On Fri, Oct 20, 2017 at 8:32 PM, Pravin Shelar <pshe...@ovn.org> wrote:
> On Thu, Oct 19, 2017 at 5:58 PM, Andy Zhou <az...@ovn.org> wrote:
>>
>> On Thu, Oct 19, 2017 at 02:47 Pravin Shelar <pshe...@ovn.org> wrote:
>>>
>>> On Tue, Oct 17, 2017 at 12:36 AM, Andy Zhou <az...@ovn.org> wrote:
>>> > OVS kernel datapath so far does not support Openflow meter action.
>>> > This is the first stab at adding kernel datapath meter support.
>>> > This implementation supports only drop band type.
>>> >
>>> > Signed-off-by: Andy Zhou <az...@ovn.org>
>>> > ---
>>> > net/openvswitch/Makefile | 1 +
>>> > net/openvswitch/datapath.c | 14 +-
>>> > net/openvswitch/datapath.h | 3 +
>>> > net/openvswitch/meter.c | 604
>>> > +++++++++++++++++++++++++++++++++++++++++++++
>>> > net/openvswitch/meter.h | 54 ++++
>>> > 5 files changed, 674 insertions(+), 2 deletions(-)
>>> > create mode 100644 net/openvswitch/meter.c
>>> > create mode 100644 net/openvswitch/meter.h
>>> >
>>> This patch mostly looks good. I have one comment below.
>>>
>>> > +static int ovs_meter_cmd_set(struct sk_buff *skb, struct genl_info
>>> > *info)
>>> > +{
>>> > + struct nlattr **a = info->attrs;
>>> > + struct dp_meter *meter, *old_meter;
>>> > + struct sk_buff *reply;
>>> > + struct ovs_header *ovs_reply_header;
>>> > + struct ovs_header *ovs_header = info->userhdr;
>>> > + struct datapath *dp;
>>> > + int err;
>>> > + u32 meter_id;
>>> > + bool failed;
>>> > +
>>> > + meter = dp_meter_create(a);
>>> > + if (IS_ERR_OR_NULL(meter))
>>> > + return PTR_ERR(meter);
>>> > +
>>> > + reply = ovs_meter_cmd_reply_start(info, OVS_METER_CMD_SET,
>>> > + &ovs_reply_header);
>>> > + if (IS_ERR(reply)) {
>>> > + err = PTR_ERR(reply);
>>> > + goto exit_free_meter;
>>> > + }
>>> > +
>>> > + ovs_lock();
>>> > + dp = get_dp(sock_net(skb->sk), ovs_header->dp_ifindex);
>>> > + if (!dp) {
>>> > + err = -ENODEV;
>>> > + goto exit_unlock;
>>> > + }
>>> > +
>>> > + if (!a[OVS_METER_ATTR_ID]) {
>>> > + err = -ENODEV;
>>> > + goto exit_unlock;
>>> > + }
>>> > +
>>> > + meter_id = nla_get_u32(a[OVS_METER_ATTR_ID]);
>>> > +
>>> > + /* Cannot fail after this. */
>>> > + old_meter = lookup_meter(dp, meter_id);
>>> I do not see RCU read lock taken here. This is not correctness issue
>>> but it could cause RCU checker to spit out warning message. You could
>>> do same trick that is done in get_dp() to avoid this issue.
>>
>> O.K.
>>>
>>>
>>>
>>> Can you also test the code with rcu sparse check config option enabled?
>>
>>
>> Do you mean to sparse compile with CONFIG_PROVE_LOCKING and
>> CONFIG_DENUG_OBJECTS_RCU_HEAD?
>
> You could use all following options simultaneously:
> CONFIG_PREEMPT
> CONFIG_DEBUG_PREEMPT
> CONFIG_DEBUG_SPINLOCK
> CONFIG_DEBUG_ATOMIC_SLEEP
> CONFIG_PROVE_RCU
> CONFIG_DEBUG_OBJECTS_RCU_HEAD
Thanks, I turned on those flags but did not get any error message. Do you
mind share the RCU checker message?
