| Message ID | 20201016144205.21787-3-vladbu@nvidia.com (mailing list archive) |
|---|---|
| State | Not Applicable |
| Headers | show |
| Series | Implement filter terse dump mode support | expand |
On 2020-10-16 10:42 a.m., Vlad Buslov wrote: > From: Vlad Buslov <vladbu@mellanox.com> > > Implement support for classifier/action terse dump using new TCA_DUMP_FLAGS > tlv with only available flag value TCA_DUMP_FLAGS_TERSE. Set the flag when > user requested it with following example CLI (-br for 'brief'): > > $ tc -s -brief filter show dev ens1f0 ingress > filter protocol all pref 49151 flower chain 0 > filter protocol all pref 49151 flower chain 0 handle 0x1 > not_in_hw > action order 1: Action statistics: > Sent 0 bytes 0 pkt (dropped 0, overlimits 0 requeues 0) > backlog 0b 0p requeues 0 > > filter protocol all pref 49152 flower chain 0 > filter protocol all pref 49152 flower chain 0 handle 0x1 > not_in_hw > action order 1: Action statistics: > Sent 0 bytes 0 pkt (dropped 0, overlimits 0 requeues 0) > backlog 0b 0p requeues 0 > Should the action name at least show up? cheers, jamal
On Fri 16 Oct 2020 at 19:07, Jamal Hadi Salim <jhs@mojatatu.com> wrote: > On 2020-10-16 10:42 a.m., Vlad Buslov wrote: >> From: Vlad Buslov <vladbu@mellanox.com> >> >> Implement support for classifier/action terse dump using new TCA_DUMP_FLAGS >> tlv with only available flag value TCA_DUMP_FLAGS_TERSE. Set the flag when >> user requested it with following example CLI (-br for 'brief'): >> >> $ tc -s -brief filter show dev ens1f0 ingress >> filter protocol all pref 49151 flower chain 0 >> filter protocol all pref 49151 flower chain 0 handle 0x1 >> not_in_hw >> action order 1: Action statistics: >> Sent 0 bytes 0 pkt (dropped 0, overlimits 0 requeues 0) >> backlog 0b 0p requeues 0 >> >> filter protocol all pref 49152 flower chain 0 >> filter protocol all pref 49152 flower chain 0 handle 0x1 >> not_in_hw >> action order 1: Action statistics: >> Sent 0 bytes 0 pkt (dropped 0, overlimits 0 requeues 0) >> backlog 0b 0p requeues 0 >> > > Should the action name at least show up? > > > cheers, > jamal All action print callbacks have arg==NULL check and return at the beginning. To print action type we need either to have dedicated 'brief_dump' callback instead of reusing print_aop() or extend/refactor print_aop() implementation for all actions to always print the type before checking the arg. What do you suggest?
On 2020-10-16 12:42 p.m., Vlad Buslov wrote: > > All action print callbacks have arg==NULL check and return at the > beginning. To print action type we need either to have dedicated > 'brief_dump' callback instead of reusing print_aop() or extend/refactor > print_aop() implementation for all actions to always print the type > before checking the arg. What do you suggest? > Either one sounds appealing - the refactoring feels simpler as opposed to a->terse_print(). BTW: the action index, unless i missed something, is not transported from the kernel for terse option. It is an important parameter when actions are shared by filters (since they will have the same index). Am i missing something? cheers, jamal
On Sat 17 Oct 2020 at 14:20, Jamal Hadi Salim <jhs@mojatatu.com> wrote: > On 2020-10-16 12:42 p.m., Vlad Buslov wrote: > >> >> All action print callbacks have arg==NULL check and return at the >> beginning. To print action type we need either to have dedicated >> 'brief_dump' callback instead of reusing print_aop() or extend/refactor >> print_aop() implementation for all actions to always print the type >> before checking the arg. What do you suggest? >> > > Either one sounds appealing - the refactoring feels simpler > as opposed to a->terse_print(). With such refactoring we action type will be printed before some basic validation which can lead to outputting the type together with error message. Consider tunnel key action output callback as example: static int print_tunnel_key(struct action_util *au, FILE *f, struct rtattr *arg) { struct rtattr *tb[TCA_TUNNEL_KEY_MAX + 1]; struct tc_tunnel_key *parm; if (!arg) return 0; parse_rtattr_nested(tb, TCA_TUNNEL_KEY_MAX, arg); if (!tb[TCA_TUNNEL_KEY_PARMS]) { fprintf(stderr, "Missing tunnel_key parameters\n"); return -1; } parm = RTA_DATA(tb[TCA_TUNNEL_KEY_PARMS]); print_string(PRINT_ANY, "kind", "%s ", "tunnel_key"); If print "kind" call is moved before checking the arg it will always be printed, even when immediately followed by "Missing tunnel_key parameters\n" string. Is this a concern? > > BTW: the action index, unless i missed something, is not transported > from the kernel for terse option. It is an important parameter > when actions are shared by filters (since they will have the same > index). > Am i missing something? Yes, tc_action_ops->dump(), which outputs action index among other data, is not called at all by terse dump. > > cheers, > jamal
On 2020-10-18 8:16 a.m., Vlad Buslov wrote: > On Sat 17 Oct 2020 at 14:20, Jamal Hadi Salim <jhs@mojatatu.com> wrote: >> On 2020-10-16 12:42 p.m., Vlad Buslov wrote: >> >> Either one sounds appealing - the refactoring feels simpler >> as opposed to a->terse_print(). > > With such refactoring we action type will be printed before some basic > validation which can lead to outputting the type together with error > message. Consider tunnel key action output callback as example: > > static int print_tunnel_key(struct action_util *au, FILE *f, struct rtattr *arg) > { > struct rtattr *tb[TCA_TUNNEL_KEY_MAX + 1]; > struct tc_tunnel_key *parm; > > if (!arg) > return 0; > > parse_rtattr_nested(tb, TCA_TUNNEL_KEY_MAX, arg); > > if (!tb[TCA_TUNNEL_KEY_PARMS]) { > fprintf(stderr, "Missing tunnel_key parameters\n"); > return -1; > } > parm = RTA_DATA(tb[TCA_TUNNEL_KEY_PARMS]); > > print_string(PRINT_ANY, "kind", "%s ", "tunnel_key"); > > If print "kind" call is moved before checking the arg it will always be > printed, even when immediately followed by "Missing tunnel_key > parameters\n" string. Is this a concern? > That could be a good thing, no? you get to see the action name with the error. Its really not a big deal if you decide to do a->terse_print() instead. >> >> BTW: the action index, unless i missed something, is not transported >> from the kernel for terse option. It is an important parameter >> when actions are shared by filters (since they will have the same >> index). >> Am i missing something? > > Yes, tc_action_ops->dump(), which outputs action index among other data, > is not called at all by terse dump. I am suggesting it is an important detail that is currently missing. Alternatively since you have the cookies in there - it is feasible that someone who creates the action could "encode" the index in the cookie. But that makes it a "proprietary" choice of whoever is creating the filter/action. cheers, jamal
On Mon 19 Oct 2020 at 16:48, Jamal Hadi Salim <jhs@mojatatu.com> wrote: > On 2020-10-18 8:16 a.m., Vlad Buslov wrote: >> On Sat 17 Oct 2020 at 14:20, Jamal Hadi Salim <jhs@mojatatu.com> wrote: >>> On 2020-10-16 12:42 p.m., Vlad Buslov wrote: >>> > >>> Either one sounds appealing - the refactoring feels simpler >>> as opposed to a->terse_print(). >> >> With such refactoring we action type will be printed before some basic >> validation which can lead to outputting the type together with error >> message. Consider tunnel key action output callback as example: >> >> static int print_tunnel_key(struct action_util *au, FILE *f, struct rtattr *arg) >> { >> struct rtattr *tb[TCA_TUNNEL_KEY_MAX + 1]; >> struct tc_tunnel_key *parm; >> >> if (!arg) >> return 0; >> >> parse_rtattr_nested(tb, TCA_TUNNEL_KEY_MAX, arg); >> >> if (!tb[TCA_TUNNEL_KEY_PARMS]) { >> fprintf(stderr, "Missing tunnel_key parameters\n"); >> return -1; >> } >> parm = RTA_DATA(tb[TCA_TUNNEL_KEY_PARMS]); >> >> print_string(PRINT_ANY, "kind", "%s ", "tunnel_key"); >> >> If print "kind" call is moved before checking the arg it will always be >> printed, even when immediately followed by "Missing tunnel_key >> parameters\n" string. Is this a concern? >> > > That could be a good thing, no? you get to see the action name with the > error. Its really not a big deal if you decide to do a->terse_print() > instead. Maybe. Just saying that this change would also change user-visible iproute2 behavior. > >>> >>> BTW: the action index, unless i missed something, is not transported >>> from the kernel for terse option. It is an important parameter >>> when actions are shared by filters (since they will have the same >>> index). >>> Am i missing something? >> >> Yes, tc_action_ops->dump(), which outputs action index among other data, >> is not called at all by terse dump. > > I am suggesting it is an important detail that is currently missing. > Alternatively since you have the cookies in there - it is feasible that > someone who creates the action could "encode" the index in the cookie. > But that makes it a "proprietary" choice of whoever is creating > the filter/action. It is not a trivial change. To get this data we need to call tc_action_ops->dump() which puts bunch of other unrelated info in TCA_OPTIONS nested attr. This hurts both dump size and runtime performance. Even if we add another argument to dump "terse dump, print only index", index is still part of larger options structure which includes at least following fields: #define tc_gen \ __u32 index; \ __u32 capab; \ int action; \ int refcnt; \ int bindcnt This wouldn't be much of a terse dump anymore. What prevents user that needs all action info from calling regular dump? It is not like terse dump substitutes it or somehow makes it harder to use. > > cheers, > jamal
On 2020-10-19 11:18 a.m., Vlad Buslov wrote: > > On Mon 19 Oct 2020 at 16:48, Jamal Hadi Salim <jhs@mojatatu.com> wrote: >> On 2020-10-18 8:16 a.m., Vlad Buslov wrote: [..] >> That could be a good thing, no? you get to see the action name with the >> error. Its really not a big deal if you decide to do a->terse_print() >> instead. > > Maybe. Just saying that this change would also change user-visible > iproute2 behavior. > You are right(for the non-terse output). tbh, not sure if it is a big deal given it happens only for the error case (where scripts look for exit codes typically); having said that: a ->terse_print() would be ok > It is not a trivial change. To get this data we need to call > tc_action_ops->dump() which puts bunch of other unrelated info in > TCA_OPTIONS nested attr. This hurts both dump size and runtime > performance. Even if we add another argument to dump "terse dump, print > only index", index is still part of larger options structure which > includes at least following fields: > > #define tc_gen \ > __u32 index; \ > __u32 capab; \ > int action; \ > int refcnt; \ > int bindcnt > index is the _only_ important field for analytics purposes in that list. i.e if i know the index i can correlate stats with one or more filters (whether shared or not). My worry is you have a very specific use case for your hardware or maybe it is ovs - where counters are uniquely tied to filters and there is no sharing. And possibly maybe only one counter can be tied to a filter (was not sure if you could handle more than one action in the terse from looking at the code). Our assumptions so far had no such constraints. Maybe a new TERSE_OPTIONS TLV, and then add an extra flag to indicate interest in the tlv? Peharps store the stats in it as well. > This wouldn't be much of a terse dump anymore. What prevents user that > needs all action info from calling regular dump? It is not like terse > dump substitutes it or somehow makes it harder to use. Both scaling and correctness are important. You have the cookie in the terse dump, thats a lot of data. In our case we totally bypass filters to reduce the amount of data crossing to user space (tc action ls). Theres still a lot of data crossing which we could trim with a terse dump. All we are interested in are stats. Another alternative is perhaps to introduce the index for the direct dump. cheers, jamal
On Tue 20 Oct 2020 at 15:29, Jamal Hadi Salim <jhs@mojatatu.com> wrote: > On 2020-10-19 11:18 a.m., Vlad Buslov wrote: >> >> On Mon 19 Oct 2020 at 16:48, Jamal Hadi Salim <jhs@mojatatu.com> wrote: >>> On 2020-10-18 8:16 a.m., Vlad Buslov wrote: > > [..] > >>> That could be a good thing, no? you get to see the action name with the >>> error. Its really not a big deal if you decide to do a->terse_print() >>> instead. >> >> Maybe. Just saying that this change would also change user-visible >> iproute2 behavior. >> > > You are right(for the non-terse output). tbh, not sure if it is a big > deal given it happens only for the error case (where scripts look > for exit codes typically); having said that: > a ->terse_print() would be ok > >> It is not a trivial change. To get this data we need to call >> tc_action_ops->dump() which puts bunch of other unrelated info in >> TCA_OPTIONS nested attr. This hurts both dump size and runtime >> performance. Even if we add another argument to dump "terse dump, print >> only index", index is still part of larger options structure which >> includes at least following fields: >> >> #define tc_gen \ >> __u32 index; \ >> __u32 capab; \ >> int action; \ >> int refcnt; \ >> int bindcnt >> > > > index is the _only_ important field for analytics purposes in that list. > i.e if i know the index i can correlate stats with one or more > filters (whether shared or not). > My worry is you have a very specific use case for your hardware or > maybe it is ovs - where counters are uniquely tied to filters and > there is no sharing. And possibly maybe only one counter can be tied > to a filter (was not sure if you could handle more than one action > in the terse from looking at the code). OVS uses cookie to uniquely identify the flow and it does support multiple actions per flow. > Our assumptions so far had no such constraints. > Maybe a new TERSE_OPTIONS TLV, and then add an extra flag > to indicate interest in the tlv? Peharps store the stats in it as well. Maybe, but wouldn't that require making it a new dump mode? Current terse dump is already in released kernel and this seems like a backward-incompatible change. > >> This wouldn't be much of a terse dump anymore. What prevents user that >> needs all action info from calling regular dump? It is not like terse >> dump substitutes it or somehow makes it harder to use. > > Both scaling and correctness are important. You have the cookie > in the terse dump, thats a lot of data. Cookie only consumes space in resulting netlink packet if used set the cookie during action init. Otherwise, the cookie attribute is omitted. > In our case we totally bypass filters to reduce the amount of data > crossing to user space (tc action ls). Theres still a lot of data > crossing which we could trim with a terse dump. All we are interested > in are stats. Another alternative is perhaps to introduce the index for > the direct dump. What is the direct dump? > > cheers, > jamal
On 2020-10-21 4:19 a.m., Vlad Buslov wrote: > > On Tue 20 Oct 2020 at 15:29, Jamal Hadi Salim <jhs@mojatatu.com> wrote: >> On 2020-10-19 11:18 a.m., Vlad Buslov wrote: >> My worry is you have a very specific use case for your hardware or >> maybe it is ovs - where counters are uniquely tied to filters and >> there is no sharing. And possibly maybe only one counter can be tied >> to a filter (was not sure if you could handle more than one action >> in the terse from looking at the code). > > OVS uses cookie to uniquely identify the flow and it does support > multiple actions per flow. ok, so they use it like a flowid/classid to identify the flow. In our use case the cookie stores all kinds of other state that the controller can avoid to lookup after a query. index otoh is universal i.e two different users can intepret it per action tying it specific stats. IOW: I dont think it replaces the index. Do they set cookies on all actions in a flow? >> Our assumptions so far had no such constraints. >> Maybe a new TERSE_OPTIONS TLV, and then add an extra flag >> to indicate interest in the tlv? Peharps store the stats in it as well. > > Maybe, but wouldn't that require making it a new dump mode? Current > terse dump is already in released kernel and this seems like a > backward-incompatible change. > I meant you would set a new flag(in addition to TERSE) in a request to the kernel to ask for the index to be made available on the response. Response comes back in a TLV with just index in it for now. >> >>> This wouldn't be much of a terse dump anymore. What prevents user that >>> needs all action info from calling regular dump? It is not like terse >>> dump substitutes it or somehow makes it harder to use. >> >> Both scaling and correctness are important. You have the cookie >> in the terse dump, thats a lot of data. > > Cookie only consumes space in resulting netlink packet if used set the > cookie during action init. Otherwise, the cookie attribute is omitted. True, but: I am wondering why it is even considered in when terseness was a requirement (and index was left out). >> In our case we totally bypass filters to reduce the amount of data >> crossing to user space (tc action ls). Theres still a lot of data >> crossing which we could trim with a terse dump. All we are interested >> in are stats. Another alternative is perhaps to introduce the index for >> the direct dump. > > What is the direct dump? tc action ls ... Like i said in our use cases to get the stats we just dumped the actions we wanted. It is a lot less data than having the filter + actions. And with your idea of terseness we can trim down further how much data by removing all the action attributes coming back if we set TERSE flag in such a request. But the index has to be there to make sense. cheers, jamal
On Thu 22 Oct 2020 at 17:05, Jamal Hadi Salim <jhs@mojatatu.com> wrote: > On 2020-10-21 4:19 a.m., Vlad Buslov wrote: >> >> On Tue 20 Oct 2020 at 15:29, Jamal Hadi Salim <jhs@mojatatu.com> wrote: >>> On 2020-10-19 11:18 a.m., Vlad Buslov wrote: >>> My worry is you have a very specific use case for your hardware or >>> maybe it is ovs - where counters are uniquely tied to filters and >>> there is no sharing. And possibly maybe only one counter can be tied >>> to a filter (was not sure if you could handle more than one action >>> in the terse from looking at the code). >> >> OVS uses cookie to uniquely identify the flow and it does support >> multiple actions per flow. > > > ok, so they use it like a flowid/classid to identify the flow. > In our use case the cookie stores all kinds of other state that > the controller can avoid to lookup after a query. > index otoh is universal i.e two different users can intepret it > per action tying it specific stats. > IOW: I dont think it replaces the index. > Do they set cookies on all actions in a flow? AFAIK on only one action per flow. > > >>> Our assumptions so far had no such constraints. >>> Maybe a new TERSE_OPTIONS TLV, and then add an extra flag >>> to indicate interest in the tlv? Peharps store the stats in it as well. >> >> Maybe, but wouldn't that require making it a new dump mode? Current >> terse dump is already in released kernel and this seems like a >> backward-incompatible change. >> > > I meant you would set a new flag(in addition to TERSE) in a request to > the kernel to ask for the index to be made available on the response. > Response comes back in a TLV with just index in it for now. Makes sense. > >>> >>>> This wouldn't be much of a terse dump anymore. What prevents user that >>>> needs all action info from calling regular dump? It is not like terse >>>> dump substitutes it or somehow makes it harder to use. >>> >>> Both scaling and correctness are important. You have the cookie >>> in the terse dump, thats a lot of data. >> >> Cookie only consumes space in resulting netlink packet if used set the >> cookie during action init. Otherwise, the cookie attribute is omitted. > > True, but: I am wondering why it is even considered in when terseness > was a requirement (and index was left out). There was several reasons for me to include it: - As I wrote in previous email its TLV is only included in dump if user set the cookie. Users who don't use cookies don't lose any performance of terse dump. - Including it didn't require any changes to tc_action_ops->dump() (like passing 'terse' flag or introducing dedicated terse_dump() callback) because it is processed in tcf_action_dump_1(). - OVS was the main use-case for us because it relies on filter dump for flow revalidation and uses cookie to identify the flows. > >>> In our case we totally bypass filters to reduce the amount of data >>> crossing to user space (tc action ls). Theres still a lot of data >>> crossing which we could trim with a terse dump. All we are interested >>> in are stats. Another alternative is perhaps to introduce the index for >>> the direct dump. >> >> What is the direct dump? > > tc action ls ... > Like i said in our use cases to get the stats we just dumped the actions > we wanted. It is a lot less data than having the filter + actions. > And with your idea of terseness we can trim down further how much > data by removing all the action attributes coming back if we set TERSE > flag in such a request. But the index has to be there to make sense. Yes, that makes sense. I guess introducing something like 'tc action -br ls ..' mode implemented by means of existing terse flag + new 'also output action index' flag would achieve that goal. > > cheers, > jamal
On 2020-10-23 8:48 a.m., Vlad Buslov wrote: > On Thu 22 Oct 2020 at 17:05, Jamal Hadi Salim <jhs@mojatatu.com> wrote: >> On 2020-10-21 4:19 a.m., Vlad Buslov wrote: >>> >>> On Tue 20 Oct 2020 at 15:29, Jamal Hadi Salim <jhs@mojatatu.com> wrote: >>>> On 2020-10-19 11:18 a.m., Vlad Buslov wrote: >>>> My worry is you have a very specific use case for your hardware or >>>> maybe it is ovs - where counters are uniquely tied to filters and >>>> there is no sharing. And possibly maybe only one counter can be tied >>>> to a filter (was not sure if you could handle more than one action >>>> in the terse from looking at the code). >>> >>> OVS uses cookie to uniquely identify the flow and it does support >>> multiple actions per flow. >> >> >> ok, so they use it like a flowid/classid to identify the flow. >> In our use case the cookie stores all kinds of other state that >> the controller can avoid to lookup after a query. >> index otoh is universal i.e two different users can intepret it >> per action tying it specific stats. >> IOW: I dont think it replaces the index. >> Do they set cookies on all actions in a flow? > > AFAIK on only one action per flow. > To each their own i guess. Sounds like it is being used as flowid entity. We pack a lot of metaencoding into those cookies. And to us a "service" is essentially a filter match folowed by a graph of actions (which could cyclic). >>> Cookie only consumes space in resulting netlink packet if used set the >>> cookie during action init. Otherwise, the cookie attribute is omitted. >> >> True, but: I am wondering why it is even considered in when terseness >> was a requirement (and index was left out). > > There was several reasons for me to include it: > > - As I wrote in previous email its TLV is only included in dump if user > set the cookie. Users who don't use cookies don't lose any performance > of terse dump. > > - Including it didn't require any changes to tc_action_ops->dump() (like > passing 'terse' flag or introducing dedicated terse_dump() callback) > because it is processed in tcf_action_dump_1(). > > - OVS was the main use-case for us because it relies on filter dump for > flow revalidation and uses cookie to identify the flows. > Which is fine - but it is a very ovs specific need. >> >>>> In our case we totally bypass filters to reduce the amount of data >>>> crossing to user space (tc action ls). Theres still a lot of data >>>> crossing which we could trim with a terse dump. All we are interested >>>> in are stats. Another alternative is perhaps to introduce the index for >>>> the direct dump. >>> >>> What is the direct dump? >> >> tc action ls ... >> Like i said in our use cases to get the stats we just dumped the actions >> we wanted. It is a lot less data than having the filter + actions. >> And with your idea of terseness we can trim down further how much >> data by removing all the action attributes coming back if we set TERSE >> flag in such a request. But the index has to be there to make sense. > > Yes, that makes sense. I guess introducing something like 'tc action -br > ls ..' mode implemented by means of existing terse flag + new 'also > output action index' flag would achieve that goal. > Right. There should be no interest in the cookie here at all. Maybe it could be optional with a flag indication. Have time to cook a patch? I'll taste/test it. cheers, jamal
On Sat 24 Oct 2020 at 20:40, Jamal Hadi Salim <jhs@mojatatu.com> wrote: > On 2020-10-23 8:48 a.m., Vlad Buslov wrote: >> On Thu 22 Oct 2020 at 17:05, Jamal Hadi Salim <jhs@mojatatu.com> wrote: >>> On 2020-10-21 4:19 a.m., Vlad Buslov wrote: >>>> >>>> On Tue 20 Oct 2020 at 15:29, Jamal Hadi Salim <jhs@mojatatu.com> wrote: >>>>> On 2020-10-19 11:18 a.m., Vlad Buslov wrote: >>>>> My worry is you have a very specific use case for your hardware or >>>>> maybe it is ovs - where counters are uniquely tied to filters and >>>>> there is no sharing. And possibly maybe only one counter can be tied >>>>> to a filter (was not sure if you could handle more than one action >>>>> in the terse from looking at the code). >>>> >>>> OVS uses cookie to uniquely identify the flow and it does support >>>> multiple actions per flow. >>> >>> >>> ok, so they use it like a flowid/classid to identify the flow. >>> In our use case the cookie stores all kinds of other state that >>> the controller can avoid to lookup after a query. >>> index otoh is universal i.e two different users can intepret it >>> per action tying it specific stats. >>> IOW: I dont think it replaces the index. >>> Do they set cookies on all actions in a flow? >> >> AFAIK on only one action per flow. >> > > To each their own i guess. Sounds like it is being used as flowid > entity. > We pack a lot of metaencoding into those cookies. And to us > a "service" is essentially a filter match folowed by a graph > of actions (which could cyclic). > > >>>> Cookie only consumes space in resulting netlink packet if used set the >>>> cookie during action init. Otherwise, the cookie attribute is omitted. >>> >>> True, but: I am wondering why it is even considered in when terseness >>> was a requirement (and index was left out). >> >> There was several reasons for me to include it: >> >> - As I wrote in previous email its TLV is only included in dump if user >> set the cookie. Users who don't use cookies don't lose any performance >> of terse dump. >> >> - Including it didn't require any changes to tc_action_ops->dump() (like >> passing 'terse' flag or introducing dedicated terse_dump() callback) >> because it is processed in tcf_action_dump_1(). >> >> - OVS was the main use-case for us because it relies on filter dump for >> flow revalidation and uses cookie to identify the flows. >> > > Which is fine - but it is a very ovs specific need. >>> >>>>> In our case we totally bypass filters to reduce the amount of data >>>>> crossing to user space (tc action ls). Theres still a lot of data >>>>> crossing which we could trim with a terse dump. All we are interested >>>>> in are stats. Another alternative is perhaps to introduce the index for >>>>> the direct dump. >>>> >>>> What is the direct dump? >>> >>> tc action ls ... >>> Like i said in our use cases to get the stats we just dumped the actions >>> we wanted. It is a lot less data than having the filter + actions. >>> And with your idea of terseness we can trim down further how much >>> data by removing all the action attributes coming back if we set TERSE >>> flag in such a request. But the index has to be there to make sense. >> >> Yes, that makes sense. I guess introducing something like 'tc action -br >> ls ..' mode implemented by means of existing terse flag + new 'also >> output action index' flag would achieve that goal. >> > > Right. There should be no interest in the cookie here at all. Maybe > it could be optional with a flag indication. > Have time to cook a patch? I'll taste/test it. Patch to make cookie in filter terse dump optional? That would break existing terse dump users that rely on it (OVS). > > cheers, > jamal
On 10/26/20 5:28 AM, Vlad Buslov wrote: > Patch to make cookie in filter terse dump optional? That would break > existing terse dump users that rely on it (OVS). Maybe I missed something in the discussions. terse dump for tc has not been committed to the tree yet, so there are no users relying on it.
On Mon 26 Oct 2020 at 16:52, David Ahern <dsahern@gmail.com> wrote: > On 10/26/20 5:28 AM, Vlad Buslov wrote: >> Patch to make cookie in filter terse dump optional? That would break >> existing terse dump users that rely on it (OVS). > > Maybe I missed something in the discussions. terse dump for tc has not > been committed to the tree yet, so there are no users relying on it. What do you mean? Kernel terse dump flag and implementation have been committed long time ago and are now present in released kernels.
On 10/26/20 9:06 AM, Vlad Buslov wrote: > What do you mean? Kernel terse dump flag and implementation have been > committed long time ago and are now present in released kernels. > ah, kernel side feature, not the iproute2 change.
On 2020-10-26 7:28 a.m., Vlad Buslov wrote: > > On Sat 24 Oct 2020 at 20:40, Jamal Hadi Salim <jhs@mojatatu.com> wrote: [..] >>> >>> Yes, that makes sense. I guess introducing something like 'tc action -br >>> ls ..' mode implemented by means of existing terse flag + new 'also >>> output action index' flag would achieve that goal. >>> >> >> Right. There should be no interest in the cookie here at all. Maybe >> it could be optional with a flag indication. >> Have time to cook a patch? I'll taste/test it. > > Patch to make cookie in filter terse dump optional? That would break > existing terse dump users that rely on it (OVS). Meant patch for 'tc action -br ls' Which by default would not include the cookie. cheers, jamal
On Mon 26 Oct 2020 at 19:12, Jamal Hadi Salim <jhs@mojatatu.com> wrote: > On 2020-10-26 7:28 a.m., Vlad Buslov wrote: >> >> On Sat 24 Oct 2020 at 20:40, Jamal Hadi Salim <jhs@mojatatu.com> wrote: > > [..] >>>> >>>> Yes, that makes sense. I guess introducing something like 'tc action -br >>>> ls ..' mode implemented by means of existing terse flag + new 'also >>>> output action index' flag would achieve that goal. >>>> >>> >>> Right. There should be no interest in the cookie here at all. Maybe >>> it could be optional with a flag indication. >>> Have time to cook a patch? I'll taste/test it. >> >> Patch to make cookie in filter terse dump optional? That would break >> existing terse dump users that rely on it (OVS). > > Meant patch for 'tc action -br ls' > > Which by default would not include the cookie. So action-dump-specific flag that causes act api to output action index (via new attribute) and skips cookie? > > cheers, > jamal
On 2020-10-26 1:46 p.m., Vlad Buslov wrote: > > On Mon 26 Oct 2020 at 19:12, Jamal Hadi Salim <jhs@mojatatu.com> wrote: >> On 2020-10-26 7:28 a.m., Vlad Buslov wrote: >>> >>> On Sat 24 Oct 2020 at 20:40, Jamal Hadi Salim <jhs@mojatatu.com> wrote: >> >> [..] >>>>> >>>>> Yes, that makes sense. I guess introducing something like 'tc action -br >>>>> ls ..' mode implemented by means of existing terse flag + new 'also >>>>> output action index' flag would achieve that goal. >>>>> >>>> >>>> Right. There should be no interest in the cookie here at all. Maybe >>>> it could be optional with a flag indication. >>>> Have time to cook a patch? I'll taste/test it. >>> >>> Patch to make cookie in filter terse dump optional? That would break >>> existing terse dump users that rely on it (OVS). >> >> Meant patch for 'tc action -br ls' >> >> Which by default would not include the cookie. > > So action-dump-specific flag that causes act api to output action index > (via new attribute) and skips cookie? > yeah, something like TCA_ACT_FLAGS_TERSE. new tcf_action_dump_terse() takes one more field which says to include or not the cookies since that is shared code and filters can always include it. The action index is already present in the passed tc_action struct just needs a new TLV. cheers, jamal
On Mon 26 Oct 2020 at 20:01, Jamal Hadi Salim <jhs@mojatatu.com> wrote: > On 2020-10-26 1:46 p.m., Vlad Buslov wrote: >> >> On Mon 26 Oct 2020 at 19:12, Jamal Hadi Salim <jhs@mojatatu.com> wrote: >>> On 2020-10-26 7:28 a.m., Vlad Buslov wrote: >>>> >>>> On Sat 24 Oct 2020 at 20:40, Jamal Hadi Salim <jhs@mojatatu.com> wrote: >>> >>> [..] >>>>>> >>>>>> Yes, that makes sense. I guess introducing something like 'tc action -br >>>>>> ls ..' mode implemented by means of existing terse flag + new 'also >>>>>> output action index' flag would achieve that goal. >>>>>> >>>>> >>>>> Right. There should be no interest in the cookie here at all. Maybe >>>>> it could be optional with a flag indication. >>>>> Have time to cook a patch? I'll taste/test it. >>>> >>>> Patch to make cookie in filter terse dump optional? That would break >>>> existing terse dump users that rely on it (OVS). >>> >>> Meant patch for 'tc action -br ls' >>> >>> Which by default would not include the cookie. >> >> So action-dump-specific flag that causes act api to output action index >> (via new attribute) and skips cookie? >> > > yeah, something like TCA_ACT_FLAGS_TERSE. > > new tcf_action_dump_terse() takes one more field which says to > include or not the cookies since that is shared code and filters > can always include it. > The action index is already present in the passed tc_action > struct just needs a new TLV. Sure, I'll try to find time this week.
On 2020-10-26 2:03 p.m., Vlad Buslov wrote: > > On Mon 26 Oct 2020 at 20:01, Jamal Hadi Salim <jhs@mojatatu.com> wrote: >> On 2020-10-26 1:46 p.m., Vlad Buslov wrote: >>> >> yeah, something like TCA_ACT_FLAGS_TERSE. >> >> new tcf_action_dump_terse() takes one more field which says to >> include or not the cookies since that is shared code and filters >> can always include it. >> The action index is already present in the passed tc_action >> struct just needs a new TLV. > > Sure, I'll try to find time this week. Thank you! cheers, jamal
diff --git a/man/man8/tc.8 b/man/man8/tc.8 index 7e9019f561ea..e8622053df65 100644 --- a/man/man8/tc.8 +++ b/man/man8/tc.8 @@ -854,6 +854,12 @@ option for creating alias. .RE +.TP +.BR "\-br" , " \-brief" +Print only essential data needed to identify the filter and action (handle, +cookie, etc.) and stats. This option is currently only supported by +.BR "tc filter show " command. + .SH "EXAMPLES" .PP tc -g class show dev eth0 diff --git a/tc/tc.c b/tc/tc.c index 5d57054b45fb..bdd5d4faf886 100644 --- a/tc/tc.c +++ b/tc/tc.c @@ -44,6 +44,7 @@ bool use_names; int json; int color; int oneline; +int brief; static char *conf_file; @@ -202,7 +203,8 @@ static void usage(void) " OPTIONS := { -V[ersion] | -s[tatistics] | -d[etails] | -r[aw] |\n" " -o[neline] | -j[son] | -p[retty] | -c[olor]\n" " -b[atch] [filename] | -n[etns] name | -N[umeric] |\n" - " -nm | -nam[es] | { -cf | -conf } path }\n"); + " -nm | -nam[es] | { -cf | -conf } path\n" + " -br[ief] }\n"); } static int do_cmd(int argc, char **argv) @@ -336,6 +338,8 @@ int main(int argc, char **argv) ++json; } else if (matches(argv[1], "-oneline") == 0) { ++oneline; + }else if (matches(argv[1], "-brief") == 0) { + ++brief; } else { fprintf(stderr, "Option \"%s\" is unknown, try \"tc -help\".\n", diff --git a/tc/tc_filter.c b/tc/tc_filter.c index c591a19f3123..71be2e8119c9 100644 --- a/tc/tc_filter.c +++ b/tc/tc_filter.c @@ -721,6 +721,15 @@ static int tc_filter_list(int cmd, int argc, char **argv) if (filter_chain_index_set) addattr32(&req.n, sizeof(req), TCA_CHAIN, chain_index); + if (brief) { + struct nla_bitfield32 flags = { + .value = TCA_DUMP_FLAGS_TERSE, + .selector = TCA_DUMP_FLAGS_TERSE + }; + + addattr_l(&req.n, MAX_MSG, TCA_DUMP_FLAGS, &flags, sizeof(flags)); + } + if (rtnl_dump_request_n(&rth, &req.n) < 0) { perror("Cannot send dump request"); return 1;