[PATCH] fgraph: Remove unused FGRAPH_MAX_INDEX

FGRAPH_MAX_INDEX has no user, and it expands to FGRAPH_INDEX_SIZE and
FGRAPH_RET_INDEX, neither of which is defined anywhere in the tree. It
was added in that form by commit 91c46b0aa917 ("function_graph:
Implement fgraph_reserve_data() and fgraph_retrieve_data()"), which
introduced the current data word layout under new names, so anything
referencing it would have failed to build ever since.

Remove it.

Signed-off-by: Donggeun Yoo <redacted>
---
Found while reading the shadow stack word layout. The macro is dead in
both senses: nothing references it, and it could not be used as it is.

Compile-tested only, with CONFIG_FUNCTION_GRAPH_TRACER=y and
CONFIG_DYNAMIC_FTRACE=y. Removing an unreferenced macro cannot change
generated code, so there is nothing to test at run time.

 kernel/trace/fgraph.c | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/kernel/trace/fgraph.c b/kernel/trace/fgraph.c
index 40d373d65f9b..ed455b53513b 100644
--- a/kernel/trace/fgraph.c
+++ b/kernel/trace/fgraph.c

@@ -143,9 +143,6 @@ enum {
 #define FGRAPH_DATA_INDEX_MASK	GENMASK(FGRAPH_DATA_INDEX_BITS - 1, 0)
 #define FGRAPH_DATA_INDEX_SHIFT	(FGRAPH_DATA_SHIFT + FGRAPH_DATA_BITS)
 
-#define FGRAPH_MAX_INDEX	\
-	((FGRAPH_INDEX_SIZE << FGRAPH_DATA_BITS) + FGRAPH_RET_INDEX)
-
 #define FGRAPH_ARRAY_SIZE	FGRAPH_INDEX_BITS
 
 /*

-- 
2.53.0