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Message-ID: <13e2fac7-5f65-4257-a478-4359cec31939@redhat.com>
Date: Wed, 31 Jan 2024 16:11:21 +0100
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Subject: Re: [PATCH v3 00/15] mm/memory: optimize fork() with PTE-mapped THP
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To: Ryan Roberts <ryan.roberts@arm.com>, linux-kernel@vger.kernel.org
Cc: linux-mm@kvack.org, Andrew Morton <akpm@linux-foundation.org>,
 Matthew Wilcox <willy@infradead.org>, Russell King <linux@armlinux.org.uk>,
 Catalin Marinas <catalin.marinas@arm.com>, Will Deacon <will@kernel.org>,
 Dinh Nguyen <dinguyen@kernel.org>, Michael Ellerman <mpe@ellerman.id.au>,
 Nicholas Piggin <npiggin@gmail.com>,
 Christophe Leroy <christophe.leroy@csgroup.eu>,
 "Aneesh Kumar K.V" <aneesh.kumar@kernel.org>,
 "Naveen N. Rao" <naveen.n.rao@linux.ibm.com>,
 Paul Walmsley <paul.walmsley@sifive.com>, Palmer Dabbelt
 <palmer@dabbelt.com>, Albert Ou <aou@eecs.berkeley.edu>,
 Alexander Gordeev <agordeev@linux.ibm.com>,
 Gerald Schaefer <gerald.schaefer@linux.ibm.com>,
 Heiko Carstens <hca@linux.ibm.com>, Vasily Gorbik <gor@linux.ibm.com>,
 Christian Borntraeger <borntraeger@linux.ibm.com>,
 Sven Schnelle <svens@linux.ibm.com>, "David S. Miller"
 <davem@davemloft.net>, linux-arm-kernel@lists.infradead.org,
 linuxppc-dev@lists.ozlabs.org, linux-riscv@lists.infradead.org,
 linux-s390@vger.kernel.org, sparclinux@vger.kernel.org
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From: David Hildenbrand <david@redhat.com>
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In-Reply-To: <eeafba09-058f-47da-bbb9-19ded5ad05da@arm.com>
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>> dontneed should hopefully/likely see a speedup.
> 
> Yes, but that's almost exactly the same path as munmap, so I'm sure it really
> adds much for this particular series. 

Right, that's why I'm not including these measurements. dontneed vs. 
munmap is more about measuring the overhead of VMA modifications + page 
table reclaim.

> Anyway, on Altra at least, I'm seeing no
> regressions, so:
> 
> Tested-by: Ryan Roberts <ryan.roberts@arm.com>
> 

Thanks!

-- 
Cheers,

David / dhildenb