between two server instances at server shutdown/startup.
This conflict on advisory locks appears to be the result of a bug
in the operating system; these locks should be released when the
files are closed, but somehow that does not always happen
immediately in Linux.  (Bug #9381)


innobase/include/os0file.h:
  Add OS_FILE_OPEN_RETRY for os_file_create()ing ibdata1
innobase/os/os0file.c:
  os_file_lock(): Do not close the file on failure, but let the
  callers do that.
  os_file_create(): If create_mode==OS_FILE_OPEN_RETRY and
  os_file_lock() fails, keep retrying for 100 seconds.
innobase/srv/srv0start.c:
  open_or_create_data_files(): Open the first data file with
  OS_FILE_OPEN_RETRY, to resolve a conflict with a shutting-down
  instance of the MySQL server.