[patch 056/163] mm/swap_slots.c: remove redundant check for swap_slot_cache_initialized

Andrew Morton
2020-08-07T06:20:14Z

From: Zhen Lei <thunder.leizhen@huawei.com>
Subject: mm/swap_slots.c: remove redundant check for swap_slot_cache_initialized

Because enable_swap_slots_cache can only become true in
enable_swap_slots_cache(), and depends on swap_slot_cache_initialized is
true before. That means, when enable_swap_slots_cache is true,
swap_slot_cache_initialized is true also.

So the condition:
"swap_slot_cache_enabled && swap_slot_cache_initialized"
can be reduced to "swap_slot_cache_enabled"

And in mathematics:
"!swap_slot_cache_enabled || !swap_slot_cache_initialized"
is equal to "!(swap_slot_cache_enabled && swap_slot_cache_initialized)"

So no functional change.

Link: http://lkml.kernel.org/r/20200430061143.450-4-thunder.leizhen@huawei.com
Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Acked-by: Tim Chen <tim.c.chen@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

mm/swap_slots.c | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)

--- a/mm/swap_slots.c~mm-swap-remove-redundant-check-for-swap_slot_cache_initialized
+++ a/mm/swap_slots.c
@@ -46,8 +46,7 @@ static void __drain_swap_slots_cache(uns
static void deactivate_swap_slots_cache(void);
static void reactivate_swap_slots_cache(void);

-#define use_swap_slot_cache (swap_slot_cache_active && \
- swap_slot_cache_enabled && swap_slot_cache_initialized)
+#define use_swap_slot_cache (swap_slot_cache_active && swap_slot_cache_enabled)
#define SLOTS_CACHE 0x1
#define SLOTS_CACHE_RET 0x2

@@ -94,7 +93,7 @@ static bool check_cache_active(void)
{
long pages;

- if (!swap_slot_cache_enabled || !swap_slot_cache_initialized)
+ if (!swap_slot_cache_enabled)
return false;

pages = get_nr_swap_pages();
_