[for-next][PATCH 06/16] tracing: Remove lookups from tracing_map hitcount

From: Steven Rostedt
Date: Fri Oct 06 2017 - 14:10:57 EST


From: Tom Zanussi <tom.zanussi@xxxxxxxxxxxxxxx>

Lookups inflate the hitcount, making it essentially useless. Only
inserts and updates should really affect the hitcount anyway, so
explicitly filter lookups out.

Link: http://lkml.kernel.org/r/c8d9dc39d269a8abf88bf4102d0dfc65deb0fc7f.1506105045.git.tom.zanussi@xxxxxxxxxxxxxxx

Signed-off-by: Tom Zanussi <tom.zanussi@xxxxxxxxxxxxxxx>
Signed-off-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
---
kernel/trace/tracing_map.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/kernel/trace/tracing_map.c b/kernel/trace/tracing_map.c
index 305039b122fa..07e75344725b 100644
--- a/kernel/trace/tracing_map.c
+++ b/kernel/trace/tracing_map.c
@@ -428,7 +428,8 @@ __tracing_map_insert(struct tracing_map *map, void *key, bool lookup_only)

if (test_key && test_key == key_hash && entry->val &&
keys_match(key, entry->val->key, map->key_size)) {
- atomic64_inc(&map->hits);
+ if (!lookup_only)
+ atomic64_inc(&map->hits);
return entry->val;
}

--
2.13.2