executor: fix data race

ThreadSanitizer says:

WARNING: ThreadSanitizer: data race (pid=3)
  Atomic read of size 4 at 0x56360e562f08 by main thread:
    #0 __tsan_atomic32_load <null> (libtsan.so.0+0x64249)
    #1 event_isset executor/common_linux.h:51 (syz-executor.0+0x2cf1f)
    #2 handle_completion executor/executor.cc:886 (syz-executor.0+0x2cf1f)
    #3 execute_one executor/executor.cc:732 (syz-executor.0+0x2da3b)
    #4 loop executor/common.h:581 (syz-executor.0+0x2f1aa)
    #5 do_sandbox_none executor/common_linux.h:2694 (syz-executor.0+0x189d6)
    #6 main executor/executor.cc:407 (syz-executor.0+0x189d6)

  Previous write of size 4 at 0x56360e562f08 by thread T1:
    #0 event_reset executor/common_linux.h:32 (syz-executor.0+0x1f5af)
    #1 worker_thread executor/executor.cc:1048 (syz-executor.0+0x1f5af)
    #2 <null> <null> (libtsan.so.0+0x2b0b6)

  Location is global 'threads' of size 2560 at 0x56360e562f00 (syz-executor.0+0x00000008bf08)

  Thread T1 (tid=6, running) created by main thread at:
    #0 pthread_create <null> (libtsan.so.0+0x2d55b)
    #1 thread_start executor/common.h:256 (syz-executor.0+0x2d707)
    #2 thread_create executor/executor.cc:1037 (syz-executor.0+0x2d707)
    #3 schedule_call executor/executor.cc:811 (syz-executor.0+0x2d707)
    #4 execute_one executor/executor.cc:719 (syz-executor.0+0x2d707)
    #5 loop executor/common.h:581 (syz-executor.0+0x2f1aa)
    #6 do_sandbox_none executor/common_linux.h:2694 (syz-executor.0+0x189d6)
    #7 main executor/executor.cc:407 (syz-executor.0+0x189d6)

0 files changed, 0 insertions, 0 deletions