diff options
author | Paolo Abeni <pabeni@redhat.com> | 2022-01-07 01:20:22 +0100 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2022-01-07 12:27:07 +0100 |
commit | 86e39e04482b0aadf3ee3ed5fcf2d63816559d36 (patch) | |
tree | 6cfe59b1db6b182614fa7824e192ad144e05b363 /net/mptcp | |
parent | mptcp: clean-up MPJ option writing (diff) | |
download | linux-86e39e04482b0aadf3ee3ed5fcf2d63816559d36.tar.xz linux-86e39e04482b0aadf3ee3ed5fcf2d63816559d36.zip |
mptcp: keep track of local endpoint still available for each msk
Include into the path manager status a bitmap tracking the list
of local endpoints still available - not yet used - for the
relevant mptcp socket.
Keep such map updated at endpoint creation/deletion time, so
that we can easily skip already used endpoint at local address
selection time.
The endpoint used by the initial subflow is lazyly accounted at
subflow creation time: the usage bitmap is be up2date before
endpoint selection and we avoid such unneeded task in some relevant
scenarios - e.g. busy servers accepting incoming subflows but
not creating any additional ones nor annuncing additional addresses.
Overall this allows for fair local endpoints usage in case of
subflow failure.
As a side effect, this patch also enforces that each endpoint
is used at most once for each mptcp connection.
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/mptcp')
-rw-r--r-- | net/mptcp/pm.c | 1 | ||||
-rw-r--r-- | net/mptcp/pm_netlink.c | 125 | ||||
-rw-r--r-- | net/mptcp/protocol.c | 3 | ||||
-rw-r--r-- | net/mptcp/protocol.h | 12 |
4 files changed, 87 insertions, 54 deletions
diff --git a/net/mptcp/pm.c b/net/mptcp/pm.c index 6b2bfe89d445..e9ba9551832c 100644 --- a/net/mptcp/pm.c +++ b/net/mptcp/pm.c @@ -370,6 +370,7 @@ void mptcp_pm_data_reset(struct mptcp_sock *msk) WRITE_ONCE(msk->pm.accept_subflow, false); WRITE_ONCE(msk->pm.remote_deny_join_id0, false); msk->pm.status = 0; + bitmap_fill(msk->pm.id_avail_bitmap, MPTCP_PM_MAX_ADDR_ID + 1); mptcp_pm_nl_data_init(msk); } diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c index 27427aeeee0e..ad3dc9c6c531 100644 --- a/net/mptcp/pm_netlink.c +++ b/net/mptcp/pm_netlink.c @@ -38,10 +38,6 @@ struct mptcp_pm_add_entry { u8 retrans_times; }; -/* max value of mptcp_addr_info.id */ -#define MAX_ADDR_ID U8_MAX -#define BITMAP_SZ DIV_ROUND_UP(MAX_ADDR_ID + 1, BITS_PER_LONG) - struct pm_nl_pernet { /* protects pernet updates */ spinlock_t lock; @@ -53,14 +49,14 @@ struct pm_nl_pernet { unsigned int local_addr_max; unsigned int subflows_max; unsigned int next_id; - unsigned long id_bitmap[BITMAP_SZ]; + DECLARE_BITMAP(id_bitmap, MPTCP_PM_MAX_ADDR_ID + 1); }; #define MPTCP_PM_ADDR_MAX 8 #define ADD_ADDR_RETRANS_MAX 3 static bool addresses_equal(const struct mptcp_addr_info *a, - struct mptcp_addr_info *b, bool use_port) + const struct mptcp_addr_info *b, bool use_port) { bool addr_equals = false; @@ -174,6 +170,9 @@ select_local_address(const struct pm_nl_pernet *pernet, if (!(entry->flags & MPTCP_PM_ADDR_FLAG_SUBFLOW)) continue; + if (!test_bit(entry->addr.id, msk->pm.id_avail_bitmap)) + continue; + if (entry->addr.family != sk->sk_family) { #if IS_ENABLED(CONFIG_MPTCP_IPV6) if ((entry->addr.family == AF_INET && @@ -184,23 +183,17 @@ select_local_address(const struct pm_nl_pernet *pernet, continue; } - /* avoid any address already in use by subflows and - * pending join - */ - if (!lookup_subflow_by_saddr(&msk->conn_list, &entry->addr)) { - ret = entry; - break; - } + ret = entry; + break; } rcu_read_unlock(); return ret; } static struct mptcp_pm_addr_entry * -select_signal_address(struct pm_nl_pernet *pernet, unsigned int pos) +select_signal_address(struct pm_nl_pernet *pernet, struct mptcp_sock *msk) { struct mptcp_pm_addr_entry *entry, *ret = NULL; - int i = 0; rcu_read_lock(); /* do not keep any additional per socket state, just signal @@ -209,12 +202,14 @@ select_signal_address(struct pm_nl_pernet *pernet, unsigned int pos) * can lead to additional addresses not being announced. */ list_for_each_entry_rcu(entry, &pernet->local_addr_list, list) { + if (!test_bit(entry->addr.id, msk->pm.id_avail_bitmap)) + continue; + if (!(entry->flags & MPTCP_PM_ADDR_FLAG_SIGNAL)) continue; - if (i++ == pos) { - ret = entry; - break; - } + + ret = entry; + break; } rcu_read_unlock(); return ret; @@ -258,9 +253,11 @@ EXPORT_SYMBOL_GPL(mptcp_pm_get_local_addr_max); static void check_work_pending(struct mptcp_sock *msk) { - if (msk->pm.add_addr_signaled == mptcp_pm_get_add_addr_signal_max(msk) && - (msk->pm.local_addr_used == mptcp_pm_get_local_addr_max(msk) || - msk->pm.subflows == mptcp_pm_get_subflows_max(msk))) + struct pm_nl_pernet *pernet = net_generic(sock_net((struct sock *)msk), pm_nl_pernet_id); + + if (msk->pm.subflows == mptcp_pm_get_subflows_max(msk) || + (find_next_and_bit(pernet->id_bitmap, msk->pm.id_avail_bitmap, + MPTCP_PM_MAX_ADDR_ID + 1, 0) == MPTCP_PM_MAX_ADDR_ID + 1)) WRITE_ONCE(msk->pm.work_pending, false); } @@ -460,6 +457,35 @@ static unsigned int fill_remote_addresses_vec(struct mptcp_sock *msk, bool fullm return i; } +static struct mptcp_pm_addr_entry * +__lookup_addr_by_id(struct pm_nl_pernet *pernet, unsigned int id) +{ + struct mptcp_pm_addr_entry *entry; + + list_for_each_entry(entry, &pernet->local_addr_list, list) { + if (entry->addr.id == id) + return entry; + } + return NULL; +} + +static int +lookup_id_by_addr(struct pm_nl_pernet *pernet, const struct mptcp_addr_info *addr) +{ + struct mptcp_pm_addr_entry *entry; + int ret = -1; + + rcu_read_lock(); + list_for_each_entry(entry, &pernet->local_addr_list, list) { + if (addresses_equal(&entry->addr, addr, entry->addr.port)) { + ret = entry->addr.id; + break; + } + } + rcu_read_unlock(); + return ret; +} + static void mptcp_pm_create_subflow_or_signal_addr(struct mptcp_sock *msk) { struct sock *sk = (struct sock *)msk; @@ -475,6 +501,19 @@ static void mptcp_pm_create_subflow_or_signal_addr(struct mptcp_sock *msk) local_addr_max = mptcp_pm_get_local_addr_max(msk); subflows_max = mptcp_pm_get_subflows_max(msk); + /* do lazy endpoint usage accounting for the MPC subflows */ + if (unlikely(!(msk->pm.status & BIT(MPTCP_PM_MPC_ENDPOINT_ACCOUNTED))) && msk->first) { + struct mptcp_addr_info local; + int mpc_id; + + local_address((struct sock_common *)msk->first, &local); + mpc_id = lookup_id_by_addr(pernet, &local); + if (mpc_id < 0) + __clear_bit(mpc_id, msk->pm.id_avail_bitmap); + + msk->pm.status |= BIT(MPTCP_PM_MPC_ENDPOINT_ACCOUNTED); + } + pr_debug("local %d:%d signal %d:%d subflows %d:%d\n", msk->pm.local_addr_used, local_addr_max, msk->pm.add_addr_signaled, add_addr_signal_max, @@ -482,21 +521,16 @@ static void mptcp_pm_create_subflow_or_signal_addr(struct mptcp_sock *msk) /* check first for announce */ if (msk->pm.add_addr_signaled < add_addr_signal_max) { - local = select_signal_address(pernet, - msk->pm.add_addr_signaled); + local = select_signal_address(pernet, msk); if (local) { if (mptcp_pm_alloc_anno_list(msk, local)) { + __clear_bit(local->addr.id, msk->pm.id_avail_bitmap); msk->pm.add_addr_signaled++; mptcp_pm_announce_addr(msk, &local->addr, false); mptcp_pm_nl_addr_send_ack(msk); } - } else { - /* pick failed, avoid fourther attempts later */ - msk->pm.local_addr_used = add_addr_signal_max; } - - check_work_pending(msk); } /* check if should create a new subflow */ @@ -510,19 +544,16 @@ static void mptcp_pm_create_subflow_or_signal_addr(struct mptcp_sock *msk) int i, nr; msk->pm.local_addr_used++; - check_work_pending(msk); nr = fill_remote_addresses_vec(msk, fullmesh, addrs); + if (nr) + __clear_bit(local->addr.id, msk->pm.id_avail_bitmap); spin_unlock_bh(&msk->pm.lock); for (i = 0; i < nr; i++) __mptcp_subflow_connect(sk, &local->addr, &addrs[i]); spin_lock_bh(&msk->pm.lock); - return; } - - /* lookup failed, avoid fourther attempts later */ - msk->pm.local_addr_used = local_addr_max; - check_work_pending(msk); } + check_work_pending(msk); } static void mptcp_pm_nl_fully_established(struct mptcp_sock *msk) @@ -736,6 +767,7 @@ static void mptcp_pm_nl_rm_addr_or_subflow(struct mptcp_sock *msk, msk->pm.subflows--; __MPTCP_INC_STATS(sock_net(sk), rm_type); } + __set_bit(rm_list->ids[1], msk->pm.id_avail_bitmap); if (!removed) continue; @@ -765,6 +797,9 @@ void mptcp_pm_nl_work(struct mptcp_sock *msk) msk_owned_by_me(msk); + if (!(pm->status & MPTCP_PM_WORK_MASK)) + return; + spin_lock_bh(&msk->pm.lock); pr_debug("msk=%p status=%x", msk, pm->status); @@ -810,7 +845,7 @@ static int mptcp_pm_nl_append_new_local_addr(struct pm_nl_pernet *pernet, /* to keep the code simple, don't do IDR-like allocation for address ID, * just bail when we exceed limits */ - if (pernet->next_id == MAX_ADDR_ID) + if (pernet->next_id == MPTCP_PM_MAX_ADDR_ID) pernet->next_id = 1; if (pernet->addrs >= MPTCP_PM_ADDR_MAX) goto out; @@ -830,7 +865,7 @@ static int mptcp_pm_nl_append_new_local_addr(struct pm_nl_pernet *pernet, if (!entry->addr.id) { find_next: entry->addr.id = find_next_zero_bit(pernet->id_bitmap, - MAX_ADDR_ID + 1, + MPTCP_PM_MAX_ADDR_ID + 1, pernet->next_id); if (!entry->addr.id && pernet->next_id != 1) { pernet->next_id = 1; @@ -1197,18 +1232,6 @@ static int mptcp_nl_cmd_add_addr(struct sk_buff *skb, struct genl_info *info) return 0; } -static struct mptcp_pm_addr_entry * -__lookup_addr_by_id(struct pm_nl_pernet *pernet, unsigned int id) -{ - struct mptcp_pm_addr_entry *entry; - - list_for_each_entry(entry, &pernet->local_addr_list, list) { - if (entry->addr.id == id) - return entry; - } - return NULL; -} - int mptcp_pm_get_flags_and_ifindex_by_id(struct net *net, unsigned int id, u8 *flags, int *ifindex) { @@ -1467,7 +1490,7 @@ static int mptcp_nl_cmd_flush_addrs(struct sk_buff *skb, struct genl_info *info) list_splice_init(&pernet->local_addr_list, &free_list); __reset_counters(pernet); pernet->next_id = 1; - bitmap_zero(pernet->id_bitmap, MAX_ADDR_ID + 1); + bitmap_zero(pernet->id_bitmap, MPTCP_PM_MAX_ADDR_ID + 1); spin_unlock_bh(&pernet->lock); mptcp_nl_remove_addrs_list(sock_net(skb->sk), &free_list); synchronize_rcu(); @@ -1577,7 +1600,7 @@ static int mptcp_nl_cmd_dump_addrs(struct sk_buff *msg, pernet = net_generic(net, pm_nl_pernet_id); spin_lock_bh(&pernet->lock); - for (i = id; i < MAX_ADDR_ID + 1; i++) { + for (i = id; i < MPTCP_PM_MAX_ADDR_ID + 1; i++) { if (test_bit(i, pernet->id_bitmap)) { entry = __lookup_addr_by_id(pernet, i); if (!entry) diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c index 667e153e6e24..5c956a8dc714 100644 --- a/net/mptcp/protocol.c +++ b/net/mptcp/protocol.c @@ -2488,8 +2488,7 @@ static void mptcp_worker(struct work_struct *work) mptcp_check_fastclose(msk); - if (msk->pm.status) - mptcp_pm_nl_work(msk); + mptcp_pm_nl_work(msk); if (test_and_clear_bit(MPTCP_WORK_EOF, &msk->flags)) mptcp_check_for_eof(msk); diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h index 386d1a98ff1d..2a6f0960ba27 100644 --- a/net/mptcp/protocol.h +++ b/net/mptcp/protocol.h @@ -173,16 +173,25 @@ enum mptcp_pm_status { MPTCP_PM_ADD_ADDR_SEND_ACK, MPTCP_PM_RM_ADDR_RECEIVED, MPTCP_PM_ESTABLISHED, - MPTCP_PM_ALREADY_ESTABLISHED, /* persistent status, set after ESTABLISHED event */ MPTCP_PM_SUBFLOW_ESTABLISHED, + MPTCP_PM_ALREADY_ESTABLISHED, /* persistent status, set after ESTABLISHED event */ + MPTCP_PM_MPC_ENDPOINT_ACCOUNTED /* persistent status, set after MPC local address is + * accounted int id_avail_bitmap + */ }; +/* Status bits below MPTCP_PM_ALREADY_ESTABLISHED need pm worker actions */ +#define MPTCP_PM_WORK_MASK ((1 << MPTCP_PM_ALREADY_ESTABLISHED) - 1) + enum mptcp_addr_signal_status { MPTCP_ADD_ADDR_SIGNAL, MPTCP_ADD_ADDR_ECHO, MPTCP_RM_ADDR_SIGNAL, }; +/* max value of mptcp_addr_info.id */ +#define MPTCP_PM_MAX_ADDR_ID U8_MAX + struct mptcp_pm_data { struct mptcp_addr_info local; struct mptcp_addr_info remote; @@ -201,6 +210,7 @@ struct mptcp_pm_data { u8 local_addr_used; u8 subflows; u8 status; + DECLARE_BITMAP(id_avail_bitmap, MPTCP_PM_MAX_ADDR_ID + 1); struct mptcp_rm_list rm_list_tx; struct mptcp_rm_list rm_list_rx; }; |