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mptcp: add last time fields in mptcp_info

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This patch adds "last time" fields last_data_sent, last_data_recv and
last_ack_recv in struct mptcp_sock to record the last time data_sent,
data_recv and ack_recv happened. They all are initialized as
tcp_jiffies32 in __mptcp_init_sock(), and updated as tcp_jiffies32 too
when data is sent in __subflow_push_pending(), data is received in
__mptcp_move_skbs_from_subflow(), and ack is received in ack_update_msk().

Similar to tcpi_last_data_sent, tcpi_last_data_recv and tcpi_last_ack_recv
exposed with TCP, this patch exposes the last time "an action happened" for
MPTCP in mptcp_info, named mptcpi_last_data_sent, mptcpi_last_data_recv and
mptcpi_last_ack_recv, calculated in mptcp_diag_fill_info() as the time
deltas between now and the newly added last time fields in mptcp_sock.

Since msk->last_ack_recv needs to be protected by mptcp_data_lock/unlock,
and lock_sock_fast can sleep and be quite slow, move the entire
mptcp_data_lock/unlock block after the lock/unlock_sock_fast block.
Then mptcpi_last_data_sent and mptcpi_last_data_recv are set in
lock/unlock_sock_fast block, while mptcpi_last_ack_recv is set in
mptcp_data_lock/unlock block, which is protected by a spinlock and
should not block for too long.

Also add three reserved bytes in struct mptcp_info not to have holes in
this structure exposed to userspace.

Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/446
Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://lore.kernel.org/r/20240410-upstream-net-next-20240405-mptcp-last-time-info-v2-1-f95bd6b33e51@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Geliang Tang 2024-04-10 11:48:24 +02:00 committed by Jakub Kicinski
parent 0e36c21d76
commit 18d82cde74
5 changed files with 26 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
include/uapi/linux/mptcp.h
View File

@ -58,6 +58,10 @@ struct mptcp_info {
__u64 mptcpi_bytes_received;
__u64 mptcpi_bytes_acked;
__u8 mptcpi_subflows_total;
__u8 reserved[3];
__u32 mptcpi_last_data_sent;
__u32 mptcpi_last_data_recv;
__u32 mptcpi_last_ack_recv;
};
/* MPTCP Reset reason codes, rfc8684 */

1
net/mptcp/options.c
View File

@ -1068,6 +1068,7 @@ static void ack_update_msk(struct mptcp_sock *msk,
__mptcp_snd_una_update(msk, new_snd_una);
__mptcp_data_acked(sk);
}
msk->last_ack_recv = tcp_jiffies32;
mptcp_data_unlock(sk);
trace_ack_update_msk(mp_opt->data_ack,

7
net/mptcp/protocol.c
View File

@ -706,6 +706,8 @@ static bool __mptcp_move_skbs_from_subflow(struct mptcp_sock *msk,
}
} while (more_data_avail);
if (moved > 0)
msk->last_data_recv = tcp_jiffies32;
*bytes += moved;
return done;
}
@ -1556,6 +1558,8 @@ static int __subflow_push_pending(struct sock *sk, struct sock *ssk,
err = copied;
out:
if (err > 0)
msk->last_data_sent = tcp_jiffies32;
return err;
}
@ -2793,6 +2797,9 @@ static void __mptcp_init_sock(struct sock *sk)
WRITE_ONCE(msk->allow_infinite_fallback, true);
msk->recovery = false;
msk->subflow_id = 1;
msk->last_data_sent = tcp_jiffies32;
msk->last_data_recv = tcp_jiffies32;
msk->last_ack_recv = tcp_jiffies32;
mptcp_pm_data_init(msk);

3
net/mptcp/protocol.h
View File

@ -282,6 +282,9 @@ struct mptcp_sock {
u64 bytes_acked;
u64 snd_una;
u64 wnd_end;
u32 last_data_sent;
u32 last_data_recv;
u32 last_ack_recv;
unsigned long timer_ival;
u32 token;
int rmem_released;

16
net/mptcp/sockopt.c
View File

@ -898,6 +898,7 @@ void mptcp_diag_fill_info(struct mptcp_sock *msk, struct mptcp_info *info)
struct sock *sk = (struct sock *)msk;
u32 flags = 0;
bool slow;
u32 now;
memset(info, 0, sizeof(*info));
@ -926,11 +927,6 @@ void mptcp_diag_fill_info(struct mptcp_sock *msk, struct mptcp_info *info)
if (READ_ONCE(msk->can_ack))
flags |= MPTCP_INFO_FLAG_REMOTE_KEY_RECEIVED;
info->mptcpi_flags = flags;
mptcp_data_lock(sk);
info->mptcpi_snd_una = msk->snd_una;
info->mptcpi_rcv_nxt = msk->ack_seq;
info->mptcpi_bytes_acked = msk->bytes_acked;
mptcp_data_unlock(sk);
slow = lock_sock_fast(sk);
info->mptcpi_csum_enabled = READ_ONCE(msk->csum_enabled);
@ -942,7 +938,17 @@ void mptcp_diag_fill_info(struct mptcp_sock *msk, struct mptcp_info *info)
info->mptcpi_bytes_retrans = msk->bytes_retrans;
info->mptcpi_subflows_total = info->mptcpi_subflows +
__mptcp_has_initial_subflow(msk);
now = tcp_jiffies32;
info->mptcpi_last_data_sent = jiffies_to_msecs(now - msk->last_data_sent);
info->mptcpi_last_data_recv = jiffies_to_msecs(now - msk->last_data_recv);
unlock_sock_fast(sk, slow);
mptcp_data_lock(sk);
info->mptcpi_last_ack_recv = jiffies_to_msecs(now - msk->last_ack_recv);
info->mptcpi_snd_una = msk->snd_una;
info->mptcpi_rcv_nxt = msk->ack_seq;
info->mptcpi_bytes_acked = msk->bytes_acked;
mptcp_data_unlock(sk);
}
EXPORT_SYMBOL_GPL(mptcp_diag_fill_info);