Hi Konrad, The performance is the same using kmemdup, but we have the following advantages: * code is cleaner * kmemdup adds additional debugging info useful for tracking the real place where memory was allocated [1] [2].
thanks, Daniel. [1] http://lxr.linux.no/#linux+v3.8.2/mm/util.c#L61 [2] http://lxr.linux.no/#linux+v3.8.2/include/linux/slab.h#L363 On Mon, Mar 11, 2013 at 4:54 PM, Konrad Rzeszutek Wilk <[email protected]> wrote: > On Mon, Mar 11, 2013 at 01:23:36PM +0200, Mihnea Dobrescu-Balaur wrote: > > Are there performance improvements to doing it this way? > >> Signed-off-by: Mihnea Dobrescu-Balaur <[email protected]> >> --- >> drivers/block/xen-blkfront.c | 3 +-- >> 1 file changed, 1 insertion(+), 2 deletions(-) >> >> diff --git a/drivers/block/xen-blkfront.c b/drivers/block/xen-blkfront.c >> index c3dae2e..9620644 100644 >> --- a/drivers/block/xen-blkfront.c >> +++ b/drivers/block/xen-blkfront.c >> @@ -1203,11 +1203,10 @@ static int blkif_recover(struct blkfront_info *info) >> int j; >> >> /* Stage 1: Make a safe copy of the shadow state. */ >> - copy = kmalloc(sizeof(info->shadow), >> + copy = kmemdup(info->shadow, sizeof(info->shadow), >> GFP_NOIO | __GFP_REPEAT | __GFP_HIGH); >> if (!copy) >> return -ENOMEM; >> - memcpy(copy, info->shadow, sizeof(info->shadow)); >> >> /* Stage 2: Set up free list. */ >> memset(&info->shadow, 0, sizeof(info->shadow)); >> -- >> 1.7.10.4 >> > _______________________________________________ > Virtualization mailing list > [email protected] > https://lists.linuxfoundation.org/mailman/listinfo/virtualization -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
