Re: [patch] add optimized generic percpu accessors

From: Ingo Molnar
Date: Thu Jan 15 2009 - 07:23:27 EST



* Tejun Heo <tj@xxxxxxxxxx> wrote:

> Ingo Molnar wrote:
> > Is there any interim tree for us to pull into -tip? I'd rather not let
> > this grow too big, it will be harder and harder to debug any regressions.
> > Gradual progress is a lot more debuggable. Your initial patchset is
> > fantastic already (gives a ~0.2% kernel image size saving for defconfig),
> > so it's a very good start.
>
> Sans the last patch (I'm still working on it), the git tree is at...
>
> http://git.kernel.org/?p=linux/kernel/git/tj/misc.git;a=shortlog;h=x86-percpu-zerobased
> git://git.kernel.org/pub/scm/linux/kernel/git/tj/misc.git x86-percpu-zerobased
>
> And this happens to be the third time I wrote the above addresses in
> this thread. :-)

You know the drill: you have to explicitly ask for stuff to be pulled :-)

( Otherwise if i just pull it and you rebased it or were unhappy about it
in some fashion we all add stress that could have been avoided. )

So i've picked up these commits from you:

d060676: x86_64: misc clean up after the percpu update
6d459d9: x86_64: convert pda ops to wrappers around x86 percpu accessors
d7051ef: x86_64: make pda a percpu variable
4fe7fdf: x86_64: merge 64 and 32 SMP percpu handling
44f5fbd: x86_64: fold pda into percpu area on SMP
cc1d354: x86_64: use static _cpu_pda array
c701268: x86_64: load pointer to pda into %gs while brining up a CPU
7e36da9: x86_64: make percpu symbols zerobased on SMP
3fc860d: x86_32: make vmlinux_32.lds.S use PERCPU() macro
bc497c7: x86_64: Cleanup early setup_percpu references
769d780: x86: make early_per_cpu() a lvalue and use it
66cbc8e: x86_64: fix pda_to_op()

into tip/x86/percpu.

I did the following small reorganizations:

- i rebased them on top of tip/cpus4096, tip/x86/cleanups and
tip/x86/urgent - that is a stable base.

- i resolved the conflicts that arose due to recent cpumask and upstream
changes.

- i standardized the commit logs to the usual x86 style and added
Original-From: Mike Travis tags to those patches that were derived from
Mike's patches.

If they pass testing they'll be stable commits from that point on, and you
can base your git trees on that topic branch.

Could you please have a look at the end result? Here are the Git
coordinates for it:

git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip.git x86/percpu

If we are happy with it then these commits can be stable commits from now
on, and you can base your future changes on this Git tree, and i can pull
updates from you without having to rebase them.

Does that workflow sound OK to you?

Ingo
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/