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From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
To: linux-kernel@vger.kernel.org, rcu@vger.kernel.org,
	Andrew Morton <akpm@linux-foundation.org>
Cc: MengEn Sun <mengensun@tencent.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	YueHong Wu <yuehongwu@tencent.com>,
	"Paul E. McKenney" <paulmck@kernel.org>,
	Joel Fernandes <joel@joelfernandes.org>,
	Josh Triplett <josh@joshtriplett.org>,
	Boqun Feng <boqun.feng@gmail.com>,
	Uladzislau Rezki <urezki@gmail.com>,
	Steven Rostedt <rostedt@goodmis.org>,
	Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
	Lai Jiangshan <jiangshanlai@gmail.com>,
	Zqiang <qiang.zhang1211@gmail.com>
Subject: Re: [PATCH 0/4] ucount: Simplify refcounting with rcuref_t.
Message-ID: <20250207204854.rc1gron_@linutronix.de>
References: <20250203150525.456525-1-bigeasy@linutronix.de>
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In-Reply-To: <20250203150525.456525-1-bigeasy@linutronix.de>

On 2025-02-03 16:05:21 [+0100], To linux-kernel@vger.kernel.org wrote:
> I noticed that the atomic_dec_and_lock_irqsave() in put_ucounts() loops
> sometimes even during boot. Something like 2-3 iterations but still.
> This series replaces the refcounting with rcuref_t and adds a RCU
> lookup.
> This allows a lockless lookup in alloc_ucounts() if the entry is
> available and a cmpxchg()less put of the item.

Andrew, could you please take this series?

Sebastian