From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from na01-bl2-obe.outbound.protection.outlook.com (mail-bl2lp0207.outbound.protection.outlook.com [207.46.163.207]) (using TLSv1 with cipher AES128-SHA (128/128 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 33E201A0055 for ; Mon, 2 Jun 2014 22:48:43 +1000 (EST) Message-ID: <538C7297.4040307@freescale.com> Date: Mon, 2 Jun 2014 15:48:23 +0300 From: Tudor Laurentiu MIME-Version: 1.0 To: Scott Wood Subject: Re: [PATCH v2] powerpc/booke64: wrap tlb lock and search in htw miss with FTR_SMT References: <1401489946-12935-1-git-send-email-scottwood@freescale.com> In-Reply-To: <1401489946-12935-1-git-send-email-scottwood@freescale.com> Content-Type: text/plain; charset="ISO-8859-1"; format=flowed Cc: Laurentiu Tudor , linuxppc-dev@lists.ozlabs.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On 05/31/2014 01:45 AM, Scott Wood wrote: > From: Laurentiu Tudor > > Virtualized environments may expose a e6500 dual-threaded core > as two single-threaded e6500 cores. Take advantage of this > and get rid of the tlb lock and the trap-causing tlbsx in > the htw miss handler by guarding with CPU_FTR_SMT, as it's > already being done in the bolted tlb1 miss handler. > > As seen in the results below, measurements done with lmbench > random memory access latency test running under Freescale's > Embedded Hypervisor, there is a ~34% improvement. > > Memory latencies in nanoseconds - smaller is better > (WARNING - may not be correct, check graphs) > ---------------------------------------------------- > Host Mhz L1 $ L2 $ Main mem Rand mem > --------- --- ---- ---- -------- -------- > smt 1665 1.8020 13.2 83.0 1149.7 > nosmt 1665 1.8020 13.2 83.0 758.1 > > Signed-off-by: Laurentiu Tudor > Cc: Scott Wood > [scottwood@freescale.com: commit message tweak] > Signed-off-by: Scott Wood > --- > v2: > - s/expose/may expose/ in commit message > - rebased onto my patch queue to resolve conflict Thanks! > - resent since the original didn't make it to the list archives > or patchwork. The only thing i can think of is that maybe i've misspelled the mailing list address ... --- Best Regards, Laurentiu