Wed, Apr 19, 2017 at 03:11:26PM CEST, [email protected] wrote: >On 17-04-19 08:53 AM, Jiri Pirko wrote: >> Wed, Apr 19, 2017 at 01:57:30PM CEST, [email protected] wrote: >> > From: Jamal Hadi Salim <[email protected]> >> > >> > This adds support for filtering based on time since last used. >> > When we are dumping a large number of actions it is useful to >> > have the option of filtering based on when the action was last >> > used to reduce the amount of data crossing to user space. >> > >> > With this patch the user space app sets the TCAA_ACT_TIME_FILTER >> > attribute with the value in milliseconds with "time of interest >> > since now". The kernel converts this to jiffies and does the >> > filtering comparison matching entries that have seen activity >> > since then and returns them to user space. >> > Old kernels and old tc continue to work in legacy mode since >> > they dont specify this attribute. >> > >> > Some example (we have 400 actions bound to 400 filters); at installation >> > time using hacked tc which sets the time of interest to 120 seconds: >> > >> > prompt$ hackedtc actions ls action gact | grep index | wc -l >> > 400 >> > >> > go get some coffee and wait for > 120 seconds and try again: >> > >> > prompt$ hackedtc actions ls action gact | grep index | wc -l >> > 0 >> > >> > Lets see a filter bound to one of these actions: >> > .. >> > filter pref 10 u32 >> > filter pref 10 u32 fh 800: ht divisor 1 >> > filter pref 10 u32 fh 800::800 order 2048 key ht 800 bkt 0 flowid 1:10 >> > (rule hit 2 success 1) >> > match 7f000002/ffffffff at 12 (success 1 ) >> > action order 1: gact action pass >> > random type none pass val 0 >> > index 23 ref 2 bind 1 installed 1145 sec used 802 sec >> > Action statistics: >> > Sent 84 bytes 1 pkt (dropped 0, overlimits 0 requeues 0) >> > backlog 0b 0p requeues 0 >> > .... >> > >> > that coffee took long, no? It was good. >> > >> > Now lets ping -c 1 127.0.0.2, then run the actions again: >> > >> > prompt$ hackedtc actions ls action gact | grep index | wc -l >> > 1 >> > >> > More details please: >> > >> > prompt$ hackedtc -s actions ls action gact >> >> I don't see where you pass the time. >> > >User space sets the TCAA_ACT_TIME_FILTER value. >Jiri - this is described in the commit log ;-> >I have some tc changes which set this value. >In the example below it was 120 seconds.
So it is hard coded. That confused me. I believe it would be good to provide actual tc patch that does the proper changes and include the example of that usage in the description - instead of "hackedtc" > > >> >> > >> > action order 0: gact action pass >> > random type none pass val 0 >> > index 23 ref 2 bind 1 installed 1270 sec used 30 sec >> > Action statistics: >> > Sent 168 bytes 2 pkt (dropped 0, overlimits 0 requeues 0) >> > backlog 0b 0p requeues 0 >> > >> > And the filter? >> > >> > filter pref 10 u32 >> > filter pref 10 u32 fh 800: ht divisor 1 >> > filter pref 10 u32 fh 800::800 order 2048 key ht 800 bkt 0 flowid 1:10 >> > (rule hit 4 success 2) >> > match 7f000002/ffffffff at 12 (success 2 ) >> > action order 1: gact action pass >> > random type none pass val 0 >> > index 23 ref 2 bind 1 installed 1324 sec used 84 sec >> > Action statistics: >> > Sent 168 bytes 2 pkt (dropped 0, overlimits 0 requeues 0) >> > backlog 0b 0p requeues 0 >> > >> > Signed-off-by: Jamal Hadi Salim <[email protected]> >> > --- >> > include/uapi/linux/rtnetlink.h | 1 + >> > net/sched/act_api.c | 25 +++++++++++++++++++++++-- >> > 2 files changed, 24 insertions(+), 2 deletions(-) >> > >> > diff --git a/include/uapi/linux/rtnetlink.h >> > b/include/uapi/linux/rtnetlink.h >> > index c7080ec..1b36cc0 100644 >> > --- a/include/uapi/linux/rtnetlink.h >> > +++ b/include/uapi/linux/rtnetlink.h >> > @@ -680,6 +680,7 @@ enum { >> > TCAA_ACT_TAB, >> > TCAA_ACT_FLAGS, >> > TCAA_ACT_COUNT, >> > + TCAA_ACT_TIME_FILTER, >> >> Another use of word "filter" for something else. I believe that we need >> to reduce confusion, not to make it worse. >> > >It is a time filter. What do you want to call it? TIME_DELTA? > > >> >> > __TCAA_MAX >> > }; >> > >> > diff --git a/net/sched/act_api.c b/net/sched/act_api.c >> > index 45e1cf7..b03863a 100644 >> > --- a/net/sched/act_api.c >> > +++ b/net/sched/act_api.c >> > @@ -84,11 +84,12 @@ static int tcf_dump_walker(struct tcf_hashinfo *hinfo, >> > struct sk_buff *skb, >> > { >> > int err = 0, index = -1, i = 0, s_i = 0, n_i = 0; >> > unsigned short act_flags = cb->args[2]; >> > + unsigned long jiffy_filter = cb->args[3]; >> >> call this "jiffy_since" for example >> > >Sure. > > >> >> > struct nlattr *nest; >> > >> > spin_lock_bh(&hinfo->lock); >> > >> > - s_i = cb->args[0]; >> > + s_i = cb->args[4]; >> > >> > for (i = 0; i < (hinfo->hmask + 1); i++) { >> > struct hlist_head *head; >> > @@ -101,6 +102,11 @@ static int tcf_dump_walker(struct tcf_hashinfo >> > *hinfo, struct sk_buff *skb, >> > if (index < s_i) >> > continue; >> > >> > + if (jiffy_filter && >> > + time_after(jiffy_filter, >> > + (unsigned long)p->tcfa_tm.lastuse)) >> > + continue; >> > + >> > nest = nla_nest_start(skb, n_i); >> > if (nest == NULL) >> > goto nla_put_failure; >> > @@ -118,6 +124,9 @@ static int tcf_dump_walker(struct tcf_hashinfo *hinfo, >> > struct sk_buff *skb, >> > } >> > } >> > done: >> > + if (index > 0) >> > + cb->args[4] = index + 1; >> > + >> > spin_unlock_bh(&hinfo->lock); >> > if (n_i) { >> > cb->args[0] += n_i; >> >> You don't use "cb->args[0]" anymore. Why do you need this? > >You are right - will remove this. > >> Just use cb->args[0] instead of 4 >> > >I can do that too. > > >> >> > @@ -1000,6 +1009,7 @@ static int tcf_action_add(struct net *net, struct >> > nlattr *nla, >> > >> > static const struct nla_policy tcaa_policy[TCAA_MAX + 1] = { >> > [TCAA_ACT_FLAGS] = { .type = NLA_U32 }, >> > + [TCAA_ACT_TIME_FILTER] = { .type = NLA_U32 }, >> > }; >> > >> > static int tc_ctl_action(struct sk_buff *skb, struct nlmsghdr *n, >> > @@ -1090,13 +1100,14 @@ static int tc_dump_action(struct sk_buff *skb, >> > struct netlink_callback *cb) >> > struct tcamsg *t = (struct tcamsg *) nlmsg_data(cb->nlh); >> > struct nlattr *kind = NULL; >> > u32 act_flags = 0; >> > + u32 msecs_filter = 0; >> > + unsigned long jiffy_wanted = 0; >> >> Also, "jiffy_since". Same variable, same name please. >> > >np. > >> > >> > ret = nlmsg_parse(cb->nlh, sizeof(struct tcamsg), tcaa, TCAA_MAX, >> > tcaa_policy, NULL); >> > if (ret < 0) >> > return ret; >> > >> > - >> >> This should not be part of this patch. >> > >Will remove. > >> >> > kind = find_dump_kind(tcaa); >> > if (kind == NULL) { >> > pr_info("tc_dump_action: action bad kind\n"); >> > @@ -1110,12 +1121,22 @@ static int tc_dump_action(struct sk_buff *skb, >> > struct netlink_callback *cb) >> > if (tcaa[TCAA_ACT_FLAGS]) >> > act_flags = nla_get_u32(tcaa[TCAA_ACT_FLAGS]); >> > >> > + if (tcaa[TCAA_ACT_TIME_FILTER]) >> > + msecs_filter = nla_get_u32(tcaa[TCAA_ACT_TIME_FILTER]); >> > + >> > nlh = nlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq, >> > cb->nlh->nlmsg_type, sizeof(*t), 0); >> > if (!nlh) >> > goto out_module_put; >> > >> > + if (msecs_filter) { >> > + unsigned long jiffy_msecs = msecs_to_jiffies(msecs_filter); >> > + >> > + jiffy_wanted = jiffies - jiffy_msecs; >> >> you can do just: >> jiffy_wanted = jiffies - msecs_to_jiffies(msecs_filter); >> >> Also, you can put this under "if (tcaa[TCAA_ACT_TIME_FILTER])" so it's >> all in one place. >> > >Will do - next cycle run. Thanks. > > >cheers, >jamal
