[PATCH] m68knommu: ColdFire add support for kernel preemption

[PATCH] m68knommu: ColdFire add support for kernel preemption

[Greg Ungerer]

From: Sebastian Siewior <bigeasy@linutronix.de>

As the subject says this patch adds the support for kernel preemption
on m68knommu Coldfire. I thing the same changes could be applied to
68360 & 68328 but since I don't have the HW for testing, I don't touch it.

Signed-off-by: Sebastian Siewior <bigeasy@linutronix.de>
Signed-off-by: Greg Ungerer <gerg@uclinux.org>
---


diff -Naurp linux-2.6.25/arch/m68knommu/kernel/asm-offsets.c linux-2.6.25-uc0/arch/m68knommu/kernel/asm-offsets.c
--- linux-2.6.25/arch/m68knommu/kernel/asm-offsets.c	2008-04-17 12:49:44.000000000 +1000
+++ linux-2.6.25-uc0/arch/m68knommu/kernel/asm-offsets.c	2008-03-28 15:29:06.000000000 +1000
@@ -91,6 +91,7 @@ int main(void)
 	DEFINE(TI_TASK, offsetof(struct thread_info, task));
 	DEFINE(TI_EXECDOMAIN, offsetof(struct thread_info, exec_domain));
 	DEFINE(TI_FLAGS, offsetof(struct thread_info, flags));
+	DEFINE(TI_PREEMPTCOUNT, offsetof(struct thread_info, preempt_count));
 	DEFINE(TI_CPU, offsetof(struct thread_info, cpu));
 
 	return 0;
diff -Naurp linux-2.6.25/arch/m68knommu/platform/coldfire/entry.S linux-2.6.25-uc0/arch/m68knommu/platform/coldfire/entry.S
--- linux-2.6.25/arch/m68knommu/platform/coldfire/entry.S	2008-04-17 12:49:44.000000000 +1000
+++ linux-2.6.25-uc0/arch/m68knommu/platform/coldfire/entry.S	2008-05-01 11:58:21.000000000 +1000
@@ -106,6 +106,22 @@ ret_from_exception:
 	btst	#5,%sp@(PT_SR)		/* check if returning to kernel */
 	jeq	Luser_return		/* if so, skip resched, signals */
 
+#ifdef CONFIG_PREEMPT
+	movel	%sp,%d1			/* get thread_info pointer */
+	andl	#-THREAD_SIZE,%d1	/* at base of kernel stack */
+	movel	%d1,%a0
+	movel	%a0@(TI_FLAGS),%d1	/* get thread_info->flags */
+	andl	#_TIF_NEED_RESCHED,%d1
+	jeq	Lkernel_return
+
+	movel	%a0@(TI_PREEMPTCOUNT),%d1
+	cmpl	#0,%d1
+	jne	Lkernel_return
+
+	pea	Lkernel_return
+	jmp	preempt_schedule_irq	/* preempt the kernel */
+#endif
+
 Lkernel_return:
 	moveml	%sp@,%d1-%d5/%a0-%a2
 	lea	%sp@(32),%sp		/* space for 8 regs */

Re: [PATCH] m68knommu: ColdFire add support for kernel preemption

[Andrew Morton]

On Thu, 1 May 2008 12:16:29 +1000
Greg Ungerer <gerg@snapgear.com> wrote:

> Subject: [PATCH] m68knommu: ColdFire add support for kernel preemption

Please find a way to get your patch queue into linux-next so that others
get some visibility into what you're brewing earlier than
last-day-of-the-merge-window?

Also, when emailing patches like this I do think that it's best that they
be sequence-numbered, even if they are all non-overlapping and unrelated. 
Because it allows the recipient to check that none got lost.

Thanks.

Re: [PATCH] m68knommu: ColdFire add support for kernel preemption

[Greg Ungerer]

Hi Andrew,

Andrew Morton wrote:
> On Thu, 1 May 2008 12:16:29 +1000
> Greg Ungerer <gerg@snapgear.com> wrote:
> 
>> Subject: [PATCH] m68knommu: ColdFire add support for kernel preemption
> 
> Please find a way to get your patch queue into linux-next so that others
> get some visibility into what you're brewing earlier than
> last-day-of-the-merge-window?

Is a git tree the only way?


> Also, when emailing patches like this I do think that it's best that they
> be sequence-numbered, even if they are all non-overlapping and unrelated. 
> Because it allows the recipient to check that none got lost.

Ok.

Regards
Greg



------------------------------------------------------------------------
Greg Ungerer  --  Chief Software Dude       EMAIL:     gerg@snapgear.com
SnapGear -- a Secure Computing Company      PHONE:       +61 7 3435 2888
825 Stanley St,                             FAX:         +61 7 3891 3630
Woolloongabba, QLD, 4102, Australia         WEB: http://www.SnapGear.com

Re: [PATCH] m68knommu: ColdFire add support for kernel preemption

[Sebastian Siewior]

* Greg Ungerer | 2008-05-02 17:19:22 [+1000]:

> Hi Andrew,
Hi Greg,

> Andrew Morton wrote:
>> On Thu, 1 May 2008 12:16:29 +1000
>> Greg Ungerer <gerg@snapgear.com> wrote:
>>> Subject: [PATCH] m68knommu: ColdFire add support for kernel preemption
>> Please find a way to get your patch queue into linux-next so that others
>> get some visibility into what you're brewing earlier than
>> last-day-of-the-merge-window?
>
> Is a git tree the only way?
Others (Greg KH for instance, i2c) have quilt queues.

> Regards
> Greg

Sebastian

Re: [PATCH] m68knommu: ColdFire add support for kernel preemption

[Andrew Morton]

On Fri, 2 May 2008 10:37:55 +0200 Sebastian Siewior <lkml@ml.breakpoint.cc> wrote:

> >>> Subject: [PATCH] m68knommu: ColdFire add support for kernel preemption
> >> Please find a way to get your patch queue into linux-next so that others
> >> get some visibility into what you're brewing earlier than
> >> last-day-of-the-merge-window?
> >
> > Is a git tree the only way?
> Others (Greg KH for instance, i2c) have quilt queues.

Yup.  Examples:

ftp://ftp.kernel.org/pub/linux/kernel/people/agk/patches/2.6/editing/
http://ozlabs.org/~rusty/kernel/rr-latest
http://www.kernel.org/pub/linux/kernel/people/gregkh/gregkh-2.6/gregkh-02-usb

Note how you can publish subsets of your patchset by bracketing them with
"# MM_PATCHES_START" and "# MM_PATCHES_END" for -mm, and "#
NEXT_PATCHES_START" and "# NEXT_PATCHES_END" for linux-next.

Re: [PATCH] m68knommu: ColdFire add support for kernel preemption

[Greg Ungerer]

Hi Andrew,

Andrew Morton wrote:
> On Fri, 2 May 2008 10:37:55 +0200 Sebastian Siewior <lkml@ml.breakpoint.cc> wrote:
> 
>>>>> Subject: [PATCH] m68knommu: ColdFire add support for kernel preemption
>>>> Please find a way to get your patch queue into linux-next so that others
>>>> get some visibility into what you're brewing earlier than
>>>> last-day-of-the-merge-window?
>>> Is a git tree the only way?
>> Others (Greg KH for instance, i2c) have quilt queues.
> 
> Yup.  Examples:
> 
> ftp://ftp.kernel.org/pub/linux/kernel/people/agk/patches/2.6/editing/
> http://ozlabs.org/~rusty/kernel/rr-latest
> http://www.kernel.org/pub/linux/kernel/people/gregkh/gregkh-2.6/gregkh-02-usb
> 
> Note how you can publish subsets of your patchset by bracketing them with
> "# MM_PATCHES_START" and "# MM_PATCHES_END" for -mm, and "#
> NEXT_PATCHES_START" and "# NEXT_PATCHES_END" for linux-next.

I decided to go the git route.

Here is a git tree for the collection of patches for the m68knommu
architecture that I intend for the 2.6.27 merge window.

git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu.git for-linus

I have created a general uclinux changes git tree as well,

git://git.kernel.org/pub/scm/linux/kernel/git/gerg/uclinux.git for-linus

though currently I have nothing queued for that.

Regards
Greg



------------------------------------------------------------------------
Greg Ungerer  --  Chief Software Dude       EMAIL:     gerg@snapgear.com
Secure Computing Corporation                PHONE:       +61 7 3435 2888
825 Stanley St,                             FAX:         +61 7 3891 3630
Woolloongabba, QLD, 4102, Australia         WEB: http://www.SnapGear.com

Re: [PATCH] m68knommu: ColdFire add support for kernel preemption

[Andrew Morton]

On Mon, 23 Jun 2008 15:32:53 +1000 Greg Ungerer <gerg@snapgear.com> wrote:

> Hi Andrew,
> 
> Andrew Morton wrote:
> > On Fri, 2 May 2008 10:37:55 +0200 Sebastian Siewior <lkml@ml.breakpoint.cc> wrote:
> > 
> >>>>> Subject: [PATCH] m68knommu: ColdFire add support for kernel preemption
> >>>> Please find a way to get your patch queue into linux-next so that others
> >>>> get some visibility into what you're brewing earlier than
> >>>> last-day-of-the-merge-window?
> >>> Is a git tree the only way?
> >> Others (Greg KH for instance, i2c) have quilt queues.
> > 
> > Yup.  Examples:
> > 
> > ftp://ftp.kernel.org/pub/linux/kernel/people/agk/patches/2.6/editing/
> > http://ozlabs.org/~rusty/kernel/rr-latest
> > http://www.kernel.org/pub/linux/kernel/people/gregkh/gregkh-2.6/gregkh-02-usb
> > 
> > Note how you can publish subsets of your patchset by bracketing them with
> > "# MM_PATCHES_START" and "# MM_PATCHES_END" for -mm, and "#
> > NEXT_PATCHES_START" and "# NEXT_PATCHES_END" for linux-next.
> 
> I decided to go the git route.
> 
> Here is a git tree for the collection of patches for the m68knommu
> architecture that I intend for the 2.6.27 merge window.
> 
> git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu.git for-linus
> 
> I have created a general uclinux changes git tree as well,
> 
> git://git.kernel.org/pub/scm/linux/kernel/git/gerg/uclinux.git for-linus
> 
> though currently I have nothing queued for that.
> 

Great, thanks.  But can we get them into linux-next please?  I'll pick
them up via that route.

Re: [PATCH] m68knommu: ColdFire add support for kernel preemption

[Stephen Rothwell]

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Hi Greg,

On Sun, 22 Jun 2008 22:51:02 -0700 Andrew Morton <akpm@linux-foundation.org> wrote:
>
> On Mon, 23 Jun 2008 15:32:53 +1000 Greg Ungerer <gerg@snapgear.com> wrote:
> 
> > Here is a git tree for the collection of patches for the m68knommu
> > architecture that I intend for the 2.6.27 merge window.
> > 
> > git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu.git for-linus

Added today (slipped it in at the end).

> > I have created a general uclinux changes git tree as well,
> > 
> > git://git.kernel.org/pub/scm/linux/kernel/git/gerg/uclinux.git for-linus

This tree currently has no for-linus branch.  You should create one (even
if it just a subset of Linus' tree).  I've added it using its master
branch for now, please let me know when it is fixed.

Also, these branches would normally be called for-next.  Most people keep
for-linus for bug fixes for the current release.  If you decide to change
the branch name, just let me know.

Repeat of the rules for linux-next: anything included must have been
posted somewhere appropriate, reviewed and unit tested (i.e. your tree
should build for you).

> Great, thanks.  But can we get them into linux-next please?  I'll pick
> them up via that route.

Done.

-- 
Cheers,
Stephen Rothwell                    sfr@canb.auug.org.au
http://www.canb.auug.org.au/~sfr/

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Re: [PATCH] m68knommu: ColdFire add support for kernel preemption

[Greg Ungerer]

Hi Stephen,

Stephen Rothwell wrote:
> Hi Greg,
> 
> On Sun, 22 Jun 2008 22:51:02 -0700 Andrew Morton <akpm@linux-foundation.org> wrote:
>> On Mon, 23 Jun 2008 15:32:53 +1000 Greg Ungerer <gerg@snapgear.com> wrote:
>>
>>> Here is a git tree for the collection of patches for the m68knommu
>>> architecture that I intend for the 2.6.27 merge window.
>>>
>>> git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu.git for-linus
> 
> Added today (slipped it in at the end).

Great, thanks.


>>> I have created a general uclinux changes git tree as well,
>>>
>>> git://git.kernel.org/pub/scm/linux/kernel/git/gerg/uclinux.git for-linus
> 
> This tree currently has no for-linus branch.  You should create one (even
> if it just a subset of Linus' tree).  I've added it using its master
> branch for now, please let me know when it is fixed.

Ok, fixed now. There is an empty for-linus branch there.


> Also, these branches would normally be called for-next.  Most people keep
> for-linus for bug fixes for the current release.  If you decide to change
> the branch name, just let me know.

Ok, done too. Branches named for-next exist in both. The patches
on the for-linus branch in the m68knommu.git are now on the
for-next branch.

Do I need to send a request to Linus to pull this into his
tree during the next merge window?  Or will it migrate up
from linux-next?


> Repeat of the rules for linux-next: anything included must have been
> posted somewhere appropriate, reviewed and unit tested (i.e. your tree
> should build for you).
> 
>> Great, thanks.  But can we get them into linux-next please?  I'll pick
>> them up via that route.
> 
> Done.

Thanks
Greg


------------------------------------------------------------------------
Greg Ungerer  --  Chief Software Dude       EMAIL:     gerg@snapgear.com
SnapGear -- a Secure Computing Company      PHONE:       +61 7 3435 2888
825 Stanley St,                             FAX:         +61 7 3891 3630
Woolloongabba, QLD, 4102, Australia         WEB: http://www.SnapGear.com

Re: [PATCH] m68knommu: ColdFire add support for kernel preemption

[Andrew Morton]

On Mon, 23 Jun 2008 23:23:08 +1000 Greg Ungerer <gerg@snapgear.com> wrote:

> Do I need to send a request to Linus to pull this into his
> tree during the next merge window?

Yes, you do - nothing has changed in that regard.

>  Or will it migrate up
> from linux-next?

Nope, linux-next is a testing tree only.

Re: [PATCH] m68knommu: ColdFire add support for kernel preemption

[Stephen Rothwell]

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Hi Greg,

On Mon, 23 Jun 2008 23:23:08 +1000 Greg Ungerer <gerg@snapgear.com> wrote:
>
> Ok, done too. Branches named for-next exist in both. The patches
> on the for-linus branch in the m68knommu.git are now on the
> for-next branch.

I have updated my info, thanks.

> Do I need to send a request to Linus to pull this into his
> tree during the next merge window?  Or will it migrate up
> from linux-next?

Andrew has answered these.

-- 
Cheers,
Stephen Rothwell                    sfr@canb.auug.org.au
http://www.canb.auug.org.au/~sfr/

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