On Thu, 2012-12-13 at 11:39 +0100, Roger Pau Monne wrote: > Signed-off-by: Roger Pau Monné <[email protected]> > Cc: Huang Ying <[email protected]> > Cc: Konrad Rzeszutek Wilk <[email protected]>
Reviewed-by: Huang Ying <[email protected]> > --- > Changes since v3: > * Change n to use type *, to keep the same semantics as > list_for_each_entry_safe. > Changes since v2: > * Allow to pass a NULL node as the first entry of deleted list > entries. > --- > include/linux/llist.h | 29 +++++++++++++++++++++++++++++ > 1 files changed, 29 insertions(+), 0 deletions(-) > > diff --git a/include/linux/llist.h b/include/linux/llist.h > index a5199f6..f551ac4 100644 > --- a/include/linux/llist.h > +++ b/include/linux/llist.h > @@ -125,6 +125,35 @@ static inline void init_llist_head(struct llist_head > *list) > (pos) = llist_entry((pos)->member.next, typeof(*(pos)), member)) > > /** > + * llist_for_each_entry_safe - safely iterate over some deleted entries of > + * lock-less list of given type > + * @pos: the type * to use as a loop cursor. > + * @n: another type * to use as temporary storage > + * @node: the fist entry of deleted list entries. > + * @member: the name of the llist_node with the struct. > + * > + * In general, some entries of the lock-less list can be traversed > + * safely only after being removed from list, so start with an entry > + * instead of list head. > + * > + * If being used on entries deleted from lock-less list directly, the > + * traverse order is from the newest to the oldest added entry. If > + * you want to traverse from the oldest to the newest, you must > + * reverse the order by yourself before traversing. > + * > + * n is used to store a reference to the next item llist_node, so > + * pos can be freed while iterating. > + */ > +#define llist_for_each_entry_safe(pos, n, node, member) \ > + for ((pos) = llist_entry((node), typeof(*(pos)), member), \ > + (n) = llist_entry(((&(pos)->member != NULL) ? \ > + (pos)->member.next : NULL), typeof(*(pos)), member); \ > + &(pos)->member != NULL; \ > + (pos) = n, \ > + (n) = llist_entry(((&(pos)->member != NULL) ? \ > + (pos)->member.next : NULL), typeof(*(pos)), member)) > + > +/** > * llist_empty - tests whether a lock-less list is empty > * @head: the list to test > * -- 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/
