From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751418AbdE3JLZ (ORCPT ); Tue, 30 May 2017 05:11:25 -0400 Received: from ozlabs.org ([103.22.144.67]:60003 "EHLO ozlabs.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750929AbdE3JLX (ORCPT ); Tue, 30 May 2017 05:11:23 -0400 X-powerpc-patch-notification: thanks X-powerpc-patch-commit: a3f952df3c6d205fe3b1e0e4848d3c3db4a28ef0 In-Reply-To: <20170512035810.15070-1-andrew@aj.id.au> To: Andrew Jeffery , linuxppc-dev@lists.ozlabs.org From: Michael Ellerman Cc: Andrew Jeffery , linux-kernel@vger.kernel.org, npiggin@gmail.com, paulus@samba.org, anton@samba.org Subject: Re: powerpc: Tweak copy selection parameter in __copy_tofrom_user_power7() Message-Id: <3wcSX91fQYz9s78@ozlabs.org> Date: Tue, 30 May 2017 19:11:21 +1000 (AEST) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 2017-05-12 at 03:58:10 UTC, Andrew Jeffery wrote: > Experiments with the netperf benchmark indicated that the size selecting > VMX-based copies in __copy_tofrom_user_power7() was suboptimal on POWER8. > Measurements showed that parity was in the neighbourhood of 3328 bytes, > rather than greater than 4096. The change gives a 1.5-2.0% improvement in > performance for 4096-byte buffers, reducing the relative time spent in > __copy_tofrom_user_power7() from approximately 7% to approximately 5% in > the TCP_RR benchmark. > > Signed-off-by: Andrew Jeffery > Acked-by: Anton Blanchard Applied to powerpc next, thanks. https://git.kernel.org/powerpc/c/a3f952df3c6d205fe3b1e0e4848d3c cheers