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2019-06-19treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500Thomas Gleixner1-4/+1
Based on 2 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation # extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 4122 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Enrico Weigelt <info@metux.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-28netlink: make validation more configurable for future strictnessJohannes Berg1-2/+2
We currently have two levels of strict validation: 1) liberal (default) - undefined (type >= max) & NLA_UNSPEC attributes accepted - attribute length >= expected accepted - garbage at end of message accepted 2) strict (opt-in) - NLA_UNSPEC attributes accepted - attribute length >= expected accepted Split out parsing strictness into four different options: * TRAILING - check that there's no trailing data after parsing attributes (in message or nested) * MAXTYPE - reject attrs > max known type * UNSPEC - reject attributes with NLA_UNSPEC policy entries * STRICT_ATTRS - strictly validate attribute size The default for future things should be *everything*. The current *_strict() is a combination of TRAILING and MAXTYPE, and is renamed to _deprecated_strict(). The current regular parsing has none of this, and is renamed to *_parse_deprecated(). Additionally it allows us to selectively set one of the new flags even on old policies. Notably, the UNSPEC flag could be useful in this case, since it can be arranged (by filling in the policy) to not be an incompatible userspace ABI change, but would then going forward prevent forgetting attribute entries. Similar can apply to the POLICY flag. We end up with the following renames: * nla_parse -> nla_parse_deprecated * nla_parse_strict -> nla_parse_deprecated_strict * nlmsg_parse -> nlmsg_parse_deprecated * nlmsg_parse_strict -> nlmsg_parse_deprecated_strict * nla_parse_nested -> nla_parse_nested_deprecated * nla_validate_nested -> nla_validate_nested_deprecated Using spatch, of course: @@ expression TB, MAX, HEAD, LEN, POL, EXT; @@ -nla_parse(TB, MAX, HEAD, LEN, POL, EXT) +nla_parse_deprecated(TB, MAX, HEAD, LEN, POL, EXT) @@ expression NLH, HDRLEN, TB, MAX, POL, EXT; @@ -nlmsg_parse(NLH, HDRLEN, TB, MAX, POL, EXT) +nlmsg_parse_deprecated(NLH, HDRLEN, TB, MAX, POL, EXT) @@ expression NLH, HDRLEN, TB, MAX, POL, EXT; @@ -nlmsg_parse_strict(NLH, HDRLEN, TB, MAX, POL, EXT) +nlmsg_parse_deprecated_strict(NLH, HDRLEN, TB, MAX, POL, EXT) @@ expression TB, MAX, NLA, POL, EXT; @@ -nla_parse_nested(TB, MAX, NLA, POL, EXT) +nla_parse_nested_deprecated(TB, MAX, NLA, POL, EXT) @@ expression START, MAX, POL, EXT; @@ -nla_validate_nested(START, MAX, POL, EXT) +nla_validate_nested_deprecated(START, MAX, POL, EXT) @@ expression NLH, HDRLEN, MAX, POL, EXT; @@ -nlmsg_validate(NLH, HDRLEN, MAX, POL, EXT) +nlmsg_validate_deprecated(NLH, HDRLEN, MAX, POL, EXT) For this patch, don't actually add the strict, non-renamed versions yet so that it breaks compile if I get it wrong. Also, while at it, make nla_validate and nla_parse go down to a common __nla_validate_parse() function to avoid code duplication. Ultimately, this allows us to have very strict validation for every new caller of nla_parse()/nlmsg_parse() etc as re-introduced in the next patch, while existing things will continue to work as is. In effect then, this adds fully strict validation for any new command. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-28netlink: make nla_nest_start() add NLA_F_NESTED flagMichal Kubecek1-1/+1
Even if the NLA_F_NESTED flag was introduced more than 11 years ago, most netlink based interfaces (including recently added ones) are still not setting it in kernel generated messages. Without the flag, message parsers not aware of attribute semantics (e.g. wireshark dissector or libmnl's mnl_nlmsg_fprintf()) cannot recognize nested attributes and won't display the structure of their contents. Unfortunately we cannot just add the flag everywhere as there may be userspace applications which check nlattr::nla_type directly rather than through a helper masking out the flags. Therefore the patch renames nla_nest_start() to nla_nest_start_noflag() and introduces nla_nest_start() as a wrapper adding NLA_F_NESTED. The calls which add NLA_F_NESTED manually are rewritten to use nla_nest_start(). Except for changes in include/net/netlink.h, the patch was generated using this semantic patch: @@ expression E1, E2; @@ -nla_nest_start(E1, E2) +nla_nest_start_noflag(E1, E2) @@ expression E1, E2; @@ -nla_nest_start_noflag(E1, E2 | NLA_F_NESTED) +nla_nest_start(E1, E2) Signed-off-by: Michal Kubecek <mkubecek@suse.cz> Acked-by: Jiri Pirko <jiri@mellanox.com> Acked-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-02net: sched: introduce and use qdisc tree flush/purge helpersPaolo Abeni1-10/+1
The same code to flush qdisc tree and purge the qdisc queue is duplicated in many places and in most cases it does not respect NOLOCK qdisc: the global backlog len is used and the per CPU values are ignored. This change addresses the above, factoring-out the relevant code and using the helpers introduced by the previous patch to fetch the correct backlog len. Fixes: c5ad119fb6c0 ("net: sched: pfifo_fast use skb_array") Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-02net: sched: introduce and use qstats read helpersPaolo Abeni1-2/+1
Classful qdiscs can't access directly the child qdiscs backlog length: if such qdisc is NOLOCK, per CPU values should be accounted instead. Most qdiscs no not respect the above. As a result, qstats fetching for most classful qdisc is currently incorrect: if the child qdisc is NOLOCK, it always reports 0 len backlog. This change introduces a pair of helpers to safely fetch both backlog and qlen and use them in stats class dumping functions, fixing the above issue and cleaning a bit the code. DRR needs also to access the child qdisc queue length, so it needs custom handling. Fixes: c5ad119fb6c0 ("net: sched: pfifo_fast use skb_array") Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-16sched: Fix detection of empty queues in child qdiscsToke Høiland-Jørgensen1-1/+3
Several qdiscs check on enqueue whether the packet was enqueued to a class with an empty queue, in which case the class is activated. This is done by checking if the qlen is exactly 1 after enqueue. However, if GSO splitting is enabled in the child qdisc, a single packet can result in a qlen longer than 1. This means the activation check fails, leading to a stalled queue. Fix this by checking if the queue is empty *before* enqueue, and running the activation logic if this was the case. Reported-by: Pete Heist <pete@heistp.net> Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-16sched: Avoid dereferencing skb pointer after child enqueueToke Høiland-Jørgensen1-7/+9
Parent qdiscs may dereference the pointer to the enqueued skb after enqueue. However, both CAKE and TBF call consume_skb() on the original skb when splitting GSO packets, leading to a potential use-after-free in the parent. Fix this by avoiding dereferencing the skb pointer after enqueueing to the child. Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-26net: sched: rename qdisc_destroy() to qdisc_put()Vlad Buslov1-2/+2
Current implementation of qdisc_destroy() decrements Qdisc reference counter and only actually destroy Qdisc if reference counter value reached zero. Rename qdisc_destroy() to qdisc_put() in order for it to better describe the way in which this function currently implemented and used. Extract code that deallocates Qdisc into new private qdisc_destroy() function. It is intended to be shared between regular qdisc_put() and its unlocked version that is introduced in next patch in this series. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-21net: sch: api: add extack support in qdisc_create_dfltAlexander Aring1-4/+4
This patch adds extack support for the function qdisc_create_dflt which is a common used function in the tc subsystem. Callers which are interested in the receiving error can assign extack to get a more detailed information why qdisc_create_dflt failed. The function qdisc_create_dflt will also call an init callback which can fail by any per-qdisc specific handling. Cc: David Ahern <dsahern@gmail.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Alexander Aring <aring@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-21net: sch: api: add extack support in tcf_block_getAlexander Aring1-1/+1
This patch adds extack support for the function tcf_block_get which is a common used function in the tc subsystem. Callers which are interested in the receiving error can assign extack to get a more detailed information why tcf_block_get failed. Cc: David Ahern <dsahern@gmail.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Alexander Aring <aring@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-21net: sched: sch: add extack for graft callbackAlexander Aring1-1/+2
This patch adds extack support for graft callback to prepare per-qdisc specific changes for extack. Cc: David Ahern <dsahern@gmail.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Alexander Aring <aring@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-21net: sched: sch: add extack for block callbackAlexander Aring1-1/+2
This patch adds extack support for block callback to prepare per-qdisc specific changes for extack. Cc: David Ahern <dsahern@gmail.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Alexander Aring <aring@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-21net: sched: sch: add extack to change classAlexander Aring1-1/+2
This patch adds extack support for class change callback api. This prepares to handle extack support inside each specific class implementation. Cc: David Ahern <dsahern@gmail.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Alexander Aring <aring@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-21net: sched: sch: add extack for init callbackAlexander Aring1-1/+2
This patch adds extack support for init callback to prepare per-qdisc specific changes for extack. Cc: David Ahern <dsahern@gmail.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Alexander Aring <aring@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-22net: sched: mark expected switch fall-throughsGustavo A. R. Silva1-0/+1
In preparation to enabling -Wimplicit-fallthrough, mark switch cases where we are expecting to fall through. Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-16net: sched: store Qdisc pointer in struct blockJiri Pirko1-1/+1
Prepare for removal of tp->q and store Qdisc pointer in the block structure. Signed-off-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-07sched: Use __qdisc_drop instead of kfree_skb in sch_prio and sch_qfqGao Feng1-1/+1
The commit 520ac30f4551 ("net_sched: drop packets after root qdisc lock is released) made a big change of tc for performance. There are two points left in sch_prio and sch_qfq which are not changed with that commit. Now enhance them now with __qdisc_drop. Signed-off-by: Gao Feng <gfree.wind@vip.163.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-26net_sched: remove tc class reference countingWANG Cong1-25/+5
For TC classes, their ->get() and ->put() are always paired, and the reference counting is completely useless, because: 1) For class modification and dumping paths, we already hold RTNL lock, so all of these ->get(),->change(),->put() are atomic. 2) For filter bindiing/unbinding, we use other reference counter than this one, and they should have RTNL lock too. 3) For ->qlen_notify(), it is special because it is called on ->enqueue() path, but we already hold qdisc tree lock there, and we hold this tree lock when graft or delete the class too, so it should not be gone or changed until we release the tree lock. Therefore, this patch removes ->get() and ->put(), but: 1) Adds a new ->find() to find the pointer to a class by classid, no refcnt. 2) Move the original class destroy upon the last refcnt into ->delete(), right after releasing tree lock. This is fine because the class is already removed from hash when holding the lock. For those who also use ->put() as ->unbind(), just rename them to reflect this change. Cc: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-16net_sched: call qlen_notify only if child qdisc is emptyKonstantin Khlebnikov1-2/+1
This callback is used for deactivating class in parent qdisc. This is cheaper to test queue length right here. Also this allows to catch draining screwed backlog and prevent second deactivation of already inactive parent class which will crash kernel for sure. Kernel with print warning at destruction of child qdisc where no packets but backlog is not zero. Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-06net: sched: introduce a TRAP control actionJiri Pirko1-0/+1
There is need to instruct the HW offloaded path to push certain matched packets to cpu/kernel for further analysis. So this patch introduces a new TRAP control action to TC. For kernel datapath, this action does not make much sense. So with the same logic as in HW, new TRAP behaves similar to STOLEN. The skb is just dropped in the datapath (and virtually ejected to an upper level, which does not exist in case of kernel). Signed-off-by: Jiri Pirko <jiri@mellanox.com> Reviewed-by: Yotam Gigi <yotamg@mellanox.com> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-17net: sched: introduce tcf block infractructureJiri Pirko1-5/+9
Currently, the filter chains are direcly put into the private structures of qdiscs. In order to be able to have multiple chains per qdisc and to allow filter chains sharing among qdiscs, there is a need for common object that would hold the chains. This introduces such object and calls it "tcf_block". Helpers to get and put the blocks are provided to be called from individual qdisc code. Also, the original filter_list pointers are left in qdisc privs to allow the entry into tcf_block processing without any added overhead of possible multiple pointer dereference on fast path. Signed-off-by: Jiri Pirko <jiri@mellanox.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-17net: sched: move tc_classify function to cls_api.cJiri Pirko1-1/+1
Move tc_classify function to cls_api.c where it belongs, rename it to fit the namespace. Signed-off-by: Jiri Pirko <jiri@mellanox.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-13netlink: pass extended ACK struct to parsing functionsJohannes Berg1-1/+2
Pass the new extended ACK reporting struct to all of the generic netlink parsing functions. For now, pass NULL in almost all callers (except for some in the core.) Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-13net: sched: make default fifo qdiscs appear in the dumpJiri Kosina1-0/+2
The original reason [1] for having hidden qdiscs (potential scalability issues in qdisc_match_from_root() with single linked list in case of large amount of qdiscs) has been invalidated by 59cc1f61f0 ("net: sched: convert qdisc linked list to hashtable"). This allows us for bringing more clarity and determinism into the dump by making default pfifo qdiscs visible. We're not turning this on by default though, at it was deemed [2] too intrusive / unnecessary change of default behavior towards userspace. Instead, TCA_DUMP_INVISIBLE netlink attribute is introduced, which allows applications to request complete qdisc hierarchy dump, including the ones that have always been implicit/invisible. Singleton noop_qdisc stays invisible, as teaching the whole infrastructure about singletons would require quite some surgery with very little gain (seeing no qdisc or seeing noop qdisc in the dump is probably setting the same user expectation). [1] http://lkml.kernel.org/r/1460732328.10638.74.camel@edumazet-glaptop3.roam.corp.google.com [2] http://lkml.kernel.org/r/20161021.105935.1907696543877061916.davem@davemloft.net Signed-off-by: Jiri Kosina <jkosina@suse.cz> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-05net_sched: gen_estimator: complete rewrite of rate estimatorsEric Dumazet1-4/+4
1) Old code was hard to maintain, due to complex lock chains. (We probably will be able to remove some kfree_rcu() in callers) 2) Using a single timer to update all estimators does not scale. 3) Code was buggy on 32bit kernel (WRITE_ONCE() on 64bit quantity is not supposed to work well) In this rewrite : - I removed the RB tree that had to be scanned in gen_estimator_active(). qdisc dumps should be much faster. - Each estimator has its own timer. - Estimations are maintained in net_rate_estimator structure, instead of dirtying the qdisc. Minor, but part of the simplification. - Reading the estimator uses RCU and a seqcount to provide proper support for 32bit kernels. - We reduce memory need when estimators are not used, since we store a pointer, instead of the bytes/packets counters. - xt_rateest_mt() no longer has to grab a spinlock. (In the future, xt_rateest_tg() could be switched to per cpu counters) Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-23sch_qfq: keep backlog updated with qlenWANG Cong1-0/+3
Reported-by: Stas Nichiporovich <stasn77@gmail.com> Fixes: 2ccccf5fb43f ("net_sched: update hierarchical backlog too") Cc: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-25net_sched: drop packets after root qdisc lock is releasedEric Dumazet1-3/+4
Qdisc performance suffers when packets are dropped at enqueue() time because drops (kfree_skb()) are done while qdisc lock is held, delaying a dequeue() draining the queue. Nominal throughput can be reduced by 50 % when this happens, at a time we would like the dequeue() to proceed as fast as possible. Even FQ is vulnerable to this problem, while one of FQ goals was to provide some flow isolation. This patch adds a 'struct sk_buff **to_free' parameter to all qdisc->enqueue(), and in qdisc_drop() helper. I measured a performance increase of up to 12 %, but this patch is a prereq so that future batches in enqueue() can fly. Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-10Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-2/+4
Conflicts: net/sched/act_police.c net/sched/sch_drr.c net/sched/sch_hfsc.c net/sched/sch_prio.c net/sched/sch_red.c net/sched/sch_tbf.c In net-next the drop methods of the packet schedulers got removed, so the bug fixes to them in 'net' are irrelevant. A packet action unload crash fix conflicts with the addition of the new firstuse timestamp. Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-09sched: remove qdisc->dropFlorian Westphal1-47/+0
after removal of TCA_CBQ_OVL_STRATEGY from cbq scheduler, there are no more callers of ->drop() outside of other ->drop functions, i.e. nothing calls them. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-09qfq: don't leak skb if kzalloc failsFlorian Westphal1-2/+4
When we need to create a new aggregate to enqueue the skb we call kzalloc. If that fails we returned ENOBUFS without freeing the skb. Spotted during code review. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-08net: sched: do not acquire qdisc spinlock in qdisc/class stats dumpEric Dumazet1-3/+6
Large tc dumps (tc -s {qdisc|class} sh dev ethX) done by Google BwE host agent [1] are problematic at scale : For each qdisc/class found in the dump, we currently lock the root qdisc spinlock in order to get stats. Sampling stats every 5 seconds from thousands of HTB classes is a challenge when the root qdisc spinlock is under high pressure. Not only the dumps take time, they also slow down the fast path (queue/dequeue packets) by 10 % to 20 % in some cases. An audit of existing qdiscs showed that sch_fq_codel is the only qdisc that might need the qdisc lock in fq_codel_dump_stats() and fq_codel_dump_class_stats() In v2 of this patch, I now use the Qdisc running seqcount to provide consistent reads of packets/bytes counters, regardless of 32/64 bit arches. I also changed rate estimators to use the same infrastructure so that they no longer need to lock root qdisc lock. [1] http://static.googleusercontent.com/media/research.google.com/en//pubs/archive/43838.pdf Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Cong Wang <xiyou.wangcong@gmail.com> Cc: Jamal Hadi Salim <jhs@mojatatu.com> Cc: John Fastabend <john.fastabend@gmail.com> Cc: Kevin Athey <kda@google.com> Cc: Xiaotian Pei <xiaotian@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-03-01net_sched: update hierarchical backlog tooWANG Cong1-1/+2
When the bottom qdisc decides to, for example, drop some packet, it calls qdisc_tree_decrease_qlen() to update the queue length for all its ancestors, we need to update the backlog too to keep the stats on root qdisc accurate. Cc: Jamal Hadi Salim <jhs@mojatatu.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-03-01net_sched: introduce qdisc_replace() helperWANG Cong1-5/+1
Remove nearly duplicated code and prepare for the following patch. Cc: Jamal Hadi Salim <jhs@mojatatu.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-28net: sched: consolidate tc_classify{,_compat}Daniel Borkmann1-1/+1
For classifiers getting invoked via tc_classify(), we always need an extra function call into tc_classify_compat(), as both are being exported as symbols and tc_classify() itself doesn't do much except handling of reclassifications when tp->classify() returned with TC_ACT_RECLASSIFY. CBQ and ATM are the only qdiscs that directly call into tc_classify_compat(), all others use tc_classify(). When tc actions are being configured out in the kernel, tc_classify() effectively does nothing besides delegating. We could spare this layer and consolidate both functions. pktgen on single CPU constantly pushing skbs directly into the netif_receive_skb() path with a dummy classifier on ingress qdisc attached, improves slightly from 22.3Mpps to 23.1Mpps. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-16pkt_sched: sch_qfq: remove unused member of struct qfq_schedAndrea Parri1-1/+0
The member (u32) "num_active_agg" of struct qfq_sched has been unused since its introduction in 462dbc9101acd38e92eda93c0726857517a24bbd "pkt_sched: QFQ Plus: fair-queueing service at DRR cost" and (AFAICT) there is no active plan to use it; this removes the member. Signed-off-by: Andrea Parri <parri.andrea@gmail.com> Acked-by: Paolo Valente <paolo.valente@unimore.it> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-21pkt_sched: sch_qfq: remove redundant -if- control statementAndrea Parri1-2/+1
The control !hlist_unhashed() in qfq_destroy_agg() is unnecessary because already performed in hlist_del_init(), so remove it. Signed-off-by: Andrea Parri <parri.andrea@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-30net: sched: enable per cpu qstatsJohn Fastabend1-1/+2
After previous patches to simplify qstats the qstats can be made per cpu with a packed union in Qdisc struct. Signed-off-by: John Fastabend <john.r.fastabend@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-30net: sched: restrict use of qstats qlenJohn Fastabend1-2/+1
This removes the use of qstats->qlen variable from the classifiers and makes it an explicit argument to gnet_stats_copy_queue(). The qlen represents the qdisc queue length and is packed into the qstats at the last moment before passnig to user space. By handling it explicitely we avoid, in the percpu stats case, having to figure out which per_cpu variable to put it in. It would probably be best to remove it from qstats completely but qstats is a user space ABI and can't be broken. A future patch could make an internal only qstats structure that would avoid having to allocate an additional u32 variable on the Qdisc struct. This would make the qstats struct 128bits instead of 128+32. Signed-off-by: John Fastabend <john.r.fastabend@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-30net: sched: implement qstat helper routinesJohn Fastabend1-2/+2
This adds helpers to manipulate qstats logic and replaces locations that touch the counters directly. This simplifies future patches to push qstats onto per cpu counters. Signed-off-by: John Fastabend <john.r.fastabend@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-30net: sched: make bstats per cpu and estimator RCU safeJohn Fastabend1-3/+5
In order to run qdisc's without locking statistics and estimators need to be handled correctly. To resolve bstats make the statistics per cpu. And because this is only needed for qdiscs that are running without locks which is not the case for most qdiscs in the near future only create percpu stats when qdiscs set the TCQ_F_CPUSTATS flag. Next because estimators use the bstats to calculate packets per second and bytes per second the estimator code paths are updated to use the per cpu statistics. Signed-off-by: John Fastabend <john.r.fastabend@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-13net: rcu-ify tcf_protoJohn Fastabend1-3/+6
rcu'ify tcf_proto this allows calling tc_classify() without holding any locks. Updaters are protected by RTNL. This patch prepares the core net_sched infrastracture for running the classifier/action chains without holding the qdisc lock however it does nothing to ensure cls_xxx and act_xxx types also work without locking. Additional patches are required to address the fall out. Signed-off-by: John Fastabend <john.r.fastabend@intel.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-07-19pkt_sched: sch_qfq: remove a source of high packet delay/jitterPaolo Valente1-29/+56
QFQ+ inherits from QFQ a design choice that may cause a high packet delay/jitter and a severe short-term unfairness. As QFQ, QFQ+ uses a special quantity, the system virtual time, to track the service provided by the ideal system it approximates. When a packet is dequeued, this quantity must be incremented by the size of the packet, divided by the sum of the weights of the aggregates waiting to be served. Tracking this sum correctly is a non-trivial task, because, to preserve tight service guarantees, the decrement of this sum must be delayed in a special way [1]: this sum can be decremented only after that its value would decrease also in the ideal system approximated by QFQ+. For efficiency, QFQ+ keeps track only of the 'instantaneous' weight sum, increased and decreased immediately as the weight of an aggregate changes, and as an aggregate is created or destroyed (which, in its turn, happens as a consequence of some class being created/destroyed/changed). However, to avoid the problems caused to service guarantees by these immediate decreases, QFQ+ increments the system virtual time using the maximum value allowed for the weight sum, 2^10, in place of the dynamic, instantaneous value. The instantaneous value of the weight sum is used only to check whether a request of weight increase or a class creation can be satisfied. Unfortunately, the problems caused by this choice are worse than the temporary degradation of the service guarantees that may occur, when a class is changed or destroyed, if the instantaneous value of the weight sum was used to update the system virtual time. In fact, the fraction of the link bandwidth guaranteed by QFQ+ to each aggregate is equal to the ratio between the weight of the aggregate and the sum of the weights of the competing aggregates. The packet delay guaranteed to the aggregate is instead inversely proportional to the guaranteed bandwidth. By using the maximum possible value, and not the actual value of the weight sum, QFQ+ provides each aggregate with the worst possible service guarantees, and not with service guarantees related to the actual set of competing aggregates. To see the consequences of this fact, consider the following simple example. Suppose that only the following aggregates are backlogged, i.e., that only the classes in the following aggregates have packets to transmit: one aggregate with weight 10, say A, and ten aggregates with weight 1, say B1, B2, ..., B10. In particular, suppose that these aggregates are always backlogged. Given the weight distribution, the smoothest and fairest service order would be: A B1 A B2 A B3 A B4 A B5 A B6 A B7 A B8 A B9 A B10 A B1 A B2 ... QFQ+ would provide exactly this optimal service if it used the actual value for the weight sum instead of the maximum possible value, i.e., 11 instead of 2^10. In contrast, since QFQ+ uses the latter value, it serves aggregates as follows (easy to prove and to reproduce experimentally): A B1 B2 B3 B4 B5 B6 B7 B8 B9 B10 A A A A A A A A A A B1 B2 ... B10 A A ... By replacing 10 with N in the above example, and by increasing N, one can increase at will the maximum packet delay and the jitter experienced by the classes in aggregate A. This patch addresses this issue by just using the above 'instantaneous' value of the weight sum, instead of the maximum possible value, when updating the system virtual time. After the instantaneous weight sum is decreased, QFQ+ may deviate from the ideal service for a time interval in the order of the time to serve one maximum-size packet for each backlogged class. The worst-case extent of the deviation exhibited by QFQ+ during this time interval [1] is basically the same as of the deviation described above (but, without this patch, QFQ+ suffers from such a deviation all the time). Finally, this patch modifies the comment to the function qfq_slot_insert, to make it coherent with the fact that the weight sum used by QFQ+ can now be lower than the maximum possible value. [1] P. Valente, "Extending WF2Q+ to support a dynamic traffic mix", Proceedings of AAA-IDEA'05, June 2005. Signed-off-by: Paolo Valente <paolo.valente@unimore.it> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-07-12pkt_sched: sch_qfq: remove forward declaration of qfq_update_agg_tsPaolo Valente1-63/+55
This patch removes the forward declaration of qfq_update_agg_ts, by moving the definition of the function above its first call. This patch also removes a useless forward declaration of qfq_schedule_agg. Reported-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paolo Valente <paolo.valente@unimore.it> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-07-12pkt_sched: sch_qfq: improve efficiency of make_eligiblePaolo Valente1-1/+8
In make_eligible, a mask is used to decide which groups must become eligible: the i-th group becomes eligible only if the i-th bit of the mask (from the right) is set. The mask is computed by left-shifting a 1 by a given number of places, and decrementing the result. The shift is performed on a ULL to avoid problems in case the number of places to shift is higher than 31. On a 32-bit machine, this is more costly than working on an UL. This patch replaces such a costly operation with two cheaper branches. The trick is based on the following fact: in case of a shift of at least 32 places, the resulting mask has at least the 32 less significant bits set, whereas the total number of groups is lower than 32. As a consequence, in this case it is enough to just set the 32 less significant bits of the mask with a cheaper ~0UL. In the other case, the shift can be safely performed on a UL. Reported-by: David S. Miller <davem@davemloft.net> Reported-by: David Laight <David.Laight@ACULAB.COM> Signed-off-by: Paolo Valente <paolo.valente@unimore.it> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-11net_sched: add 64bit rate estimatorsEric Dumazet1-1/+1
struct gnet_stats_rate_est contains u32 fields, so the bytes per second field can wrap at 34360Mbit. Add a new gnet_stats_rate_est64 structure to get 64bit bps/pps fields, and switch the kernel to use this structure natively. This structure is dumped to user space as a new attribute : TCA_STATS_RATE_EST64 Old tc command will now display the capped bps (to 34360Mbit), instead of wrapped values, and updated tc command will display correct information. Old tc command output, after patch : eric:~# tc -s -d qd sh dev lo qdisc pfifo 8001: root refcnt 2 limit 1000p Sent 80868245400 bytes 1978837 pkt (dropped 0, overlimits 0 requeues 0) rate 34360Mbit 189696pps backlog 0b 0p requeues 0 This patch carefully reorganizes "struct Qdisc" layout to get optimal performance on SMP. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-03-06pkt_sched: sch_qfq: remove a useless invocation of qfq_update_eligiblePaolo Valente1-2/+0
QFQ+ can select for service only 'eligible' aggregates, i.e., aggregates that would have started to be served also in the emulated ideal system. As a consequence, for QFQ+ to be work conserving, at least one of the active aggregates must be eligible when it is time to choose the next aggregate to serve. The set of eligible aggregates is updated through the function qfq_update_eligible(), which does guarantee that, after its invocation, at least one of the active aggregates is eligible. Because of this property, this function is invoked in qfq_deactivate_agg() to guarantee that at least one of the active aggregates is still eligible after an aggregate has been deactivated. In particular, the critical case is when there are other active aggregates, but the aggregate being deactivated happens to be the only one eligible. However, this precaution is not needed for QFQ+ to be work conserving, because update_eligible() is always invoked also at the beginning of qfq_choose_next_agg(). This patch removes the additional invocation of update_eligible() in qfq_deactivate_agg(). Signed-off-by: Paolo Valente <paolo.valente@unimore.it> Reviewed-by: Fabio Checconi <fchecconi@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-03-06pkt_sched: sch_qfq: do not allow virtual time to jump if an aggregate is in ↵Paolo Valente1-1/+2
service By definition of (the algorithm of) QFQ+, the system virtual time must be pushed up only if there is no 'eligible' aggregate, i.e. no aggregate that would have started to be served also in the ideal system emulated by QFQ+. QFQ+ serves only eligible aggregates, hence the aggregate currently in service is eligible. As a consequence, to decide whether there is no eligible aggregate, QFQ+ must also check whether there is no aggregate in service. Signed-off-by: Paolo Valente <paolo.valente@unimore.it> Reviewed-by: Fabio Checconi <fchecconi@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-03-06pkt_sched: sch_qfq: prevent budget from wrapping around after a dequeuePaolo Valente1-1/+9
Aggregate budgets are computed so as to guarantee that, after an aggregate has been selected for service, that aggregate has enough budget to serve at least one maximum-size packet for the classes it contains. For this reason, after a new aggregate has been selected for service, its next packet is immediately dequeued, without any further control. The maximum packet size for a class, lmax, can be changed through qfq_change_class(). In case the user sets lmax to a lower value than the the size of some of the still-to-arrive packets, QFQ+ will automatically push up lmax as it enqueues these packets. This automatic push up is likely to happen with TSO/GSO. In any case, if lmax is assigned a lower value than the size of some of the packets already enqueued for the class, then the following problem may occur: the size of the next packet to dequeue for the class may happen to be larger than lmax, after the aggregate to which the class belongs has been just selected for service. In this case, even the budget of the aggregate, which is an unsigned value, may be lower than the size of the next packet to dequeue. After dequeueing this packet and subtracting its size from the budget, the latter would wrap around. This fix prevents the budget from wrapping around after any packet dequeue. Signed-off-by: Paolo Valente <paolo.valente@unimore.it> Reviewed-by: Fabio Checconi <fchecconi@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-03-06pkt_sched: sch_qfq: serve activated aggregates immediately if the scheduler ↵Paolo Valente1-14/+22
is empty If no aggregate is in service, then the function qfq_dequeue() does not dequeue any packet. For this reason, to guarantee QFQ+ to be work conserving, a just-activated aggregate must be set as in service immediately if it happens to be the only active aggregate. This is done by the function qfq_enqueue(). Unfortunately, the function qfq_add_to_agg(), used to add a class to an aggregate, does not perform this important additional operation. In particular, if: 1) qfq_add_to_agg() is invoked to complete the move of a class from a source aggregate, becoming, for this move, inactive, to a destination aggregate, becoming instead active, and 2) the destination aggregate becomes the only active aggregate, then this aggregate is not however set as in service. QFQ+ remains then in a non-work-conserving state until a new invocation of qfq_enqueue() recovers the situation. This fix solves the problem by moving the logic for setting an aggregate as in service directly into the function qfq_activate_agg(). Hence, from whatever point qfq_activate_aggregate() is invoked, QFQ+ remains work conserving. Since the more-complex logic of this new version of activate_aggregate() is not necessary, in qfq_dequeue(), to reschedule an aggregate that finishes its budget, then the aggregate is now rescheduled by invoking directly the functions needed. Signed-off-by: Paolo Valente <paolo.valente@unimore.it> Reviewed-by: Fabio Checconi <fchecconi@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-03-06pkt_sched: sch_qfq: fix the update of eligible-group setsPaolo Valente1-1/+1
Between two invocations of make_eligible, the system virtual time may happen to grow enough that, in its binary representation, a bit with higher order than 31 flips. This happens especially with TSO/GSO. Before this fix, the mask used in make_eligible was computed as (1UL<<index_of_last_flipped_bit)-1, whose value is well defined on a 64-bit architecture, because index_of_flipped_bit <= 63, but is in general undefined on a 32-bit architecture if index_of_flipped_bit > 31. The fix just replaces 1UL with 1ULL. Signed-off-by: Paolo Valente <paolo.valente@unimore.it> Reviewed-by: Fabio Checconi <fchecconi@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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