Date: Sat, 23 Mar 2013 17:25:58 +0100
From: Borislav Petkov <bp@alien8.de>
To: Andi Kleen <andi@firstfloor.org>, linux-kernel@vger.kernel.org,
        torvalds@linux-foundation.org, akpm@linux-foundation.org,
        x86@kernel.org, Andi Kleen <ak@linux.intel.com>
Subject: Re: [PATCH 12/29] x86, tsx: Add a per thread transaction disable
 count
Message-ID: <20130323162558.GD10811@pd.tnic>
Mail-Followup-To: Borislav Petkov <bp@alien8.de>,
	Andi Kleen <andi@firstfloor.org>, linux-kernel@vger.kernel.org,
	torvalds@linux-foundation.org, akpm@linux-foundation.org,
	x86@kernel.org, Andi Kleen <ak@linux.intel.com>
References: <1364001923-10796-1-git-send-email-andi@firstfloor.org>
 <1364001923-10796-13-git-send-email-andi@firstfloor.org>
 <20130323115115.GA10821@pd.tnic>
 <20130323135156.GJ20853@two.firstfloor.org>
 <20130323155256.GB10811@pd.tnic>
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Disposition: inline
In-Reply-To: <20130323155256.GB10811@pd.tnic>
User-Agent: Mutt/1.5.21 (2010-09-15)
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 816
Lines: 22

On Sat, Mar 23, 2013 at 04:52:56PM +0100, Borislav Petkov wrote:
> And wow, the XOR is *actually* faster. That's whopping three cycles on
> AMD. Similar observation on SNB.

Ok, correction: I was looking at the wrong row in the table. The XOR
version with an immediate and mem access is actually as fast as the
INC/DEC mem versions: 4 cycles on AMD F10h and 6 on SNB, according to
the docs. I should've realized that there's still a mem access there...

Anyway, the rest stands.

-- 
Regards/Gruss,
    Boris.

Sent from a fat crate under my desk. Formatting is fine.
--
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/