mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: Yazen Ghannam <yazen.ghannam@amd.com>
To: Thomas Gleixner <tglx@linutronix.de>
Cc: LKML <linux-kernel@vger.kernel.org>, <x86@kernel.org>, <bp@suse.de>
Subject: Re: [PATCH] x86/AMD: Fix LLC ID for AMD Fam17h systems
Date: Thu, 27 Oct 2016 09:58:51 -0400	[thread overview]
Message-ID: <b2f643aa-d161-0dbc-500c-d86426c85170@amd.com> (raw)
In-Reply-To: <alpine.DEB.2.20.1610262134130.5013@nanos>

>> +			/*
>> +			 * LLC is at the Core Complex level.
>> +			 * Core Complex Id is ApicId[3].
>> +			 */
>> +			else if (c->x86 == 0x17)
>> +				per_cpu(cpu_llc_id, cpu) = c->initial_apicid >> 3;
> 
> This whole if/else block lacks curly braces. See:
> 
>   https://marc.info/?l=linux-kernel&m=147351236615103
> 

Okay, understood.

>> -	/*
>> -	 * Fix percpu cpu_llc_id here as LLC topology is different
>> -	 * for Fam17h systems.
>> -	 */
>> -	 if (c->x86 != 0x17 || !cpuid_edx(0x80000006))
>> -		return;
>> -
>> -	socket_id	= (c->apicid >> bits) - 1;
>> -	core_complex_id	= (c->apicid & ((1 << bits) - 1)) >> 3;
>> -
>> -	per_cpu(cpu_llc_id, cpu) = (socket_id << 3) | core_complex_id;
> 
> So if I've read the patch correctly then the trivial fix for fam17h would
> have been:
> 
>> +	per_cpu(cpu_llc_id, cpu) = c->initial_apicid >> 3;
> 
> Right?
> 

Right.

> And this one liner wants to be a seperate patch with a proper
> explanation. And that simple hunk can be tagged for stable.
> 

Okay, I'll make it a separate patch. It still wouldn't be a one-liner
because then socket_id and core_complex_id would be left unused and
should be removed.

> The rest of the patch is cleanup and improvement and want's to be seperated
> out and explained proper.
> 

Okay, will do.

Thanks,
Yazen

      reply	other threads:[~2016-10-27 14:14 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-10-26 15:42 Yazen Ghannam
2016-10-26 20:00 ` Thomas Gleixner
2016-10-27 13:58   ` Yazen Ghannam [this message]

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=b2f643aa-d161-0dbc-500c-d86426c85170@amd.com \
    --to=yazen.ghannam@amd.com \
    --cc=bp@suse.de \
    --cc=linux-kernel@vger.kernel.org \
    --cc=tglx@linutronix.de \
    --cc=x86@kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox

all inboxes | Powered by JetHome®