Re: [PATCH] perf, tools, script: Allow adding and removing fields

[Jiri Olsa <jolsa@redhat.com>]

On Fri, May 05, 2017 at 12:43:40PM -0700, Andi Kleen wrote:
> On Fri, May 05, 2017 at 09:57:54AM +0200, Jiri Olsa wrote:
> > On Thu, May 04, 2017 at 03:26:20PM -0700, Andi Kleen wrote:
> > > On Tue, May 02, 2017 at 08:41:47AM +0200, Jiri Olsa wrote:
> > > > On Mon, May 01, 2017 at 12:47:46PM -0700, Andi Kleen wrote:
> > > > > From: Andi Kleen <ak@linux.intel.com>
> > > > > 
> > > > > With perf script it is common that we just want to add or remove a field.
> > > > > Currently this requires figuring out the long list of default fields and
> > > > > specifying them first, and then adding/removing the new field.
> > > > > 
> > > > > This patch adds a new + - syntax to merely add or remove fields,
> > > > > that allows more succint and clearer command lines
> > > > > 
> > > > > For example to remove the comm field from PMU samples:
> > > > > 
> > > > > Previously
> > > > > 
> > > > > perf script -F pid,cpu,time,event,sym,ip,dso,period
> > > > > 	    0 [000] 504345.383126:          1 cycles:  ffffffff90060c66 native_write_msr ([kernel.kallsyms])
> > > > > 
> > > > > with the new syntax
> > > > > 
> > > > > perf script -F -comm
> > > > > 	    0 [000] 504345.383126:          1 cycles:  ffffffff90060c66 native_write_msr ([kernel.kallsyms])
> > > > 
> > > > 
> > > > I haven't checked deeply yet, but I'm getting different pids
> > > > with the new syntax, perhaps some mixing with tids column?
> > > 
> > > Cannot reproduce. Do you have an exact command line?
> > > 
> > > The patch shouldn't really change any columns.
> > >
> > 
> > [jolsa@krava perf]$ ./perf record -a
> 
> I looked at this, and I don't think it's different with my patch. 
> 
> Any time you set fields you get different output versus default:
> 
> 
> % perf script -F pid,cpu,time,event,sym,ip,dso,period,comm 
> 
> vs 
> 
> % perf script
> 
> First gives PID second TID.
> 
> It would be good to fix, but I don't think it should block my patch.

your changelog says those 2 commands give same output,
so either fix the changelog or provide related fix

thanks,
jirka