From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wr0-f200.google.com (mail-wr0-f200.google.com [209.85.128.200]) by kanga.kvack.org (Postfix) with ESMTP id A5B486810C8 for ; Fri, 25 Aug 2017 17:39:39 -0400 (EDT) Received: by mail-wr0-f200.google.com with SMTP id w14so1362149wrc.5 for ; Fri, 25 Aug 2017 14:39:39 -0700 (PDT) Received: from atrey.karlin.mff.cuni.cz (atrey.karlin.mff.cuni.cz. [195.113.26.193]) by mx.google.com with ESMTPS id u19si5915226wrg.502.2017.08.25.14.39.37 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 25 Aug 2017 14:39:38 -0700 (PDT) Date: Fri, 25 Aug 2017 23:39:36 +0200 From: Pavel Machek Subject: Re: [RFC PATCH] treewide: remove GFP_TEMPORARY allocation flag Message-ID: <20170825213936.GA13576@amd> References: <20170728091904.14627-1-mhocko@kernel.org> <20170823175709.GA22743@xo-6d-61-c0.localdomain> <20170825063545.GA25498@dhcp22.suse.cz> <20170825072818.GA15494@amd> <20170825080442.GF25498@dhcp22.suse.cz> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="tKW2IUtsqtDRztdT" Content-Disposition: inline In-Reply-To: <20170825080442.GF25498@dhcp22.suse.cz> Sender: owner-linux-mm@kvack.org List-ID: To: Michal Hocko Cc: linux-mm@kvack.org, Mel Gorman , Matthew Wilcox , Vlastimil Babka , Neil Brown , Theodore Ts'o , Andrew Morton , LKML --tKW2IUtsqtDRztdT Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Fri 2017-08-25 10:04:42, Michal Hocko wrote: > On Fri 25-08-17 09:28:19, Pavel Machek wrote: > > On Fri 2017-08-25 08:35:46, Michal Hocko wrote: > > > On Wed 23-08-17 19:57:09, Pavel Machek wrote: > [...] > > > > Dunno. < 1msec probably is temporary, 1 hour probably is not. If it= causes > > > > problems, can you just #define GFP_TEMPORARY GFP_KERNEL ? Treewide = replace, > > > > and then starting again goes not look attractive to me. > > >=20 > > > I do not think we want a highlevel GFP_TEMPORARY without any meaning. > > > This just supports spreading the flag usage without a clear semantic > > > and it will lead to even bigger mess. Once we can actually define what > > > the flag means we can also add its users based on that new semantic. > >=20 > > It has real meaning. >=20 > Which is? "This allocation is temporary. It lasts milliseconds, not hours." > > You can define more exact meaning, and then adjust the usage. But > > there's no need to do treewide replacement... >=20 > I have checked most of them and except for the initially added onces the > large portion where added without a good reasons or even break an > intuitive meaning by taking locks. I don't see it. kmalloc() itself takes locks. Of course everyone takes locks. I don't think that's intuitive meaning. > Seriously, if we need a short term semantic it should be clearly defined > first. "milliseconds, not hours." > Is there any specific case why you think this patch is in a wrong > direction? E.g. a measurable regression? Not playing that game. You should argue why it is improvement. And I don't believe you did. Best regards, Pavel --=20 (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blo= g.html --tKW2IUtsqtDRztdT Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iEYEARECAAYFAlmgmRgACgkQMOfwapXb+vJ2UgCglElb/+e1pPxqwMoRZsqLZwXk pq8An0jftnFQ+KPeYDtmMOH5x0Eb4BnC =MIek -----END PGP SIGNATURE----- --tKW2IUtsqtDRztdT-- -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org