Age | Commit message (Collapse) | Author |
|
Use BTF_ID_LIST_SINGLE(a, b, c) instead of
BTF_ID_LIST(a)
BTF_ID(b, c)
Signed-off-by: Feng Yang <yangfeng@kylinos.cn>
Link: https://lore.kernel.org/r/20250710055419.70544-1-yangfeng59949@163.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
|
|
The patch makes all currently supported Qdisc_ops (i.e., .enqueue,
.dequeue, .init, .reset, and .destroy) mandatory.
Make .init, .reset and .destroy mandatory as bpf qdisc relies on prologue
and epilogue to check attach points and correctly initialize/cleanup
resources. The prologue/epilogue will only be generated for an struct_ops
operator only if users implement the operator.
Make .enqueue and .dequeue mandatory as bpf qdisc infra does not provide
a default data path.
Fixes: c8240344956e ("bpf: net_sched: Support implementation of Qdisc_ops in bpf")
Signed-off-by: Amery Hung <ameryhung@gmail.com>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
|
|
Allow .init to proceed if qdisc_lookup() returns NULL as it only happens
when called by qdisc_create_dflt() in mq/mqprio_init and the parent qdisc
has not been added to qdisc_hash yet. In qdisc_create(), the caller,
__tc_modify_qdisc(), would have made sure the parent qdisc already exist.
In addition, call qdisc_watchdog_init() whether .init succeeds or not to
prevent null-pointer dereference. In qdisc_create() and
qdisc_create_dflt(), if .init fails, .destroy will be called. As a
result, the destroy epilogue could call qdisc_watchdog_cancel() with an
uninitialized timer, causing null-pointer deference in hrtimer_cancel().
Fixes: c8240344956e ("bpf: net_sched: Support implementation of Qdisc_ops in bpf")
Signed-off-by: Amery Hung <ameryhung@gmail.com>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
|
|
Do not allow users to attach bpf qdiscs to classful qdiscs. This is to
prevent accidentally breaking existings classful qdiscs if they rely on
some data in the child qdisc. This restriction can potentially be lifted
in the future. Note that, we still allow bpf qdisc to be attached to mq.
Signed-off-by: Amery Hung <ameryhung@gmail.com>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://patch.msgid.link/20250409214606.2000194-7-ameryhung@gmail.com
|
|
Add a kfunc to update Qdisc bstats when an skb is dequeued. The kfunc is
only available in .dequeue programs.
Signed-off-by: Amery Hung <amery.hung@bytedance.com>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://patch.msgid.link/20250409214606.2000194-6-ameryhung@gmail.com
|
|
Add a watchdog timer to bpf qdisc. The watchdog can be used to schedule
the execution of qdisc through kfunc, bpf_qdisc_schedule(). It can be
useful for building traffic shaping scheduling algorithm, where the time
the next packet will be dequeued is known.
The implementation relies on struct_ops gen_prologue/epilogue to patch bpf
programs provided by users. Operator specific prologue/epilogue kfuncs
are introduced instead of watchdog kfuncs so that it is easier to extend
prologue/epilogue in the future (writing C vs BPF bytecode).
Signed-off-by: Amery Hung <amery.hung@bytedance.com>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://patch.msgid.link/20250409214606.2000194-5-ameryhung@gmail.com
|
|
Add basic kfuncs for working on skb in qdisc.
Both bpf_qdisc_skb_drop() and bpf_kfree_skb() can be used to release
a reference to an skb. However, bpf_qdisc_skb_drop() can only be called
in .enqueue where a to_free skb list is available from kernel to defer
the release. bpf_kfree_skb() should be used elsewhere. It is also used
in bpf_obj_free_fields() when cleaning up skb in maps and collections.
bpf_skb_get_hash() returns the flow hash of an skb, which can be used
to build flow-based queueing algorithms.
Finally, allow users to create read-only dynptr via bpf_dynptr_from_skb().
Signed-off-by: Amery Hung <amery.hung@bytedance.com>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://patch.msgid.link/20250409214606.2000194-4-ameryhung@gmail.com
|
|
The recent advancement in bpf such as allocated objects, bpf list and bpf
rbtree has provided powerful and flexible building blocks to realize
sophisticated packet scheduling algorithms. As struct_ops now supports
core operators in Qdisc_ops, start allowing qdisc to be implemented using
bpf struct_ops with this patch. Users can implement Qdisc_ops.{enqueue,
dequeue, init, reset, destroy} in bpf and register the qdisc dynamically
into the kernel.
Co-developed-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Amery Hung <amery.hung@bytedance.com>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Acked-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://patch.msgid.link/20250409214606.2000194-3-ameryhung@gmail.com
|