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Date: Thu, 18 Apr 2024 16:04:44 +0100
From: Simon Horman <horms@kernel.org>
To: Eric Dumazet <edumazet@google.com>
Cc: "David S. Miller" <davem@davemloft.net>,
	Jakub Kicinski <kuba@kernel.org>, Paolo Abeni <pabeni@redhat.com>,
	Jamal Hadi Salim <jhs@mojatatu.com>,
	Toke =?utf-8?Q?H=C3=B8iland-J=C3=B8rgensen?= <toke@redhat.com>,
	Cong Wang <xiyou.wangcong@gmail.com>, Jiri Pirko <jiri@resnulli.us>,
	netdev@vger.kernel.org, eric.dumazet@gmail.com
Subject: Re: [PATCH v2 net-next 11/14] net_sched: sch_hfsc: implement
 lockless accesses to q->defcls
Message-ID: <20240418150444.GF3975545@kernel.org>
References: <20240418073248.2952954-1-edumazet@google.com>
 <20240418073248.2952954-12-edumazet@google.com>
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In-Reply-To: <20240418073248.2952954-12-edumazet@google.com>

On Thu, Apr 18, 2024 at 07:32:45AM +0000, Eric Dumazet wrote:
> Instead of relying on RTNL, hfsc_dump_qdisc() can use READ_ONCE()
> annotation, paired with WRITE_ONCE() one in hfsc_change_qdisc().
> 
> Use READ_ONCE(q->defcls) in hfsc_classify() to
> no longer acquire qdisc lock from hfsc_change_qdisc().
> 
> Signed-off-by: Eric Dumazet <edumazet@google.com>

Reviewed-by: Simon Horman <horms@kernel.org>