Subject: Re: [RFC Part1 PATCH v3 09/17] resource: Consolidate resource walking
 code
From: Tom Lendacky <thomas.lendacky@amd.com>
To: Borislav Petkov <bp@suse.de>, Brijesh Singh <brijesh.singh@amd.com>
Cc: linux-kernel@vger.kernel.org, x86@kernel.org,
        linux-efi@vger.kernel.org, linuxppc-dev@lists.ozlabs.org,
        kvm@vger.kernel.org, Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, "H . Peter Anvin" <hpa@zytor.com>,
        Andy Lutomirski <luto@kernel.org>, Tony Luck <tony.luck@intel.com>,
        Piotr Luc <piotr.luc@intel.com>, Fenghua Yu <fenghua.yu@intel.com>,
        Lu Baolu <baolu.lu@linux.intel.com>,
        Reza Arbab <arbab@linux.vnet.ibm.com>,
        David Howells <dhowells@redhat.com>,
        Matt Fleming <matt@codeblueprint.co.uk>,
        "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>,
        Laura Abbott <labbott@redhat.com>,
        Ard Biesheuvel <ard.biesheuvel@linaro.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Eric Biederman <ebiederm@xmission.com>,
        Benjamin Herrenschmidt <benh@kernel.crashing.org>,
        Paul Mackerras <paulus@samba.org>,
        Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>,
        Jonathan Corbet <corbet@lwn.net>, Dave Airlie <airlied@redhat.com>,
        Kees Cook <keescook@chromium.org>, Paolo Bonzini <pbonzini@redhat.com>,
        =?UTF-8?B?UmFkaW0gS3LEjW3DocWZ?= <rkrcmar@redhat.com>,
        Arnd Bergmann <arnd@arndb.de>, Tejun Heo <tj@kernel.org>,
        Christoph Lameter <cl@linux.com>
References: <20170724190757.11278-1-brijesh.singh@amd.com>
 <20170724190757.11278-10-brijesh.singh@amd.com>
 <20170728152342.GB11564@nazgul.tnic>
 <a31c9643-87a5-ae4a-25a5-9dae235f158d@amd.com>
Message-ID: <029b17ab-00c4-c845-d39f-1b3337e296b1@amd.com>
Date: Thu, 17 Aug 2017 14:03:30 -0500
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On 8/17/2017 1:55 PM, Tom Lendacky wrote:
> On 7/28/2017 10:23 AM, Borislav Petkov wrote:
>> On Mon, Jul 24, 2017 at 02:07:49PM -0500, Brijesh Singh wrote:
>>> From: Tom Lendacky <thomas.lendacky@amd.com>
>>>
>>> The walk_iomem_res_desc(), walk_system_ram_res() and 
>>> walk_system_ram_range()
>>> functions each have much of the same code.  Create a new function that
>>> consolidates the common code from these functions in one place to reduce
>>> the amount of duplicated code.
>>>
>>> Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
>>> Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
>>> ---
>>>   kernel/resource.c | 53 
>>> ++++++++++++++++++++++++++---------------------------
>>>   1 file changed, 26 insertions(+), 27 deletions(-)
>>>
>>> diff --git a/kernel/resource.c b/kernel/resource.c
>>> index 9b5f044..7b20b3e 100644
>>> --- a/kernel/resource.c
>>> +++ b/kernel/resource.c
>>> @@ -397,9 +397,30 @@ static int find_next_iomem_res(struct resource 
>>> *res, unsigned long desc,
>>>           res->start = p->start;
>>>       if (res->end > p->end)
>>>           res->end = p->end;
>>> +    res->desc = p->desc;
>>>       return 0;
>>
>> I must be going blind: where are we using that res->desc?
> 
> I think that was left-over from the initial consolidation work I was
> doing.  I'll remove it.

I spoke too soon...  I use it in a later patch as part of a callback.
But instead of putting it here, I'll add it to the patch that actually
needs it.

Thanks,
Tom

> 
>>
>>> +static int __walk_iomem_res_desc(struct resource *res, unsigned long 
>>> desc,
>>> +                 bool first_level_children_only,
>>
>> Btw, that variable name is insanely long.
> 
> I know, but I'm maintaining consistency with the name that was already
> present vs. changing it.
> 
>>
>> The rest looks ok to me, thanks for the cleanup!
> 
> Thanks,
> Tom
> 
>>