• Waiman Long's avatar
    blk-iocost: Fix error on iocost_ioc_vrate_adj · d6c8e949
    Waiman Long authored
    Systemtap 4.2 is unable to correctly interpret the "u32 (*missed_ppm)[2]"
    argument of the iocost_ioc_vrate_adj trace entry defined in
    include/trace/events/iocost.h leading to the following error:
    
      /tmp/stapAcz0G0/stap_c89c58b83cea1724e26395efa9ed4939_6321_aux_6.c:78:8:
      error: expected ‘;’, ‘,’ or ‘)’ before ‘*’ token
       , u32[]* __tracepoint_arg_missed_ppm
    
    That argument type is indeed rather complex and hard to read. Looking
    at block/blk-iocost.c. It is just a 2-entry u32 array. By simplifying
    the argument to a simple "u32 *missed_ppm" and adjusting the trace
    entry accordingly, the compilation error was gone.
    
    Fixes: 7caa4715 ("blkcg: implement blk-iocost")
    Acked-by: default avatarSteven Rostedt (VMware) <rostedt@goodmis.org>
    Acked-by: default avatarTejun Heo <tj@kernel.org>
    Signed-off-by: default avatarWaiman Long <longman@redhat.com>
    Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
    d6c8e949
iocost.h 4.93 KB