From: Andi Kleen <ak@xxxxxxxxxxxxxxx> Subject: kref: remove WARN_ON for NULL release functions The kref functions check for NULL release functions. This WARN_ON seems rather pointless. We will eventually release and then just crash nicely. It is also somewhat expensive because these functions are inlined in a lot of places. Removing the WARN_ONs saves around 2.3k in this kernel (likely more in others with more drivers) text data bss dec hex filename 9083992 5367600 11116544 25568136 1862388 vmlinux-before-load-avg 9070166 5367600 11116544 25554310 185ed86 vmlinux-load-avg Link: http://lkml.kernel.org/r/20170315021431.13107-5-andi@xxxxxxxxxxxxxx Signed-off-by: Andi Kleen <ak@xxxxxxxxxxxxxxx> Acked-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- include/linux/kref.h | 6 ------ 1 file changed, 6 deletions(-) diff -puN include/linux/kref.h~kref-remove-warn_on-for-null-release-functions include/linux/kref.h --- a/include/linux/kref.h~kref-remove-warn_on-for-null-release-functions +++ a/include/linux/kref.h @@ -66,8 +66,6 @@ static inline void kref_get(struct kref */ static inline int kref_put(struct kref *kref, void (*release)(struct kref *kref)) { - WARN_ON(release == NULL); - if (refcount_dec_and_test(&kref->refcount)) { release(kref); return 1; @@ -79,8 +77,6 @@ static inline int kref_put_mutex(struct void (*release)(struct kref *kref), struct mutex *lock) { - WARN_ON(release == NULL); - if (refcount_dec_and_mutex_lock(&kref->refcount, lock)) { release(kref); return 1; @@ -92,8 +88,6 @@ static inline int kref_put_lock(struct k void (*release)(struct kref *kref), spinlock_t *lock) { - WARN_ON(release == NULL); - if (refcount_dec_and_lock(&kref->refcount, lock)) { release(kref); return 1; _ -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
