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Date: Mon, 10 Jun 2024 16:15:26 -0400
From: Johannes Weiner <hannes@cmpxchg.org>
To: Usama Arif <usamaarif642@gmail.com>
Cc: akpm@linux-foundation.org, willy@infradead.org, yosryahmed@google.com,
	nphamcs@gmail.com, chengming.zhou@linux.dev, linux-mm@kvack.org,
	linux-kernel@vger.kernel.org, kernel-team@meta.com
Subject: Re: [PATCH] mm: Do not start/end writeback for pages stored in zswap
Message-ID: <20240610201526.GA2407021@cmpxchg.org>
References: <20240610143037.812955-1-usamaarif642@gmail.com>
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In-Reply-To: <20240610143037.812955-1-usamaarif642@gmail.com>

On Mon, Jun 10, 2024 at 03:30:37PM +0100, Usama Arif wrote:
> start/end writeback combination incorrectly increments NR_WRITTEN
> counter, eventhough the pages aren't written to disk. Pages successfully
> stored in zswap should just unlock folio and return from writepage.
> 
> Signed-off-by: Usama Arif <usamaarif642@gmail.com>

I also don't see anything in those start and end calls that wouldn't
be pointless churn for these pages.

Acked-by: Johannes Weiner <hannes@cmpxchg.org>