lkml.org 
[lkml]   [2012]   [Feb]   [28]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH v2] consolidate WARN_...ONCE() static variables
On Tue, 28 Feb 2012 08:02:40 +0000 "Jan Beulich" <JBeulich@suse.com> wrote:
> >>> On 28.02.12 at 08:44, Andrew Morton <akpm@linux-foundation.org> wrote:
> > On Tue, 28 Feb 2012 07:41:54 +0000 "Jan Beulich" <JBeulich@suse.com> wrote:
> >
> >> >>> On 28.02.12 at 01:03, Andrew Morton <akpm@linux-foundation.org> wrote:
> >> > On Mon, 27 Feb 2012 15:10:34 +0000
> >> > "Jan Beulich" <JBeulich@suse.com> wrote:
> >> >
> >> >> Due to the alignment of following variables, these typically consume
> >> >> more than just the single byte that 'bool' requires, and as there are
> >> >> a few hundred instances, the cache pollution (not so much the waste of
> >> >> memory) sums up. Put these variables into their own section, outside
> >> >> of any half way frequently used memory range.
> >> >>
> >> >> v2: Do the same also to the __warned variable of rcu_lockdep_assert().
> >> >> (Don't, however, include the ones used by printk_once() and alike, as
> >> >> they can potentially be hot.)
> >> >
> >> > I have a bad feeling that I still don't understand this patch. Ho hum.
> >> >
> >> > What are the rules for the new .data.unlikely section? When should
> >> > people put variables into this section? Perhaps we can document this
> >> > somewhere?
> >>
> >> If I knew the "where" part of this, I could put together a few sentences.
> >> I just grep-ed through Documentation/, without finding e.g. any rules
> >> or guidelines for using {,un}likely()...
> >>
> >
> > At the definition site in vmlinux.lds?
>
> Sorry, Andrew, but this makes no sense to me.

I really don't care - anywhere you like. Just the darn changelog, if
nowhere else.

I still don't have an answer to my question :( Some statement
describing what the new section is *for*. Seems a pretty important
thing?




\
 
 \ /
  Last update: 2012-02-28 09:13    [from the cache]
©2003-2011 Jasper Spaans