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charset=us-ascii Content-Disposition: inline In-Reply-To: <37374089-895f-4c6f-a2f5-33859eb02b13@redhat.com> X-Rspamd-Queue-Id: D11F0A0018 X-Rspam-User: X-Rspamd-Server: rspam03 X-Stat-Signature: 9xrs5gfbhwhj1d546xnib7qmie7syafy X-HE-Tag: 1714601174-710203 X-HE-Meta: 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 nf0SmCc+ YVg64snOj7lINokyHnciWel5sVgcqHO5ZeZWibRuR1C7bc/O3frK/3qhnEhj93BeHGMIcprXsStCJVg/TpBQE3MoOVED3W71GFFODr18oM+Sho5czCVBTlxWFbhS+3sJuT9jtUxnQZODyRn8pUzCmjV8rRmsfxEnDjoeCdQld9EAdHMtsooMz7BFqCpQ1Z+rI3Dohyj+a0SgVyyIQPIbXRRn6Cn/wnShf3E1YWAZP6UgNm7eR/UaGr41bUWIlO1ZD8AdYCAOIyZFnRt0Zv+CCxXxIqOjv/OAR7FiCeM59k+jgDMMTK3EcQV1CcbsuEELCfP9j5DBzRHcLEyBPnBGF4iDNf7meSUHqcYKWA0SrpMAUAqvrv01JWfdHrQzP44/BxqOo7kph8ZgESoOmnPF8v0Dx5A1DQ4v84YlI 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 Thu, Apr 25, 2024 at 11:40:48AM +0200, David Hildenbrand wrote: > On 25.04.24 00:57, Luis Chamberlain wrote: > > We should check as early as possible if we should bail due to writeback > > or truncation. This will allow us to add further sanity checks earlier > > as well. > > > > This introduces no functional changes. > > > > Signed-off-by: Luis Chamberlain > > --- > > mm/huge_memory.c | 23 +++++++++++------------ > > 1 file changed, 11 insertions(+), 12 deletions(-) > > > > While working on min order support for LBS this came up as an improvement > > as we can check for the min order early earlier, so this sets the stage > > up for that. > > > > diff --git a/mm/huge_memory.c b/mm/huge_memory.c > > index 86a8c7b3b8dc..32c701821e0d 100644 > > --- a/mm/huge_memory.c > > +++ b/mm/huge_memory.c > > @@ -3055,8 +3055,17 @@ int split_huge_page_to_list_to_order(struct page *page, struct list_head *list, > > if (new_order >= folio_order(folio)) > > return -EINVAL; > > - /* Cannot split anonymous THP to order-1 */ > > - if (new_order == 1 && folio_test_anon(folio)) { > > + if (folio_test_writeback(folio)) > > + return -EBUSY; > > + > > Why earlier than basic input parameter checks (new_order? > > Sorry, but I don't see the reason for that change. It's all happening > extremely early, what are we concerned about? > > It's likely better to send that patch with the actual patch "to add further > sanity checks earlier as well", and why they have to be that early. It's a clear eye-sore when we add min order, I'll leave the eyesores for others. It can wait. Luis