• S
    efi_pstore: Add a sequence counter to a variable name · 755d4fe4
    Seiji Aguchi 提交于
    [Issue]
    
    Currently, a variable name, which identifies each entry, consists of type, id and ctime.
    But if multiple events happens in a short time, a second/third event may fail to log because
    efi_pstore can't distinguish each event with current variable name.
    
    [Solution]
    
    A reasonable way to identify all events precisely is introducing a sequence counter to
    the variable name.
    
    The sequence counter has already supported in a pstore layer with "oopscount".
    So, this patch adds it to a variable name.
    Also, it is passed to read/erase callbacks of platform drivers in accordance with
    the modification of the variable name.
    
      <before applying this patch>
     a variable name of first event: dump-type0-1-12345678
     a variable name of second event: dump-type0-1-12345678
    
      type:0
      id:1
      ctime:12345678
    
     If multiple events happen in a short time, efi_pstore can't distinguish them because
     variable names are same among them.
    
      <after applying this patch>
    
     it can be distinguishable by adding a sequence counter as follows.
    
     a variable name of first event: dump-type0-1-1-12345678
     a variable name of Second event: dump-type0-1-2-12345678
    
      type:0
      id:1
      sequence counter: 1(first event), 2(second event)
      ctime:12345678
    
    In case of a write callback executed in pstore_console_write(), "0" is added to
    an argument of the write callback because it just logs all kernel messages and
    doesn't need to care about multiple events.
    Signed-off-by: NSeiji Aguchi <seiji.aguchi@hds.com>
    Acked-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
    Acked-by: NMike Waychison <mikew@google.com>
    Signed-off-by: NTony Luck <tony.luck@intel.com>
    755d4fe4
ram.c 13.7 KB