mutex lock can be initialized automatically with DEFINE_MUTEX() rather
than explicitly calling mutex_init().
this patch will reduce the size of bcache.ko about 16 bytes, the reason
as follows:
though this patch will increase the size of .data segment about 32 bytes,
it will also reduce the size of .init.text and .rodata.str1.1(at x86_64),
.rodata_str1.8(at arm64) and .bss segment total about 48 bytes which reduce
the size more than .data segment;
here is the statistics:
Sections: (arm64 platform)
Idx name size
-.init.text 00000240
+.init.text 00000228
-.rodata.str1.8 000012cd
+.rodata.str1.8 000012b5
-.data 00000c60
+.data 00000c80
Sections: (x86 platform)
Idx name size
-.init.text 000001d9
+.init.text 000001bf
-.rodata.str1.1 00000c80
+.rodata.str1.1 00000c6d
-.data 00000cc0
+.data 00000ce0
Reported-by: Hulk Robot <hulkci@xxxxxxxxxx>
Signed-off-by: Zheng Yongjun <zhengyongjun3@xxxxxxxxxx>
---
v3:
- change commit log, delete statistic about .bss segment.
v2:
- add commit log about the reason why bcache.ko size reduced.
drivers/md/bcache/super.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
index 03e1fe4de53d..3635f454309e 100644
--- a/drivers/md/bcache/super.c
+++ b/drivers/md/bcache/super.c
@@ -40,7 +40,7 @@ static const char invalid_uuid[] = {
};
static struct kobject *bcache_kobj;
-struct mutex bch_register_lock;
+DEFINE_MUTEX(bch_register_lock);
bool bcache_is_reboot;
LIST_HEAD(bch_cache_sets);
static LIST_HEAD(uncached_devices);
@@ -2869,7 +2869,6 @@ static int __init bcache_init(void)
check_module_parameters();
- mutex_init(&bch_register_lock);
init_waitqueue_head(&unregister_wait);
register_reboot_notifier(&reboot);
--
2.25.1
