[PATCH 026/145] xfs: add tracepoints and error injection for deferred extent freeing

["Darrick J. Wong" <darrick.wong@xxxxxxxxxx>]

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@xxxxxxxxxx>
---
 include/xfs_trace.h |    3 +++
 libxfs/xfs_alloc.c  |    7 +++++++
 libxfs/xfs_bmap.c   |    2 ++
 3 files changed, 12 insertions(+)


diff --git a/include/xfs_trace.h b/include/xfs_trace.h
index dd0d46f..cdabd18 100644
--- a/include/xfs_trace.h
+++ b/include/xfs_trace.h
@@ -184,6 +184,9 @@
 #define trace_xfs_defer_pending_cancel(...)    ((void) 0)
 #define trace_xfs_defer_init(...)              ((void) 0)
 
+#define trace_xfs_bmap_free_deferred(...)      ((void) 0)
+#define trace_xfs_bmap_free_defer(...)         ((void) 0)
+
 /* set c = c to avoid unused var warnings */
 #define trace_xfs_perag_get(a,b,c,d)   ((c) = (c))
 #define trace_xfs_perag_get_tag(a,b,c,d) ((c) = (c))
diff --git a/libxfs/xfs_alloc.c b/libxfs/xfs_alloc.c
index 8454816..06133c0 100644
--- a/libxfs/xfs_alloc.c
+++ b/libxfs/xfs_alloc.c
@@ -2700,6 +2700,13 @@ 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/libxfs/xfs_bmap.c b/libxfs/xfs_bmap.c
index 5385800..33e181c 100644
--- a/libxfs/xfs_bmap.c
+++ b/libxfs/xfs_bmap.c
@@ -588,6 +588,8 @@ xfs_bmap_add_free(
        new = kmem_zone_alloc(xfs_bmap_free_item_zone, KM_SLEEP);
        new->xbfi_startblock = bno;
        new->xbfi_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->xbfi_list);
 }