From: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
To: Linus Torvalds <torvalds@linux-foundation.org>,
Bradley Morgan <brads@mainlining.org>
Cc: "Paul E. McKenney" <paulmck@kernel.org>,
rcu@vger.kernel.org, linux-kernel@vger.kernel.org,
kernel-team@meta.com, Boqun Feng <boqun@kernel.org>,
Steven Rostedt <rostedt@goodmis.org>,
lkmm@lists.linux.dev, Zqiang <qiang.zhang@linux.dev>,
Wang Lian <lianux.mm@gmail.com>,
Kunwu Chan <kunwu.chan@gmail.com>,
Nicholas Piggin <npiggin@gmail.com>,
Michael Ellerman <mpe@ellerman.id.au>,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
Sebastian Andrzej Siewior <bigeasy@linutronix.de>,
Will Deacon <will@kernel.org>,
Peter Zijlstra <peterz@infradead.org>,
Alan Stern <stern@rowland.harvard.edu>,
John Stultz <jstultz@google.com>,
Andrew Morton <akpm@linux-foundation.org>,
Frederic Weisbecker <frederic@kernel.org>,
Joel Fernandes <joel@joelfernandes.org>,
Josh Triplett <josh@joshtriplett.org>,
Uladzislau Rezki <urezki@gmail.com>,
Lai Jiangshan <jiangshanlai@gmail.com>,
Zqiang <qiang.zhang1211@gmail.com>,
Ingo Molnar <mingo@redhat.com>, Waiman Long <longman@redhat.com>,
Mark Rutland <mark.rutland@arm.com>,
Thomas Gleixner <tglx@linutronix.de>,
Vlastimil Babka <vbabka@suse.cz>,
maged.michael@gmail.com, Mateusz Guzik <mjguzik@gmail.com>,
Jonas Oberhauser <jonas.oberhauser@huaweicloud.com>,
linux-mm@kvack.org
Subject: Re: [PATCH 01/28] hazptr: Implement Hazard Pointers
Date: Sat, 19 Sep 2026 13:19:09 -0400 [thread overview]
Message-ID: <c0de0530-e919-4cb8-89de-56a20a8a09fc@efficios.com> (raw)
In-Reply-To: <CAHk-=wjyniJy-CX1muCrsZp-i-sLGRYeRYEPN7sw9orRZUCwag@mail.gmail.com>
On 2026-09-19 13:00, Linus Torvalds wrote:
[...]
> Now, obviously, the thing that would impress me is something like the
> dcache. If *that* can be converted, and it shows real improvements on
> some real benchmark, then I'm sold.
[ Side-discussion, not related to hazard pointers. ]
Talking about dcache improvements:
I've been working on scalability of rename, directory move, and
directory listing, basically killing dcache global locks, seqlocks
and rwlocks which significantly limit dcache update and read-side
scalability.
Those improvements are based on RCU, not hazard pointers, and on a new
"RCU pseudo-transaction" concept I've invented earlier this year.
I'm preparing a paper and I plan to present it at LPC in Prague.
My benchmark results are on a userspace port of the Linux kernel dentry
cache at this point, so it's not ready for anything close to upstream at
this stage.
Cheers,
Mathieu
--
Mathieu Desnoyers
EfficiOS Inc.
https://www.efficios.com
next prev parent reply other threads:[~2026-09-19 17:19 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <e9669b34-12c2-4cf2-a887-315f581f0789@paulmck-laptop>
2026-09-19 0:00 ` [PATCH 01/28] hazptr: Implement Hazard Pointers Paul E. McKenney
2026-09-19 16:30 ` Linus Torvalds
[not found] ` <6B1FC39D-6EB0-433A-8E49-E5EFC9379AD7@mainlining.org>
2026-09-19 17:00 ` Linus Torvalds
2026-09-19 17:09 ` Mathieu Desnoyers
2026-09-19 18:09 ` Boqun Feng
2026-09-19 17:19 ` Mathieu Desnoyers [this message]
2026-09-19 18:18 ` Paul E. McKenney
[not found] ` <183D0BFB-F900-4AFD-B7CA-6D63591FA26B@mainlining.org>
2026-09-19 17:56 ` Paul E. McKenney
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