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[147.75.48.161]) by mx.google.com with ESMTPS id i11-20020a17090ad34b00b0029b9e5079d8si6657130pjx.117.2024.03.10.11.16.10 for (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 10 Mar 2024 11:16:11 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel+bounces-98290-linux.lists.archive=gmail.com@vger.kernel.org designates 147.75.48.161 as permitted sender) client-ip=147.75.48.161; Authentication-Results: mx.google.com; arc=fail (body hash mismatch); spf=pass (google.com: domain of linux-kernel+bounces-98290-linux.lists.archive=gmail.com@vger.kernel.org designates 147.75.48.161 as permitted sender) smtp.mailfrom="linux-kernel+bounces-98290-linux.lists.archive=gmail.com@vger.kernel.org"; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=aculab.com Received: from smtp.subspace.kernel.org (wormhole.subspace.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by sy.mirrors.kernel.org (Postfix) with ESMTPS id C02AEB20A67 for ; Sun, 10 Mar 2024 18:16:08 +0000 (UTC) Received: from localhost.localdomain (localhost.localdomain [127.0.0.1]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 4CAF039ADD; Sun, 10 Mar 2024 18:16:02 +0000 (UTC) Received: from eu-smtp-delivery-151.mimecast.com (eu-smtp-delivery-151.mimecast.com [185.58.86.151]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C3A723984A for ; Sun, 10 Mar 2024 18:15:59 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=185.58.86.151 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1710094561; cv=none; b=tmvcYIG+JNCUtYzpC8S63WxtG/pA7NFmRtfWIMuQq3gdOOmKBrWmwHnFh7BhF8RcogA/pugzJtTpW9jYHmMdEKRSrK4IiDe24ZNskJPgurOyWcptNLHipF2BT7wV0zL3QS255VJ74lxo53PgSpPmRIGBuw5xDh37yVO7VtQynok= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1710094561; c=relaxed/simple; bh=Qx07yZjSZ7SbcPOXqmK826JgccBle9qSUP1spG7BlnQ=; h=From:To:CC:Subject:Date:Message-ID:References:In-Reply-To: MIME-Version:Content-Type; b=NIdglsopqQz/cqtnkuHUSe1E2BH2Sb5Tu6RJdUooHmh6RAaLXUVgZU8mGL4a4V7zWbwtYYx5Rwc4wLg4KIdD7scrSRHwMZlRbGhVNfZn056sEnKqVxWdh/BVJo9OkDMpySlpt3dHGsSI18Ud8iv+784AmmYHS/erz60SN4xDvO8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=ACULAB.COM; spf=pass smtp.mailfrom=aculab.com; arc=none smtp.client-ip=185.58.86.151 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=ACULAB.COM Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=aculab.com Received: from AcuMS.aculab.com (156.67.243.121 [156.67.243.121]) by relay.mimecast.com with ESMTP with both STARTTLS and AUTH (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384) id uk-mta-287-zx9oxXdGOaq_m6L14ONI6A-1; Sun, 10 Mar 2024 18:15:56 +0000 X-MC-Unique: zx9oxXdGOaq_m6L14ONI6A-1 Received: from AcuMS.Aculab.com (10.202.163.4) by AcuMS.aculab.com (10.202.163.4) with Microsoft SMTP Server (TLS) id 15.0.1497.48; Sun, 10 Mar 2024 18:16:06 +0000 Received: from AcuMS.Aculab.com ([::1]) by AcuMS.aculab.com ([::1]) with mapi id 15.00.1497.048; Sun, 10 Mar 2024 18:16:06 +0000 From: David Laight To: 'Steven Rostedt' , "linux-kernel@vger.kernel.org" CC: Masami Hiramatsu , Mark Rutland , Mathieu Desnoyers , Andrew Morton Subject: RE: [for-linus][PATCH 0/3] tracing: Fixes for v6.8 Thread-Topic: [for-linus][PATCH 0/3] tracing: Fixes for v6.8 Thread-Index: AQHab/YPIm1nuew0EUiHLmodmjEdKrExTS0w Date: Sun, 10 Mar 2024 18:16:06 +0000 Message-ID: <550b6c44aa434b5b91e999a8d073527c@AcuMS.aculab.com> References: <20240306184244.754263547@goodmis.org> In-Reply-To: <20240306184244.754263547@goodmis.org> Accept-Language: en-GB, en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ms-exchange-transport-fromentityheader: Hosted Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: aculab.com Content-Language: en-US Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable .. > Another issue that was brought up is that the trace_seq buffer is > also based on PAGE_SIZE even though it is not tied to the architecture > limit like the ring buffer sub-buffer is. Having it be 64K * 2 is > simply just too big and wasting memory on systems with 64K page sizes. > It is now hardcoded to 8K which is what all other architectures with > 4K PAGE_SIZE has. Does Linux use a 2k PAGE_SIZE on any architectures? IIRC m68k hardware has a 2k page, but Linux might always pair them. A 2k page might (or might not) cause grief. =09David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1= PT, UK Registration No: 1397386 (Wales)