linux-mm.kvack.org archive mirror
 help / color / mirror / Atom feed
From: Matthew Wilcox <willy@infradead.org>
To: Barry Song <21cnbao@gmail.com>
Cc: akpm@linux-foundation.org, linux-mm@kvack.org,
	"Barry Song" <v-songbaohua@oppo.com>,
	"Russell King" <linux@armlinux.org.uk>,
	"Catalin Marinas" <catalin.marinas@arm.com>,
	"Will Deacon" <will@kernel.org>,
	"Huacai Chen" <chenhuacai@kernel.org>,
	"WANG Xuerui" <kernel@xen0n.name>,
	"Madhavan Srinivasan" <maddy@linux.ibm.com>,
	"Michael Ellerman" <mpe@ellerman.id.au>,
	"Nicholas Piggin" <npiggin@gmail.com>,
	"Christophe Leroy" <christophe.leroy@csgroup.eu>,
	"Paul Walmsley" <pjw@kernel.org>,
	"Palmer Dabbelt" <palmer@dabbelt.com>,
	"Albert Ou" <aou@eecs.berkeley.edu>,
	"Alexandre Ghiti" <alex@ghiti.fr>,
	"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>,
	"Dave Hansen" <dave.hansen@linux.intel.com>,
	"Andy Lutomirski" <luto@kernel.org>,
	"Peter Zijlstra" <peterz@infradead.org>,
	"Thomas Gleixner" <tglx@linutronix.de>,
	"Ingo Molnar" <mingo@redhat.com>,
	"Borislav Petkov" <bp@alien8.de>,
	x86@kernel.org, "H . Peter Anvin" <hpa@zytor.com>,
	"David Hildenbrand" <david@kernel.org>,
	"Lorenzo Stoakes" <lorenzo.stoakes@oracle.com>,
	"Liam R . Howlett" <Liam.Howlett@oracle.com>,
	"Vlastimil Babka" <vbabka@suse.cz>,
	"Mike Rapoport" <rppt@kernel.org>,
	"Suren Baghdasaryan" <surenb@google.com>,
	"Michal Hocko" <mhocko@suse.com>,
	"Pedro Falcato" <pfalcato@suse.de>,
	"Jarkko Sakkinen" <jarkko@kernel.org>,
	"Oscar Salvador" <osalvador@suse.de>,
	"Kuninori Morimoto" <kuninori.morimoto.gx@renesas.com>,
	"Oven Liyang" <liyangouwen1@oppo.com>,
	"Mark Rutland" <mark.rutland@arm.com>,
	"Ada Couprie Diaz" <ada.coupriediaz@arm.com>,
	"Robin Murphy" <robin.murphy@arm.com>,
	"Kristina Martšenko" <kristina.martsenko@arm.com>,
	"Kevin Brodsky" <kevin.brodsky@arm.com>,
	"Yeoreum Yun" <yeoreum.yun@arm.com>,
	"Wentao Guan" <guanwentao@uniontech.com>,
	"Thorsten Blum" <thorsten.blum@linux.dev>,
	"Steven Rostedt" <rostedt@goodmis.org>,
	"Yunhui Cui" <cuiyunhui@bytedance.com>,
	"Nam Cao" <namcao@linutronix.de>, "Chris Li" <chrisl@kernel.org>,
	"Kairui Song" <kasong@tencent.com>,
	"Kemeng Shi" <shikemeng@huaweicloud.com>,
	"Nhat Pham" <nphamcs@gmail.com>, "Baoquan He" <bhe@redhat.com>,
	linux-arm-kernel@lists.infradead.org,
	linux-kernel@vger.kernel.org, loongarch@lists.linux.dev,
	linuxppc-dev@lists.ozlabs.org, linux-riscv@lists.infradead.org,
	linux-s390@vger.kernel.org, linux-fsdevel@vger.kernel.org
Subject: Re: [RFC PATCH 0/2] mm: continue using per-VMA lock when retrying page faults after I/O
Date: Thu, 27 Nov 2025 04:09:17 +0000	[thread overview]
Message-ID: <aSfO7fA-04SBtTug@casper.infradead.org> (raw)
In-Reply-To: <20251127011438.6918-1-21cnbao@gmail.com>

On Thu, Nov 27, 2025 at 09:14:36AM +0800, Barry Song wrote:
> There is no need to always fall back to mmap_lock if the per-VMA
> lock was released only to wait for pagecache or swapcache to
> become ready.

Something I've been wondering about is removing all the "drop the MM
locks while we wait for I/O" gunk.  It's a nice amount of code removed:

 include/linux/pagemap.h |  8 +---
 mm/filemap.c            | 98 ++++++++++++-------------------------------------
 mm/internal.h           | 21 -----------
 mm/memory.c             | 13 +------
 mm/shmem.c              |  6 ---
 5 files changed, 27 insertions(+), 119 deletions(-)

and I'm not sure we still need to do it with per-VMA locks.  What I
have here doesn't boot and I ran out of time to debug it.


  parent reply	other threads:[~2025-11-27  4:09 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-11-27  1:14 Barry Song
2025-11-27  1:14 ` [RFC PATCH 1/2] mm/filemap: Retry fault by VMA lock if the lock was released for I/O Barry Song
2025-11-27 10:52   ` Pedro Falcato
2025-11-27 11:39     ` Barry Song
2025-11-27 16:26       ` Pedro Falcato
2025-11-27  1:14 ` [RFC PATCH 2/2] mm/swapin: Retry swapin " Barry Song
2025-11-27  4:09 ` Matthew Wilcox [this message]
2025-11-27  4:22   ` [RFC PATCH 0/2] mm: continue using per-VMA lock when retrying page faults after I/O Barry Song
2025-11-27  4:42     ` Barry Song
2025-11-27 19:43     ` Matthew Wilcox
2025-11-27 20:29       ` Barry Song
2025-11-27 21:52         ` Barry Song
2025-11-30  0:28         ` Suren Baghdasaryan
2025-11-30  2:56           ` Barry Song
2025-11-30  5:38       ` Shakeel Butt

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=aSfO7fA-04SBtTug@casper.infradead.org \
    --to=willy@infradead.org \
    --cc=21cnbao@gmail.com \
    --cc=Liam.Howlett@oracle.com \
    --cc=ada.coupriediaz@arm.com \
    --cc=agordeev@linux.ibm.com \
    --cc=akpm@linux-foundation.org \
    --cc=alex@ghiti.fr \
    --cc=aou@eecs.berkeley.edu \
    --cc=bhe@redhat.com \
    --cc=borntraeger@linux.ibm.com \
    --cc=bp@alien8.de \
    --cc=catalin.marinas@arm.com \
    --cc=chenhuacai@kernel.org \
    --cc=chrisl@kernel.org \
    --cc=christophe.leroy@csgroup.eu \
    --cc=cuiyunhui@bytedance.com \
    --cc=dave.hansen@linux.intel.com \
    --cc=david@kernel.org \
    --cc=gerald.schaefer@linux.ibm.com \
    --cc=gor@linux.ibm.com \
    --cc=guanwentao@uniontech.com \
    --cc=hca@linux.ibm.com \
    --cc=hpa@zytor.com \
    --cc=jarkko@kernel.org \
    --cc=kasong@tencent.com \
    --cc=kernel@xen0n.name \
    --cc=kevin.brodsky@arm.com \
    --cc=kristina.martsenko@arm.com \
    --cc=kuninori.morimoto.gx@renesas.com \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-fsdevel@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=linux-riscv@lists.infradead.org \
    --cc=linux-s390@vger.kernel.org \
    --cc=linux@armlinux.org.uk \
    --cc=linuxppc-dev@lists.ozlabs.org \
    --cc=liyangouwen1@oppo.com \
    --cc=loongarch@lists.linux.dev \
    --cc=lorenzo.stoakes@oracle.com \
    --cc=luto@kernel.org \
    --cc=maddy@linux.ibm.com \
    --cc=mark.rutland@arm.com \
    --cc=mhocko@suse.com \
    --cc=mingo@redhat.com \
    --cc=mpe@ellerman.id.au \
    --cc=namcao@linutronix.de \
    --cc=nphamcs@gmail.com \
    --cc=npiggin@gmail.com \
    --cc=osalvador@suse.de \
    --cc=palmer@dabbelt.com \
    --cc=peterz@infradead.org \
    --cc=pfalcato@suse.de \
    --cc=pjw@kernel.org \
    --cc=robin.murphy@arm.com \
    --cc=rostedt@goodmis.org \
    --cc=rppt@kernel.org \
    --cc=shikemeng@huaweicloud.com \
    --cc=surenb@google.com \
    --cc=svens@linux.ibm.com \
    --cc=tglx@linutronix.de \
    --cc=thorsten.blum@linux.dev \
    --cc=v-songbaohua@oppo.com \
    --cc=vbabka@suse.cz \
    --cc=will@kernel.org \
    --cc=x86@kernel.org \
    --cc=yeoreum.yun@arm.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox