For some reason the attribute is called __attribute_const__ and not
__const, marks functions that have no observable effects on program
state, IOW not reading pointers, just the arguments and calculating a
value. Allows the compiler to do some optimizations, based on
-Wsuggest-attribute=const . The effects are rather small, though, about
60 bytes decrese of btrfs.ko.
Signed-off-by: David Sterba <dste...@suse.com>
---
fs/btrfs/ctree.h | 2 +-
fs/btrfs/super.c | 2 +-
fs/btrfs/volumes.c | 2 +-
fs/btrfs/volumes.h | 2 +-
4 files changed, 4 insertions(+), 4 deletions(-)
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 4bf0433b1179..793085770c84 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -3146,7 +3146,7 @@ __cold
void __btrfs_handle_fs_error(struct btrfs_fs_info *fs_info, const char
*function,
unsigned int line, int errno, const char *fmt, ...);
-const char *btrfs_decode_error(int errno);
+const char * __attribute_const__ btrfs_decode_error(int errno);
__cold
void __btrfs_abort_transaction(struct btrfs_trans_handle *trans,
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 3da35d8b21a3..b3e6d7aa3402 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -66,7 +66,7 @@ static struct file_system_type btrfs_root_fs_type;
static int btrfs_remount(struct super_block *sb, int *flags, char *data);
-const char *btrfs_decode_error(int errno)
+const char * __attribute_const__ btrfs_decode_error(int errno)
{
char *errstr = "unknown";
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 3fd89aee539d..c343b7cdfb53 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -297,7 +297,7 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info,
DEFINE_MUTEX(uuid_mutex);
static LIST_HEAD(fs_uuids);
-struct list_head *btrfs_get_fs_uuids(void)
+struct list_head * __attribute_const__ btrfs_get_fs_uuids(void)
{
return &fs_uuids;
}
diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h
index a7da1f3e3627..0ae0677a8d86 100644
--- a/fs/btrfs/volumes.h
+++ b/fs/btrfs/volumes.h
@@ -571,7 +571,7 @@ static inline enum btrfs_raid_types
btrfs_bg_flags_to_raid_index(u64 flags)
void btrfs_commit_device_sizes(struct btrfs_transaction *trans);
-struct list_head *btrfs_get_fs_uuids(void);
+struct list_head * __attribute_const__ btrfs_get_fs_uuids(void);
void btrfs_set_fs_info_ptr(struct btrfs_fs_info *fs_info);
void btrfs_reset_fs_info_ptr(struct btrfs_fs_info *fs_info);
bool btrfs_check_rw_degradable(struct btrfs_fs_info *fs_info,
--
2.23.0
