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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 33F35CA1002 for ; Thu, 4 Sep 2025 17:00:31 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 9211F8E0010; Thu, 4 Sep 2025 13:00:30 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 8F86B8E0001; Thu, 4 Sep 2025 13:00:30 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 835E98E0010; Thu, 4 Sep 2025 13:00:30 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0013.hostedemail.com [216.40.44.13]) by kanga.kvack.org (Postfix) with ESMTP id 6F3478E0001 for ; Thu, 4 Sep 2025 13:00:30 -0400 (EDT) Received: from smtpin30.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay05.hostedemail.com (Postfix) with ESMTP id 1F21958693 for ; 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charset=us-ascii Content-Disposition: inline In-Reply-To: <20250829115250.2395585-7-ryan.roberts@arm.com> X-Rspam-User: X-Rspamd-Server: rspam11 X-Rspamd-Queue-Id: 4767780014 X-Stat-Signature: z7fi8p7h8e4t9uuyxwkewatcdhn4c334 X-HE-Tag: 1757005228-833011 X-HE-Meta: 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 WDrzKLav sE6jbCFzGhQ9m33F6DWk0ij8KKzMPLIj2PvDeKN4lv56diWpOmwcavZUOjFQLpZ6d18lHKXDk4hU/52i4n+zX4YuQp/fJM2lClSPyy3VcT5/qQeAPhyUucocrb1JLijdKorw1JtP2KW8MkEJS9uK9NvsYZDdWGcvEvPPJKY3R7HgoCGNwRGub/2V1xurpegnWvvBPq61jM6+zON8lds9/RZFl3Xh55/UZ3r1ni54B8GdEkfihCeMFZ3MbuT+1MSarrwqSNFYPdffs0XWLus4NGeAho28tTNrJMYGyWegDljh7jWdv9PNALygCt40RtLy571NzwOdXr9vtH0QKOta+lcXapUdFDy924qFTljEPaVJr7y1zaLI9U9nPoLIXQpDowpynFdDj8mHfhLRjXPrnkhqoFwBO//gItdbr6IwpTvsuifscsKCiUVlc0FWwCb4zy+lQPDG6Vq0qcICCPf8CahhCtm9qtmwem6Tv X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Fri, Aug 29, 2025 at 12:52:47PM +0100, Ryan Roberts wrote: > When splitting kernel leaf mappings, either via > split_kernel_leaf_mapping_locked() or linear_map_split_to_ptes(), > previously a leaf mapping was always split to the next size down. e.g. > pud -> contpmd -> pmd -> contpte -> pte. But for > linear_map_split_to_ptes() we can avoid the contpmd and contpte states > because we know we want to split all the way down to ptes. > > This avoids visiting all the ptes in a table if it was created by > splitting a pmd, which is noticible on systems with a lot of memory. > > Signed-off-by: Ryan Roberts Reviewed-by: Catalin Marinas