linux-kernel - Re: [PATCH 4/4] mm: remove direct calling of migration

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <55B638F1.9090407@suse.cz>
Date:	Mon, 27 Jul 2015 15:58:09 +0200
From:	Vlastimil Babka <vbabka@...e.cz>
To:	Gioh Kim <gioh.kim@....com>, jlayton@...chiereds.net,
	bfields@...ldses.org, iamjoonsoo.kim@....com,
	viro@...iv.linux.org.uk, mst@...hat.com, koct9i@...il.com,
	minchan@...nel.org, aquini@...hat.com,
	linux-fsdevel@...r.kernel.org,
	virtualization@...ts.linux-foundation.org,
	linux-kernel@...r.kernel.org, linux-api@...r.kernel.org,
	linux-mm@...ck.org
Cc:	dri-devel@...ts.freedesktop.org, akpm@...ux-foundation.org,
	Gioh Kim <gurugio@...mail.net>
Subject: Re: [PATCH 4/4] mm: remove direct calling of migration

On 07/13/2015 10:35 AM, Gioh Kim wrote:
> From: Gioh Kim <gurugio@...mail.net>
>
> Migration is completely generalized so that migrating mobile page
> is processed with lru-pages in move_to_new_page.
>
> Signed-off-by: Gioh Kim <gioh.kim@....com>
> Acked-by: Rafael Aquini <aquini@...hat.com>

Why not just fold this to Patch 3? You already modify this hunk there, 
and prior to patch 3, the hunk was balloon-pages specific. You made it 
look generic only to remove it, which is unneeded code churn and I don't 
think it adds anything wrt e.g. bisectability.

> ---
>   mm/migrate.c | 15 ---------------
>   1 file changed, 15 deletions(-)
>
> diff --git a/mm/migrate.c b/mm/migrate.c
> index 53f0081d..e6644ac 100644
> --- a/mm/migrate.c
> +++ b/mm/migrate.c
> @@ -844,21 +844,6 @@ static int __unmap_and_move(struct page *page, struct page *newpage,
>   		}
>   	}
>
> -	if (unlikely(mobile_page(page))) {
> -		/*
> -		 * A mobile page does not need any special attention from
> -		 * physical to virtual reverse mapping procedures.
> -		 * Skip any attempt to unmap PTEs or to remap swap cache,
> -		 * in order to avoid burning cycles at rmap level, and perform
> -		 * the page migration right away (proteced by page lock).
> -		 */
> -		lock_page(newpage);
> -		rc = page->mapping->a_ops->migratepage(page->mapping,
> -						       newpage, page, mode);
> -		unlock_page(newpage);
> -		goto out_unlock;
> -	}
> -
>   	/*
>   	 * Corner case handling:
>   	 * 1. When a new swap-cache page is read into, it is added to the LRU
>

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/