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Date:   Fri, 21 Apr 2023 13:54:53 +0100
From:   Mel Gorman <mgorman@techsingularity.net>
To:     Johannes Weiner <hannes@cmpxchg.org>
Cc:     linux-mm@kvack.org, Kaiyang Zhao <kaiyang2@cs.cmu.edu>,
        Vlastimil Babka <vbabka@suse.cz>,
        David Rientjes <rientjes@google.com>,
        linux-kernel@vger.kernel.org, kernel-team@fb.com
Subject: Re: [RFC PATCH 06/26] mm: page_alloc: consolidate free page
 accounting
Message-ID: <20230421125453.np6b5hirktkj6ji5@techsingularity.net>
References: <20230418191313.268131-1-hannes@cmpxchg.org>
 <20230418191313.268131-7-hannes@cmpxchg.org>
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In-Reply-To: <20230418191313.268131-7-hannes@cmpxchg.org>
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On Tue, Apr 18, 2023 at 03:12:53PM -0400, Johannes Weiner wrote:
> Free page accounting currently happens a bit too high up the call
> stack, where it has to deal with guard pages, compaction capturing,
> block stealing and even page isolation. This is subtle and fragile,
> and makes it difficult to hack on the code.
> 
> Push the accounting down to where pages enter and leave the physical
> freelists, where all these higher-level exceptions are of no concern.
> 
> Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>

I didn't look too closely at this one as I'm scanning through to see how
the overall series works and this is mostly a mechanical patch.
However, it definitely breaks build

> @@ -843,7 +843,7 @@ static int __init debug_guardpage_minorder_setup(char *buf)
>  early_param("debug_guardpage_minorder", debug_guardpage_minorder_setup);
>  
>  static inline bool set_page_guard(struct zone *zone, struct page *page,
> -				unsigned int order, int migratetype)
> +				  unsigned int order
>  {
>  	if (!debug_guardpage_enabled())
>  		return false;

Here

-- 
Mel Gorman
SUSE Labs