocate(...) /usr/bin/../lib/gcc/x86_64-linux-gnu/4.9/../../../../include/c++/4.9/ext/new_allocator.h:110 (ewouldblock_engine.so+0x000000007677)
#2 std::_Rb_tree<>::erase(...) /usr/bin/../lib/gcc/x86_64-linux-gnu/4.9/../../../../include/c++/4.9/bits/stl_tree.h:890 (ewouldblock_engine.so+0x000000005890)
#3 bucket_unknown_command /home/daver/repos/couchbase/server/memcached/daemon/memcached.cc:130 (memcached+0x0000000e8cd0)
#4 process_bin_unknown_packet(conn*) /home/daver/repos/couchbase/server/memcached/daemon/memcached.cc:1877 (memcached+0x0000000d2223)
#5 run_event_loop /home/daver/repos/couchbase/server/memcached/daemon/connections.cc:174 (memcached+0x0000000c70c3)
#6 event_handler /home/daver/repos/couchbase/server/memcached/daemon/memcached.cc:6908 (memcached+0x0000000d7b24)
memcached#7 event_persist_closure /home/couchbase/jenkins/workspace/cbdeps-build/label/ubuntu14.04/release/sherlock/deps/packages/build/libevent/libevent-prefix/src/libevent/event.c:1319 (libevent_core-2.0.so.5+0x00000000b6c7)
memcached#8 platform_thread_wrap /home/daver/repos/couchbase/server/platform/src/cb_pthreads.c:23 (libplatform.so.0.1.0+0x000000003730)
Previous read of size 8 at 0x7d100002db60 by thread T16 (mutexes: write M45851, write M45962):
#0 std::less<void const*>::operator()(void const* const&, void const* const&) const /usr/bin/../lib/gcc/x86_64-linux-gnu/4.9/../../../../include/c++/4.9/bits/stl_function.h:371 (ewouldblock_engine.so+0x000000006ac8)
#1 EWB_Engine::should_inject_error(...) /home/daver/repos/couchbase/server/memcached/engines/ewouldblock_engine/ewouldblock_engine.cc:110 (ewouldblock_engine.so+0x000000006c31)
#2 EWB_Engine::allocate(...) /home/daver/repos/couchbase/server/memcached/engines/ewouldblock_engine/ewouldblock_engine.cc:211 (ewouldblock_engine.so+0x000000004d33)
#3 add_set_replace_executor(conn*, void*, ENGINE_STORE_OPERATION) /home/daver/repos/couchbase/server/memcached/daemon/memcached.cc:3940 (memcached+0x0000000e7b40)
#4 setq_executor(conn*, void*) /home/daver/repos/couchbase/server/memcached/daemon/memcached.cc:4079 (memcached+0x0000000e0496)
#5 process_bin_packet(conn*) /home/daver/repos/couchbase/server/memcached/daemon/memcached.cc:5051 (memcached+0x0000000d2100)
#6 run_event_loop /home/daver/repos/couchbase/server/memcached/daemon/connections.cc:174 (memcached+0x0000000c70c3)
memcached#7 event_handler /home/daver/repos/couchbase/server/memcached/daemon/memcached.cc:6908 (memcached+0x0000000d7b24)
memcached#8 event_persist_closure /home/couchbase/jenkins/workspace/cbdeps-build/label/ubuntu14.04/release/sherlock/deps/packages/build/libevent/libevent-prefix/src/libevent/event.c:1319 (libevent_core-2.0.so.5+0x00000000b6c7)
memcached#9 platform_thread_wrap /home/daver/repos/couchbase/server/platform/src/cb_pthreads.c:23 (libplatform.so.0.1.0+0x000000003730)
Change-Id: Ia558b1947f2c913d6fa7943de0e85ba975a0c2b1
Reviewed-on: http://review.couchbase.org/52486
Tested-by: buildbot <[email protected]>
Reviewed-by: Trond Norbye <[email protected]>
trondn
pushed a commit
that referenced
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Mar 17, 2016
As reported by ThreadSanitizer:
WARNING: ThreadSanitizer: data race (pid=34992)
Read of size 4 at 0x7f98b38b5bf4 by main thread:
#0 run_event_loop /home/daver/repos/couchbase/server/memcached/daemon/connections.cc:170 (memcached+0x0000000c7049)
#1 event_handler /home/daver/repos/couchbase/server/memcached/daemon/memcached.cc:6912 (memcached+0x0000000d7b34)
#2 event_persist_closure /home/couchbase/jenkins/workspace/cbdeps-build/label/ubuntu14.04/release/sherlock/deps/packages/build/libevent/libevent-prefix/src/libevent/event.c:1319 (libevent_core-2.0.so.5+0x00000000b6c7)
#3 __libc_start_main /build/buildd/eglibc-2.19/csu/libc-start.c:287 (libc.so.6+0x000000021ec4)
Previous write of size 4 at 0x7f98b38b5bf4 by thread T19 (mutexes: write M45860):
#0 verbosity_executor(conn*, void*) /home/daver/repos/couchbase/server/memcached/daemon/memcached.cc:3600 (memcached+0x0000000df219)
#1 process_bin_packet(conn*) /home/daver/repos/couchbase/server/memcached/daemon/memcached.cc:5053 (memcached+0x0000000d2100)
#2 run_event_loop /home/daver/repos/couchbase/server/memcached/daemon/connections.cc:174 (memcached+0x0000000c70c3)
#3 event_handler /home/daver/repos/couchbase/server/memcached/daemon/memcached.cc:6912 (memcached+0x0000000d7b34)
#4 event_persist_closure /home/couchbase/jenkins/workspace/cbdeps-build/label/ubuntu14.04/release/sherlock/deps/packages/build/libevent/libevent-prefix/src/libevent/event.c:1319 (libevent_core-2.0.so.5+0x00000000b6c7)
#5 platform_thread_wrap /home/daver/repos/couchbase/server/platform/src/cb_pthreads.c:23 (libplatform.so.0.1.0+0x000000003730)
Change-Id: I2ae83312a532c67b2e3915e0c604e4e60558a8a7
Reviewed-on: http://review.couchbase.org/52487
Tested-by: buildbot <[email protected]>
Reviewed-by: Trond Norbye <[email protected]>
trondn
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that referenced
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Mar 17, 2016
Fix warning from ThreadSanitizer - appears to have been triggered by
some recent refactoring:
WARNING: ThreadSanitizer: data race (pid=176554)
Read of size 8 at 0x7f65cd0df200 by main thread:
#0 main memcached/auditd/tests/testauditd.cc:258 (memcached_auditd_tests+0x0000000c3437)
Previous write of size 8 at 0x7f65cd0df200 by thread T1 (mutexes: write M155):
#0 audit_processed_listener() memcached/auditd/tests/testauditd.cc:142 (memcached_auditd_tests+0x0000000c2526)
#1 consume_events(void*) memcached/auditd/src/auditd.cc:81 (libauditd.so.0.1.0+0x0000000109a1)
#2 platform_thread_wrap (libplatform.so.0.1.0+0x000000003da1)
Change-Id: I90c21b62f999953015eaa25f5957c1a0db280e99
Reviewed-on: http://review.couchbase.org/54888
Reviewed-by: Trond Norbye <[email protected]>
Tested-by: buildbot <[email protected]>
trondn
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Mar 17, 2016
Add identified by ThreadSanitizer. mock_connstruct::references is
accessed concurrently from two threads; update to use std::atomic.
Details:
WARNING: ThreadSanitizer: data race (pid=32054)
Write of size 4 at 0x7d280000eff0 by main thread:
#0 mock_cookie_reserve() /memcached/programs/engine_testapp/mock_server.cc:129:5 (engine_testapp+0x0000004c77c3)
#1 EventuallyPersistentEngine::reserveCookie() /ep-engine/src/ep_engine.cc:2016:28 (ep.so+0x0000000a2f05)
#2 EventuallyPersistentEngine::createTapQueue() /ep-engine/src/ep_engine.cc:2574 (ep.so+0x0000000a2f05)
#3 EvpGetTapIterator() /ep-engine/src/ep_engine.cc:1463:17 (ep.so+0x00000009f943)
#4 mock_get_tap_iterator() /memcached/programs/engine_testapp/engine_testapp.cc:467:20 (engine_testapp+0x0000004c59ce)
#5 test_tap_ack_stream() /ep-engine/tests/ep_testsuite.cc:7341:20 (ep_testsuite.so+0x00000003edf0)
#6 execute_test() /memcached/programs/engine_testapp/engine_testapp.cc:1090:19 (engine_testapp+0x0000004c4142)
memcached#7 main /memcached/programs/engine_testapp/engine_testapp.cc:1439 (engine_testapp+0x0000004c4142)
Previous write of size 4 at 0x7d280000eff0 by thread T10 (mutexes: write M2181):
#0 mock_cookie_release() /memcached/programs/engine_testapp/mock_server.cc:136:5 (engine_testapp+0x0000004c7801)
#1 EventuallyPersistentEngine::releaseCookie() /ep-engine/src/ep_engine.cc:2025:28 (ep.so+0x0000000a1142)
#2 ConnHandler::releaseReference() /ep-engine/src/tapconnection.cc:311:9 (ep.so+0x0000000fc5d2)
#3 TapConnMap::manageConnections() /ep-engine/src/connmap.cc:532:10 (ep.so+0x00000003e972)
#4 ConnManager::run() /ep-engine/src/connmap.cc:150:9 (ep.so+0x00000004a60e)
#5 ExecutorThread::run() /ep-engine/src/executorthread.cc:115:26 (ep.so+0x0000000d8a9e)
#6 launch_executor_thread() /ep-engine/src/executorthread.cc:33:9 (ep.so+0x0000000d8615)
memcached#7 platform_thread_wrap /platform/src/cb_pthreads.c:23:5 (libplatform.so.0.1.0+0x000000003c31)
Change-Id: Ib1861cf9b66e31b5f50e6b114119da72d54cde10
Reviewed-on: http://review.couchbase.org/55866
Reviewed-by: abhinav dangeti <[email protected]>
Tested-by: buildbot <[email protected]>
trondn
pushed a commit
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Mar 17, 2016
…okie
WARNING: ThreadSanitizer: data race (pid=39351)
Write of size 8 at 0x7d2800009f60 by thread T18 (mutexes: write M1477):
#0 free <null> (engine_testapp+0x00000045ca0b)
#1 mock_cookie_release(void const*) /home/couchbase/jenkins/workspace/ep-engine-threadsanitizer-master/memcached/programs/engine_testapp/mock_server.cc:138 (engine_testapp+0x0000004c7850)
#2 EventuallyPersistentEngine::releaseCookie(void const*) /home/couchbase/jenkins/workspace/ep-engine-threadsanitizer-master/ep-engine/src/ep_engine.cc:2031 (ep.so+0x0000000add62)
#3 ConnHandler::releaseReference(bool) /home/couchbase/jenkins/workspace/ep-engine-threadsanitizer-master/ep-engine/src/tapconnection.cc:311 (ep.so+0x0000001106d2)
#4 DcpConnMap::manageConnections() /home/couchbase/jenkins/workspace/ep-engine-threadsanitizer-master/ep-engine/src/connmap.cc:1189 (ep.so+0x0000000461df)
#5 ConnManager::run() /home/couchbase/jenkins/workspace/ep-engine-threadsanitizer-master/ep-engine/src/connmap.cc:150 (ep.so+0x00000004c5ae)
#6 ExecutorThread::run() /home/couchbase/jenkins/workspace/ep-engine-threadsanitizer-master/ep-engine/src/executorthread.cc:115 (ep.so+0x0000000eaabd)
memcached#7 launch_executor_thread(void*) /home/couchbase/jenkins/workspace/ep-engine-threadsanitizer-master/ep-engine/src/executorthread.cc:33 (ep.so+0x0000000ea685)
memcached#8 platform_thread_wrap /home/couchbase/.ccache/tmp/cb_pthread.tmp.334a1e8a4a71.179339.i (libplatform.so.0.1.0+0x0000000041c1)
Previous read of size 8 at 0x7d2800009f60 by thread T20:
#0 mock_get_engine_specific(void const*) /home/couchbase/jenkins/workspace/ep-engine-threadsanitizer-master/memcached/programs/engine_testapp/mock_server.cc:82 (engine_testapp+0x0000004c75a0)
#1 EventuallyPersistentEngine::handleDisconnect(void const*) /home/couchbase/jenkins/workspace/ep-engine-threadsanitizer-master/ep-engine/src/ep_engine.h:584 (ep.so+0x0000000c956d)
#2 EvpHandleDisconnect(void const*, ENGINE_EVENT_TYPE, void const*, void const*) /home/couchbase/jenkins/workspace/ep-engine-threadsanitizer-master/ep-engine/src/ep_engine.cc:1786 (ep.so+0x0000000aeb46)
#3 destroy_mock_cookie /home/couchbase/jenkins/workspace/ep-engine-threadsanitizer-master/memcached/programs/engine_testapp/mock_server.cc:319 (engine_testapp+0x0000004c7f83)
#4 perf_dcp_client(Handle_args*) /home/couchbase/jenkins/workspace/ep-engine-threadsanitizer-master/ep-engine/tests/ep_perfsuite.cc:653 (ep_perfsuite.so+0x00000000fcdc)
#5 platform_thread_wrap /home/couchbase/.ccache/tmp/cb_pthread.tmp.334a1e8a4a71.179339.i (libplatform.so.0.1.0+0x0000000041c1)
WARNING: ThreadSanitizer: data race (pid=39351)
Write of size 8 at 0x7d2800009ff0 by thread T18 (mutexes: write M1477):
#0 free <null> (engine_testapp+0x00000045ca0b)
#1 mock_cookie_release(void const*) /home/couchbase/jenkins/workspace/ep-engine-threadsanitizer-master/memcached/programs/engine_testapp/mock_server.cc:138 (engine_testapp+0x0000004c7850)
#2 EventuallyPersistentEngine::releaseCookie(void const*) /home/couchbase/jenkins/workspace/ep-engine-threadsanitizer-master/ep-engine/src/ep_engine.cc:2031 (ep.so+0x0000000add62)
#3 ConnHandler::releaseReference(bool) /home/couchbase/jenkins/workspace/ep-engine-threadsanitizer-master/ep-engine/src/tapconnection.cc:311 (ep.so+0x0000001106d2)
#4 DcpConnMap::manageConnections() /home/couchbase/jenkins/workspace/ep-engine-threadsanitizer-master/ep-engine/src/connmap.cc:1189 (ep.so+0x0000000461df)
#5 ConnManager::run() /home/couchbase/jenkins/workspace/ep-engine-threadsanitizer-master/ep-engine/src/connmap.cc:150 (ep.so+0x00000004c5ae)
#6 ExecutorThread::run() /home/couchbase/jenkins/workspace/ep-engine-threadsanitizer-master/ep-engine/src/executorthread.cc:115 (ep.so+0x0000000eaabd)
memcached#7 launch_executor_thread(void*) /home/couchbase/jenkins/workspace/ep-engine-threadsanitizer-master/ep-engine/src/executorthread.cc:33 (ep.so+0x0000000ea685)
memcached#8 platform_thread_wrap /home/couchbase/.ccache/tmp/cb_pthread.tmp.334a1e8a4a71.179339.i (libplatform.so.0.1.0+0x0000000041c1)
Previous atomic read of size 4 at 0x7d2800009ff0 by thread T20:
#0 __tsan_atomic32_load <null> (engine_testapp+0x0000004a51b4)
#1 destroy_mock_cookie /home/couchbase/jenkins/workspace/ep-engine-threadsanitizer-master/memcached/programs/engine_testapp/mock_server.cc:318 (engine_testapp+0x0000004c7fa0)
#2 perf_dcp_client(Handle_args*) /home/couchbase/jenkins/workspace/ep-engine-threadsanitizer-master/ep-engine/tests/ep_perfsuite.cc:653 (ep_perfsuite.so+0x00000000fcdc)
#3 platform_thread_wrap /home/couchbase/.ccache/tmp/cb_pthread.tmp.334a1e8a4a71.179339.i (libplatform.so.0.1.0+0x0000000041c1)
Change-Id: If36aa90a181e5cd49aeede04065b78bb1fe17dc1
Reviewed-on: http://review.couchbase.org/56100
Tested-by: buildbot <[email protected]>
Reviewed-by: Dave Rigby <[email protected]>
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