The tc action act_gate was using shared stats, move it to percpu stats.
tdc results:
1..12
ok 1 5153 - Add gate action with priority and sched-entry
ok 2 7189 - Add gate action with base-time
ok 3 a721 - Add gate action with cycle-time
ok 4 c029 - Add gate action with cycle-time-ext
ok 5 3719 - Replace gate base-time action
ok 6 d821 - Delete gate action with valid index
ok 7 3128 - Delete gate action with invalid index
ok 8 7837 - List gate actions
ok 9 9273 - Flush gate actions
ok 10 c829 - Add gate action with duplicate index
ok 11 3043 - Add gate action with invalid index
ok 12 2930 - Add gate action with cookie
Reviewed-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Pedro Tammela <pctammela@mojatatu.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
The tc action act_connmark was using shared stats and taking the per
action lock in the datapath. Improve it by using percpu stats and rcu.
perf before:
- 13.55% tcf_connmark_act
- 81.18% _raw_spin_lock
80.46% native_queued_spin_lock_slowpath
perf after:
- 2.85% tcf_connmark_act
tdc results:
1..15
ok 1 2002 - Add valid connmark action with defaults
ok 2 56a5 - Add valid connmark action with control pass
ok 3 7c66 - Add valid connmark action with control drop
ok 4 a913 - Add valid connmark action with control pipe
ok 5 bdd8 - Add valid connmark action with control reclassify
ok 6 b8be - Add valid connmark action with control continue
ok 7 d8a6 - Add valid connmark action with control jump
ok 8 aae8 - Add valid connmark action with zone argument
ok 9 2f0b - Add valid connmark action with invalid zone argument
ok 10 9305 - Add connmark action with unsupported argument
ok 11 71ca - Add valid connmark action and replace it
ok 12 5f8f - Add valid connmark action with cookie
ok 13 c506 - Replace connmark with invalid goto chain control
ok 14 6571 - Delete connmark action with valid index
ok 15 3426 - Delete connmark action with invalid index
Reviewed-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Pedro Tammela <pctammela@mojatatu.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
The tc action act_nat was using shared stats and taking the per action
lock in the datapath. Improve it by using percpu stats and rcu.
perf before:
- 10.48% tcf_nat_act
- 81.83% _raw_spin_lock
81.08% native_queued_spin_lock_slowpath
perf after:
- 0.48% tcf_nat_act
tdc results:
1..27
ok 1 7565 - Add nat action on ingress with default control action
ok 2 fd79 - Add nat action on ingress with pipe control action
ok 3 eab9 - Add nat action on ingress with continue control action
ok 4 c53a - Add nat action on ingress with reclassify control action
ok 5 76c9 - Add nat action on ingress with jump control action
ok 6 24c6 - Add nat action on ingress with drop control action
ok 7 2120 - Add nat action on ingress with maximum index value
ok 8 3e9d - Add nat action on ingress with invalid index value
ok 9 f6c9 - Add nat action on ingress with invalid IP address
ok 10 be25 - Add nat action on ingress with invalid argument
ok 11 a7bd - Add nat action on ingress with DEFAULT IP address
ok 12 ee1e - Add nat action on ingress with ANY IP address
ok 13 1de8 - Add nat action on ingress with ALL IP address
ok 14 8dba - Add nat action on egress with default control action
ok 15 19a7 - Add nat action on egress with pipe control action
ok 16 f1d9 - Add nat action on egress with continue control action
ok 17 6d4a - Add nat action on egress with reclassify control action
ok 18 b313 - Add nat action on egress with jump control action
ok 19 d9fc - Add nat action on egress with drop control action
ok 20 a895 - Add nat action on egress with DEFAULT IP address
ok 21 2572 - Add nat action on egress with ANY IP address
ok 22 37f3 - Add nat action on egress with ALL IP address
ok 23 6054 - Add nat action on egress with cookie
ok 24 79d6 - Add nat action on ingress with cookie
ok 25 4b12 - Replace nat action with invalid goto chain control
ok 26 b811 - Delete nat action with valid index
ok 27 a521 - Delete nat action with invalid index
Reviewed-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Pedro Tammela <pctammela@mojatatu.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
The rsvp classifier has served us well for about a quarter of a century but has
has not been getting much maintenance attention due to lack of known users.
Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Acked-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
The tcindex classifier has served us well for about a quarter of a century
but has not been getting much TLC due to lack of known users. Most recently
it has become easy prey to syzkaller. For this reason, we are retiring it.
Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Acked-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
The dsmark qdisc has served us well over the years for diffserv but has not
been getting much attention due to other more popular approaches to do diffserv
services. Most recently it has become a shooting target for syzkaller. For this
reason, we are retiring it.
Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Acked-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
The ATM qdisc has served us well over the years but has not been getting much
TLC due to lack of known users. Most recently it has become a shooting target
for syzkaller. For this reason, we are retiring it.
Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Acked-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
While this amazing qdisc has served us well over the years it has not been
getting any tender love and care and has bitrotted over time.
It has become mostly a shooting target for syzkaller lately.
For this reason, we are retiring it. Goodbye CBQ - we loved you.
Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Acked-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
There are currently two mechanisms for populating hardware stats:
1. Using flow_offload api to query the flow's statistics.
The api assumes that the same stats values apply to all
the flow's actions.
This assumption breaks when action drops or jumps over following
actions.
2. Using hw_action api to query specific action stats via a driver
callback method. This api assures the correct action stats for
the offloaded action, however, it does not apply to the rest of the
actions in the flow's actions array.
Extend the flow_offload stats callback to indicate that a per action
stats update is required.
Use the existing flow_offload_action api to query the action's hw stats.
In addition, currently the tc action stats utility only updates hw actions.
Reuse the existing action stats cb infrastructure to query any action
stats.
Signed-off-by: Oz Shlomo <ozsh@nvidia.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Currently a hardware action is uniquely identified by the <id, hw_index>
tuple. However, the id is set by the flow_act_setup callback and tc core
cannot enforce this, and it is possible that a future change could break
this. In addition, <id, hw_index> are not unique across network namespaces.
Uniquely identify the action by setting an action cookie by the tc core.
Use the unique action cookie to query the action's hardware stats.
Signed-off-by: Oz Shlomo <ozsh@nvidia.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Instead of passing 6 stats related args, pass the flow_stats.
Signed-off-by: Oz Shlomo <ozsh@nvidia.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
A single tc pedit action may be translated to multiple flow_offload
actions.
Offload only actions that translate to a single pedit command value.
Signed-off-by: Oz Shlomo <ozsh@nvidia.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Currently the hw action stats update is called from tcf_exts_hw_stats_update,
when a tc filter is dumped, and from tcf_action_copy_stats, when a hw
action is dumped.
However, the tcf_action_copy_stats is also called from tcf_action_dump.
As such, the hw action stats update cb is called 3 times for every
tc flower filter dump.
Move the tc action hw stats update from tcf_action_copy_stats to
tcf_dump_walker to update the hw action stats when tc action is dumped.
Signed-off-by: Oz Shlomo <ozsh@nvidia.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
If TCA_STAB attribute is malformed, qdisc_get_stab() returns
an error, and we end up calling ops->destroy() while ops->init()
has not been called yet.
While we are at it, call qdisc_put_stab() after ops->destroy().
Fixes: 1f62879e36 ("net/sched: make stab available before ops->init() call")
Reported-by: syzbot+d44d88f1d11e6ca8576b@syzkaller.appspotmail.com
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Vladimir Oltean <vladimir.oltean@nxp.com>
Cc: Kurt Kanzenbach <kurt@linutronix.de>
Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Now handle_fragments() in OVS and TC have the similar code, and
this patch removes the duplicate code by moving the function
to nf_conntrack_ovs.
Note that skb_clear_hash(skb) or skb->ignore_df = 1 should be
done only when defrag returns 0, as it does in other places
in kernel.
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Reviewed-by: Aaron Conole <aconole@redhat.com>
Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This patch has no functional changes and just moves frag check and
tc_skb_cb update out of handle_fragments, to make it easier to move
the duplicate code from handle_fragments() into nf_conntrack_ovs later.
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
There are almost the same code in ovs_skb_network_trim() and
tcf_ct_skb_network_trim(), this patch extracts them into a function
nf_ct_skb_network_trim() and moves the function to nf_conntrack_ovs.
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Reviewed-by: Aaron Conole <aconole@redhat.com>
Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Similar to nf_nat_ovs created by Commit ebddb14049 ("net: move the
nat function to nf_nat_ovs for ovs and tc"), this patch is to create
nf_conntrack_ovs to get these functions shared by OVS and TC only.
There are nf_ct_helper() and nf_ct_add_helper() from nf_conntrak_helper
in this patch, and will be more in the following patches.
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Reviewed-by: Aaron Conole <aconole@redhat.com>
Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Improve commit 497cc00224 ("taprio: Handle short intervals and large
packets") to only perform segmentation when skb->len exceeds what
taprio_dequeue() expects.
In practice, this will make the biggest difference when a traffic class
gate is always open in the schedule. This is because the max_frm_len
will be U32_MAX, and such large skb->len values as Kurt reported will be
sent just fine unsegmented.
What I don't seem to know how to handle is how to make sure that the
segmented skbs themselves are smaller than the maximum frame size given
by the current queueMaxSDU[tc]. Nonetheless, we still need to drop
those, otherwise the Qdisc will hang.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Kurt Kanzenbach <kurt@linutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
The majority of the taprio_enqueue()'s function is spent doing TCP
segmentation, which doesn't look right to me. Compilers shouldn't have a
problem in inlining code no matter how we write it, so move the
segmentation logic to a separate function.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Kurt Kanzenbach <kurt@linutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
taprio today has a huge problem with small TC gate durations, because it
might accept packets in taprio_enqueue() which will never be sent by
taprio_dequeue().
Since not much infrastructure was available, a kludge was added in
commit 497cc00224 ("taprio: Handle short intervals and large
packets"), which segmented large TCP segments, but the fact of the
matter is that the issue isn't specific to large TCP segments (and even
worse, the performance penalty in segmenting those is absolutely huge).
In commit a54fc09e4c ("net/sched: taprio: allow user input of per-tc
max SDU"), taprio gained support for queueMaxSDU, which is precisely the
mechanism through which packets should be dropped at qdisc_enqueue() if
they cannot be sent.
After that patch, it was necessary for the user to manually limit the
maximum MTU per TC. This change adds the necessary logic for taprio to
further limit the values specified (or not specified) by the user to
some minimum values which never allow oversized packets to be sent.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Kurt Kanzenbach <kurt@linutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
I have one practical reason for doing this and one concerning correctness.
The practical reason has to do with a follow-up patch, which aims to mix
2 sources of max_sdu (one coming from the user and the other automatically
calculated based on TC gate durations @current link speed). Among those
2 sources of input, we must always select the smaller max_sdu value, but
this can change at various link speeds. So the max_sdu coming from the
user must be kept separated from the value that is operationally used
(the minimum of the 2), because otherwise we overwrite it and forget
what the user asked us to do.
To solve that, this patch proposes that struct sched_gate_list contains
the operationally active max_frm_len, and q->max_sdu contains just what
was requested by the user.
The reason having to do with correctness is based on the following
observation: the admin sched_gate_list becomes operational at a given
base_time in the future. Until then, it is inactive and applies no
shaping, all gates are open, etc. So the queueMaxSDU dropping shouldn't
apply either (this is a mechanism to ensure that packets smaller than
the largest gate duration for that TC don't hang the port; clearly it
makes little sense if the gates are always open).
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Kurt Kanzenbach <kurt@linutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Vinicius intended taprio to take the L1 overhead into account when
estimating packet transmission time through user input, specifically
through the qdisc size table (man tc-stab).
Something like this:
tc qdisc replace dev $eth root stab overhead 24 taprio \
num_tc 8 \
map 0 1 2 3 4 5 6 7 \
queues 1@0 1@1 1@2 1@3 1@4 1@5 1@6 1@7 \
base-time 0 \
sched-entry S 0x7e 9000000 \
sched-entry S 0x82 1000000 \
max-sdu 0 0 0 0 0 0 0 200 \
flags 0x0 clockid CLOCK_TAI
Without the overhead being specified, transmission times will be
underestimated and will cause late transmissions. For an offloading
driver, it might even cause TX hangs if there is no open gate large
enough to send the maximum sized packets for that TC (including L1
overhead). Properly knowing the L1 overhead will ensure that we are able
to auto-calculate the queueMaxSDU per traffic class just right, and
avoid these hangs due to head-of-line blocking.
We can't make the stab mandatory due to existing setups, but we can warn
the user that it's important with a warning netlink extack.
Link: https://patchwork.kernel.org/project/netdevbpf/patch/20220505160357.298794-1-vladimir.oltean@nxp.com/
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Kurt Kanzenbach <kurt@linutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Some qdiscs like taprio turn out to be actually pretty reliant on a well
configured stab, to not underestimate the skb transmission time (by
properly accounting for L1 overhead).
In a future change, taprio will need the stab, if configured by the
user, to be available at ops->init() time. It will become even more
important in upcoming work, when the overhead will be used for the
queueMaxSDU calculation that is passed to an offloading driver.
However, rcu_assign_pointer(sch->stab, stab) is called right after
ops->init(), making it unavailable, and I don't really see a good reason
for that.
Move it earlier, which nicely seems to simplify the error handling path
as well.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Kurt Kanzenbach <kurt@linutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
taprio_dequeue_from_txq() looks at the entry->end_time to determine
whether the skb will overrun its traffic class gate, as if at the end of
the schedule entry there surely is a "gate close" event for it. Hint:
maybe there isn't.
For each schedule entry, introduce an array of kernel times which
actually tracks when in the future will there be an *actual* gate close
event for that traffic class, and use that in the guard band overrun
calculation.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Kurt Kanzenbach <kurt@linutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently taprio assumes that the budget for a traffic class expires at
the end of the current interval as if the next interval contains a "gate
close" event for this traffic class.
This is, however, an unfounded assumption. Allow schedule entry
intervals to be fused together for a particular traffic class by
calculating the budget until the gate *actually* closes.
This means we need to keep budgets per traffic class, and we also need
to update the budget consumption procedure.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Kurt Kanzenbach <kurt@linutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
There is a confusion in terms in taprio which makes what is called
"close_time" to be actually used for 2 things:
1. determining when an entry "closes" such that transmitted skbs are
never allowed to overrun that time (?!)
2. an aid for determining when to advance and/or restart the schedule
using the hrtimer
It makes more sense to call this so-called "close_time" "end_time",
because it's not clear at all to me what "closes". Future patches will
hopefully make better use of the term "to close".
This is an absolutely mechanical change.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Kurt Kanzenbach <kurt@linutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Current taprio code operates on a very simplistic (and incorrect)
assumption: that egress scheduling for a traffic class can only take
place for the duration of the current interval, or i.o.w., it assumes
that at the end of each schedule entry, there is a "gate close" event
for all traffic classes.
As an example, traffic sent with the schedule below will be jumpy, even
though all 8 TC gates are open, so there is absolutely no "gate close"
event (effectively a transition from BIT(tc)==1 to BIT(tc)==0 in
consecutive schedule entries):
tc qdisc replace dev veth0 parent root taprio \
num_tc 2 \
map 0 1 \
queues 1@0 1@1 \
base-time 0 \
sched-entry S 0xff 4000000000 \
clockid CLOCK_TAI \
flags 0x0
This qdisc simply does not have what it takes in terms of logic to
*actually* compute the durations of traffic classes. Also, it does not
recognize the need to use this information on a per-traffic-class basis:
it always looks at entry->interval and entry->close_time.
This change proposes that each schedule entry has an array called
tc_gate_duration[tc]. This holds the information: "for how long will
this traffic class gate remain open, starting from *this* schedule
entry". If the traffic class gate is always open, that value is equal to
the cycle time of the schedule.
We'll also need to keep track, for the purpose of queueMaxSDU[tc]
calculation, what is the maximum time duration for a traffic class
having an open gate. This gives us directly what is the maximum sized
packet that this traffic class will have to accept. For everything else
it has to qdisc_drop() it in qdisc_enqueue().
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Kurt Kanzenbach <kurt@linutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Current taprio software implementation is haunted by the shadow of the
igb/igc hardware model. It iterates over child qdiscs in increasing
order of TXQ index, therefore giving higher xmit priority to TXQ 0 and
lower to TXQ N. According to discussions with Vinicius, that is the
default (perhaps even unchangeable) prioritization scheme used for the
NICs that taprio was first written for (igb, igc), and we have a case of
two bugs canceling out, resulting in a functional setup on igb/igc, but
a less sane one on other NICs.
To the best of my understanding, taprio should prioritize based on the
traffic class, so it should really dequeue starting with the highest
traffic class and going down from there. We get to the TXQ using the
tc_to_txq[] netdev property.
TXQs within the same TC have the same (strict) priority, so we should
pick from them as fairly as we can. We can achieve that by implementing
something very similar to q->curband from multiq_dequeue().
Since igb/igc really do have TXQ 0 of higher hardware priority than
TXQ 1 etc, we need to preserve the behavior for them as well. We really
have no choice, because in txtime-assist mode, taprio is essentially a
software scheduler towards offloaded child tc-etf qdiscs, so the TXQ
selection really does matter (not all igb TXQs support ETF/SO_TXTIME,
says Kurt Kanzenbach).
To preserve the behavior, we need a capability bit so that taprio can
determine if it's running on igb/igc, or on something else. Because igb
doesn't offload taprio at all, we can't piggyback on the
qdisc_offload_query_caps() call from taprio_enable_offload(), but
instead we need a separate call which is also made for software
scheduling.
Introduce two static keys to minimize the performance penalty on systems
which only have igb/igc NICs, and on systems which only have other NICs.
For mixed systems, taprio will have to dynamically check whether to
dequeue using one prioritization algorithm or using the other.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Simplify taprio_dequeue_from_txq() by noticing that we can goto one call
earlier than the previous skb_found label. This is possible because
we've unified the treatment of the child->ops->dequeue(child) return
call, we always try other TXQs now, instead of abandoning the root
dequeue completely if we failed in the peek() case.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Kurt Kanzenbach <kurt@linutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Future changes will refactor the TXQ selection procedure, and a lot of
stuff will become messy, the indentation of the bulk of the dequeue
procedure would increase, etc.
Break out the bulk of the function into a new one, which knows the TXQ
(child qdisc) we should perform a dequeue from.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Kurt Kanzenbach <kurt@linutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
This changes the handling of an unlikely condition to not stop dequeuing
if taprio failed to dequeue the peeked skb in taprio_dequeue().
I've no idea when this can happen, but the only side effect seems to be
that the atomic_sub_return() call right above will have consumed some
budget. This isn't a big deal, since either that made us remain without
any budget (and therefore, we'd exit on the next peeked skb anyway), or
we could send some packets from other TXQs.
I'm making this change because in a future patch I'll be refactoring the
dequeue procedure to simplify it, and this corner case will have to go
away.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Kurt Kanzenbach <kurt@linutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
There isn't any code in the network stack which calls taprio_peek().
We only see qdisc->ops->peek() being called on child qdiscs of other
classful qdiscs, never from the generic qdisc code. Whereas taprio is
never a child qdisc, it is always root.
This snippet of a comment from qdisc_peek_dequeued() seems to confirm:
/* we can reuse ->gso_skb because peek isn't called for root qdiscs */
Since I've been known to be wrong many times though, I'm not completely
removing it, but leaving a stub function in place which emits a warning.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Kurt Kanzenbach <kurt@linutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
The > needs be >= to prevent an out of bounds access.
Fixes: de5ca4c385 ("net: sched: sch: Bounds check priority")
Signed-off-by: Dan Carpenter <error27@gmail.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/Y+D+KN18FQI2DKLq@kili
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
There are 2 classes of in-tree drivers currently:
- those who act upon struct tc_taprio_sched_entry :: gate_mask as if it
holds a bit mask of TXQs
- those who act upon the gate_mask as if it holds a bit mask of TCs
When it comes to the standard, IEEE 802.1Q-2018 does say this in the
second paragraph of section 8.6.8.4 Enhancements for scheduled traffic:
| A gate control list associated with each Port contains an ordered list
| of gate operations. Each gate operation changes the transmission gate
| state for the gate associated with each of the Port's traffic class
| queues and allows associated control operations to be scheduled.
In typically obtuse language, it refers to a "traffic class queue"
rather than a "traffic class" or a "queue". But careful reading of
802.1Q clarifies that "traffic class" and "queue" are in fact
synonymous (see 8.6.6 Queuing frames):
| A queue in this context is not necessarily a single FIFO data structure.
| A queue is a record of all frames of a given traffic class awaiting
| transmission on a given Bridge Port. The structure of this record is not
| specified.
i.o.w. their definition of "queue" isn't the Linux TX queue.
The gate_mask really is input into taprio via its UAPI as a mask of
traffic classes, but taprio_sched_to_offload() converts it into a TXQ
mask.
The breakdown of drivers which handle TC_SETUP_QDISC_TAPRIO is:
- hellcreek, felix, sja1105: these are DSA switches, it's not even very
clear what TXQs correspond to, other than purely software constructs.
Only the mqprio configuration with 8 TCs and 1 TXQ per TC makes sense.
So it's fine to convert these to a gate mask per TC.
- enetc: I have the hardware and can confirm that the gate mask is per
TC, and affects all TXQs (BD rings) configured for that priority.
- igc: in igc_save_qbv_schedule(), the gate_mask is clearly interpreted
to be per-TXQ.
- tsnep: Gerhard Engleder clarifies that even though this hardware
supports at most 1 TXQ per TC, the TXQ indices may be different from
the TC values themselves, and it is the TXQ indices that matter to
this hardware. So keep it per-TXQ as well.
- stmmac: I have a GMAC datasheet, and in the EST section it does
specify that the gate events are per TXQ rather than per TC.
- lan966x: again, this is a switch, and while not a DSA one, the way in
which it implements lan966x_mqprio_add() - by only allowing num_tc ==
NUM_PRIO_QUEUES (8) - makes it clear to me that TXQs are a purely
software construct here as well. They seem to map 1:1 with TCs.
- am65_cpsw: from looking at am65_cpsw_est_set_sched_cmds(), I get the
impression that the fetch_allow variable is treated like a prio_mask.
This definitely sounds closer to a per-TC gate mask rather than a
per-TXQ one, and TI documentation does seem to recomment an identity
mapping between TCs and TXQs. However, Roger Quadros would like to do
some testing before making changes, so I'm leaving this driver to
operate as it did before, for now. Link with more details at the end.
Based on this breakdown, we have 5 drivers with a gate mask per TC and
4 with a gate mask per TXQ. So let's make the gate mask per TXQ the
opt-in and the gate mask per TC the default.
Benefit from the TC_QUERY_CAPS feature that Jakub suggested we add, and
query the device driver before calling the proper ndo_setup_tc(), and
figure out if it expects one or the other format.
Link: https://patchwork.kernel.org/project/netdevbpf/patch/20230202003621.2679603-15-vladimir.oltean@nxp.com/#25193204
Cc: Horatiu Vultur <horatiu.vultur@microchip.com>
Cc: Siddharth Vadapalli <s-vadapalli@ti.com>
Cc: Roger Quadros <rogerq@kernel.org>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Acked-by: Kurt Kanzenbach <kurt@linutronix.de> # hellcreek
Reviewed-by: Gerhard Engleder <gerhard@engleder-embedded.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The taprio qdisc does not currently pass the mqprio queue configuration
down to the offloading device driver. So the driver cannot act upon the
TXQ counts/offsets per TC, or upon the prio->tc map. It was probably
assumed that the driver only wants to offload num_tc (see
TC_MQPRIO_HW_OFFLOAD_TCS), which it can get from netdev_get_num_tc(),
but there's clearly more to the mqprio configuration than that.
I've considered 2 mechanisms to remedy that. First is to pass a struct
tc_mqprio_qopt_offload as part of the tc_taprio_qopt_offload. The second
is to make taprio actually call TC_SETUP_QDISC_MQPRIO, *in addition to*
TC_SETUP_QDISC_TAPRIO.
The difference is that in the first case, existing drivers (offloading
or not) all ignore taprio's mqprio portion currently, whereas in the
second case, we could control whether to call TC_SETUP_QDISC_MQPRIO,
based on a new capability. The question is which approach would be
better.
I'm afraid that calling TC_SETUP_QDISC_MQPRIO unconditionally (not based
on a taprio capability bit) would risk introducing regressions. For
example, taprio doesn't populate (or validate) qopt->hw, as well as
mqprio.flags, mqprio.shaper, mqprio.min_rate, mqprio.max_rate.
In comparison, adding a capability is functionally equivalent to just
passing the mqprio in a way that drivers can ignore it, except it's
slightly more complicated to use it (need to set the capability).
Ultimately, what made me go for the "mqprio in taprio" variant was that
it's easier for offloading drivers to interpret the mqprio qopt slightly
differently when it comes from taprio vs when it comes from mqprio,
should that ever become necessary.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The taprio qdisc will need to reconstruct a struct tc_mqprio_qopt from
netdev settings once more in a future patch, but this code was already
written twice, once in taprio and once in mqprio.
Refactor the code to a helper in the common mqprio library.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
There is a lot of code in taprio which is "borrowed" from mqprio.
It makes sense to put a stop to the "borrowing" and start actually
reusing code.
Because taprio and mqprio are built as part of different kernel modules,
code reuse can only take place either by writing it as static inline
(limiting), putting it in sch_generic.o (not generic enough), or
creating a third auto-selectable kernel module which only holds library
code. I opted for the third variant.
In a previous change, mqprio gained support for reverse TC:TXQ mappings,
something which taprio still denies. Make taprio use the same validation
logic so that it supports this configuration as well.
The taprio code didn't enforce TXQ overlaps in txtime-assist mode and
that looks intentional, even if I've no idea why that might be. Preserve
that, but add a comment.
There isn't any dedicated MAINTAINERS entry for mqprio, so nothing to
update there.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Reviewed-by: Gerhard Engleder <gerhard@engleder-embedded.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
To make mqprio more user-friendly, create netlink extended ack messages
which say exactly what is wrong about the queue counts. This uses the
new support for printf-formatted extack messages.
Example:
$ tc qdisc add dev eno0 root handle 1: mqprio num_tc 8 \
map 0 1 2 3 4 5 6 7 queues 3@0 1@1 1@2 1@3 1@4 1@5 1@6 1@7 hw 0
Error: sch_mqprio: TC 0 queues 3@0 overlap with TC 1 queues 1@1.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
mqprio_parse_opt() proudly has a comment:
/* If hardware offload is requested we will leave it to the device
* to either populate the queue counts itself or to validate the
* provided queue counts.
*/
Unfortunately some device drivers did not get this memo, and don't
validate the queue counts, or populate them.
In case drivers don't want to populate the queue counts themselves, just
act upon the requested configuration, it makes sense to introduce a tc
capability, and make mqprio query it, so they don't have to do the
validation themselves.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
By imposing that the last TXQ of TC i is smaller than the first TXQ of
any TC j (j := i+1 .. n), mqprio imposes a strict ordering condition for
the TXQ indices (they must increase as TCs increase).
Claudiu points out that the complexity of the TXQ count validation is
too high for this logic, i.e. instead of iterating over j, it is
sufficient that the TXQ indices of TC i and i + 1 are ordered, and that
will eventually ensure global ordering.
This is true, however it doesn't appear to me that is what the code
really intended to do. Instead, based on the comments, it just wanted to
check for overlaps (and this isn't how one does that).
So the following mqprio configuration, which I had recommended to
Vinicius more than once for igb/igc (to account for the fact that on
this hardware, lower numbered TXQs have higher dequeue priority than
higher ones):
num_tc 4 map 0 1 2 3 queues 1@3 1@2 1@1 1@0
is in fact denied today by mqprio.
The full story is that in fact, it's only denied with "hw 0"; if
hardware offloading is requested, mqprio defers TXQ range overlap
validation to the device driver (a strange decision in itself).
This is most certainly a bug, but it's not one that has any merit for
being fixed on "stable" as far as I can tell. This is because mqprio
always rejected a configuration which was in fact valid, and this has
shaped the way in which mqprio configuration scripts got built for
various hardware (see igb/igc in the link below). Therefore, one could
consider it to be merely an improvement for mqprio to allow reverse
TC:TXQ mappings.
Link: https://patchwork.kernel.org/project/netdevbpf/patch/20230130173145.475943-9-vladimir.oltean@nxp.com/#25188310
Link: https://patchwork.kernel.org/project/netdevbpf/patch/20230128010719.2182346-6-vladimir.oltean@nxp.com/#25186442
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Reviewed-by: Gerhard Engleder <gerhard@engleder-embedded.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Some more logic will be added to mqprio offloading, so split that code
up from mqprio_init(), which is already large, and create a new
function, mqprio_enable_offload(), similar to taprio_enable_offload().
Also create the opposite function mqprio_disable_offload().
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
mqprio_init() is quite large and unwieldy to add more code to.
Split the netlink attribute parsing to a dedicated function.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Modify the offload algorithm of UDP connections to the following:
- Offload NEW connection as unidirectional.
- When connection state changes to ESTABLISHED also update the hardware
flow. However, in order to prevent act_ct from spamming offload add wq for
every packet coming in reply direction in this state verify whether
connection has already been updated to ESTABLISHED in the drivers. If that
it the case, then skip flow_table and let conntrack handle such packets
which will also allow conntrack to potentially promote the connection to
ASSURED.
- When connection state changes to ASSURED set the flow_table flow
NF_FLOW_HW_BIDIRECTIONAL flag which will cause refresh mechanism to offload
the reply direction.
All other protocols have their offload algorithm preserved and are always
offloaded as bidirectional.
Note that this change tries to minimize the load on flow_table add
workqueue. First, it tracks the last ctinfo that was offloaded by using new
flow 'NF_FLOW_HW_ESTABLISHED' flag and doesn't schedule the refresh for
reply direction packets when the offloads have already been updated with
current ctinfo. Second, when 'add' task executes on workqueue it always
update the offload with current flow state (by checking 'bidirectional'
flow flag and obtaining actual ctinfo/cookie through meta action instead of
caching any of these from the moment of scheduling the 'add' work)
preventing the need from scheduling more updates if state changed
concurrently while the 'add' work was pending on workqueue.
Signed-off-by: Vlad Buslov <vladbu@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently tcf_ct_flow_table_fill_actions() function assumes that only
established connections can be offloaded and always sets ctinfo to either
IP_CT_ESTABLISHED or IP_CT_ESTABLISHED_REPLY strictly based on direction
without checking actual connection state. To enable UDP NEW connection
offload set the ctinfo, metadata cookie and NF_FLOW_HW_ESTABLISHED
flow_offload flags bit based on ct->status value.
Signed-off-by: Vlad Buslov <vladbu@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Modify flow table offload to cache the last ct info status that was passed
to the driver offload callbacks by extending enum nf_flow_flags with new
"NF_FLOW_HW_ESTABLISHED" flag. Set the flag if ctinfo was 'established'
during last act_ct meta actions fill call. This infrastructure change is
necessary to optimize promoting of UDP connections from 'new' to
'established' in following patches in this series.
Signed-off-by: Vlad Buslov <vladbu@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Remove the check for a negative number of keys as
this cannot ever happen
Reviewed-by: Jamal Hadi Salim <jhs@mojatatu.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: Pedro Tammela <pctammela@mojatatu.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
The software pedit action didn't get the same love as some of the
other actions and it's still using spinlocks and shared stats in the
datapath.
Transition the action to rcu and percpu stats as this improves the
action's performance dramatically on multiple cpu deployments.
Reviewed-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Pedro Tammela <pctammela@mojatatu.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
