On 10/29/2014 10:38 PM, Tejun Heo wrote: > On Wed, Oct 29, 2014 at 05:26:34PM +0800, pang.xun...@zte.com.cn wrote: >> The memset in ida_init() already handles idr, so there's some >> redundancy in the following idr_init(). >> >> This patch removes the memset, and clears ida->free_bitmap instead. >> >> Signed-off-by: pang.xunlei <pang.xun...@zte.com.cn> >> --- >> lib/idr.c | 3 +-- >> 1 file changed, 1 insertion(+), 2 deletions(-) >> >> diff --git a/lib/idr.c b/lib/idr.c >> index e654aeb..bbe5779 100644 >> --- a/lib/idr.c >> +++ b/lib/idr.c >> @@ -1141,8 +1141,7 @@ EXPORT_SYMBOL(ida_simple_remove); >> */ >> void ida_init(struct ida *ida) >> { >> - memset(ida, 0, sizeof(struct ida)); >> idr_init(&ida->idr); >> - >> + ida->free_bitmap = NULL; > > I don't know. Does this matter? If this *really* matters, I'd much > rather have memset(&ida->FIRST_FIELD, 0, sizeof(struct ida) - offset > of FIRST_FIELD) to ensure that all fields get reset or implement an > internal function like __idr_init_without_zeroing(); however, given > the size of an idr and the low frequency of the operation, I'd prefer > to just leave it as-is. >
memset(ptr, 0, sizeof()) or kzalloc() is convenient and good for buffers but bad for structures, objects... general way for object initialization is: xxx_init() { explicitly init every field... /* maybe complicated, over elaborate */ } -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/