Re: [PATCH 06/12] perf report/top: Add 'k' hotkey to zoom directly into the kernel map

From: Namhyung Kim
Date: Sat Dec 21 2019 - 02:20:25 EST


On Fri, Dec 20, 2019 at 9:17 PM Arnaldo Carvalho de Melo
<acme@xxxxxxxxxx> wrote:
>
> Em Fri, Dec 20, 2019 at 03:48:23PM +0900, Namhyung Kim escreveu:
> > On Tue, Dec 17, 2019 at 11:49 PM Arnaldo Carvalho de Melo <acme@xxxxxxxxxx> wrote:
> > > From: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
> > > As a convenience, equivalent to pressing Enter in a line with a kernel
> > > symbol and then selecting "Zoom" into the kernel DSO.
>
> > We already have 'd' key for 'zoom into current dso'.
>
> Right, current DSO, 'k' is equivalent to:
>
> 1. Navigate to a kernel map entry
> 2. Press 'd'
>
> And also to:
>
> 1. Navigate to a kernel map entry
> 2. Press ENTER
> 3. Navigate to "Zoom into Kernel DSO"
> 4. Press ENTER
>
> One key versus 2 or four.
>
> > Do you really want 'k' for kernel specially?
>
> I thought kernel hackers would like the convenience, doing:
>
> perf top + k
>
> To get the main kernel samples looks faster than:
>
> perf top -e cycles:k
>
> And those are not even equivalent, as cycles:k will show everything in
> ring 0, while 'perf top + k' will show just what is in the kernel _and_
> in the main kernel map.

I'm fine with adding 'k' key itself, but I thought a bit strange when
it suggests kernel even with user DSOs.

Thanks
Namhyung