[PATCH v22 17/27] xfsprogs: Add state machine tracepoints

[Allison Henderson <allison.henderson@xxxxxxxxxx>]

Source kernel commit: fbc8d6bb875915e0afd8ff6cd4364b368a6f894f

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@xxxxxxxxxx>
Reviewed-by: Darrick J. Wong <djwong@xxxxxxxxxx>
---
 include/xfs_trace.h      |  6 ++++++
 libxfs/xfs_attr.c        | 28 ++++++++++++++++++++++++++--
 libxfs/xfs_attr_remote.c |  1 +
 3 files changed, 33 insertions(+), 2 deletions(-)

diff --git a/include/xfs_trace.h b/include/xfs_trace.h
index a847b50..2169c27 100644
--- a/include/xfs_trace.h
+++ b/include/xfs_trace.h
@@ -312,4 +312,10 @@
 #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_attr_sf_addname_return(a,b)	((void) 0)
+#define trace_xfs_attr_set_iter_return(a,b)	((void) 0)
+#define trace_xfs_attr_node_addname_return(a,b)	((void) 0)
+#define trace_xfs_attr_remove_iter_return(a,b)	((void) 0)
+#define trace_xfs_attr_rmtval_remove_return(a,b)	((void) 0)
+
 #endif /* __TRACE_H__ */
diff --git a/libxfs/xfs_attr.c b/libxfs/xfs_attr.c
index 84b88f9..6380cae 100644
--- a/libxfs/xfs_attr.c
+++ b/libxfs/xfs_attr.c
@@ -335,6 +335,7 @@ xfs_attr_sf_addname(
 	 * the attr fork to leaf format and will restart with the leaf
 	 * add.
 	 */
+	trace_xfs_attr_sf_addname_return(XFS_DAS_UNINIT, args->dp);
 	dac->flags |= XFS_DAC_DEFER_FINISH;
 	return -EAGAIN;
 }
@@ -394,6 +395,8 @@ xfs_attr_set_iter(
 				 * handling code below
 				 */
 				dac->flags |= XFS_DAC_DEFER_FINISH;
+				trace_xfs_attr_set_iter_return(
+					dac->dela_state, args->dp);
 				return -EAGAIN;
 			} else if (error) {
 				return error;
@@ -418,6 +421,7 @@ xfs_attr_set_iter(
 
 			dac->dela_state = XFS_DAS_FOUND_NBLK;
 		}
+		trace_xfs_attr_set_iter_return(dac->dela_state, args->dp);
 		return -EAGAIN;
 	case XFS_DAS_FOUND_LBLK:
 		/*
@@ -445,6 +449,8 @@ xfs_attr_set_iter(
 			error = xfs_attr_rmtval_set_blk(dac);
 			if (error)
 				return error;
+			trace_xfs_attr_set_iter_return(dac->dela_state,
+						       args->dp);
 			return -EAGAIN;
 		}
 
@@ -479,6 +485,7 @@ xfs_attr_set_iter(
 		 * series.
 		 */
 		dac->dela_state = XFS_DAS_FLIP_LFLAG;
+		trace_xfs_attr_set_iter_return(dac->dela_state, args->dp);
 		return -EAGAIN;
 	case XFS_DAS_FLIP_LFLAG:
 		/*
@@ -496,6 +503,9 @@ xfs_attr_set_iter(
 		dac->dela_state = XFS_DAS_RM_LBLK;
 		if (args->rmtblkno) {
 			error = __xfs_attr_rmtval_remove(dac);
+			if (error == -EAGAIN)
+				trace_xfs_attr_set_iter_return(
+					dac->dela_state, args->dp);
 			if (error)
 				return error;
 
@@ -549,6 +559,8 @@ xfs_attr_set_iter(
 				error = xfs_attr_rmtval_set_blk(dac);
 				if (error)
 					return error;
+				trace_xfs_attr_set_iter_return(
+					dac->dela_state, args->dp);
 				return -EAGAIN;
 			}
 
@@ -584,6 +596,7 @@ xfs_attr_set_iter(
 		 * series
 		 */
 		dac->dela_state = XFS_DAS_FLIP_NFLAG;
+		trace_xfs_attr_set_iter_return(dac->dela_state, args->dp);
 		return -EAGAIN;
 
 	case XFS_DAS_FLIP_NFLAG:
@@ -603,6 +616,10 @@ xfs_attr_set_iter(
 		dac->dela_state = XFS_DAS_RM_NBLK;
 		if (args->rmtblkno) {
 			error = __xfs_attr_rmtval_remove(dac);
+			if (error == -EAGAIN)
+				trace_xfs_attr_set_iter_return(
+					dac->dela_state, args->dp);
+
 			if (error)
 				return error;
 
@@ -1183,6 +1200,8 @@ xfs_attr_node_addname(
 			 * this point.
 			 */
 			dac->flags |= XFS_DAC_DEFER_FINISH;
+			trace_xfs_attr_node_addname_return(
+					dac->dela_state, args->dp);
 			return -EAGAIN;
 		}
 
@@ -1429,10 +1448,13 @@ xfs_attr_remove_iter(
 			 * blocks are removed.
 			 */
 			error = __xfs_attr_rmtval_remove(dac);
-			if (error == -EAGAIN)
+			if (error == -EAGAIN) {
+				trace_xfs_attr_remove_iter_return(
+						dac->dela_state, args->dp);
 				return error;
-			else if (error)
+			} else if (error) {
 				goto out;
+			}
 
 			/*
 			 * Refill the state structure with buffers (the prior
@@ -1473,6 +1495,8 @@ xfs_attr_remove_iter(
 
 			dac->flags |= XFS_DAC_DEFER_FINISH;
 			dac->dela_state = XFS_DAS_RM_SHRINK;
+			trace_xfs_attr_remove_iter_return(
+					dac->dela_state, args->dp);
 			return -EAGAIN;
 		}
 
diff --git a/libxfs/xfs_attr_remote.c b/libxfs/xfs_attr_remote.c
index d474ad7..137e569 100644
--- a/libxfs/xfs_attr_remote.c
+++ b/libxfs/xfs_attr_remote.c
@@ -695,6 +695,7 @@ __xfs_attr_rmtval_remove(
 	 */
 	if (!done) {
 		dac->flags |= XFS_DAC_DEFER_FINISH;
+		trace_xfs_attr_rmtval_remove_return(dac->dela_state, args->dp);
 		return -EAGAIN;
 	}
 
-- 
2.7.4