From: majianpeng <majianpeng@gmail.com>
To: "Neil Brown" <neilb@suse.de>
Cc: viro <viro@ZenIV.linux.org.uk>,
linux-raid <linux-raid@vger.kernel.org>,
linux-fsdevel <linux-fsdevel@vger.kernel.org>
Subject: Re: Re: [PATCH 2/2] raid5: For write performance, remove REQ_SYNC when write was odirect.
Date: Mon, 16 Jul 2012 15:11:29 +0800 [thread overview]
Message-ID: <201207161511247039289@gmail.com> (raw)
In-Reply-To: 20120716170717.5d5ee04c@notabene.brown
On 2012-07-16 15:07 NeilBrown <neilb@suse.de> Wrote:
>On Mon, 16 Jul 2012 14:42:54 +0800 majianpeng <majianpeng@gmail.com> wrote:
>
>> On 2012-07-16 13:40 NeilBrown <neilb@suse.de> Wrote:
>> >On Mon, 16 Jul 2012 09:31:55 +0800 majianpeng <majianpeng@gmail.com> wrote:
>> >
[snip]
>> > Normal 'sync' requests use WRITE_SYNC which includes "REQ_NOIDLE" which means
>> > /* don't anticipate more IO after this one */
>> > O_DIRECT request use WRITE_ODIRECT which does not include this flag.
>> >
>
>> Using REQ_NOIDEL to difference odirect and sync.Why not using:
>> + if (bi->bi_rw & WRITE_ODIRECT)
>> + bi->bi_rw &= ~REQ_SYNC;
>
>Because that code is wrong. WRITE_ODIRECT is not one flag, it is two flags
>'or'ed together. So this code does not do what you expect.
>
No, I used those code test and it's ok.
The code used & not &&.
Maybe I wrong?
>
>>
[snip]
next prev parent reply other threads:[~2012-07-16 7:10 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-07-16 1:31 [PATCH 2/2] raid5: For write performance, remove REQ_SYNC when write was odirect majianpeng
2012-07-16 5:40 ` NeilBrown
2012-07-16 5:47 ` majianpeng
2012-07-16 6:42 ` majianpeng
2012-07-16 7:07 ` NeilBrown
2012-07-16 7:11 ` majianpeng [this message]
2012-07-16 7:30 ` NeilBrown
2012-07-16 8:14 ` majianpeng
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