Message-ID: <f88106b26a2b647a1541d049999d5546d2ee3e51.camel@kernel.org>
Date: Thu, 28 Sep 2023 08:01:50 -0400
From: Jeff Layton <jlayton@...nel.org>
To: Amir Goldstein <amir73il@...il.com>
Cc: Alexander Viro <viro@...iv.linux.org.uk>, Christian Brauner
 <brauner@...nel.org>, Linus Torvalds <torvalds@...ux-foundation.org>, David
 Sterba <dsterba@...e.cz>, Theodore Ts'o <tytso@....edu>, Eric Biederman
 <ebiederm@...ssion.com>,  Kees Cook <keescook@...omium.org>, Jeremy Kerr
 <jk@...abs.org>, Arnd Bergmann <arnd@...db.de>,  Michael Ellerman
 <mpe@...erman.id.au>, Nicholas Piggin <npiggin@...il.com>, Christophe Leroy
 <christophe.leroy@...roup.eu>, Heiko Carstens <hca@...ux.ibm.com>, Vasily
 Gorbik <gor@...ux.ibm.com>, Alexander Gordeev <agordeev@...ux.ibm.com>,
 Christian Borntraeger <borntraeger@...ux.ibm.com>, Sven Schnelle
 <svens@...ux.ibm.com>, Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
 Arve Hjønnevåg <arve@...roid.com>, Todd Kjos
 <tkjos@...roid.com>, Martijn Coenen <maco@...roid.com>, Joel Fernandes
 <joel@...lfernandes.org>, Carlos Llamas <cmllamas@...gle.com>, Suren
 Baghdasaryan <surenb@...gle.com>, Mattia Dongili <malattia@...ux.it>,
 Dennis Dalessandro <dennis.dalessandro@...nelisnetworks.com>, Jason
 Gunthorpe <jgg@...pe.ca>,  Leon Romanovsky <leon@...nel.org>, Brad Warrum
 <bwarrum@...ux.ibm.com>, Ritu Agarwal <rituagar@...ux.ibm.com>, Hans de
 Goede <hdegoede@...hat.com>, Ilpo Järvinen
 <ilpo.jarvinen@...ux.intel.com>, Mark Gross <markgross@...nel.org>, Jiri
 Slaby <jirislaby@...nel.org>, Eric Van Hensbergen <ericvh@...nel.org>,
 Latchesar Ionkov <lucho@...kov.net>, Dominique Martinet
 <asmadeus@...ewreck.org>, Christian Schoenebeck <linux_oss@...debyte.com>, 
 David Sterba <dsterba@...e.com>, David Howells <dhowells@...hat.com>, Marc
 Dionne <marc.dionne@...istor.com>,  Ian Kent <raven@...maw.net>, Luis de
 Bethencourt <luisbg@...nel.org>, Salah Triki <salah.triki@...il.com>,
 "Tigran A. Aivazian" <aivazian.tigran@...il.com>,  Chris Mason
 <clm@...com>, Josef Bacik <josef@...icpanda.com>, Xiubo Li
 <xiubli@...hat.com>,  Ilya Dryomov <idryomov@...il.com>, Jan Harkes
 <jaharkes@...cmu.edu>, coda@...cmu.edu, Joel Becker <jlbec@...lplan.org>,
 Christoph Hellwig <hch@....de>, Nicolas Pitre <nico@...xnic.net>, "Rafael
 J. Wysocki" <rafael@...nel.org>, Ard Biesheuvel <ardb@...nel.org>, Gao
 Xiang <xiang@...nel.org>, Chao Yu <chao@...nel.org>,  Yue Hu
 <huyue2@...lpad.com>, Jeffle Xu <jefflexu@...ux.alibaba.com>, Namjae Jeon
 <linkinjeon@...nel.org>, Sungjong Seo <sj1557.seo@...sung.com>, Jan Kara
 <jack@...e.com>, Andreas Dilger <adilger.kernel@...ger.ca>, Jaegeuk Kim
 <jaegeuk@...nel.org>, OGAWA Hirofumi <hirofumi@...l.parknet.co.jp>, 
 Christoph Hellwig <hch@...radead.org>, Miklos Szeredi <miklos@...redi.hu>,
 Bob Peterson <rpeterso@...hat.com>, Andreas Gruenbacher
 <agruenba@...hat.com>, Richard Weinberger <richard@....at>, Anton Ivanov
 <anton.ivanov@...bridgegreys.com>, Johannes Berg
 <johannes@...solutions.net>, Mikulas Patocka
 <mikulas@...ax.karlin.mff.cuni.cz>,  Mike Kravetz
 <mike.kravetz@...cle.com>, Muchun Song <muchun.song@...ux.dev>, Jan Kara
 <jack@...e.cz>,  David Woodhouse <dwmw2@...radead.org>, Dave Kleikamp
 <shaggy@...nel.org>, Tejun Heo <tj@...nel.org>, Trond Myklebust
 <trond.myklebust@...merspace.com>, Anna Schumaker <anna@...nel.org>, Chuck
 Lever <chuck.lever@...cle.com>, Neil Brown <neilb@...e.de>, Olga
 Kornievskaia <kolga@...app.com>, Dai Ngo <Dai.Ngo@...cle.com>, Tom Talpey
 <tom@...pey.com>,  Ryusuke Konishi <konishi.ryusuke@...il.com>, Anton
 Altaparmakov <anton@...era.com>, Konstantin Komarov
 <almaz.alexandrovich@...agon-software.com>, Mark Fasheh <mark@...heh.com>, 
 Joseph Qi <joseph.qi@...ux.alibaba.com>, Bob Copeland <me@...copeland.com>,
 Mike Marshall <hubcap@...ibond.com>, Martin Brandenburg
 <martin@...ibond.com>, Luis Chamberlain <mcgrof@...nel.org>, Iurii Zaikin
 <yzaikin@...gle.com>, Tony Luck <tony.luck@...el.com>,  "Guilherme G.
 Piccoli" <gpiccoli@...lia.com>, Anders Larsen <al@...rsen.net>, Steve
 French <sfrench@...ba.org>, Paulo Alcantara <pc@...guebit.com>, Ronnie
 Sahlberg <lsahlber@...hat.com>, Shyam Prasad N <sprasad@...rosoft.com>,
 Sergey Senozhatsky <senozhatsky@...omium.org>, Phillip Lougher
 <phillip@...ashfs.org.uk>, Steven Rostedt <rostedt@...dmis.org>, Masami
 Hiramatsu <mhiramat@...nel.org>, Evgeniy Dushistov <dushistov@...l.ru>,
 Chandan Babu R <chandan.babu@...cle.com>, "Darrick J. Wong"
 <djwong@...nel.org>, Damien Le Moal <dlemoal@...nel.org>, Naohiro Aota
 <naohiro.aota@....com>, Johannes Thumshirn <jth@...nel.org>, Alexei
 Starovoitov <ast@...nel.org>, Daniel Borkmann <daniel@...earbox.net>,
 Andrii Nakryiko <andrii@...nel.org>, Martin KaFai Lau
 <martin.lau@...ux.dev>, Song Liu <song@...nel.org>, Yonghong Song
 <yonghong.song@...ux.dev>, John Fastabend <john.fastabend@...il.com>, KP
 Singh <kpsingh@...nel.org>, Stanislav Fomichev <sdf@...gle.com>, Hao Luo
 <haoluo@...gle.com>, Jiri Olsa <jolsa@...nel.org>,  Hugh Dickins
 <hughd@...gle.com>, Andrew Morton <akpm@...ux-foundation.org>, "David S.
 Miller" <davem@...emloft.net>, Eric Dumazet <edumazet@...gle.com>, Jakub
 Kicinski <kuba@...nel.org>, Paolo Abeni <pabeni@...hat.com>, John Johansen
 <john.johansen@...onical.com>, Paul Moore <paul@...l-moore.com>, James
 Morris <jmorris@...ei.org>, "Serge E. Hallyn" <serge@...lyn.com>, Stephen
 Smalley <stephen.smalley.work@...il.com>, Eric Paris
 <eparis@...isplace.org>,  linux-fsdevel@...r.kernel.org,
 linux-kernel@...r.kernel.org, linux-mm@...ck.org, 
 linuxppc-dev@...ts.ozlabs.org, linux-s390@...r.kernel.org, 
 platform-driver-x86@...r.kernel.org, linux-rdma@...r.kernel.org, 
 linux-serial@...r.kernel.org, linux-usb@...r.kernel.org,
 v9fs@...ts.linux.dev,  linux-afs@...ts.infradead.org,
 autofs@...r.kernel.org,  linux-btrfs@...r.kernel.org,
 ceph-devel@...r.kernel.org,  codalist@...a.cs.cmu.edu,
 linux-efi@...r.kernel.org,  linux-erofs@...ts.ozlabs.org,
 linux-ext4@...r.kernel.org,  linux-f2fs-devel@...ts.sourceforge.net,
 gfs2@...ts.linux.dev,  linux-um@...ts.infradead.org,
 linux-mtd@...ts.infradead.org,  jfs-discussion@...ts.sourceforge.net,
 linux-nfs@...r.kernel.org,  linux-nilfs@...r.kernel.org,
 linux-ntfs-dev@...ts.sourceforge.net,  ntfs3@...ts.linux.dev,
 ocfs2-devel@...ts.linux.dev,  linux-karma-devel@...ts.sourceforge.net,
 devel@...ts.orangefs.org,  linux-unionfs@...r.kernel.org,
 linux-hardening@...r.kernel.org,  reiserfs-devel@...r.kernel.org,
 linux-cifs@...r.kernel.org,  samba-technical@...ts.samba.org,
 linux-trace-kernel@...r.kernel.org,  linux-xfs@...r.kernel.org,
 bpf@...r.kernel.org, netdev@...r.kernel.org,  apparmor@...ts.ubuntu.com,
 linux-security-module@...r.kernel.org,  selinux@...r.kernel.org
Subject: Re: [PATCH 87/87] fs: move i_blocks up a few places in struct inode

On Thu, 2023-09-28 at 14:35 +0300, Amir Goldstein wrote:
> On Thu, Sep 28, 2023 at 2:06 PM Jeff Layton <jlayton@...nel.org> wrote:
> > 
> > The recent change to use discrete integers instead of struct timespec64
> > in struct inode shaved 8 bytes off of it, but it also moves the i_lock
> > into the previous cacheline, away from the fields that it protects.
> > 
> > Move i_blocks up above the i_lock, which moves the new 4 byte hole to
> > just after the timestamps, without changing the size of the structure.
> > 
> 
> Instead of creating an implicit hole, can you please move i_generation
> to fill the 4 bytes hole.
> 
> It makes sense in the same cache line with i_ino and I could
> use the vacant 4 bytes hole above i_fsnotify_mask to expand the
> mask to 64bit (the 32bit event mask space is running out).
> 
> Thanks,
> Amir.
> 

Sounds like a plan. Resulting struct inode size is the same (616 bytes
with my kdevops kconfig). BTW: all of these changes are in my "amtime"
branch if anyone wants to pull them down.
--
Jeff Layton <jlayton@...nel.org>

Powered by blists - more mailing lists