From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from relay.sgi.com (relay3.corp.sgi.com [198.149.34.15]) by oss.sgi.com (Postfix) with ESMTP id 5B5377CA2 for ; Thu, 14 Jul 2016 05:52:54 -0500 (CDT) Received: from cuda.sgi.com (cuda3.sgi.com [192.48.176.15]) by relay3.corp.sgi.com (Postfix) with ESMTP id B8A3FAC002 for ; Thu, 14 Jul 2016 03:52:50 -0700 (PDT) Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) by cuda.sgi.com with ESMTP id neD7jF2yw3tCd7aX (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO) for ; Thu, 14 Jul 2016 03:52:49 -0700 (PDT) Date: Thu, 14 Jul 2016 06:52:47 -0400 From: Brian Foster Subject: Re: [PATCH 1/3] xfs: helper to set flags on uncached buffer reads Message-ID: <20160714105247.GA4207@bfoster.bfoster> References: <1468426595-35032-1-git-send-email-bfoster@redhat.com> <1468426595-35032-2-git-send-email-bfoster@redhat.com> <20160714000103.GR1922@dastard> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20160714000103.GR1922@dastard> List-Id: XFS Filesystem from SGI List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: xfs-bounces@oss.sgi.com Sender: xfs-bounces@oss.sgi.com To: Dave Chinner Cc: xfs@oss.sgi.com On Thu, Jul 14, 2016 at 10:01:04AM +1000, Dave Chinner wrote: > On Wed, Jul 13, 2016 at 12:16:33PM -0400, Brian Foster wrote: > > xfs_buf_read_uncached() allocates an uncached buffer and performs a read > > in one go. As part of the upcoming buftarg I/O accounting mechanism, > > some sites may need to set flags on a buffer before I/O submission. > > > > Create a new helper to support the ability to set flags on a buffer > > before it is submitted for I/O. This use case is the exception, so > > create a wrapper for the original xfs_buf_read_uncached(). > > > > Signed-off-by: Brian Foster > > --- > > fs/xfs/xfs_buf.c | 20 +++++++++++++++++--- > > fs/xfs/xfs_buf.h | 4 ++++ > > 2 files changed, 21 insertions(+), 3 deletions(-) > > > > diff --git a/fs/xfs/xfs_buf.c b/fs/xfs/xfs_buf.c > > index 4665ff6..f007713 100644 > > --- a/fs/xfs/xfs_buf.c > > +++ b/fs/xfs/xfs_buf.c > > @@ -693,13 +693,14 @@ xfs_buf_readahead_map( > > * buffer containing the disk contents or nothing. > > */ > > int > > -xfs_buf_read_uncached( > > +xfs_buf_read_uncached_flags( > > struct xfs_buftarg *target, > > xfs_daddr_t daddr, > > size_t numblks, > > int flags, > > struct xfs_buf **bpp, > > - const struct xfs_buf_ops *ops) > > + const struct xfs_buf_ops *ops, > > + int bflags) > > { > > We already have a flags field being passed in. Why can't that be > used to pass the XBF_NO_IOACCT flag? i.e: > Oops, I read over that too quickly as I saw it being passed into alloc_page() and assumed it was for memory allocation flags. It is in fact for buffer flags.. we just use xb_to_gfp() to select GFP_* flags based on the buffer flags. I'll drop this patch and fold the xfs_buf_read_cached() fixup into patch 2. Thanks. Brian > > ASSERT(bp->b_map_count == 1); > > bp->b_bn = XFS_BUF_DADDR_NULL; /* always null for uncached buffers */ > > bp->b_maps[0].bm_bn = daddr; > > - bp->b_flags |= XBF_READ; > > + bp->b_flags |= XBF_READ | bflags; > > bp->b_flags |= XBF_READ; > bp->b_flags |= (flags & XBF_NO_IOACCT); > > Cheers, > > Dave. > -- > Dave Chinner > david@fromorbit.com > > _______________________________________________ > xfs mailing list > xfs@oss.sgi.com > http://oss.sgi.com/mailman/listinfo/xfs _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs