[PATCH 19/47] xfs: add tracepoints and error injection for deferred extent freeing

Darrick J. Wong
2016-07-21T04:58:22Z

Add a couple of tracepoints for the deferred extent free operation and
a site for injecting errors while finishing the operation. This makes
it easier to debug deferred ops and test log redo.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
fs/xfs/libxfs/xfs_alloc.c | 7 +++++++
fs/xfs/libxfs/xfs_bmap.c | 2 ++
fs/xfs/xfs_error.h | 4 +++-
fs/xfs/xfs_trace.h | 5 ++++-
4 files changed, 16 insertions(+), 2 deletions(-)

diff --git a/fs/xfs/libxfs/xfs_alloc.c b/fs/xfs/libxfs/xfs_alloc.c
index 5993f87..22ac3f1 100644
--- a/fs/xfs/libxfs/xfs_alloc.c
+++ b/fs/xfs/libxfs/xfs_alloc.c
@@ -2702,6 +2702,13 @@ xfs_free_extent(

ASSERT(len != 0);

+ trace_xfs_bmap_free_deferred(mp, agno, 0, agbno, len);
+
+ if (XFS_TEST_ERROR(false, mp,
+ XFS_ERRTAG_FREE_EXTENT,
+ XFS_RANDOM_FREE_EXTENT))
+ return -EIO;
+
error = xfs_free_extent_fix_freelist(tp, agno, &agbp);
if (error)
return error;
diff --git a/fs/xfs/libxfs/xfs_bmap.c b/fs/xfs/libxfs/xfs_bmap.c
index 540a6b7..8e14ff4 100644
--- a/fs/xfs/libxfs/xfs_bmap.c
+++ b/fs/xfs/libxfs/xfs_bmap.c
@@ -596,6 +596,8 @@ xfs_bmap_add_free(
new = kmem_zone_alloc(xfs_bmap_free_item_zone, KM_SLEEP);
new->xefi_startblock = bno;
new->xefi_blockcount = (xfs_extlen_t)len;
+ trace_xfs_bmap_free_defer(mp, XFS_FSB_TO_AGNO(mp, bno), 0,
+ XFS_FSB_TO_AGBNO(mp, bno), len);
xfs_defer_add(dfops, XFS_DEFER_OPS_TYPE_FREE, &new->xefi_list);
}

diff --git a/fs/xfs/xfs_error.h b/fs/xfs/xfs_error.h
index 2e4f67f..da6f951 100644
--- a/fs/xfs/xfs_error.h
+++ b/fs/xfs/xfs_error.h
@@ -90,7 +90,8 @@ extern void xfs_verifier_error(struct xfs_buf *bp);
#define XFS_ERRTAG_STRATCMPL_IOERR 19
#define XFS_ERRTAG_DIOWRITE_IOERR 20
#define XFS_ERRTAG_BMAPIFORMAT 21
-#define XFS_ERRTAG_MAX 22
+#define XFS_ERRTAG_FREE_EXTENT 22
+#define XFS_ERRTAG_MAX 23

/*
* Random factors for above tags, 1 means always, 2 means 1/2 time, etc.
@@ -117,6 +118,7 @@ extern void xfs_verifier_error(struct xfs_buf *bp);
#define XFS_RANDOM_STRATCMPL_IOERR (XFS_RANDOM_DEFAULT/10)
#define XFS_RANDOM_DIOWRITE_IOERR (XFS_RANDOM_DEFAULT/10)
#define XFS_RANDOM_BMAPIFORMAT XFS_RANDOM_DEFAULT
+#define XFS_RANDOM_FREE_EXTENT 1

#ifdef DEBUG
extern int xfs_error_test_active;
diff --git a/fs/xfs/xfs_trace.h b/fs/xfs/xfs_trace.h
index a45b030..939caf5 100644
--- a/fs/xfs/xfs_trace.h
+++ b/fs/xfs/xfs_trace.h
@@ -2417,9 +2417,12 @@ DEFINE_DEFER_PENDING_EVENT(xfs_defer_pending_cancel);
DEFINE_DEFER_PENDING_EVENT(xfs_defer_pending_finish);
DEFINE_DEFER_PENDING_EVENT(xfs_defer_pending_abort);

-DEFINE_PHYS_EXTENT_DEFERRED_EVENT(xfs_defer_phys_extent);
DEFINE_MAP_EXTENT_DEFERRED_EVENT(xfs_defer_map_extent);

+#define DEFINE_BMAP_FREE_DEFERRED_EVENT DEFINE_PHYS_EXTENT_DEFERRED_EVENT
+DEFINE_BMAP_FREE_DEFERRED_EVENT(xfs_bmap_free_defer);
+DEFINE_BMAP_FREE_DEFERRED_EVENT(xfs_bmap_free_deferred);
+
#endif /* _TRACE_XFS_H */

#undef TRACE_INCLUDE_PATH