[PATCH v14 06/14] xfsprogs: Add state machine tracepoints

Allison Henderson
2020-12-18T07:27:04Z

Source kernel commit: 5421d11d87aa32479cb41c18e2487db3b3a75cde

This is a quick patch to add a new tracepoint: xfs_das_state_return. We
use this to track when ever a new state is set or -EAGAIN is returned

Signed-off-by: Allison Henderson <allison.henderson@oracle.com>
Signed-off-by: Allison Henderson <allison.henderson@oracle.com>
---
include/xfs_trace.h | 1 +
libxfs/xfs_attr.c | 22 +++++++++++++++++++++-
libxfs/xfs_attr_remote.c | 1 +
3 files changed, 23 insertions(+), 1 deletion(-)

diff --git a/include/xfs_trace.h b/include/xfs_trace.h
index a100263..5ca5d03 100644
--- a/include/xfs_trace.h
+++ b/include/xfs_trace.h
@@ -314,4 +314,5 @@
#define trace_xfs_perag_get_tag(a,b,c,d) ((c) = (c))
#define trace_xfs_perag_put(a,b,c,d) ((c) = (c))

+#define trace_xfs_das_state_return(a) ((void) 0)
#endif /* __TRACE_H__ */
diff --git a/libxfs/xfs_attr.c b/libxfs/xfs_attr.c
index 83400fc..e15344d 100644
--- a/libxfs/xfs_attr.c
+++ b/libxfs/xfs_attr.c
@@ -263,6 +263,7 @@ xfs_attr_set_shortform(
* We're still in XFS_DAS_UNINIT state here. We've converted the attr
* fork to leaf format and will restart with the leaf add.
*/
+ trace_xfs_das_state_return(XFS_DAS_UNINIT);
return -EAGAIN;
}

@@ -409,9 +410,11 @@ xfs_attr_set_iter(
* down into the node handling code below
*/
dac->flags |= XFS_DAC_DEFER_FINISH;
+ trace_xfs_das_state_return(dac->dela_state);
return -EAGAIN;
case 0:
dac->dela_state = XFS_DAS_FOUND_LBLK;
+ trace_xfs_das_state_return(dac->dela_state);
return -EAGAIN;
}
return error;
@@ -841,6 +844,7 @@ xfs_attr_leaf_addname(
return error;

dac->flags |= XFS_DAC_DEFER_FINISH;
+ trace_xfs_das_state_return(dac->dela_state);
return -EAGAIN;
}

@@ -874,6 +878,7 @@ xfs_attr_leaf_addname(
* Commit the flag value change and start the next trans in series.
*/
dac->dela_state = XFS_DAS_FLIP_LFLAG;
+ trace_xfs_das_state_return(dac->dela_state);
return -EAGAIN;
das_flip_flag:
/*
@@ -891,6 +896,8 @@ das_flip_flag:
das_rm_lblk:
if (args->rmtblkno) {
error = __xfs_attr_rmtval_remove(dac);
+ if (error == -EAGAIN)
+ trace_xfs_das_state_return(dac->dela_state);
if (error)
return error;
}
@@ -1142,6 +1149,7 @@ xfs_attr_node_addname(
* this point.
*/
dac->flags |= XFS_DAC_DEFER_FINISH;
+ trace_xfs_das_state_return(dac->dela_state);
return -EAGAIN;
}

@@ -1175,6 +1183,7 @@ xfs_attr_node_addname(
state = NULL;

dac->dela_state = XFS_DAS_FOUND_NBLK;
+ trace_xfs_das_state_return(dac->dela_state);
return -EAGAIN;
das_found_nblk:

@@ -1202,6 +1211,7 @@ das_alloc_node:
return error;

dac->flags |= XFS_DAC_DEFER_FINISH;
+ trace_xfs_das_state_return(dac->dela_state);
return -EAGAIN;
}

@@ -1236,6 +1246,7 @@ das_alloc_node:
* Commit the flag value change and start the next trans in series
*/
dac->dela_state = XFS_DAS_FLIP_NFLAG;
+ trace_xfs_das_state_return(dac->dela_state);
return -EAGAIN;
das_flip_flag:
/*
@@ -1253,6 +1264,10 @@ das_flip_flag:
das_rm_nblk:
if (args->rmtblkno) {
error = __xfs_attr_rmtval_remove(dac);
+
+ if (error == -EAGAIN)
+ trace_xfs_das_state_return(dac->dela_state);
+
if (error)
return error;
}
@@ -1396,6 +1411,8 @@ xfs_attr_node_remove_rmt (
* May return -EAGAIN to request that the caller recall this function
*/
error = __xfs_attr_rmtval_remove(dac);
+ if (error == -EAGAIN)
+ trace_xfs_das_state_return(dac->dela_state);
if (error)
return error;

@@ -1514,6 +1531,7 @@ xfs_attr_node_removename_iter(

dac->flags |= XFS_DAC_DEFER_FINISH;
dac->dela_state = XFS_DAS_RM_SHRINK;
+ trace_xfs_das_state_return(dac->dela_state);
return -EAGAIN;
}

@@ -1532,8 +1550,10 @@ xfs_attr_node_removename_iter(
goto out;
}

- if (error == -EAGAIN)
+ if (error == -EAGAIN) {
+ trace_xfs_das_state_return(dac->dela_state);
return error;
+ }
out:
if (state)
xfs_da_state_free(state);
diff --git a/libxfs/xfs_attr_remote.c b/libxfs/xfs_attr_remote.c
index 628ab42..543dd67 100644
--- a/libxfs/xfs_attr_remote.c
+++ b/libxfs/xfs_attr_remote.c
@@ -762,6 +762,7 @@ __xfs_attr_rmtval_remove(
*/
if (!done) {
dac->flags |= XFS_DAC_DEFER_FINISH;
+ trace_xfs_das_state_return(dac->dela_state);
return -EAGAIN;
}

--
2.7.4