Re: [PATCH v6 15/16] x86/hyperv: implement an MSI domain for root partition

From: Wei Liu <wei.liu@kernel.org>
To: Michael Kelley <mikelley@microsoft.com>
Cc: Wei Liu <wei.liu@kernel.org>,
	Linux on Hyper-V List <linux-hyperv@vger.kernel.org>,
	"virtualization@lists.linux-foundation.org" 
	<virtualization@lists.linux-foundation.org>,
	Linux Kernel List <linux-kernel@vger.kernel.org>,
	Vineeth Pillai <viremana@linux.microsoft.com>,
	Sunil Muthuswamy <sunilmut@microsoft.com>,
	Nuno Das Neves <nunodasneves@linux.microsoft.com>,
	"pasha.tatashin@soleen.com" <pasha.tatashin@soleen.com>,
	KY Srinivasan <kys@microsoft.com>,
	Haiyang Zhang <haiyangz@microsoft.com>,
	Stephen Hemminger <sthemmin@microsoft.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
	"maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT)"
	<x86@kernel.org>, "H. Peter Anvin" <hpa@zytor.com>
Subject: Re: [PATCH v6 15/16] x86/hyperv: implement an MSI domain for root partition
Date: Thu, 4 Feb 2021 18:43:11 +0000	[thread overview]
Message-ID: <20210204184311.xuqlrenlth2vi236@liuwe-devbox-debian-v2> (raw)
In-Reply-To: <MWHPR21MB15934AD184476EF14CF4C732D7B39@MWHPR21MB1593.namprd21.prod.outlook.com>

On Thu, Feb 04, 2021 at 06:40:55PM +0000, Michael Kelley wrote:
> From: Wei Liu <wei.liu@kernel.org> Sent: Thursday, February 4, 2021 9:57 AM
[...]
> > I've got the following diff to fix both issues. If you're happy with the
> > changes, can you give your Reviewed-by? That saves a round of posting.
> > 
> > diff --git a/arch/x86/hyperv/irqdomain.c b/arch/x86/hyperv/irqdomain.c
> > index 0cabc9aece38..fa71db798465 100644
> > --- a/arch/x86/hyperv/irqdomain.c
> > +++ b/arch/x86/hyperv/irqdomain.c
> > @@ -1,7 +1,7 @@
> >  // SPDX-License-Identifier: GPL-2.0
> > 
> >  /*
> > - * for Linux to run as the root partition on Microsoft Hypervisor.
> > + * Irqdomain for Linux to run as the root partition on Microsoft Hypervisor.
> >   *
> >   * Authors:
> >   *  Sunil Muthuswamy <sunilmut@microsoft.com>
> > @@ -20,7 +20,7 @@ static int hv_map_interrupt(union hv_device_id device_id, bool level,
> >         struct hv_device_interrupt_descriptor *intr_desc;
> >         unsigned long flags;
> >         u64 status;
> > -       cpumask_t mask = CPU_MASK_NONE;
> > +       const cpumask_t *mask;
> >         int nr_bank, var_size;
> > 
> >         local_irq_save(flags);
> > @@ -41,10 +41,10 @@ static int hv_map_interrupt(union hv_device_id device_id, bool
> > level,
> >         else
> >                 intr_desc->trigger_mode = HV_INTERRUPT_TRIGGER_MODE_EDGE;
> > 
> > -       cpumask_set_cpu(cpu, &mask);
> > +       mask = cpumask_of(cpu);
> >         intr_desc->target.vp_set.valid_bank_mask = 0;
> >         intr_desc->target.vp_set.format = HV_GENERIC_SET_SPARSE_4K;
> > -       nr_bank = cpumask_to_vpset(&(intr_desc->target.vp_set), &mask);
> > +       nr_bank = cpumask_to_vpset(&(intr_desc->target.vp_set), mask);
> 
> Can you just do the following and get rid of the 'mask' local entirely?
> 
> nr_bank = cpumask_to_vpset(&(intr_desc->target.vp_set), cpumask_of(cpu));

Sure. That can be done.

> 
> Either way,
> 
> Reviewed-by: Michael Kelley <mikelley@microsoft.com>

Thank you.

Wei.