Re: [Xen-devel] [PATCH v3 08/19] xen/arm: Introduce a initcall to update cpu_hwcaps by serror_op

[Wei Chen <Wei.Chen@xxxxxxx>]

Hi Julien,

On 2017/3/31 22:48, Julien Grall wrote:
> Hi Wei,
>
> On 31/03/17 14:07, Wei Chen wrote:
> > In the later patches of this series, we want to use the alternative
> > patching framework to avoid checking serror_op in every entries.
> > So we define a new cpu feature "SKIP_CHECK_PENDING_VSERROR" for
> > serror_op. When serror_op is not equal to SERROR_DIVERSE, this
> > feature will be set to cpu_hwcaps.
> >
> > Currently, the default serror_op is SERROR_DIVERSE, if we want to
> > change the serror_op value we have to place the serror parameter
> > in command line. It seems no problem to update cpu_hwcaps directly
> > in the serror parameter parsing function.
> >
> > While the default option will be diverse today, this may change in the
> > future. So we introduce this initcall to guarantee the cpu_hwcaps can be
> > updated no matter the serror parameter is placed in the command line
> > or not.
> >
> > Signed-off-by: Wei Chen <Wei.Chen@xxxxxxx>
> > Acked-by: Julien Grall <julien.grall@xxxxxxx>
> > Reviewed-by: Stefano Stabellini <sstabellini@xxxxxxxxxx>
> > ---
> > v2->v3
> > 1. Rewrite the commit message to make it easer to understand.
> > 2. Add Julien's Acked-by tag and Stefano's Reviewed-by tag.
> > ---
> >  xen/arch/arm/traps.c             | 9 +++++++++
> >  xen/include/asm-arm/cpufeature.h | 3 ++-
> >  2 files changed, 11 insertions(+), 1 deletion(-)
> >
> > diff --git a/xen/arch/arm/traps.c b/xen/arch/arm/traps.c
> > index 76cda59..9d4ee39 100644
> > --- a/xen/arch/arm/traps.c
> > +++ b/xen/arch/arm/traps.c
> > @@ -141,6 +141,15 @@ static void __init parse_serrors_behavior(const 
> > char *str)
> >  }
> >  custom_param("serrors", parse_serrors_behavior);
> >
> > +static int __init update_serrors_cpu_caps(void)
> > +{
> > +    if ( serrors_op != SERRORS_DIVERSE )
> > +        cpus_set_cap(SKIP_CHECK_PENDING_VSERROR);
> I have some comment regarding the name of the feature (see patch #18).
I will update it and send a new version.

> Cheers,
_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
https://lists.xen.org/xen-devel