[Patch v2 1/2] XArray: make xa_dump output more friendly to read

[Wei Yang <richard.weiyang@gmail.com>]

This patch helps to adjust xa_dump output by:

  * add an index to each entry
  * add indent to each entry

Then the output would look like:

[ 0]0-4095: node ffff938e16539b60 max 19 parent 0000000000000000 shift 6 count 48 values 48 array ffffffffc05e1280 list ffff938e16539b78 ffff938e16539b78 marks 0 0 0
  [ 0]0-63: value 0 (0x0) [0000000000000001]
  [ 1]64-127: sibling (slot 0)
  [ 2]128-191: sibling (slot 0)
  [ 3]192-255: sibling (slot 0)
  [ 4]256-319: sibling (slot 0)
  [ 5]320-383: sibling (slot 0)
  [ 6]384-447: sibling (slot 0)
  [ 7]448-511: sibling (slot 0)
  [ 8]512-575: sibling (slot 0)
  [ 9]576-639: sibling (slot 0)
  [10]640-703: sibling (slot 0)
  [11]704-767: sibling (slot 0)
  [12]768-831: sibling (slot 0)
  [13]832-895: sibling (slot 0)
  [14]896-959: sibling (slot 0)
  [15]960-1023: sibling (slot 0)
  [32]2048-2111: value 2048 (0x800) [0000000000001001]
  [33]2112-2175: sibling (slot 32)
  [34]2176-2239: sibling (slot 32)
  [35]2240-2303: sibling (slot 32)
  [36]2304-2367: sibling (slot 32)
  [37]2368-2431: sibling (slot 32)
  [38]2432-2495: sibling (slot 32)
  [39]2496-2559: sibling (slot 32)
  [40]2560-2623: sibling (slot 32)
  [41]2624-2687: sibling (slot 32)
  [42]2688-2751: sibling (slot 32)
  [43]2752-2815: sibling (slot 32)
  [44]2816-2879: sibling (slot 32)
  [45]2880-2943: sibling (slot 32)
  [46]2944-3007: sibling (slot 32)
  [47]3008-3071: sibling (slot 32)

Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
---
 lib/xarray.c | 16 ++++++++++------
 1 file changed, 10 insertions(+), 6 deletions(-)

diff --git a/lib/xarray.c b/lib/xarray.c
index 1ddcfa8c86ac..ed50a26d97a3 100644
--- a/lib/xarray.c
+++ b/lib/xarray.c
@@ -2235,19 +2235,22 @@ void xa_dump_node(const struct xa_node *node)
 
 void xa_dump_index(unsigned long index, unsigned int shift)
 {
+	pr_cont("[%2lu]", (index >> shift) & XA_CHUNK_MASK);
 	if (!shift)
-		pr_info("%lu: ", index);
+		pr_cont("%lu: ", index);
 	else if (shift >= BITS_PER_LONG)
-		pr_info("0-%lu: ", ~0UL);
+		pr_cont("0-%lu: ", ~0UL);
 	else
-		pr_info("%lu-%lu: ", index, index | ((1UL << shift) - 1));
+		pr_cont("%lu-%lu: ", index, index | ((1UL << shift) - 1));
 }
 
-void xa_dump_entry(const void *entry, unsigned long index, unsigned long shift)
+void xa_dump_entry(const void *entry, unsigned long index, unsigned long shift,
+			int level)
 {
 	if (!entry)
 		return;
 
+	pr_info("%*s", level * 2, level ? " " : "");
 	xa_dump_index(index, shift);
 
 	if (xa_is_node(entry)) {
@@ -2259,7 +2262,8 @@ void xa_dump_entry(const void *entry, unsigned long index, unsigned long shift)
 			xa_dump_node(node);
 			for (i = 0; i < XA_CHUNK_SIZE; i++)
 				xa_dump_entry(node->slots[i],
-				      index + (i << node->shift), node->shift);
+				      index + (i << node->shift), node->shift,
+				      level + 1);
 		}
 	} else if (xa_is_value(entry))
 		pr_cont("value %ld (0x%lx) [%px]\n", xa_to_value(entry),
@@ -2286,6 +2290,6 @@ void xa_dump(const struct xarray *xa)
 			xa_marked(xa, XA_MARK_1), xa_marked(xa, XA_MARK_2));
 	if (xa_is_node(entry))
 		shift = xa_to_node(entry)->shift + XA_CHUNK_SHIFT;
-	xa_dump_entry(entry, 0, shift);
+	xa_dump_entry(entry, 0, shift, 0);
 }
 #endif
-- 
2.33.1