[PATCH v1 7/7] xfs: Add tracepoints and logging to alternate device retry

Allison Henderson
2018-11-28T03:52:42Z

This patch adds new log entries and trace points to the
alternate device retry error path

Signed-off-by: Allison Henderson <allison.henderson@oracle.com>
---
fs/xfs/xfs_buf.c | 14 +++++++++++++-
fs/xfs/xfs_buf.h | 1 +
fs/xfs/xfs_trace.h | 6 +++++-
3 files changed, 19 insertions(+), 2 deletions(-)

diff --git a/fs/xfs/xfs_buf.c b/fs/xfs/xfs_buf.c
index 81f6491..f203ddebe 100644
--- a/fs/xfs/xfs_buf.c
+++ b/fs/xfs/xfs_buf.c
@@ -833,6 +833,10 @@ xfs_buf_read_map(
for (i = 0; i <= blk_queue_get_mirrors(q); i++) {
bp->b_error = 0;
bp->b_rw_hint = i;
+
+ if (i > 0)
+ xfs_alert(bp->b_target->bt_mount,
+ "Retrying read from disk %hu",i);
_xfs_buf_read(bp, flags);

switch (bp->b_error) {
@@ -840,6 +844,11 @@ xfs_buf_read_map(
case -EFSCORRUPTED:
case -EFSBADCRC:
/* loop again */
+ trace_xfs_buf_ioretry(bp, _RET_IP_);
+ xfs_alert(bp->b_target->bt_mount,
+ "Read error:%d from disk number %hu",
+ bp->b_error, bp->b_rw_hint);
+
continue;
default:
goto retry_done;
@@ -852,8 +861,11 @@ xfs_buf_read_map(
* if we had to try more than one mirror to sucessfully read
* the buffer, write the buffer back
*/
- if (!bp->b_error && i > 0)
+ if (!bp->b_error && i > 0) {
+ xfs_alert(bp->b_target->bt_mount,
+ "Re-writeing verified data");
xfs_bwrite(bp);
+ }

return bp;
}
diff --git a/fs/xfs/xfs_buf.h b/fs/xfs/xfs_buf.h
index db138e5..23c9c3e 100644
--- a/fs/xfs/xfs_buf.h
+++ b/fs/xfs/xfs_buf.h
@@ -300,6 +300,7 @@ extern void __xfs_buf_ioerror(struct xfs_buf *bp, int error,
xfs_failaddr_t failaddr);
#define xfs_buf_ioerror(bp, err) __xfs_buf_ioerror((bp), (err), __this_address)
extern void xfs_buf_ioerror_alert(struct xfs_buf *, const char *func);
+extern void xfs_buf_ioretry_alert(struct xfs_buf *, const char *func);

extern int __xfs_buf_submit(struct xfs_buf *bp, bool);
static inline int xfs_buf_submit(struct xfs_buf *bp)
diff --git a/fs/xfs/xfs_trace.h b/fs/xfs/xfs_trace.h
index 3043e5e..1d98a3e 100644
--- a/fs/xfs/xfs_trace.h
+++ b/fs/xfs/xfs_trace.h
@@ -276,6 +276,7 @@ DECLARE_EVENT_CLASS(xfs_buf_class,
__field(int, pincount)
__field(unsigned, lockval)
__field(unsigned, flags)
+ __field(unsigned short, rw_hint)
__field(unsigned long, caller_ip)
),
TP_fast_assign(
@@ -286,10 +287,11 @@ DECLARE_EVENT_CLASS(xfs_buf_class,
__entry->pincount = atomic_read(&bp->b_pin_count);
__entry->lockval = bp->b_sema.count;
__entry->flags = bp->b_flags;
+ __entry->rw_hint = bp->b_rw_hint;
__entry->caller_ip = caller_ip;
),
TP_printk("dev %d:%d bno 0x%llx nblks 0x%x hold %d pincount %d "
- "lock %d flags %s caller %pS",
+ "lock %d flags %s rw_hint %hu caller %pS",
MAJOR(__entry->dev), MINOR(__entry->dev),
(unsigned long long)__entry->bno,
__entry->nblks,
@@ -297,6 +299,7 @@ DECLARE_EVENT_CLASS(xfs_buf_class,
__entry->pincount,
__entry->lockval,
__print_flags(__entry->flags, "|", XFS_BUF_FLAGS),
+ __entry->rw_hint,
(void *)__entry->caller_ip)
)

@@ -309,6 +312,7 @@ DEFINE_BUF_EVENT(xfs_buf_free);
DEFINE_BUF_EVENT(xfs_buf_hold);
DEFINE_BUF_EVENT(xfs_buf_rele);
DEFINE_BUF_EVENT(xfs_buf_iodone);
+DEFINE_BUF_EVENT(xfs_buf_ioretry);
DEFINE_BUF_EVENT(xfs_buf_submit);
DEFINE_BUF_EVENT(xfs_buf_lock);
DEFINE_BUF_EVENT(xfs_buf_lock_done);
--
2.7.4