| Message ID | a4a0e759b9f82a17ddd2eac68f6cd99788248683.1725845619.git.tanggeliang@kylinos.cn (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | [mptcp-next,v2,1/4] bpf: Add mptcp_subflow bpf_iter | expand |
On Mon, 2024-09-09 at 09:36 +0800, Geliang Tang wrote: > From: Geliang Tang <tanggeliang@kylinos.cn> > > It's necessary to traverse all subflows on the conn_list of an MPTCP > socket and then call kfunc to modify the fields of each subflow. In > kernel space, mptcp_for_each_subflow() helper is used for this: > > mptcp_for_each_subflow(msk, subflow) > kfunc(subflow); > > But in the MPTCP BPF program, this has not yet been implemented. As > Martin suggested recently, this conn_list walking + modify-by-kfunc > usage fits the bpf_iter use case. So this patch adds a new bpf_iter > type named "mptcp_subflow" to do this and implements its helpers > bpf_iter_mptcp_subflow_new()/_next()/_destroy(). > > Then bpf_for_each() for mptcp_subflow can be used in BPF program like > this: > > bpf_rcu_read_lock(); > bpf_for_each(mptcp_subflow, subflow, msk) > kfunc(subflow); > bpf_rcu_read_unlock(); > > Suggested-by: Martin KaFai Lau <martin.lau@kernel.org> > Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn> > --- > net/mptcp/bpf.c | 51 > ++++++++++++++++++++++++++++++++++++++++++++ > net/mptcp/protocol.h | 6 ++++++ > 2 files changed, 57 insertions(+) > > diff --git a/net/mptcp/bpf.c b/net/mptcp/bpf.c > index 9672a70c24b0..799264119891 100644 > --- a/net/mptcp/bpf.c > +++ b/net/mptcp/bpf.c > @@ -204,10 +204,59 @@ static const struct btf_kfunc_id_set > bpf_mptcp_fmodret_set = { > .set = &bpf_mptcp_fmodret_ids, > }; > > +struct bpf_iter__mptcp_subflow { > + __bpf_md_ptr(struct bpf_iter_meta *, meta); > + __bpf_md_ptr(struct mptcp_sock *, msk); > + __bpf_md_ptr(struct list_head *, pos); > +}; This bpf_iter__mptcp_subflow struct should be dropped too. > + > +struct bpf_iter_mptcp_subflow { > + __u64 __opaque[2]; > +} __attribute__((aligned(8))); > + > +struct bpf_iter_mptcp_subflow_kern { > + struct mptcp_sock *msk; > + struct list_head *pos; > +} __attribute__((aligned(8))); > + > __diag_push(); > __diag_ignore_all("-Wmissing-prototypes", > "kfuncs which will be used in BPF programs"); Duplicate with __bpf_kfunc_start_defs/__bpf_kfunc_end_defs, __diag_push, __diag_pop and __diag_ignore_all should be dropped. > > +__bpf_kfunc_start_defs(); > + > +__bpf_kfunc int bpf_iter_mptcp_subflow_new(struct > bpf_iter_mptcp_subflow *it, > + struct mptcp_sock *msk) > +{ > + struct bpf_iter_mptcp_subflow_kern *kit = (void *)it; > + > + if (!msk) > + return -EINVAL; > + > + kit->msk = msk; > + kit->pos = &msk->conn_list; > + return 0; > +} > + > +__bpf_kfunc struct mptcp_subflow_context * > +bpf_iter_mptcp_subflow_next(struct bpf_iter_mptcp_subflow *it) > +{ > + struct bpf_iter_mptcp_subflow_kern *kit = (void *)it; > + struct mptcp_subflow_context *subflow; > + struct mptcp_sock *msk = kit->msk; > + > + subflow = list_entry((kit->pos)->next, struct > mptcp_subflow_context, node); > + if (!msk || list_entry_is_head(subflow, &msk->conn_list, > node)) > + return NULL; > + > + kit->pos = &subflow->node; > + return subflow; > +} > + > +__bpf_kfunc void bpf_iter_mptcp_subflow_destroy(struct > bpf_iter_mptcp_subflow *it) > +{ > +} > + > __bpf_kfunc struct mptcp_subflow_context * > bpf_mptcp_subflow_ctx_by_pos(const struct mptcp_sched_data *data, > unsigned int pos) > { > @@ -221,6 +270,8 @@ __bpf_kfunc bool > bpf_mptcp_subflow_queues_empty(struct sock *sk) > return tcp_rtx_queue_empty(sk); > } > > +__bpf_kfunc_end_defs(); > + > __diag_pop(); > > BTF_KFUNCS_START(bpf_mptcp_sched_kfunc_ids) > diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h > index d25d2dac88a5..b3f5254e3c0d 100644 > --- a/net/mptcp/protocol.h > +++ b/net/mptcp/protocol.h > @@ -715,6 +715,12 @@ void mptcp_subflow_queue_clean(struct sock *sk, > struct sock *ssk); > void mptcp_sock_graft(struct sock *sk, struct socket *parent); > u64 mptcp_wnd_end(const struct mptcp_sock *msk); > void mptcp_set_timeout(struct sock *sk); > +struct bpf_iter_mptcp_subflow; > +int bpf_iter_mptcp_subflow_new(struct bpf_iter_mptcp_subflow *it, > + struct mptcp_sock *msk); > +struct mptcp_subflow_context * > +bpf_iter_mptcp_subflow_next(struct bpf_iter_mptcp_subflow *it); > +void bpf_iter_mptcp_subflow_destroy(struct bpf_iter_mptcp_subflow > *it); No need to add these declarations, since "-Wmissing-declarations" is ignored in __bpf_kfunc_start_defs. Will update in v3. Thanks, -Geliang > bool bpf_mptcp_subflow_queues_empty(struct sock *sk); > struct mptcp_subflow_context * > bpf_mptcp_subflow_ctx_by_pos(const struct mptcp_sched_data *data, > unsigned int pos);
diff --git a/net/mptcp/bpf.c b/net/mptcp/bpf.c index 9672a70c24b0..799264119891 100644 --- a/net/mptcp/bpf.c +++ b/net/mptcp/bpf.c @@ -204,10 +204,59 @@ static const struct btf_kfunc_id_set bpf_mptcp_fmodret_set = { .set = &bpf_mptcp_fmodret_ids, }; +struct bpf_iter__mptcp_subflow { + __bpf_md_ptr(struct bpf_iter_meta *, meta); + __bpf_md_ptr(struct mptcp_sock *, msk); + __bpf_md_ptr(struct list_head *, pos); +}; + +struct bpf_iter_mptcp_subflow { + __u64 __opaque[2]; +} __attribute__((aligned(8))); + +struct bpf_iter_mptcp_subflow_kern { + struct mptcp_sock *msk; + struct list_head *pos; +} __attribute__((aligned(8))); + __diag_push(); __diag_ignore_all("-Wmissing-prototypes", "kfuncs which will be used in BPF programs"); +__bpf_kfunc_start_defs(); + +__bpf_kfunc int bpf_iter_mptcp_subflow_new(struct bpf_iter_mptcp_subflow *it, + struct mptcp_sock *msk) +{ + struct bpf_iter_mptcp_subflow_kern *kit = (void *)it; + + if (!msk) + return -EINVAL; + + kit->msk = msk; + kit->pos = &msk->conn_list; + return 0; +} + +__bpf_kfunc struct mptcp_subflow_context * +bpf_iter_mptcp_subflow_next(struct bpf_iter_mptcp_subflow *it) +{ + struct bpf_iter_mptcp_subflow_kern *kit = (void *)it; + struct mptcp_subflow_context *subflow; + struct mptcp_sock *msk = kit->msk; + + subflow = list_entry((kit->pos)->next, struct mptcp_subflow_context, node); + if (!msk || list_entry_is_head(subflow, &msk->conn_list, node)) + return NULL; + + kit->pos = &subflow->node; + return subflow; +} + +__bpf_kfunc void bpf_iter_mptcp_subflow_destroy(struct bpf_iter_mptcp_subflow *it) +{ +} + __bpf_kfunc struct mptcp_subflow_context * bpf_mptcp_subflow_ctx_by_pos(const struct mptcp_sched_data *data, unsigned int pos) { @@ -221,6 +270,8 @@ __bpf_kfunc bool bpf_mptcp_subflow_queues_empty(struct sock *sk) return tcp_rtx_queue_empty(sk); } +__bpf_kfunc_end_defs(); + __diag_pop(); BTF_KFUNCS_START(bpf_mptcp_sched_kfunc_ids) diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h index d25d2dac88a5..b3f5254e3c0d 100644 --- a/net/mptcp/protocol.h +++ b/net/mptcp/protocol.h @@ -715,6 +715,12 @@ void mptcp_subflow_queue_clean(struct sock *sk, struct sock *ssk); void mptcp_sock_graft(struct sock *sk, struct socket *parent); u64 mptcp_wnd_end(const struct mptcp_sock *msk); void mptcp_set_timeout(struct sock *sk); +struct bpf_iter_mptcp_subflow; +int bpf_iter_mptcp_subflow_new(struct bpf_iter_mptcp_subflow *it, + struct mptcp_sock *msk); +struct mptcp_subflow_context * +bpf_iter_mptcp_subflow_next(struct bpf_iter_mptcp_subflow *it); +void bpf_iter_mptcp_subflow_destroy(struct bpf_iter_mptcp_subflow *it); bool bpf_mptcp_subflow_queues_empty(struct sock *sk); struct mptcp_subflow_context * bpf_mptcp_subflow_ctx_by_pos(const struct mptcp_sched_data *data, unsigned int pos);