Re: [PATCH v6 02/12] xfs: add helpers to compute log item overhead

Darrick J. Wong
2025-04-08T23:21:32Z

On Wed, Apr 09, 2025 at 08:50:57AM +1000, Dave Chinner wrote:
> On Tue, Apr 08, 2025 at 10:41:59AM +0000, John Garry wrote:
> > From: "Darrick J. Wong" <djwong@kernel.org>
> >
> > Add selected helpers to estimate the transaction reservation required to
> > write various log intent and buffer items to the log. These helpers
> > will be used by the online repair code for more precise estimations of
> > how much work can be done in a single transaction.
> >
> > Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
> > Signed-off-by: John Garry <john.g.garry@oracle.com>
> > ---
> > fs/xfs/libxfs/xfs_trans_resv.c | 6 +++---
> > fs/xfs/libxfs/xfs_trans_resv.h | 4 ++++
> > fs/xfs/xfs_bmap_item.c | 10 ++++++++++
> > fs/xfs/xfs_bmap_item.h | 3 +++
> > fs/xfs/xfs_buf_item.c | 19 +++++++++++++++++++
> > fs/xfs/xfs_buf_item.h | 3 +++
> > fs/xfs/xfs_extfree_item.c | 10 ++++++++++
> > fs/xfs/xfs_extfree_item.h | 3 +++
> > fs/xfs/xfs_log_cil.c | 4 +---
> > fs/xfs/xfs_log_priv.h | 13 +++++++++++++
> > fs/xfs/xfs_refcount_item.c | 10 ++++++++++
> > fs/xfs/xfs_refcount_item.h | 3 +++
> > fs/xfs/xfs_rmap_item.c | 10 ++++++++++
> > fs/xfs/xfs_rmap_item.h | 3 +++
> > 14 files changed, 95 insertions(+), 6 deletions(-)
> >
> > diff --git a/fs/xfs/libxfs/xfs_trans_resv.c b/fs/xfs/libxfs/xfs_trans_resv.c
> > index 13d00c7166e1..ce1393bd3561 100644
> > --- a/fs/xfs/libxfs/xfs_trans_resv.c
> > +++ b/fs/xfs/libxfs/xfs_trans_resv.c
> > @@ -47,7 +47,7 @@ xfs_buf_log_overhead(void)
> > * will be changed in a transaction. size is used to tell how many
> > * bytes should be reserved per item.
> > */
> > -STATIC uint
> > +uint
> > xfs_calc_buf_res(
> > uint nbufs,
> > uint size)
> > @@ -84,7 +84,7 @@ xfs_allocfree_block_count(
> > * in the same transaction as an allocation or a free, so we compute them
> > * separately.
> > */
> > -static unsigned int
> > +unsigned int
> > xfs_refcountbt_block_count(
> > struct xfs_mount *mp,
> > unsigned int num_ops)
> > @@ -129,7 +129,7 @@ xfs_rtrefcountbt_block_count(
> > * additional to the records and pointers that fit inside the inode
> > * forks.
> > */
> > -STATIC uint
> > +uint
> > xfs_calc_inode_res(
> > struct xfs_mount *mp,
> > uint ninodes)
> > diff --git a/fs/xfs/libxfs/xfs_trans_resv.h b/fs/xfs/libxfs/xfs_trans_resv.h
> > index 0554b9d775d2..e76052028cc9 100644
> > --- a/fs/xfs/libxfs/xfs_trans_resv.h
> > +++ b/fs/xfs/libxfs/xfs_trans_resv.h
> > @@ -97,6 +97,10 @@ struct xfs_trans_resv {
> >
> > void xfs_trans_resv_calc(struct xfs_mount *mp, struct xfs_trans_resv *resp);
> > uint xfs_allocfree_block_count(struct xfs_mount *mp, uint num_ops);
> > +unsigned int xfs_refcountbt_block_count(struct xfs_mount *mp,
> > + unsigned int num_ops);
> > +uint xfs_calc_buf_res(uint nbufs, uint size);
> > +uint xfs_calc_inode_res(struct xfs_mount *mp, uint ninodes);
>
> Why are these exported? They aren't used in this patch, and any code
> that doing calculate log reservation calculation should really be
> placed in xfs_trans_resv.c along with all the existing log
> reservation calculations...

I've redone this in a different manner, will send a full patchset after
it runs through QA.

--D

> -Dave
> --
> Dave Chinner
> david@fromorbit.com