[PATCH 0/4 v2] sparc32: SMP IPI patches

[PATCH 0/4 v2] sparc32: SMP IPI patches

[Daniel Hellstrom]

Hello Dave,

I have made a new set of IPI patches, this time it includes patches for 
all SPARC32 architectures. It looks to me as if sun4d does not have a 
pending soft-IRQ register, so I handle it as a normal hard IRQ.

I'm not sure if I should add a STBAR/memory barrier or a spinlock to the 
sun4d implementation of smp4d_ipi_{single,mask_one,resched}. I'm a bit 
worried that the memory write happens after the IPI is generated to the 
other CPUs. Also, I'm not sure that IRQ14 is the best choice for IPI, 
the best is probably of put it on a separate IRQ but I don't know if 
there are free IRQs.

I hope that someone could try SMP on sun4m and sun4d with these patches.

Thanks,
Daniel

---

 arch/sparc/Kconfig                  |    3 +-
 arch/sparc/include/asm/cpudata_32.h |    5 ++
 arch/sparc/include/asm/leon.h       |    4 +-
 arch/sparc/include/asm/smp_32.h     |   22 +++----
 arch/sparc/kernel/entry.S           |   45 +++++++++++++-
 arch/sparc/kernel/irq.h             |    6 ++
 arch/sparc/kernel/irq_32.c          |   10 +++
 arch/sparc/kernel/leon_smp.c        |  109 
++++++++++++++++++++++++++++++++++-
 arch/sparc/kernel/smp_32.c          |   52 +++++++++++++++--
 arch/sparc/kernel/sun4d_irq.c       |    9 +++
 arch/sparc/kernel/sun4d_smp.c       |   79 +++++++++++++++++++++++++
 arch/sparc/kernel/sun4m_smp.c       |   29 +++++++++
 12 files changed, 345 insertions(+), 28 deletions(-)

Re: [PATCH 0/4 v2] sparc32: SMP IPI patches

[David Miller]

From: Daniel Hellstrom <daniel@gaisler.com>
Date: Mon, 02 May 2011 12:07:49 +0200

> I have made a new set of IPI patches, this time it includes patches
> for all SPARC32 architectures. It looks to me as if sun4d does not
> have a pending soft-IRQ register, so I handle it as a normal hard IRQ.
> 
> I'm not sure if I should add a STBAR/memory barrier or a spinlock to
> the sun4d implementation of smp4d_ipi_{single,mask_one,resched}. I'm a
> bit worried that the memory write happens after the IPI is generated
> to the other CPUs. Also, I'm not sure that IRQ14 is the best choice
> for IPI, the best is probably of put it on a separate IRQ but I don't
> know if there are free IRQs.
> 
> I hope that someone could try SMP on sun4m and sun4d with these
> patches.

I'm not going to hold these patches back, if we find bugs that
need to be fixed on sun4m/sun4d then we will simply fix them.

Thanks for fixing a problem we've had for such a long time.

Re: [PATCH 0/4 v2] sparc32: SMP IPI patches

[Daniel Hellstrom]

David Miller wrote:

>From: Daniel Hellstrom <daniel@gaisler.com>
>Date: Mon, 02 May 2011 12:07:49 +0200
>
>  
>
>>I have made a new set of IPI patches, this time it includes patches
>>for all SPARC32 architectures. It looks to me as if sun4d does not
>>have a pending soft-IRQ register, so I handle it as a normal hard IRQ.
>>
>>I'm not sure if I should add a STBAR/memory barrier or a spinlock to
>>the sun4d implementation of smp4d_ipi_{single,mask_one,resched}. I'm a
>>bit worried that the memory write happens after the IPI is generated
>>to the other CPUs. Also, I'm not sure that IRQ14 is the best choice
>>for IPI, the best is probably of put it on a separate IRQ but I don't
>>know if there are free IRQs.
>>
>>I hope that someone could try SMP on sun4m and sun4d with these
>>patches.
>>    
>>
>
>I'm not going to hold these patches back, if we find bugs that
>need to be fixed on sun4m/sun4d then we will simply fix them.
>
>Thanks for fixing a problem we've had for such a long time.
>  
>
Thanks for applying these pathes. From now on LEON SMP users can run 
vanilla kernels.

Daniel