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Subject: Re: [PATCH v14 011/138] mm/lru: Add folio LRU functions
To:     "Matthew Wilcox (Oracle)" <willy@infradead.org>,
        linux-kernel@vger.kernel.org
Cc:     linux-mm@kvack.org, linux-fsdevel@vger.kernel.org,
        Yu Zhao <yuzhao@google.com>, Christoph Hellwig <hch@lst.de>,
        David Howells <dhowells@redhat.com>,
        "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>
References: <20210715033704.692967-1-willy@infradead.org>
 <20210715033704.692967-12-willy@infradead.org>
From:   Vlastimil Babka <vbabka@suse.cz>
Message-ID: <91fb7d5b-9f5f-855e-2c87-dab105d5c977@suse.cz>
Date:   Tue, 10 Aug 2021 18:01:16 +0200
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On 7/15/21 5:34 AM, Matthew Wilcox (Oracle) wrote:
> Handle arbitrary-order folios being added to the LRU.  By definition,
> all pages being added to the LRU were already head or base pages, but
> call page_folio() on them anyway to get the type right and avoid the
> buried calls to compound_head().
> 
> Saves 783 bytes of kernel text; no functions grow.
> 
> Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
> Reviewed-by: Yu Zhao <yuzhao@google.com>
> Reviewed-by: Christoph Hellwig <hch@lst.de>
> Reviewed-by: David Howells <dhowells@redhat.com>
> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>

Acked-by: Vlastimil Babka <vbabka@suse.cz>

Actually looking at the git version, which has also this:

 static __always_inline void update_lru_size(struct lruvec *lruvec,
                                enum lru_list lru, enum zone_type zid,
-                               int nr_pages)
+                               long nr_pages)
 {

Why now and here? Some of the functions called from update_lru_size()
still take int so this looks arbitrary?