On Thu, 30 Mar 2017 09:49:29 -0400 Steven Rostedt <[email protected]> wrote:
> On Thu, 30 Mar 2017 10:40:46 +0900 > Namhyung Kim <[email protected]> wrote: > > > Hi Masami, > > > > On Thu, Mar 30, 2017 at 9:54 AM, Masami Hiramatsu <[email protected]> > > wrote: > > > On Wed, 29 Mar 2017 10:46:21 +0900 > > > Namhyung Kim <[email protected]> wrote: > > > > > >> Hello, > > >> > > >> This patchset add 'function-fork' option to function tracer which > > >> makes pid filter to be inherited like 'event-fork' does. During the > > >> test, I found a bug of pid filter on an instance directory. The patch > > >> 1 fixes it and maybe it should go to the stable tree. > > >> > > >> The function-fork option is disabled by default as event-fork does, > > >> but we might consider changing the default since it seems to be more > > >> natural from an user's perspective IMHO. > > > > > > By the way, I thought that event-fork option also effected to > > > function tracer. Is there any reason we should separate those? > > > I mean, we can add "trace-fork" option instead of "function-fork" > > > for setting both pid filters at once. > > > > > > Thank you, > > > > I'm ok with combining two options. > > > > I prefer not. Mainly because they are two different mechanisms, and > only event-fork is available now. That sounds like implementation issue. From the viewpoint of users, they may want to use just one knob to filter both. And I didn't suggest replacing event-fork, but adding trace-fork for both, like a superset option. > trace-cmd will use ptrace if function > fork is needed. Having it separate will let trace-cmd know if it needs > to use ptrace or not for function forking. Yeah, that's a good workaround for older kernel. Thank you, -- Masami Hiramatsu <[email protected]>
