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Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Kaitao Cheng Content-Transfer-Encoding: quoted-printable Message-Id: <66E340E5-B2D2-4DB9-AE01-4F98C3182B06@linux.dev> References: <20261028121129.39916-1-kaitao.cheng@linux.dev> To: Kaitao Cheng X-Mailer: Apple Mail (2.3901.100.1.1.12) X-Rspamd-Server: rspam11 X-Rspamd-Queue-Id: BDB7F180009 X-Stat-Signature: ei7mdepesn5xcnxc87y66zyejusopgm9 X-Rspam-User: X-Spam-Status: No, score=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_PASS, SPF_PASS autolearn=ham autolearn_force=no version=4.0.1 X-HE-Tag: 1793192759-537033 X-HE-Meta: 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 4Uo1CRh5 bomtvc1SKYQdegbGOwyY1kBqAo7fLZuWbkJTotLI7X/Y9n+lKeClFFSacm/J4FLnZ+05g8UJ/pbBTMRf6jY9wldBhLb0MyNxZi6WUzwKoon2eq3qeECA0r6gZWijAmX5Wwvdf4dcsKtsW0WjzzxrlHGBvyLCCcMnmCcWELlLZNyCpB9/j4TaVqDSeM1C2IqpEureVklYB8dQB6ZbJttG7p2Q1CPeSZ9f4KbsJ3v7DFpCmhw9JKC0QTS6kFZ/5U47t6bE7byUgkMgKd2c= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 > On Oct 28, 2026, at 20:11, Kaitao Cheng = wrote: >=20 > From: Kaitao Cheng >=20 > sparse_init() is called only once during boot, and the vmemmap = alignment > check is outside any loop, so VM_WARN_ON_ONCE() provides no benefit = over > VM_WARN_ON() here. Yes. >=20 > Use VM_WARN_ON() and fold compound_info_has_mask() into its condition, > preserving short-circuit evaluation. >=20 > Signed-off-by: Kaitao Cheng > --- > mm/sparse.c | 6 ++---- > 1 file changed, 2 insertions(+), 4 deletions(-) >=20 > diff --git a/mm/sparse.c b/mm/sparse.c > index 6acb628c8a73..248bee2d39b9 100644 > --- a/mm/sparse.c > +++ b/mm/sparse.c > @@ -277,10 +277,8 @@ static void __init sparse_metadata_init(void) > */ > void __init sparse_init(void) > { > - if (compound_info_has_mask()) { > - VM_WARN_ON_ONCE(!IS_ALIGNED((unsigned long) = pfn_to_page(0), > - MAX_FOLIO_VMEMMAP_ALIGN)); > - } > + VM_WARN_ON(compound_info_has_mask() && !IS_ALIGNED( We usually don't end with "(=E2=80=9C. At least I rarely see that in the = existing code. We can break the line after &&. Thanks, Muchun > + (unsigned long)pfn_to_page(0), = MAX_FOLIO_VMEMMAP_ALIGN)); >=20 > sparse_metadata_init(); > sparse_init_subsection_map(); > --=20 > 2.53.0 >=20