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Shutemov" , Luis Chamberlain , Matthew Wilcox , Vlastimil Babka , Yang Shi , Yin Fengwei , Yu Zhao , Zi Yan Subject: [PATCH] mm: alloc_anon_folio: avoid doing vma_thp_gfp_mask in fallback cases Date: Fri, 29 Mar 2024 20:37:50 +1300 Message-Id: <20240329073750.20012-1-21cnbao@gmail.com> X-Mailer: git-send-email 2.34.1 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: Barry Song Fallback rates surpassing 90% have been observed on phones utilizing 64KiB CONT-PTE mTHP. In these scenarios, when one out of every 16 PTEs fails to allocate large folios, the remaining 15 PTEs fallback. Consequently, invoking vma_thp_gfp_mask seems redundant in such cases. Furthermore, abstaining from its use can also contribute to improved code readability. Cc: Ryan Roberts Cc: Kefeng Wang Cc: John Hubbard Cc: David Hildenbrand Cc: Alistair Popple Cc: Anshuman Khandual Cc: Catalin Marinas Cc: David Rientjes Cc: "Huang, Ying" Cc: Hugh Dickins Cc: Itaru Kitayama Cc: Kirill A. Shutemov Cc: Luis Chamberlain Cc: Matthew Wilcox (Oracle) Cc: Vlastimil Babka Cc: Yang Shi Cc: Yin Fengwei Cc: Yu Zhao Cc: Zi Yan Signed-off-by: Barry Song Acked-by: Yu Zhao Reviewed-by: Ryan Roberts --- mm/memory.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/mm/memory.c b/mm/memory.c index c9c1031c2ecb..010e7bb20d2b 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -4353,6 +4353,9 @@ static struct folio *alloc_anon_folio(struct vm_fault= *vmf) =20 pte_unmap(pte); =20 + if (!orders) + goto fallback; + /* Try allocating the highest of the remaining orders. */ gfp =3D vma_thp_gfp_mask(vma); while (orders) { --=20 2.34.1