From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christoph Hellwig <hch@infradead.org>
Subject: Re: [RFC][PATCH v3] readahead: introduce O_RANDOM for
	POSIX_FADV_RANDOM
Date: Mon, 4 Jan 2010 02:33:28 -0500
Message-ID: <20100104073328.GA3422@infradead.org>
References: <20091225000717.GA26949@yahoo-inc.com> <87aax18xms.fsf@basil.nowhere.org> <20091230051540.GA16308@localhost> <20091230052402.GB26364@localhost> <873a2s8hmp.fsf@basil.nowhere.org> <20100104045020.GA21021@localhost> <20100104161719.a0bb35ad.sfr@canb.auug.org.au>
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Cc: Wu Fengguang <fengguang.wu@intel.com>,
	Andi Kleen <andi@firstfloor.org>,
	Andrew Morton <akpm@linux-foundation.org>,
	Quentin Barnes <qbarnes+nfs@yahoo-inc.com>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	"linux-fsdevel@vger.kernel.org" <linux-fsdevel@vger.kernel.org>,
	Nick Piggin <npiggin@suse.de>,
	Steven Whitehouse <swhiteho@redhat.com>,
	David Howells <dhowells@redhat.com>,
	Al Viro <viro@zeniv.linux.org.uk>,
	Jonathan Corbet <corbet@lwn.net>,
	Christoph Hellwig <hch@infradead.org>
To: Stephen Rothwell <sfr@canb.auug.org.au>
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On Mon, Jan 04, 2010 at 04:17:19PM +1100, Stephen Rothwell wrote:
> > @@ -80,6 +80,10 @@
> >  #define O_NDELAY	O_NONBLOCK
> >  #endif
> >  
> > +#ifndef O_RANDOM
> > +#define O_RANDOM	010000000	/* random access pattern hint */
> > +#endif
> 
> This value conflicts with O_CLOEXEC on alpha and parisc and O_NOATIME on
> sparc.

Also when I tried to use this value for O_RSYNC and tested it I could
not actually see it getting propagated by the open code.

Eitherway I don't think an O_ value is a good idea for a simple access
pattern hint.