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Message-ID: <1551744147.3771.0.camel@kernel.org>
Subject: Re: [PATCH 2/2] tracing: Use strncpy instead of memcpy for string
 keys in hist triggers
From:   Tom Zanussi <zanussi@kernel.org>
To:     Steven Rostedt <rostedt@goodmis.org>,
        Tom Zanussi <tom.zanussi@linux.intel.com>
Cc:     linux-kernel@vger.kernel.org, linux-rt-users@vger.kernel.org,
        Namhyung Kim <namhyung@kernel.org>
Date:   Mon, 04 Mar 2019 18:02:27 -0600
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On Mon, 2019-03-04 at 18:45 -0500, Steven Rostedt wrote:
> On Mon, 04 Mar 2019 16:31:40 -0600
> Tom Zanussi <tom.zanussi@linux.intel.com> wrote:
> 
> > > Hmm, I don't think it's really necessary - it's not used in a key
> > > so
> > > don't care about anything after the null, and TASK_COMM_LEN is
> > > used
> > > in
> > > the memcpy.  
> > 
> > Never mind, yeah, it would make sense to do this, will create
> > another
> > patch...
> 
> And probably should change the memcpy() of comm in
> kernel/trace/trace.c
> too. It could be that memcpy() is a little bit faster than strncpy(),
> and this is done on scheduling switches when tracing is active, but
> still, I'm starting to think that isn't a good choice.
> 

OK, will add that too.

Tom


> -- Steve