On Fri, Mar 05, 2021 at 04:11:25PM +1100, Dave Chinner wrote: > From: Dave Chinner <dchinner@xxxxxxxxxx> > > The caller of xlog_write() usually has a close accounting of the > aggregated vector length contained in the log vector chain passed to > xlog_write(). There is no need to iterate the chain to calculate he > length of the data in xlog_write_calculate_len() if the caller is > already iterating that chain to build it. > > Passing in the vector length avoids doing an extra chain iteration, > which can be a significant amount of work given that large CIL > commits can have hundreds of thousands of vectors attached to the > chain. > > Signed-off-by: Dave Chinner <dchinner@xxxxxxxxxx> > --- > fs/xfs/xfs_log.c | 37 ++++++------------------------------- > fs/xfs/xfs_log_cil.c | 18 +++++++++++++----- > fs/xfs/xfs_log_priv.h | 2 +- > 3 files changed, 20 insertions(+), 37 deletions(-) > ... > diff --git a/fs/xfs/xfs_log_cil.c b/fs/xfs/xfs_log_cil.c > index 7a5e6bdb7876..34abc3bae587 100644 > --- a/fs/xfs/xfs_log_cil.c > +++ b/fs/xfs/xfs_log_cil.c ... > @@ -893,6 +898,9 @@ xlog_cil_push_work( > * transaction header here as it is not accounted for in xlog_write(). > */ > xlog_cil_build_trans_hdr(ctx, &thdr, &lvhdr, num_iovecs); > + num_iovecs += lvhdr.lv_niovecs; What's the point of this if num_iovecs is only used by xlog_cil_build_trans_hdr()? Brian > + num_bytes += lvhdr.lv_bytes; > + > > /* > * Before we format and submit the first iclog, we have to ensure that > @@ -907,7 +915,7 @@ xlog_cil_push_work( > * write head. > */ > error = xlog_write(log, &lvhdr, ctx->ticket, &ctx->start_lsn, NULL, > - XLOG_START_TRANS); > + XLOG_START_TRANS, num_bytes); > if (error) > goto out_abort_free_ticket; > > diff --git a/fs/xfs/xfs_log_priv.h b/fs/xfs/xfs_log_priv.h > index 8ee6a5f74396..003c11653955 100644 > --- a/fs/xfs/xfs_log_priv.h > +++ b/fs/xfs/xfs_log_priv.h > @@ -462,7 +462,7 @@ void xlog_print_tic_res(struct xfs_mount *mp, struct xlog_ticket *ticket); > void xlog_print_trans(struct xfs_trans *); > int xlog_write(struct xlog *log, struct xfs_log_vec *log_vector, > struct xlog_ticket *tic, xfs_lsn_t *start_lsn, > - struct xlog_in_core **commit_iclog, uint optype); > + struct xlog_in_core **commit_iclog, uint optype, uint32_t len); > int xlog_commit_record(struct xlog *log, struct xlog_ticket *ticket, > struct xlog_in_core **iclog, xfs_lsn_t *lsn); > void xlog_state_switch_iclogs(struct xlog *log, struct xlog_in_core *iclog, > -- > 2.28.0 >
