Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::3:3 as permitted sender) client-ip=2620:137:e000::3:3;
Date:   Tue, 19 Sep 2023 12:37:35 -0400
From:   Gregory Price <gregory.price@memverge.com>
To:     Thomas Gleixner <tglx@linutronix.de>
Cc:     Gregory Price <gourry.memverge@gmail.com>,
        linux-mm@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-arch@vger.kernel.org, linux-api@vger.kernel.org,
        linux-cxl@vger.kernel.org, luto@kernel.org, mingo@redhat.com,
        bp@alien8.de, dave.hansen@linux.intel.com, hpa@zytor.com,
        arnd@arndb.de, akpm@linux-foundation.org, x86@kernel.org
Subject: Re: [RFC PATCH 3/3] mm/migrate: Create move_phys_pages syscall
Message-ID: <ZQnOTzm6l8RSQquH@memverge.com>
References: <20230907075453.350554-1-gregory.price@memverge.com>
 <20230907075453.350554-4-gregory.price@memverge.com>
 <877conxbhw.ffs@tglx>
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <877conxbhw.ffs@tglx>
MIME-Version: 1.0
X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1
X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?mXBKVqyrk0gbNnQNNLzmL8uesIyqHeRvK/ypXjWsAUX1N6UCh9/LpAvhPbh5?=
 =?us-ascii?Q?rNI032rq7XWJ015crWya3TNxunqzBRkJHV6mhSQoaONveSCgHG42w4VwxgHk?=
 =?us-ascii?Q?RF+tbUv932VCmY7dF1NnDwjUTCfdlOUzXFdW6Z4hFaWFKYTDMJxjD+gjABv7?=
 =?us-ascii?Q?vKEEC4LJG2a+9qpp7i2kCJyVCS6zk5mjJrDy1TzwG6V5QXz/kuLj3C0YNuQ1?=
 =?us-ascii?Q?TomPK1+oxnJadwTa1GXiWEJx0b43CLmgm4prMFItz6qm+d0sPaeOqy/9cMJY?=
 =?us-ascii?Q?snxJpb23MzinaRUOqEQZkGKhYW2p06CflBVHFcLxzReVraSlp1LF+rDcjD2k?=
 =?us-ascii?Q?DPfFF1WbTRGwghcja2HX4YijoJI99zP+U2TJLGPSCkwFfTB4juPzycEkZWrs?=
 =?us-ascii?Q?rYh98tssu2i3lGwI30OISbHWScOdedDEciqgLU7R3TQnhrOfHxi6vFaSGK0X?=
 =?us-ascii?Q?VgvbUjPwAAiw5O3K6SStRbAa4W4iqCLs/eIR76m9R3jk4djKPr4iNgg0l4ro?=
 =?us-ascii?Q?YCAqmUfHij1z25ZSgpGM6JFMAau1U9HsZEEm5+zlz5SWVxSqNuOF1LTcr64b?=
 =?us-ascii?Q?43szTRlb/YWaik7j/aguycHj041wPR/gBwgagUjNjKojyo1xOYvfpxgB/v2M?=
 =?us-ascii?Q?EKjNljISoMKDVlVeT3zZGhE0zpk8qYPOnGW5rRTYhXe57feyHAU7AMorIX9I?=
 =?us-ascii?Q?F6WUkSiFl3VVk7+TY5RI/5uCamTawEy7ZNXWMgSkbwPc8FT/4sf716yaa/Eq?=
 =?us-ascii?Q?UmZjiU5pZiMUAAQEG7KTrV9cxJoi5KrOQhPD/9T0AE9FgdiWsg/dnkETh9Z7?=
 =?us-ascii?Q?SQ4/Fntzh5XuV8SYdKCfhKB6yoKInhG6QovXxbU9ALLHc1jibILm8Ul/U7RT?=
 =?us-ascii?Q?sKSh1KG+w7XL91cflZ8lR4rKEA0nIDjUuV4j1HmBiF6SeJHBKHcX7FdCzKvK?=
 =?us-ascii?Q?RBfPLiopx485JrDN8ThQ2MoDx0PhSd4fQ2n0In8fOJ3P/zB17hyNJGwCX5ti?=
 =?us-ascii?Q?zdhjlNUAX/1ST+9ujoiqyLzn9Uk2vl5+dTQAKl7GMSZOEF8fHZkYaSPuafVP?=
 =?us-ascii?Q?TEZODal9GNtKSgsc8fcVymDKN6fkCYK3/plVkXElgr3jGaEk929Z0bKOz1pZ?=
 =?us-ascii?Q?UScabAAx8rv6POLI7aidJt7kea8H8GzBl5pz+GHPMCz9hQe2+aI1TMNrJA0b?=
 =?us-ascii?Q?kD02GNlJ6tVfMiymN0uMkLXPzFxiPQG/tY3i3nfinV1qteyRsYk0qgzxqW07?=
 =?us-ascii?Q?LMr88N2G/70sa7zFRvaJ5ZpTf2HY9QF0K5hEtlLYCqzDdbqzcveIOdaAdch7?=
 =?us-ascii?Q?lknOoxY0coyvgcErVw/548rz52WC1QGHnsG2akj+hUMr27uCXxRwx7L9Nof5?=
 =?us-ascii?Q?o5DVZdeV+PfCCmhBeSLd8cML1CkmaEDFNrWjLJlXKNwezu8d5vA05TAknVqi?=
 =?us-ascii?Q?AUAH42G3UsbioF1h5D+jGQagYBWxWeexT+qkZkzQMqj6QgS0ypNe0eUefJkZ?=
 =?us-ascii?Q?/9AMLuA56NWy0FB/6VAktTY4X9uwVg4EXSsfCZ0+D70F5ZMugyRJPJuwL4G3?=
 =?us-ascii?Q?abvk4PMeLm6MNHbzzLlz3L6vODTin5TFPbSydxBcWkN0oJ1AOfI36I2zZ1/E?=
 =?us-ascii?Q?mg=3D=3D?=
X-OriginatorOrg: memverge.com
X-MS-Exchange-CrossTenant-Network-Message-Id: 4bfd29df-0e95-4196-6065-08dbb92ebd05
X-MS-Exchange-CrossTenant-AuthSource: SJ0PR17MB5512.namprd17.prod.outlook.com
X-MS-Exchange-CrossTenant-AuthAs: Internal
X-MS-Exchange-CrossTenant-OriginalArrivalTime: 19 Sep 2023 16:37:39.5119
 (UTC)
X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted
X-MS-Exchange-CrossTenant-Id: 5c90cb59-37e7-4c81-9c07-00473d5fb682
X-MS-Exchange-CrossTenant-MailboxType: HOSTED
X-MS-Exchange-CrossTenant-UserPrincipalName: nFntczb89G0snSJ0KqRxTdBWtvd9i7geGV/ihVR2NnHMy2kMKfW7VcK+Zf7wLqpZf6FHjWDmf9a2EktJBea9a/un0GhMxAZC3d7BdMabcqc=
X-MS-Exchange-Transport-CrossTenantHeadersStamped: MW4PR17MB4857
X-Spam-Status: No, score=-0.9 required=5.0 tests=DKIM_SIGNED,DKIM_VALID,
	DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,
	SPF_HELO_NONE,SPF_PASS autolearn=unavailable autolearn_force=no
	version=3.4.6
X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lipwig.vger.email
Precedence: bulk
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org
X-Greylist: Sender passed SPF test, not delayed by milter-greylist-4.6.4 (lipwig.vger.email [0.0.0.0]); Tue, 19 Sep 2023 09:37:53 -0700 (PDT)

On Tue, Sep 19, 2023 at 02:17:15AM +0200, Thomas Gleixner wrote:
> On Thu, Sep 07 2023 at 03:54, Gregory Price wrote:
> > +	/* All tasks mapping each page is checked in phys_page_migratable */
> > +	nodes_setall(target_nodes);
> 
> How is the comment related to nodes_setall() and why is nodes_setall()
> unconditional when target_nodes is only used in the @nodes != NULL case?
> 

Short follow up, sorry for the spam.  I realized there is a better way
to do this by simply bypassing the task node check in do_pages_moves if
the mm_struct is NULL.  This removes the need for this struct
all-together.

Will simplify down for a v2 and add comments to do_pages_move
accordingly.

~Gregory