Thu, Mar 21, 2019 at 02:17:41PM CET, [email protected] wrote: >Without rtnl lock protection tcf proto can be deleted concurrently. Check >tcf proto 'deleting' flag after taking tcf spinlock to verify that no >concurrent deletion is in progress. Return EAGAIN error if concurrent >deletion detected, which will cause caller to retry and possibly create new >instance of tcf proto. > >Retry mechanism is a result of fine-grained locking approach used in this >and previous changes in series and is necessary to allow concurrent updates >on same chain instance. Alternative approach would be to lock the whole >chain while updating filters on any of child tp's, adding and removing >classifier instances from the chain. However, since most CPU-intensive >parts of filter update code are specifically in classifier code and its >dependencies (extensions and hw offloads), such approach would negate most >of the gains introduced by this change and previous changes in the series >when updating same chain instance. > >Signed-off-by: Vlad Buslov <[email protected]> >Reviewed-by: Stefano Brivio <[email protected]>
Acked-by: Jiri Pirko <[email protected]>
