lkml.org 
[lkml]   [2021]   [Jan]   [8]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH RFC cpumask 4/5] cpumask: Add "last" alias for cpu list specifications
On Wed, Jan 06, 2021 at 01:16:50PM -0800, Yury Norov wrote:
> On Wed, Jan 6, 2021 at 1:50 AM Peter Zijlstra <peterz@infradead.org> wrote:

> > Aside from the comments Yury made, on how all this is better in
> > bitmap_parselist(), how about doing s/last/N/ here? For me something
> > like: "4-N" reads much saner than "4-last".
> >
> > Also, it might make sense to teach all this about core/node topology,
> > but that's going to be messy. Imagine something like "Core1-CoreN" or
> > "Nore1-NodeN" to mean the mask all/{Core,Node}0.
>
> If you just want to teach bitmap_parselist() to "s/Core0/0-4", I think
> it's doable if we add a hook to a proper subsystem in bitmap_parselist().
>
> > And that is another feature that seems to be missing from parselist,
> > all/except.
>
> We already support groups in a range. I think it partially covers the
> proposed all/except.
>
> Can you share examples on what you miss?

The obvious one is the "all/Core0" example above, which would be
equivalent to "Core1-CoreN".

Another case that I don't think we can do today is something like, give
me SMT0 of each core.

I don't really see the use of the ranges thing, CPU enumeration just
isn't sane like that. Also, I should really add that randomization pass
to the CPU enumeration :-)

\
 
 \ /
  Last update: 2021-01-09 02:05    [W:7.673 / U:0.328 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site