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Date: Tue, 28 May 2024 15:40:27 +0200
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From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
To: "Vlastimil Babka (SUSE)" <vbabka@kernel.org>
Cc: Shakeel Butt <shakeel.butt@linux.dev>,
	Andrew Morton <akpm@linux-foundation.org>,
	Johannes Weiner <hannes@cmpxchg.org>,
	Michal Hocko <mhocko@kernel.org>,
	Roman Gushchin <roman.gushchin@linux.dev>,
	Muchun Song <muchun.song@linux.dev>, linux-mm@kvack.org,
	linux-kernel@vger.kernel.org, Thomas Gleixner <tglx@linutronix.de>
Subject: Re: [PATCH] memcg: Remove the lockdep assert from
 __mod_objcg_mlstate().
Message-ID: <20240528134027.OxDASsS3@linutronix.de>
References: <20240528121928.i-Gu7Jvg@linutronix.de>
 <09e085bb-f09e-4901-a2dd-a0b789bb8a4d@kernel.org>
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In-Reply-To: <09e085bb-f09e-4901-a2dd-a0b789bb8a4d@kernel.org>

On 2024-05-28 14:34:55 [+0200], Vlastimil Babka (SUSE) wrote:
> > The safety of the counter update is already ensured by
> > VM_WARN_ON_IRQS_ENABLED() which is part of memcg_stats_lock() and does
> > not require yet another check.
> 
> I think here it's __mod_memcg_lruvec_state() doing the VM_WARN_ON_ as we
> don't go through memcg_stats_lock()?

It is either VM_WARN_ON_IRQS_ENABLED() directly as in
__mod_memcg_lruvec_state() (which is special) or memcg_stats_lock().

Do you want me to rephrase this part?

Sebastian