From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 528D6C433E0 for ; Thu, 11 Jun 2020 10:39:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3830B206C3 for ; Thu, 11 Jun 2020 10:39:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727095AbgFKKj4 (ORCPT ); Thu, 11 Jun 2020 06:39:56 -0400 Received: from mga02.intel.com ([134.134.136.20]:47919 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726864AbgFKKjw (ORCPT ); Thu, 11 Jun 2020 06:39:52 -0400 IronPort-SDR: rvW4FZpXds/zgrK11PAcerrWa3MUF6c5bAK1d9tW0D2laaa2B2GBHO4HBJ7ednGs8FQbgi4Uqq U3XXfluWVsjg== X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by orsmga101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 11 Jun 2020 03:39:51 -0700 IronPort-SDR: n1oDAK+8ZZRCo4XPJCfRE/6cleWAyxhiJPzudO4+U5xSV/Bp68ZuhzSbxXvQkATLEVN8eu6V0y T7NxhaoTxIKA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.73,499,1583222400"; d="scan'208";a="380349596" Received: from lahna.fi.intel.com (HELO lahna) ([10.237.72.163]) by fmsmga001.fm.intel.com with SMTP; 11 Jun 2020 03:39:48 -0700 Received: by lahna (sSMTP sendmail emulation); Thu, 11 Jun 2020 13:39:47 +0300 Date: Thu, 11 Jun 2020 13:39:47 +0300 From: Mika Westerberg To: Luis Alberto Herrera Cc: tudor.ambarus@microchip.com, Miquel Raynal , Richard Weinberger , Vignesh Raghavendra , Jethro Beekman , Boris Brezillon , linux-mtd@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] mtd: revert "spi-nor: intel: provide a range for poll_timout" Message-ID: <20200611103947.GC247495@lahna.fi.intel.com> References: <20200610224652.64336-1-luisalberto@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200610224652.64336-1-luisalberto@google.com> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jun 10, 2020 at 10:46:49PM +0000, Luis Alberto Herrera wrote: > This change reverts aba3a882a178: "mtd: spi-nor: intel: provide a range > for poll_timout". That change introduces a performance regression when > reading sequentially from flash. Logging calls to intel_spi_read without > this change we get: > > Start MTD read > [ 20.045527] intel_spi_read(from=1800000, len=400000) > [ 20.045527] intel_spi_read(from=1800000, len=400000) > [ 282.199274] intel_spi_read(from=1c00000, len=400000) > [ 282.199274] intel_spi_read(from=1c00000, len=400000) > [ 544.351528] intel_spi_read(from=2000000, len=400000) > [ 544.351528] intel_spi_read(from=2000000, len=400000) > End MTD read > > With this change: > > Start MTD read > [ 21.942922] intel_spi_read(from=1c00000, len=400000) > [ 21.942922] intel_spi_read(from=1c00000, len=400000) > [ 23.784058] intel_spi_read(from=2000000, len=400000) > [ 23.784058] intel_spi_read(from=2000000, len=400000) > [ 25.625006] intel_spi_read(from=2400000, len=400000) > [ 25.625006] intel_spi_read(from=2400000, len=400000) > End MTD read > > Signed-off-by: Luis Alberto Herrera Acked-by: Mika Westerberg