From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.16]) (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 DA0AF27B353 for ; Mon, 18 Aug 2025 16:42:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.175.65.16 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755535377; cv=none; b=h2esYAEDc9BGL1vhpx3w8lD62SUYjKfqdXCznRMj0GNeCfwV5ABn1TZKtWSywE584ds2hz4kYm2HDUq4L+jHT39XDRPY6FIWMinGnZTj72FbN4pygZ4AMTX/5YM4+f6uzVa9CtrQOAAKP7sXu8jx/MsFI2Qx789PjwxIcjSziIg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755535377; c=relaxed/simple; bh=FFRgUjm1Gro1I+69P/TMbAic2wfSm8DMVKGUgEm0vxw=; h=Message-ID:Subject:From:To:Cc:Date:In-Reply-To:References: Content-Type:MIME-Version; b=dzo2Xh9tQ4rStYWrALxg2F6OFsUwKi4Ns+9I5JcDmBoCoqyGt7op2A4eqFo5VeRLMsmeg3SAjD3L1M8UelmVkeWLgyRoNClxy2ChKfINqS44PMZPx48nLXSkmGuCVoijDmrC76dL+iw2ovyGvoxZl/eDK43SONDnnDiT1kJLMxA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com; spf=none smtp.mailfrom=linux.intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=maw53CTF; arc=none smtp.client-ip=198.175.65.16 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="maw53CTF" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1755535376; x=1787071376; h=message-id:subject:from:to:cc:date:in-reply-to: references:content-transfer-encoding:mime-version; bh=FFRgUjm1Gro1I+69P/TMbAic2wfSm8DMVKGUgEm0vxw=; b=maw53CTFmkrYF7Mg2LCtKnBqlqr8Sbb/RPP+EJm8zmWfSaT61XZZBXU4 uzUuM5YsNnH+h+v7ZK2E5iaxwGN9IGdPDYPcGPPUZyQ3xiomveY7MClfu 7sYS5OlRprSH/q6PfqA9/6d2YfZccjDsYHpsyBGjuDnECsNO8tiQD+I9G PG37JQjHebWFMh+uv5D9G4QDnzxsd31LStvFS4sLEbNDSsJIphrk85nxu dpvQV9IumKLY1V0UCPLJ+nXtr3dSoGLgIIGaSPz9Qqm3LeuTkE45XtypK 67Pv6n04/Bs0NVO+8EZFmYZxGBhnFsekTItkbygwPN7UcXvkI+TsUfWsA g==; X-CSE-ConnectionGUID: mckg41UmQzGsquXAUXM3Bw== X-CSE-MsgGUID: shb22CqcScCfa5D0N/GqtQ== X-IronPort-AV: E=McAfee;i="6800,10657,11526"; a="57913905" X-IronPort-AV: E=Sophos;i="6.17,300,1747724400"; d="scan'208";a="57913905" Received: from orviesa008.jf.intel.com ([10.64.159.148]) by orvoesa108.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 18 Aug 2025 09:42:55 -0700 X-CSE-ConnectionGUID: hg58vD3gT1C5B79/FUkiiQ== X-CSE-MsgGUID: wD+yurJLT02ZIM7X6sfNmA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.17,300,1747724400"; d="scan'208";a="167863384" Received: from abityuts-desk.ger.corp.intel.com (HELO [10.245.244.38]) ([10.245.244.38]) by orviesa008-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 18 Aug 2025 09:42:52 -0700 Message-ID: Subject: Re: [RFC PATCH 1/6] mm/mmu_notifier: Allow multiple struct mmu_interval_notifier passes From: Thomas =?ISO-8859-1?Q?Hellstr=F6m?= To: Jason Gunthorpe , Matthew Brost Cc: intel-xe@lists.freedesktop.org, Andrew Morton , Simona Vetter , Dave Airlie , dri-devel@lists.freedesktop.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Christian =?ISO-8859-1?Q?K=F6nig?= Date: Mon, 18 Aug 2025 18:42:36 +0200 In-Reply-To: <20250818163617.GI599331@ziepe.ca> References: <20250809135137.259427-1-thomas.hellstrom@linux.intel.com> <20250809135137.259427-2-thomas.hellstrom@linux.intel.com> <20250818160726.GH599331@ziepe.ca> <20250818163617.GI599331@ziepe.ca> Organization: Intel Sweden AB, Registration Number: 556189-6027 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.54.3 (3.54.3-1.fc41) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 On Mon, 2025-08-18 at 13:36 -0300, Jason Gunthorpe wrote: > On Mon, Aug 18, 2025 at 09:25:20AM -0700, Matthew Brost wrote: > > I think this choice makes sense: it allows embedding the wait state > > from > > the initial notifier call into the pass structure. Patch [6] shows > > this > > by attaching the issued TLB invalidation fences to the pass. Since > > a > > single notifier may be invoked multiple times with different ranges > > but > > the same seqno, >=20 > That should be explained, but also seems to be a bit of a different > issue.. >=20 > If the design is really to only have two passes and this linked list > is about retaining state then there should not be so much freedom to > have more passes. Actually the initial suggestion was two passes only. Then I thought I saw a use-case for even three passes and added the multi-pass thing, but I think it turned out we didn't have such a use-case. IMO we could restrict it to two-pass. Matthew, that should be completely OK for the SVM use-case, right? /Thomas >=20 > Jason