RE: [PATCH 1/5] xen/memory: Introduce CONFIG_ARCH_ACQUIRE_RESOURCE

From: Paul Durrant <xadimgnik@gmail.com>
To: "'Andrew Cooper'" <andrew.cooper3@citrix.com>,
	"'Xen-devel'" <xen-devel@lists.xenproject.org>
Cc: "'Stefano Stabellini'" <sstabellini@kernel.org>,
	"'Julien Grall'" <julien@xen.org>, "'Wei Liu'" <wl@xen.org>,
	"'Michał Leszczyński'" <michal.leszczynski@cert.pl>,
	"'Jan Beulich'" <JBeulich@suse.com>,
	"'Hubert Jasudowicz'" <hubert.jasudowicz@cert.pl>,
	"'Volodymyr Babchuk'" <Volodymyr_Babchuk@epam.com>,
	"'Roger Pau Monné'" <roger.pau@citrix.com>
Subject: RE: [PATCH 1/5] xen/memory: Introduce CONFIG_ARCH_ACQUIRE_RESOURCE
Date: Thu, 30 Jul 2020 19:24:35 +0100	[thread overview]
Message-ID: <003301d6669e$addc2500$09946f00$@xen.org> (raw)
In-Reply-To: <33a10589-6890-b653-d8c2-7eb19a5e4929@citrix.com>

> -----Original Message-----
> From: Andrew Cooper <andrew.cooper3@citrix.com>
> Sent: 30 July 2020 18:34
> To: paul@xen.org; 'Xen-devel' <xen-devel@lists.xenproject.org>
> Cc: 'Jan Beulich' <JBeulich@suse.com>; 'Wei Liu' <wl@xen.org>; 'Roger Pau Monné'
> <roger.pau@citrix.com>; 'Stefano Stabellini' <sstabellini@kernel.org>; 'Julien Grall'
> <julien@xen.org>; 'Volodymyr Babchuk' <Volodymyr_Babchuk@epam.com>; 'Michał Leszczyński'
> <michal.leszczynski@cert.pl>; 'Hubert Jasudowicz' <hubert.jasudowicz@cert.pl>
> Subject: Re: [PATCH 1/5] xen/memory: Introduce CONFIG_ARCH_ACQUIRE_RESOURCE
> 
> On 30/07/2020 09:02, Paul Durrant wrote:
> >> -----Original Message-----
> >> From: Andrew Cooper <andrew.cooper3@citrix.com>
> >> Sent: 28 July 2020 12:37
> >> To: Xen-devel <xen-devel@lists.xenproject.org>
> >> Cc: Andrew Cooper <andrew.cooper3@citrix.com>; Jan Beulich <JBeulich@suse.com>; Wei Liu
> <wl@xen.org>;
> >> Roger Pau Monné <roger.pau@citrix.com>; Stefano Stabellini <sstabellini@kernel.org>; Julien Grall
> >> <julien@xen.org>; Volodymyr Babchuk <Volodymyr_Babchuk@epam.com>; Paul Durrant <paul@xen.org>;
> Michał
> >> Leszczyński <michal.leszczynski@cert.pl>; Hubert Jasudowicz <hubert.jasudowicz@cert.pl>
> >> Subject: [PATCH 1/5] xen/memory: Introduce CONFIG_ARCH_ACQUIRE_RESOURCE
> >>
> >> New architectures shouldn't be forced to implement no-op stubs for unused
> >> functionality.
> >>
> >> Introduce CONFIG_ARCH_ACQUIRE_RESOURCE which can be opted in to, and provide
> >> compatibility logic in xen/mm.h
> >>
> >> No functional change.
> > Code-wise, it looks fine, so...
> >
> > Reviewed-by: Paul Durrant <paul@xen.org>
> 
> Thanks,
> 
> >
> > ...but ...
> >
> >> Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
> >> ---
> >> CC: Jan Beulich <JBeulich@suse.com>
> >> CC: Wei Liu <wl@xen.org>
> >> CC: Roger Pau Monné <roger.pau@citrix.com>
> >> CC: Stefano Stabellini <sstabellini@kernel.org>
> >> CC: Julien Grall <julien@xen.org>
> >> CC: Volodymyr Babchuk <Volodymyr_Babchuk@epam.com>
> >> CC: Paul Durrant <paul@xen.org>
> >> CC: Michał Leszczyński <michal.leszczynski@cert.pl>
> >> CC: Hubert Jasudowicz <hubert.jasudowicz@cert.pl>
> >> ---
> >>  xen/arch/x86/Kconfig     | 1 +
> >>  xen/common/Kconfig       | 3 +++
> >>  xen/include/asm-arm/mm.h | 8 --------
> >>  xen/include/xen/mm.h     | 9 +++++++++
> >>  4 files changed, 13 insertions(+), 8 deletions(-)
> >>
> >> diff --git a/xen/arch/x86/Kconfig b/xen/arch/x86/Kconfig
> >> index a636a4bb1e..e7644a0a9d 100644
> >> --- a/xen/arch/x86/Kconfig
> >> +++ b/xen/arch/x86/Kconfig
> >> @@ -6,6 +6,7 @@ config X86
> >>  	select ACPI
> >>  	select ACPI_LEGACY_TABLES_LOOKUP
> >>  	select ARCH_SUPPORTS_INT128
> >> +	select ARCH_ACQUIRE_RESOURCE
> > ... I do wonder whether 'HAS_ACQUIRE_RESOURCE' is a better and more descriptive name.
> 
> We don't have a coherent policy for how to categorise these things.  I
> can change the name if you insist, but I'm not sure it makes a useful
> difference.
> 

Ok, it's fine. My R-b stands.

  Paul

> ~Andrew