Re: [PATCH 0/3] DAPL support on s390x platform

Martin Schwidefsky
2014-12-12T08:19:04Z

On Wed, 10 Dec 2014 17:27:38 +0100
Utz Bacher <utz.bacher-tA70FqPdS9bQT0dZR+AlfA@public.gmane.org> wrote:

> Yishai Hadas <yishaih-LDSdmyG8hGV8YrgS2mwiifqBs+8SCbDb@public.gmane.org> wrote on 12.11.2014 13:38:49:
> [...]
> > On 11/12/2014 1:22 AM, Roland Dreier wrote:
> > > On Wed, Nov 5, 2014 at 7:04 AM, Utz Bacher <utz.bacher-tA70FqPdS9bQT0dZR+AlfA@public.gmane.org>
> wrote:
> > >> (B) Status of patches
> > >> 1. kernel code -- the new system call: reviewed, acked and accepted by
> the
> > >> s390x maintainer Martin Schwidefsky (2014/10/13), so we will have that
> > >> system call in the s390x kernel.
> > >> 2. libibverbs -- define barriers on s390x: Looking for your feedback.
> We
> > >> understand there have been no general objections so far.
> > >> 3. libmlx4 -- provide MMIO abstraction: reviewed by the Mellanox
> > >> maintainers and we understand they would apply this once you give the
> go
> > >> for the overall set.
> > >> Previously, a patch to DAPL to build on s390x has been accepted
> already
> > >> (Arlin Davis, 2014/09/02).
> [...]
> > > If Mellanox is willing to take on the maintenance burden of changing
> > > all MMIO access to an inline function, and if you're willing to take
> > > on the burden of knowing that every new adapter you support means
> > > tracking down and convincing the maintainer of the driver library,
> > > then I'm OK with adding the simple barrier patch to libibverbs. Could
> > > you please send the latest version of that patch to me?
> > >
> >
> > The libmlx4 patch should pass some performance regression before it can
> > be approved, this task is in progress in our side.
>
> so when the libmlx4 patch passed the performance regression runs
> successfully, we would assume Roland and Yishai acknowledge the changes.
> Can we correctly expect these patches (without further changes) appearing
> in libmlx4 on top of 1.0.6 and libibverbs on top of 1.1.8?
> Just checking before we talk to distribution partners, so that everyone
> stays in sync with upstream. Martin Schwidefsky is applying the kernel
> changes, too.

The kernel part just went upstream, with the following git commit:

commit 4eafad7febd482092b331ea72c37274d745956be
Author: Alexey Ishchuk <aishchuk-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org>
Date: Fri Nov 14 14:27:58 2014 +0100

s390/kernel: add system calls for PCI memory access

Add the new __NR_s390_pci_mmio_write and __NR_s390_pci_mmio_read
system calls to allow user space applications to access device PCI I/O
memory pages on s390x platform.

[ Martin Schwidefsky: some code beautification ]

Signed-off-by: Alexey Ishchuk <aishchuk-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org>
Signed-off-by: Martin Schwidefsky <schwidefsky-tA70FqPdS9bQT0dZR+AlfA@public.gmane.org>

--
blue skies,
Martin.

"Reality continues to ruin my life." - Calvin.