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Date: Thu, 9 Apr 2026 09:30:51 +0100
From: Lorenzo Stoakes <ljs@kernel.org>
To: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Michal Hocko <mhocko@suse.com>, 
	Andrew Morton <akpm@linux-foundation.org>, David Hildenbrand <david@kernel.org>, 
	Christian Brauner <brauner@kernel.org>, Alexander Viro <viro@zeniv.linux.org.uk>, 
	"Matthew Wilcox (Oracle)" <willy@infradead.org>, Jan Kara <jack@suse.cz>, 
	"Liam R. Howlett" <Liam.Howlett@oracle.com>, Mike Rapoport <rppt@kernel.org>, 
	Suren Baghdasaryan <surenb@google.com>, Vlastimil Babka <vbabka@kernel.org>, 
	linux-fsdevel@vger.kernel.org, linux-mm@kvack.org
Subject: Re: [PATCH RFC] fs: drop_caches: introduce per-node drop_caches
 interface
Message-ID: <addjLJ9MVTNQD7YZ@lucifer>
References: <20260409063503.3475420-1-wangkefeng.wang@huawei.com>
 <addP4MKmA8zfSN1o@tiehlicka>
 <dbb92553-58ba-42e1-b7df-b8450bd69d33@huawei.com>
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In-Reply-To: <dbb92553-58ba-42e1-b7df-b8450bd69d33@huawei.com>

On Thu, Apr 09, 2026 at 04:08:37PM +0800, Kefeng Wang wrote:
> On 4/9/2026 3:06 PM, Michal Hocko wrote:
> > Quite honestly drop_caches is not the best interface to build any new
> > functionality on top of. It has backfired a lot in the past and we have
> > tried to make it extra clear that this should be used for debugging
> > purposes only. Extending it further sounds like a bad step.
>
> I am not clear about this history of this interface, but some of our
> products do use this interface :(

All the more reason for us not to add another one like it...!