[<prev] [next>] [<thread-prev] [day] [month] [year] [list]
Message-ID: <1350128388.1917.1.camel@kjgkr>
Date: Sat, 13 Oct 2012 20:39:48 +0900
From: Jaegeuk Kim <jaegeuk.kim@...il.com>
To: Arnd Bergmann <arnd@...db.de>
Cc: ����� <jaegeuk.kim@...sung.com>,
viro@...iv.linux.org.uk, 'Theodore Ts'o' <tytso@....edu>,
gregkh@...uxfoundation.org, linux-kernel@...r.kernel.org,
chur.lee@...sung.com, cm224.lee@...sung.com,
jooyoung.hwang@...sung.com
Subject: Re: [PATCH 02/16] f2fs: add on-disk layout
2012-10-12 (금), 21:05 +0000, Arnd Bergmann:
> On Friday 05 October 2012 20:56:44 김재극 wrote:
> > +struct f2fs_nat_entry {
> > + __u8 version;
> > + __le32 ino;
> > + __le32 block_addr;
> > +} __packed;
> > +
> > +struct f2fs_nat_block {
> > + struct f2fs_nat_entry entries[NAT_ENTRY_PER_BLOCK];
> > +} __packed;
>
> Using "__packed" on structure is rather inefficient on CPU architectures
> that cannot do aligned accesses. I would suggest you remove this
> attribute everywhere you can. The f2fs_nat_entry is particularly
> suboptimal because it is 9 bytes long, and I'm not sure if this
> can be reasonably changed to a multiple of four.
>
> In all other cases, you should try to lay out the structures
> so that each member is naturally aligned and you don't need any __packed
> attributes, in particular for those that are accessed a lot.
>
Ok, I'll check all the in-memory data structures.
Thank you for comments.
> Arnd
> --
> 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/
--
Jaegeuk Kim
Samsung
--
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/
Powered by blists - more mailing lists