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Shutemov" , Hugh Dickins , David Hildenbrand , Vlastimil Babka Content-Transfer-Encoding: quoted-printable Message-Id: <6C0B267E-E36D-4014-8308-B948247D7FED@gmail.com> References: <20220729014041.21292-1-peterx@redhat.com> To: Peter Xu X-Mailer: Apple Mail (2.3696.120.41.1.1) ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1659114425; a=rsa-sha256; cv=none; b=TZCRozxvoCGKcL5RlK0VM7dVDJ/dmLHirv4xxliFEGtPJtN0R5pa2fjLyXQNE0jnsi+8Hz 6HtRMaqBhWn+JwcXTTjXoQJYPgY+dn+R6mgUI4j/rTx0Q+ivd4o2vjEIaSFLeojt+xkoVl Jsh/IOkBjWBvJZ4Zazaa/KfnNRWP3bc= ARC-Authentication-Results: i=1; imf09.hostedemail.com; dkim=pass header.d=gmail.com header.s=20210112 header.b=d7rrhYFD; dmarc=pass (policy=none) header.from=gmail.com; spf=pass (imf09.hostedemail.com: domain of nadav.amit@gmail.com designates 209.85.210.173 as permitted sender) smtp.mailfrom=nadav.amit@gmail.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1659114425; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=9o/kpxtwtGSAJRz7togZqH/jX2IzYG9txOU/MkOdGsk=; b=8l3LyITVeXqxamSavLOsuKVFuACc8H0G7bkDMh+pifuOp5l+0Usq6iCugXXWmVlsVFOvm/ HwB+SDGylS93+Pd5pW0PRlIXmdmRP6dsyeYlnh9KTC/EqBn8ofsBLQjYzmUayARKbBWOIj CUWKRDQh9u9osD1aJC/REhDOYSKXgSU= X-Rspamd-Queue-Id: BDA7014002B X-Rspam-User: Authentication-Results: imf09.hostedemail.com; dkim=pass header.d=gmail.com header.s=20210112 header.b=d7rrhYFD; dmarc=pass (policy=none) header.from=gmail.com; spf=pass (imf09.hostedemail.com: domain of nadav.amit@gmail.com designates 209.85.210.173 as permitted sender) smtp.mailfrom=nadav.amit@gmail.com X-Rspamd-Server: rspam09 X-Stat-Signature: 71645xeopiq78fjd8zorzcjggiooiewy X-HE-Tag: 1659114425-597985 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: On Jul 28, 2022, at 6:40 PM, Peter Xu wrote: > [Marking as RFC; only x86 is supported for now, plan to add a few more > archs when there's a formal version] >=20 > Problem > =3D=3D=3D=3D=3D=3D=3D >=20 > When migrate a page, right now we always mark the migrated page as = old. > The reason could be that we don't really know whether the page is hot = or > cold, so we could have taken it a default negative assuming that's = safer. Looks good to me. I just wonder whether the order of the patches should be different. I = always understood that separating the =E2=80=9Cenabling=E2=80=9D patch from the = others is not a good practice, since it complicates bisection. I guess it is more of a = minor issue for such a small patch-set=E2=80=A6