From 1e052be69d045c8d0f82ff1116fd3e5a79661745 Mon Sep 17 00:00:00 2001 From: Cong Wang Date: Fri, 6 Mar 2015 11:47:59 -0800 Subject: net_sched: destroy proto tp when all filters are gone Kernel automatically creates a tp for each (kind, protocol, priority) tuple, which has handle 0, when we add a new filter, but it still is left there after we remove our own, unless we don't specify the handle (literally means all the filters under the tuple). For example this one is left: # tc filter show dev eth0 filter parent 8001: protocol arp pref 49152 basic The user-space is hard to clean up these for kernel because filters like u32 are organized in a complex way. So kernel is responsible to remove it after all filters are gone. Each type of filter has its own way to store the filters, so each type has to provide its way to check if all filters are gone. Cc: Jamal Hadi Salim Signed-off-by: Cong Wang Signed-off-by: Cong Wang Acked-by: Jamal Hadi Salim Signed-off-by: David S. Miller --- net/sched/cls_cgroup.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) (limited to 'net/sched/cls_cgroup.c') diff --git a/net/sched/cls_cgroup.c b/net/sched/cls_cgroup.c index 221697ab0247..ea611b216412 100644 --- a/net/sched/cls_cgroup.c +++ b/net/sched/cls_cgroup.c @@ -143,14 +143,18 @@ errout: return err; } -static void cls_cgroup_destroy(struct tcf_proto *tp) +static bool cls_cgroup_destroy(struct tcf_proto *tp, bool force) { struct cls_cgroup_head *head = rtnl_dereference(tp->root); + if (!force) + return false; + if (head) { RCU_INIT_POINTER(tp->root, NULL); call_rcu(&head->rcu, cls_cgroup_destroy_rcu); } + return true; } static int cls_cgroup_delete(struct tcf_proto *tp, unsigned long arg) -- cgit v1.2.3-59-g8ed1b