Received: by 2002:a05:6a10:f347:0:0:0:0 with SMTP id d7csp999884pxu; Mon, 23 Nov 2020 09:09:29 -0800 (PST) X-Google-Smtp-Source: ABdhPJysxgnNTKXB5CR8Rus+0alM/vcdr7IwdPKYLtbTyjP6jsviey6mA3QiQcvEdnNoT3+y2g0z X-Received: by 2002:a17:906:6d8e:: with SMTP id h14mr540348ejt.522.1606151368867; Mon, 23 Nov 2020 09:09:28 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1606151368; cv=none; d=google.com; s=arc-20160816; b=Cg5NstREwyEfl075GwchGNoDactVchMfa7knvrbQx3oB+dsJrWnXJkfMUoqI09KJ+T Zs4fZpG7W4Cb5BQh+dTqBpTnuOFuovxxZf91cs1IQZ8T3SR1UzqvbbRZpXdYhVuBX1oO kupGv/UUf2m1AXEv633PpMGvf6x0w3ewpTFjILn+sA/4dWFejXnVp3JpzcobJRx6skd2 iPTO/ZgdAg7pU/h9v1E4Bl4v069kaZE0lEQ85DaqkNO/2FCAP8cavJKqSXJSjW63/XJn dKSZQSKqjU0jPtiVD4xVVQ13kR1VRAbM1yFtNwbQ+Qj1S6o6Z1tgwz6gH+b73Abqh7hL 02Ew== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:content-language :mime-version:accept-language:in-reply-to:references:message-id:date :thread-index:thread-topic:subject:cc:to:from; bh=lzxEHe5h9+C/LtkffOaISHrNR4cnYOZwIFNo0CyVc7A=; b=CjpGL6hI1klCl37ioKwSc50Bcx6WQSITg6m4EvOuAtATd4cr7J5M5HLPwDxY701xvf iTTuFaGvJzZRoWILqcgb3kMzeBiNrhYKW1Nag3sz8kKc+mMkvx+vLlJk9c2w9J/R2zv1 igg5Kct6t1qvevQwJCWLwJyukUmyFNT8BNAgHTh1WfFEhTqkK6HXSnCQXSOr+kUBYVjY IZ30sy9dHwINOcFAV7faZq6/DdJvdwtYetFaBeJTaNh6mrHKGUtVFJ/D6cGEWCP4XF2k iB+89o1PQDdZYtE90J/iE1YH0uR6GhFlYqP2U50MNfWTrahyW45dUWq8hz9Lw6BW/+Re hxvA== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=aculab.com Return-Path: Received: from vger.kernel.org (vger.kernel.org. [23.128.96.18]) by mx.google.com with ESMTP id i12si3900304ejb.749.2020.11.23.09.09.05; Mon, 23 Nov 2020 09:09:28 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=aculab.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729370AbgKWRFN convert rfc822-to-8bit (ORCPT + 99 others); Mon, 23 Nov 2020 12:05:13 -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)