• Steven Rostedt's avatar
    ftrace: Add default recursion protection for function tracing · 4740974a
    Steven Rostedt authored
    
    
    As more users of the function tracer utility are being added, they do
    not always add the necessary recursion protection. To protect from
    function recursion due to tracing, if the callback ftrace_ops does not
    specifically specify that it protects against recursion (by setting
    the FTRACE_OPS_FL_RECURSION_SAFE flag), the list operation will be
    called by the mcount trampoline which adds recursion protection.
    
    If the flag is set, then the function will be called directly with no
    extra protection.
    
    Note, the list operation is called if more than one function callback
    is registered, or if the arch does not support all of the function
    tracer features.
    Signed-off-by: default avatarSteven Rostedt <rostedt@goodmis.org>
    4740974a
ftrace.h 25 KB