> From: Andrew Morton [mailto:[email protected]]
> > ACPI: make it so acpismp=force works (reported by Andrew Morton)
> But prior to 2.5.72, CPU enumeration worked fine without
> acpismp=force.
> Now it is required. How come?
(I'm taking the liberty to update the subject, which I accidentally left
blank)
Because 2.4 has that behavior. One objection that people raised to
applying the 2.4 ACPI patch was that it changed that behavior. So I made
an effort to keep it there.
I think out of sheer inertia I also re-added it to the 2.5 tree.
Probably shouldn't have.
Does anyone have a reason why acpismp=force should be in 2.5/6? If not
I'll go ahead and zap it (again), and everyone should just be aware that
this is another way that 2.4 and 2.5 differ.
Regards -- Andy
"Grover, Andrew" <[email protected]> wrote:
>
> Does anyone have a reason why acpismp=force should be in 2.5/6?
I can't think of one.
> If not I'll go ahead and zap it (again)
zap away. Dave Jones is maintaining a "stuff which changed" document.
Please send him a paragraph.
On Mon, 2003-06-23 at 09:43, Grover, Andrew wrote:
> > From: Andrew Morton [mailto:[email protected]]
> > > ACPI: make it so acpismp=force works (reported by Andrew Morton)
>
> > But prior to 2.5.72, CPU enumeration worked fine without
> > acpismp=force.
> > Now it is required. How come?
>
> (I'm taking the liberty to update the subject, which I accidentally left
> blank)
>
> Because 2.4 has that behavior. One objection that people raised to
> applying the 2.4 ACPI patch was that it changed that behavior. So I made
> an effort to keep it there.
in 2.4 it is absolutely not mantadory; it's default actually if the cpu
advertises the "ht" flag.....
On Mon, 23 Jun 2003, Arjan van de Ven wrote:
> On Mon, 2003-06-23 at 09:43, Grover, Andrew wrote:
> > > From: Andrew Morton [mailto:[email protected]]
> > > > ACPI: make it so acpismp=force works (reported by Andrew Morton)
> >
> > > But prior to 2.5.72, CPU enumeration worked fine without
> > > acpismp=force.
> > > Now it is required. How come?
> >
> > (I'm taking the liberty to update the subject, which I accidentally left
> > blank)
> >
> > Because 2.4 has that behavior. One objection that people raised to
> > applying the 2.4 ACPI patch was that it changed that behavior. So I made
> > an effort to keep it there.
>
> in 2.4 it is absolutely not mantadory; it's default actually if the cpu
> advertises the "ht" flag.....
Right, enabling HT hasn't relied on "acpismp=force" since 2.4.18.
Requiring "acpismp=force" now in 2.4 or 2.5 is just a step backwards.
But when we changed to HT by default, I added bootparam "noht" to
disable it if it was found troublesome. Last time I checked, "noht"
was ineffectual on 2.5, and perhaps now it's ineffectual on 2.4.22-pre?
(If I remember right, in 2.5 it did have one effect, determining whether
the "ht" flag is shown in /proc/cpuinfo: but it was intended to be more
useful than that.)
Certainly reliance on "acpismp=force" should be removed if it's crept
back in. But what should we do about "noht"? Wave a fond goodbye,
and remove it's associated code and Documentation from 2.4 and 2.5
trees, rely on changing the BIOS setting instead? Or bring it back
into action?
Hugh
On Mon, Jun 23, 2003 at 12:46:38PM +0100, Hugh Dickins wrote:
> Certainly reliance on "acpismp=force" should be removed if it's crept
> back in. But what should we do about "noht"? Wave a fond goodbye,
> and remove it's associated code and Documentation from 2.4 and 2.5
> trees, rely on changing the BIOS setting instead? Or bring it back
> into action?
for 2.4 it's no problem to honor it really code wise; and it's
useful for machines where you can't disable HT in the bios but where
your particular workload doesn't positively benefit from HT.