linux-kernel - Re: [PATCH v4 07/12] tracing: Add synth_event

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <1580338724.6220.17.camel@kernel.org>
Date:   Wed, 29 Jan 2020 16:58:44 -0600
From:   Tom Zanussi <zanussi@...nel.org>
To:     Steven Rostedt <rostedt@...dmis.org>
Cc:     artem.bityutskiy@...ux.intel.com, mhiramat@...nel.org,
        linux-kernel@...r.kernel.org, linux-rt-users@...r.kernel.org
Subject: Re: [PATCH v4 07/12] tracing: Add synth_event_trace() and related
 functions

Hi Steve,

On Wed, 2020-01-29 at 16:09 -0500, Steven Rostedt wrote:
> On Wed, 29 Jan 2020 12:59:27 -0600
> Tom Zanussi <zanussi@...nel.org> wrote:
> 
> > +static struct synth_field *find_synth_field(struct synth_event
> > *event,
> > +					    const char
> > *field_name)
> > +{
> > +	struct synth_field *field = NULL;
> > +	unsigned int i;
> > +
> > +	for (i = 0; i < event->n_fields; i++) {
> > +		field = event->fields[i];
> > +		if (strcmp(field->name, field_name) == 0)
> > +			return field;
> > +	}
> > +
> > +	return NULL;
> > +}
> 
> Why duplicate all theses functions and not use them in the
> synth_event_trace() directly?
> 

Yes, find_synth_field() is used only once and is short, so I can just
add that into synth_event_add_val() directly.  And looking at
synth_event_add_val() and synth_event_add_next_val(), they're almost
identical and so can be made into a single function with a param for
the different parts (but still need to be exported separately so they
can be used with the piecewise API).

It would also be possible to have synth_event_trace() and
synth_event_trace_array() use synth_event_add_next_val() instead of
writing the fields directly but that would be more overhead for those
functions, which is why I avoided doing that.

Let me know if it's something else you're referring to, or if you want
me to do a v5 or a follow-on patch to do the first part above.

Thanks,

Tom

> -- Steve