Message ID | 1468426595-35032-2-git-send-email-bfoster@redhat.com (mailing list archive) |
---|---|
State | Deferred, archived |
Headers | show |
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 <bfoster@redhat.com> > --- > 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: > 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.
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 <bfoster@redhat.com> > > --- > > 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
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) { struct xfs_buf *bp; @@ -713,7 +714,7 @@ xfs_buf_read_uncached( 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_ops = ops; xfs_buf_submit_wait(bp); @@ -727,6 +728,19 @@ xfs_buf_read_uncached( return 0; } +int +xfs_buf_read_uncached( + struct xfs_buftarg *target, + xfs_daddr_t daddr, + size_t numblks, + int flags, + struct xfs_buf **bpp, + const struct xfs_buf_ops *ops) +{ + return xfs_buf_read_uncached_flags(target, daddr, numblks, flags, bpp, + ops, 0); +} + /* * Return a buffer allocated as an empty buffer and associated to external * memory via xfs_buf_associate_memory() back to it's empty state. diff --git a/fs/xfs/xfs_buf.h b/fs/xfs/xfs_buf.h index 8bfb974..a3c7ba4 100644 --- a/fs/xfs/xfs_buf.h +++ b/fs/xfs/xfs_buf.h @@ -295,6 +295,10 @@ struct xfs_buf *xfs_buf_get_uncached(struct xfs_buftarg *target, size_t numblks, int xfs_buf_read_uncached(struct xfs_buftarg *target, xfs_daddr_t daddr, size_t numblks, int flags, struct xfs_buf **bpp, const struct xfs_buf_ops *ops); +int 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, int blags); + void xfs_buf_hold(struct xfs_buf *bp); /* Releasing Buffers */
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 <bfoster@redhat.com> --- fs/xfs/xfs_buf.c | 20 +++++++++++++++++--- fs/xfs/xfs_buf.h | 4 ++++ 2 files changed, 21 insertions(+), 3 deletions(-)