[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
RE: [PATCH 20/22] xen/arm64: mm: Use per-pCPU page-tables
- To: Julien Grall <julien@xxxxxxx>, "xen-devel@xxxxxxxxxxxxxxxxxxxx" <xen-devel@xxxxxxxxxxxxxxxxxxxx>
- From: Henry Wang <Henry.Wang@xxxxxxx>
- Date: Sat, 7 Jan 2023 02:22:42 +0000
- Accept-language: zh-CN, en-US
- Arc-authentication-results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=arm.com; dmarc=pass action=none header.from=arm.com; dkim=pass header.d=arm.com; arc=none
- Arc-message-signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector9901; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=Coaca47qk/N0rae4zzA1XwE4RCQ6I/ay8ADLcscw32E=; b=BuMTaCce4+5ReNlA4XyGcL3rD6h1ALsTl7sKO8m6oOSwvxWQ5kCxKLphFQUKVnSzxQxNbO/D9sJpusyJL8EVChGT4A1OohqnRvi/5C7Mb6bi0P02iFvJIKUfqVCRvCv0gh/Q9qtpsBZaLi3GnZ8xhCK7m+qdOSIwZ2DvInUl1x7+m7Qn9b+YVSZrLdaKW79RBKZ8vj4BWZegDqhL5HT6aiZqGvChV0A9Bh9n/ctPZLdYqvQEuYce24m20050ht5Pp55ZjxWOlxPoRoEJbPzrOxx44vJdob60Rj1rIcG0U3VkpIyZ+1z7pqQc7ukxk6y/IJd4qogRG+409l+Htgs87w==
- Arc-seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=cC9oGbMlyeECtaoiA/sxan9Rpy03LjTF+hP89PiRyZuhDHWOkQPoSksFa3z0SzzjAajHYbY2DVCIN3SapmMDOuf0dGml2rivc5F1yc//vuTZ03LtQp8HjTXweKqvFU6DXnrMMijZhi9NriIm/IuD3K2l0SCBTZpqlcQN5sc+0s9n4M+3Bb6ePSJT+aIVwpQj9SLba4SuCjSJ2yrpIvHJX8W58J1IsLhXvOFavFTj6wC3uVYuwYpVRMTL02Q2oO6qLvp0gTrm5IqQOFWi1aGid1Gi4tDzOoJPDf0c6pKxWquVscmZwx6lBkck7AHlyuhya94oRGa7IEVTLtGYbg6L4Q==
- Authentication-results-original: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=arm.com;
- Cc: Julien Grall <jgrall@xxxxxxxxxx>, Stefano Stabellini <sstabellini@xxxxxxxxxx>, Bertrand Marquis <Bertrand.Marquis@xxxxxxx>, Volodymyr Babchuk <Volodymyr_Babchuk@xxxxxxxx>
- Delivery-date: Sat, 07 Jan 2023 02:23:05 +0000
- List-id: Xen developer discussion <xen-devel.lists.xenproject.org>
- Nodisclaimer: true
- Original-authentication-results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=arm.com;
- Thread-index: AQHZEUh12RKmuw645EafAVdnfeFYOK6RkuHggAAV9gCAALFqIA==
- Thread-topic: [PATCH 20/22] xen/arm64: mm: Use per-pCPU page-tables
Hi Julien,
> -----Original Message-----
> Subject: Re: [PATCH 20/22] xen/arm64: mm: Use per-pCPU page-tables
>
> Hi Henry,
>
> >> Subject: [PATCH 20/22] xen/arm64: mm: Use per-pCPU page-tables
> >>
> >> From: Julien Grall <jgrall@xxxxxxxxxx>
> >>
> >> At the moment, on Arm64, every pCPU are sharing the same page-tables.
> >
> > Nit: s/every pCPU are/ every pCPU is/
>
> I will fix it.
Thank you.
>
> >> +bool init_domheap_mappings(unsigned int cpu);
> >
> > I wonder if we can make this function "__init" as IIRC this function is only
> > used at Xen boot time, but since the original init_domheap_mappings()
> > is not "__init" anyway so this is not a strong argument.
>
> While this is not yet supported on Xen on Arm, CPUs can be
> onlined/offlined at runtime. So you want to keep init_domheap_mappings()
> around.
This is a very good point. I agree the pCPU online/offline is affected by the
"__init" so leaving the function without the "__init" like what we are doing
now is a good idea.
>
> We could consider to provide a new attribute that will be match __init
> if hotplug is supported otherwirse it would be a NOP. But I don't think
> this is related to this series (most of the function used for bringup
> are not in __init).
Agreed.
>
> >> +static inline bool init_domheap_mappings(unsigned int cpu)
> >
> > (and also here)
> >
> > Either you agree with above "__init" comment or not:
> > Reviewed-by: Henry Wang <Henry.Wang@xxxxxxx>
>
> Thanks!
No problem. To avoid confusion, my reviewed-by tag still holds.
Kind regards,
Henry
>
> Cheers,
>
> --
> Julien Grall
|
