• Steven Rostedt (Red Hat)'s avatar
    tracing: Init current_trace to nop_trace and remove NULL checks · d840f718
    Steven Rostedt (Red Hat) authored
    On early boot up, when the ftrace ring buffer is initialized, the
    static variable current_trace is initialized to &nop_trace.
    Before this initialization, current_trace is NULL and will never
    become NULL again. It is always reassigned to a ftrace tracer.
    
    Several places check if current_trace is NULL before it uses
    it, and this check is frivolous, because at the point in time
    when the checks are made the only way current_trace could be
    NULL is if ftrace failed its allocations at boot up, and the
    paths to these locations would probably not be possible.
    
    By initializing current_trace to &nop_trace where it is declared,
    current_trace will never be NULL, and we can remove all these
    checks of current_trace being NULL which never needed to be
    checked in the first place.
    
    Cc: Dan Carpenter <dan.carpenter@oracle.com>
    Cc: Hiraku Toyooka <hiraku.toyooka.gu@hitachi.com>
    Signed-off-by: default avatarSteven Rostedt <rostedt@goodmis.org>
    d840f718
trace.c 122 KB