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]) by smtp.lore.kernel.org (Postfix) with ESMTP id 782CEC3600C for ; Thu, 3 Apr 2025 20:47:39 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 8BB5B280006; Thu, 3 Apr 2025 16:47:37 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 81D14280001; Thu, 3 Apr 2025 16:47:37 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 70B6B280006; Thu, 3 Apr 2025 16:47:37 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0016.hostedemail.com [216.40.44.16]) by kanga.kvack.org (Postfix) with ESMTP id 50F61280001 for ; Thu, 3 Apr 2025 16:47:37 -0400 (EDT) Received: from smtpin20.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay04.hostedemail.com (Postfix) with ESMTP id 476011A059F for ; 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charset=us-ascii Content-Disposition: inline In-Reply-To: <20250304150444.3788920-6-ryan.roberts@arm.com> X-Rspam-User: X-Rspamd-Server: rspam10 X-Rspamd-Queue-Id: 9FF8F20010 X-Stat-Signature: awe6u9qx8ruzws58ssbdd6awhjhd54o8 X-HE-Tag: 1743713256-781830 X-HE-Meta: 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 wfd+P520 CrJd+i0sAVEtZABet9HBJofkiVIDgp0u1N8mkLDgWTFkGdAadp2xnZDVTkMlLnbwEpnjNtF85ypghU/k85mRwLDiM5rMd+E75wGV6zRRyDoERmQusuTGEbR+bmYBTGt80r9Eg8tATnMm+fHzHNUxgIBk1vUeFOhsemaERc3gLWiSVvKf5nhaJi5pgsE0PmqXfr29AOG5fxPnjOUgVMOHcFKVvnaiw2KX6pAFjlgfkglEyiSjtgFtz92mA4VvlCp6NO8UmFqrz1+ZD2M34E3oL4M817uMCVN1Bawi71Sf3Sumyc6dJHTGW76/qck7SptHrFmZMRIH0umXJkXivAOFBywa+H9lRcnwsNIVGx7xEHBGhSPNNDKjr+gTsXm+B+xsxZL9CcwM4TfF3topq82GZ2xzvM3LilB/HAAYmb3V4QDJrq4OeXl/KzwNZqOq73Kt2hnELhQ5EAet2xX4= 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 Tue, Mar 04, 2025 at 03:04:35PM +0000, Ryan Roberts wrote: > Refactor the huge_pte helpers to use the new common set_ptes_anysz() and > ptep_get_and_clear_anysz() APIs. Nitpick: maybe add underscores to this new API to suggest it's private. Up to you. > This provides 2 benefits; First, when page_table_check=on, hugetlb is > now properly/fully checked. Previously only the first page of a hugetlb > folio was checked. Second, instead of having to call __set_ptes(nr=1) > for each pte in a loop, the whole contiguous batch can now be set in one > go, which enables some efficiencies and cleans up the code. > > One detail to note is that huge_ptep_clear_flush() was previously > calling ptep_clear_flush() for a non-contiguous pte (i.e. a pud or pmd > block mapping). This has a couple of disadvantages; first > ptep_clear_flush() calls ptep_get_and_clear() which transparently > handles contpte. Given we only call for non-contiguous ptes, it would be > safe, but a waste of effort. It's preferable to go straight to the layer > below. However, more problematic is that ptep_get_and_clear() is for > PAGE_SIZE entries so it calls page_table_check_pte_clear() and would not > clear the whole hugetlb folio. So let's stop special-casing the non-cont > case and just rely on get_clear_contig_flush() to do the right thing for > non-cont entries. > > Signed-off-by: Ryan Roberts Reviewed-by: Catalin Marinas