[PATCH 4/8] xfs: pass a CIL context to xlog_write()

Dave Chinner
2021-06-17T08:26:25Z

From: Dave Chinner <dchinner@redhat.com>

Pass the CIL context to xlog_write() rather than a pointer to a LSN
variable. Only the CIL checkpoint calls to xlog_write() need to know
about the start LSN of the writes, so rework xlog_write to directly
write the LSNs into the CIL context structure.

This removes the commit_lsn variable from xlog_cil_push_work(), so
now we only have to issue the commit record ordering wakeup from
there.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
---
fs/xfs/xfs_log.c | 22 +++++++++++++++++-----
fs/xfs/xfs_log_cil.c | 19 ++++++++-----------
fs/xfs/xfs_log_priv.h | 4 ++--
3 files changed, 27 insertions(+), 18 deletions(-)

diff --git a/fs/xfs/xfs_log.c b/fs/xfs/xfs_log.c
index cf661c155786..fc0e43c57683 100644
--- a/fs/xfs/xfs_log.c
+++ b/fs/xfs/xfs_log.c
@@ -871,7 +871,7 @@ xlog_write_unmount_record(
*/
if (log->l_targ != log->l_mp->m_ddev_targp)
blkdev_issue_flush(log->l_targ->bt_bdev);
- return xlog_write(log, &lv_chain, ticket, NULL, NULL, reg.i_len);
+ return xlog_write(log, NULL, &lv_chain, ticket, NULL, reg.i_len);
}

/*
@@ -2383,9 +2383,9 @@ xlog_write_partial(
int
xlog_write(
struct xlog *log,
+ struct xfs_cil_ctx *ctx,
struct list_head *lv_chain,
struct xlog_ticket *ticket,
- xfs_lsn_t *start_lsn,
struct xlog_in_core **commit_iclog,
uint32_t len)
{
@@ -2408,9 +2408,21 @@ xlog_write(
if (error)
return error;

- /* start_lsn is the LSN of the first iclog written to. */
- if (start_lsn)
- *start_lsn = be64_to_cpu(iclog->ic_header.h_lsn);
+ /*
+ * If we have a CIL context, record the LSN of the iclog we were just
+ * granted space to start writing into. If the context doesn't have
+ * a start_lsn recorded, then this iclog will contain the start record
+ * for the checkpoint. Otherwise this write contains the commit record
+ * for the checkpoint.
+ */
+ if (ctx) {
+ spin_lock(&ctx->cil->xc_push_lock);
+ if (!ctx->start_lsn)
+ ctx->start_lsn = be64_to_cpu(iclog->ic_header.h_lsn);
+ else
+ ctx->commit_lsn = be64_to_cpu(iclog->ic_header.h_lsn);
+ spin_unlock(&ctx->cil->xc_push_lock);
+ }

lv = list_first_entry_or_null(lv_chain, struct xfs_log_vec, lv_list);
while (lv) {
diff --git a/fs/xfs/xfs_log_cil.c b/fs/xfs/xfs_log_cil.c
index 2c8b25888c53..35fc3e57d870 100644
--- a/fs/xfs/xfs_log_cil.c
+++ b/fs/xfs/xfs_log_cil.c
@@ -790,14 +790,13 @@ xlog_cil_build_trans_hdr(
*/
int
xlog_cil_write_commit_record(
- struct xlog *log,
- struct xlog_ticket *ticket,
- struct xlog_in_core **iclog,
- xfs_lsn_t *lsn)
+ struct xfs_cil_ctx *ctx,
+ struct xlog_in_core **iclog)
{
+ struct xlog *log = ctx->cil->xc_log;
struct xlog_op_header ophdr = {
.oh_clientid = XFS_TRANSACTION,
- .oh_tid = cpu_to_be32(ticket->t_tid),
+ .oh_tid = cpu_to_be32(ctx->ticket->t_tid),
.oh_flags = XLOG_COMMIT_TRANS,
};
struct xfs_log_iovec reg = {
@@ -818,8 +817,8 @@ xlog_cil_write_commit_record(
return -EIO;

/* account for space used by record data */
- ticket->t_curr_res -= reg.i_len;
- error = xlog_write(log, &lv_chain, ticket, lsn, iclog, reg.i_len);
+ ctx->ticket->t_curr_res -= reg.i_len;
+ error = xlog_write(log, ctx, &lv_chain, ctx->ticket, iclog, reg.i_len);
if (error)
xfs_force_shutdown(log->l_mp, SHUTDOWN_LOG_IO_ERROR);
return error;
@@ -1038,7 +1037,7 @@ xlog_cil_push_work(
* use the commit record lsn then we can move the tail beyond the grant
* write head.
*/
- error = xlog_write(log, &ctx->lv_chain, ctx->ticket, &ctx->start_lsn,
+ error = xlog_write(log, ctx, &ctx->lv_chain, ctx->ticket,
NULL, num_bytes);

/*
@@ -1083,8 +1082,7 @@ xlog_cil_push_work(
}
spin_unlock(&cil->xc_push_lock);

- error = xlog_cil_write_commit_record(log, ctx->ticket, &commit_iclog,
- &commit_lsn);
+ error = xlog_cil_write_commit_record(ctx, &commit_iclog);
if (error)
goto out_abort_free_ticket;

@@ -1104,7 +1102,6 @@ xlog_cil_push_work(
* and wake up anyone who is waiting for the commit to complete.
*/
spin_lock(&cil->xc_push_lock);
- ctx->commit_lsn = commit_lsn;
wake_up_all(&cil->xc_commit_wait);
spin_unlock(&cil->xc_push_lock);

diff --git a/fs/xfs/xfs_log_priv.h b/fs/xfs/xfs_log_priv.h
index 26f26769d1c6..af8a9dfa8068 100644
--- a/fs/xfs/xfs_log_priv.h
+++ b/fs/xfs/xfs_log_priv.h
@@ -487,8 +487,8 @@ xlog_write_adv_cnt(void **ptr, int *len, int *off, size_t bytes)

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 list_head *lv_chain,
- struct xlog_ticket *tic, xfs_lsn_t *start_lsn,
+int xlog_write(struct xlog *log, struct xfs_cil_ctx *ctx,
+ struct list_head *lv_chain, struct xlog_ticket *tic,
struct xlog_in_core **commit_iclog, uint32_t len);

void xfs_log_ticket_ungrant(struct xlog *log, struct xlog_ticket *ticket);
--
2.31.1