From mboxrd@z Thu Jan 1 00:00:00 1970 From: Wu Fengguang Subject: Re: [PATCH 8/8] readahead: dont do start-of-file readahead after lseek() Date: Tue, 22 Nov 2011 22:18:29 +0800 Message-ID: <20111122141829.GB29261@localhost> References: <20111121091819.394895091@intel.com> <20111121093847.015852579@intel.com> <20111121153624.dea4f320.akpm@linux-foundation.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Linux Memory Management List , "linux-fsdevel@vger.kernel.org" , Rik van Riel , Linus Torvalds , LKML , Andi Kleen To: Andrew Morton Return-path: Content-Disposition: inline In-Reply-To: <20111121153624.dea4f320.akpm@linux-foundation.org> Sender: owner-linux-mm@kvack.org List-Id: linux-fsdevel.vger.kernel.org > > --- linux-next.orig/fs/read_write.c 2011-11-20 22:02:01.000000000 +0800 > > +++ linux-next/fs/read_write.c 2011-11-20 22:02:03.000000000 +0800 > > @@ -47,6 +47,10 @@ static loff_t lseek_execute(struct file > > file->f_pos = offset; > > file->f_version = 0; > > } > > + > > + if (!(file->f_ra.ra_flags & READAHEAD_LSEEK)) > > + file->f_ra.ra_flags |= READAHEAD_LSEEK; > > + > > return offset; > > } > > Confused. How does READAHEAD_LSEEK get cleared again? I thought it's not necessary (at least for this case). But yeah, it's good to clear it to make it more reasonable and avoid unexpected things. And it would be simple to do, in ra_submit(): - ra->ra_flags &= ~READAHEAD_MMAP; + ra->ra_flags &= ~(READAHEAD_MMAP | READAHEAD_LSEEK); Thanks, Fengguang -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org