• Steven Rostedt (Red Hat)'s avatar
    tracing: Fix showing function event in available_events · 36b53e8b
    Steven Rostedt (Red Hat) authored
    commit d045437a upstream.
    
    The ftrace:function event is only displayed for parsing the function tracer
    data. It is not used to enable function tracing, and does not include an
    "enable" file in its event directory.
    
    Originally, this event was kept separate from other events because it did
    not have a ->reg parameter. But perf added a "reg" parameter for its use
    which caused issues, because it made the event available to functions where
    it was not compatible for.
    
    Commit 9b63776f "tracing: Do not enable function event with enable"
    added a TRACE_EVENT_FL_IGNORE_ENABLE flag that prevented the function event
    from being enabled by normal trace events. But this commit missed keeping
    the function event from being displayed by the "available_events" directory,
    which is used to show what events can be enabled by set_event.
    
    One documented way to enable all events is to:
    
     cat available_events > set_event
    
    But because the function event is displayed in the available_events, this
    now causes an INVALID error:
    
     cat: write error: Invalid argument
    Reported-by: default avatarChunyu Hu <chuhu@redhat.com>
    Fixes: 9b63776f "tracing: Do not enable function event with enable"
    Signed-off-by: default avatarSteven Rostedt <rostedt@goodmis.org>
    Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
    36b53e8b
trace_events.c 77 KB