| Message ID | 44bec1b2-b961-ff13-374d-57b7adf5e3fd@suse.com (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
On Wed, Sep 21, 2016 at 12:17:37PM -0400, Jeff Mahoney wrote: > We can hit unused variable warnings when btrfs_debug and friends are > just aliases for no_printk. This is due to the fs_info not getting > consumed by the function call, which can happen if convenenience > variables are used. This patch adds a new btrfs_no_printk static inline > that consumes the convenience variable and does nothing else. It > silences the unused variable warning and has no impact on the generated > code: > > $ size fs/btrfs/extent_io.o* > text data bss dec hex filename > 44072 152 32 44256 ace0 fs/btrfs/extent_io.o.btrfs_no_printk > 44072 152 32 44256 ace0 fs/btrfs/extent_io.o.no_printk > > Fixes: 27a0dd61a5 (Btrfs: make btrfs_debug match pr_debug handling related to DEBUG) > Signed-off-by: Jeff Mahoney <jeffm@suse.com> Looks good, aded to the queue. -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index b967af5..e51ee72 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -3241,6 +3241,12 @@ int btrfs_sync_fs(struct super_block *sb, int wait); #ifdef CONFIG_PRINTK __printf(2, 3) void btrfs_printk(const struct btrfs_fs_info *fs_info, const char *fmt, ...); +__printf(2, 3) +static inline int btrfs_no_printk(const struct btrfs_fs_info *fs_info, + const char *fmt, ...) +{ + return 0; +} #else static inline __printf(2, 3) void btrfs_printk(const struct btrfs_fs_info *fs_info, const char *fmt, ...) @@ -3355,13 +3361,13 @@ do { \ btrfs_printk_ratelimited(fs_info, KERN_DEBUG fmt, ##args) #else #define btrfs_debug(fs_info, fmt, args...) \ - no_printk(KERN_DEBUG fmt, ##args) + btrfs_no_printk(fs_info, KERN_DEBUG fmt, ##args) #define btrfs_debug_in_rcu(fs_info, fmt, args...) \ - no_printk(KERN_DEBUG fmt, ##args) + btrfs_no_printk(fs_info, KERN_DEBUG fmt, ##args) #define btrfs_debug_rl_in_rcu(fs_info, fmt, args...) \ - no_printk(KERN_DEBUG fmt, ##args) + btrfs_no_printk(fs_info, KERN_DEBUG fmt, ##args) #define btrfs_debug_rl(fs_info, fmt, args...) \ - no_printk(KERN_DEBUG fmt, ##args) + btrfs_no_printk(fs_info, KERN_DEBUG fmt, ##args) #endif #define btrfs_printk_in_rcu(fs_info, fmt, args...) \
We can hit unused variable warnings when btrfs_debug and friends are just aliases for no_printk. This is due to the fs_info not getting consumed by the function call, which can happen if convenenience variables are used. This patch adds a new btrfs_no_printk static inline that consumes the convenience variable and does nothing else. It silences the unused variable warning and has no impact on the generated code: $ size fs/btrfs/extent_io.o* text data bss dec hex filename 44072 152 32 44256 ace0 fs/btrfs/extent_io.o.btrfs_no_printk 44072 152 32 44256 ace0 fs/btrfs/extent_io.o.no_printk Fixes: 27a0dd61a5 (Btrfs: make btrfs_debug match pr_debug handling related to DEBUG) Signed-off-by: Jeff Mahoney <jeffm@suse.com> --- fs/btrfs/ctree.h | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-)