The patch titled kcalloc: remove runtime division has been added to the -mm tree. Its filename is kcalloc-remove-runtime-division.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** See http://www.zip.com.au/~akpm/linux/patches/stuff/added-to-mm.txt to find out what to do about this The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/ ------------------------------------------------------ Subject: kcalloc: remove runtime division From: Milton Miller <miltonm@xxxxxxx> While in all cases in the kernel we know the size of the elements to be created, we don't always know the count of elements. By commuting the size and count in the overflow check, the compiler can reduce the runtime division of size_t with a compare to a (unique) constant in these cases. Signed-off-by: Milton Miller <miltonm@xxxxxxx> Cc: Takashi Iwai <tiwai@xxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- include/linux/slab.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff -puN include/linux/slab.h~kcalloc-remove-runtime-division include/linux/slab.h --- a/include/linux/slab.h~kcalloc-remove-runtime-division +++ a/include/linux/slab.h @@ -187,7 +187,7 @@ size_t ksize(const void *); */ static inline void *kcalloc(size_t n, size_t size, gfp_t flags) { - if (n != 0 && size > ULONG_MAX / n) + if (size != 0 && n > ULONG_MAX / size) return NULL; return __kmalloc(n * size, flags | __GFP_ZERO); } _ Patches currently in -mm which might be from miltonm@xxxxxxx are alsa-correct-kcalloc-usage.patch pci-dynidsuse_driver_data-considered-harmful.patch kcalloc-remove-runtime-division.patch -- 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