Re: [RFC PATCH 1/3] perf probe: Init symbol as kprobe if any pev is kprobe

[Wangnan (F)]

On 2015/6/27 15:29, Masami Hiramatsu wrote:
> On 2015/06/25 19:37, Wang Nan wrote:
> > Before this patch, add_perf_probe_events() init symbol maps only for
> > uprobe if the first pev passed to it is a uprobe event. However, with
> > the incoming BPF uprobe support, now it will be possible to pass an
> > array with combined kprobe and uprobe events to add_perf_probe_events().
> This description is not correct. Actually, add_perf_probe_events already
> supports mix of uprobes and kprobes. However, from the command line syntax
> constrains the first elements of the probe_event arrays must be kprobes.
> So, if the array starts with uprobes, no kprobes should be there.
>
> > This patch check all pevs instead of the first one, and init kernel
> > symbol if any events is not uprobe.
> Anyway, I prefer to call init_symbol_maps() with "false" :)

I also prefer "false", so I try to find whether all events are uprobe 
instead
of init_symbol_maps(true).

So for this patch only commit message needs to be corrected, the code is
no problem, right?

Thank you.

> Thank you,
>
> > Signed-off-by: Wang Nan <wangnan0@xxxxxxxxxx>
> > ---
> >   tools/perf/util/probe-event.c | 15 ++++++++++++++-
> >   1 file changed, 14 insertions(+), 1 deletion(-)
> >
> > diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
> > index b386d2f..a2b3026 100644
> > --- a/tools/perf/util/probe-event.c
> > +++ b/tools/perf/util/probe-event.c
> > @@ -2802,8 +2802,21 @@ int cleanup_perf_probe_event(struct perf_probe_event *pev)
> >   int add_perf_probe_events(struct perf_probe_event *pevs, int npevs, bool cleanup)
> >   {
> >   	int i, ret;
> > +	bool user_only = true;
> >   
> > -	ret = init_symbol_maps(pevs->uprobes);
> > +	/* If any pev is kprobe, init kernel symbols. */
> > +	for (i = 0; i < npevs; i++) {
> > +		if (!pevs[i].uprobes) {
> > +			user_only = false;
> > +			break;
> > +		}
> > +	}
> > +
> > +	/*
> > +	 * Compiler can drop user_only:
> > +	 *  ret = init_symbol_maps(i >= npevs);
> > +	 */
> > +	ret = init_symbol_maps(user_only);
> >   	if (ret < 0)
> >   		return ret;
> >   


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