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=-3.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 5F3FEC2D0E4 for ; Mon, 23 Nov 2020 17:05:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1666E206E3 for ; Mon, 23 Nov 2020 17:05:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730535AbgKWRFO convert rfc822-to-8bit (ORCPT ); Mon, 23 Nov 2020 12:05:14 -0500 Received: from eu-smtp-delivery-151.mimecast.com ([185.58.86.151]:49795 "EHLO eu-smtp-delivery-151.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729482AbgKWRFN (ORCPT ); Mon, 23 Nov 2020 12:05:13 -0500 Received: from AcuMS.aculab.com (156.67.243.126 [156.67.243.126]) (Using TLS) by relay.mimecast.com with ESMTP id uk-mta-221-bItNLEhdNW-xmw5Eq5Xq4Q-1; Mon, 23 Nov 2020 17:05:09 +0000 X-MC-Unique: bItNLEhdNW-xmw5Eq5Xq4Q-1 Received: from AcuMS.Aculab.com (fd9f:af1c:a25b:0:43c:695e:880f:8750) by AcuMS.aculab.com (fd9f:af1c:a25b:0:43c:695e:880f:8750) with Microsoft SMTP Server (TLS) id 15.0.1347.2; Mon, 23 Nov 2020 17:05:08 +0000 Received: from AcuMS.Aculab.com ([fe80::43c:695e:880f:8750]) by AcuMS.aculab.com ([fe80::43c:695e:880f:8750%12]) with mapi id 15.00.1347.000; Mon, 23 Nov 2020 17:05:08 +0000 From: David Laight To: 'Sahitya Tummala' , Jaegeuk Kim , Chao Yu , "linux-f2fs-devel@lists.sourceforge.net" CC: "linux-kernel@vger.kernel.org" Subject: RE: [PATCH] f2fs: change to use rwsem for cp_mutex Thread-Topic: [PATCH] f2fs: change to use rwsem for cp_mutex Thread-Index: AQHWwVm8Sokw4eOdHU6M1bsTH5HkTqnV8p0Q Date: Mon, 23 Nov 2020 17:05:08 +0000 Message-ID: <7f5213fb9b334d1290f019ab8ed6ee71@AcuMS.aculab.com> References: <1606109312-1944-1-git-send-email-stummala@codeaurora.org> In-Reply-To: <1606109312-1944-1-git-send-email-stummala@codeaurora.org> Accept-Language: en-GB, en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ms-exchange-transport-fromentityheader: Hosted x-originating-ip: [10.202.205.107] MIME-Version: 1.0 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=C51A453 smtp.mailfrom=david.laight@aculab.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: aculab.com Content-Language: en-US Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Sahitya Tummala > Sent: 23 November 2020 05:29 > > Use rwsem to ensure serialization of the callers and to avoid > starvation of high priority tasks, when the system is under > heavy IO workload. I can't see any read lock requests. So why the change? David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)