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    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?




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