* [PATCH bpf-next v1 1/2] bpf: add mrtt and srtt as BPF_SOCK_OPS_RTT_CB args
2024-04-25 16:17 [PATCH bpf-next v1 0/2] bpf: add mrtt and srtt as ctx->args for BPF_SOCK_OPS_RTT_CB Philo Lu
@ 2024-04-25 16:17 ` Philo Lu
2024-04-25 16:17 ` [PATCH bpf-next v1 2/2] selftests/bpf: extend BPF_SOCK_OPS_RTT_CB test for srtt and mrtt_us Philo Lu
2024-04-25 22:10 ` [PATCH bpf-next v1 0/2] bpf: add mrtt and srtt as ctx->args for BPF_SOCK_OPS_RTT_CB patchwork-bot+netdevbpf
2 siblings, 0 replies; 4+ messages in thread
From: Philo Lu @ 2024-04-25 16:17 UTC (permalink / raw)
To: bpf
Cc: edumazet, davem, kuba, pabeni, ast, daniel, andrii, martin.lau,
eddyz87, song, yonghong.song, john.fastabend, kpsingh, sdf,
haoluo, jolsa, dsahern, mykolal, shuah, laoar.shao, fred.cc,
xuanzhuo
Two important arguments in RTT estimation, mrtt and srtt, are passed to
tcp_bpf_rtt(), so that bpf programs get more information about RTT
computation in BPF_SOCK_OPS_RTT_CB.
The difference between bpf_sock_ops->srtt_us and the srtt here is: the
former is an old rtt before update, while srtt passed by tcp_bpf_rtt()
is that after update.
Signed-off-by: Philo Lu <lulie@linux.alibaba.com>
---
include/net/tcp.h | 4 ++--
include/uapi/linux/bpf.h | 2 ++
net/ipv4/tcp_input.c | 4 ++--
tools/include/uapi/linux/bpf.h | 2 ++
4 files changed, 8 insertions(+), 4 deletions(-)
diff --git a/include/net/tcp.h b/include/net/tcp.h
index 6ae35199d3b3c..0f75d03287c25 100644
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -2706,10 +2706,10 @@ static inline bool tcp_bpf_ca_needs_ecn(struct sock *sk)
return (tcp_call_bpf(sk, BPF_SOCK_OPS_NEEDS_ECN, 0, NULL) == 1);
}
-static inline void tcp_bpf_rtt(struct sock *sk)
+static inline void tcp_bpf_rtt(struct sock *sk, long mrtt, u32 srtt)
{
if (BPF_SOCK_OPS_TEST_FLAG(tcp_sk(sk), BPF_SOCK_OPS_RTT_CB_FLAG))
- tcp_call_bpf(sk, BPF_SOCK_OPS_RTT_CB, 0, NULL);
+ tcp_call_bpf_2arg(sk, BPF_SOCK_OPS_RTT_CB, mrtt, srtt);
}
#if IS_ENABLED(CONFIG_SMC)
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index e4ae83550fb39..d94a72593ead2 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -6947,6 +6947,8 @@ enum {
* socket transition to LISTEN state.
*/
BPF_SOCK_OPS_RTT_CB, /* Called on every RTT.
+ * Arg1: measured RTT input (mrtt)
+ * Arg2: updated srtt
*/
BPF_SOCK_OPS_PARSE_HDR_OPT_CB, /* Parse the header option.
* It will be called to handle
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 5d874817a78db..d1115d7c3936a 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -911,7 +911,7 @@ static void tcp_rtt_estimator(struct sock *sk, long mrtt_us)
tp->rtt_seq = tp->snd_nxt;
tp->mdev_max_us = tcp_rto_min_us(sk);
- tcp_bpf_rtt(sk);
+ tcp_bpf_rtt(sk, mrtt_us, srtt);
}
} else {
/* no previous measure. */
@@ -921,7 +921,7 @@ static void tcp_rtt_estimator(struct sock *sk, long mrtt_us)
tp->mdev_max_us = tp->rttvar_us;
tp->rtt_seq = tp->snd_nxt;
- tcp_bpf_rtt(sk);
+ tcp_bpf_rtt(sk, mrtt_us, srtt);
}
tp->srtt_us = max(1U, srtt);
}
diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h
index e4ae83550fb39..d94a72593ead2 100644
--- a/tools/include/uapi/linux/bpf.h
+++ b/tools/include/uapi/linux/bpf.h
@@ -6947,6 +6947,8 @@ enum {
* socket transition to LISTEN state.
*/
BPF_SOCK_OPS_RTT_CB, /* Called on every RTT.
+ * Arg1: measured RTT input (mrtt)
+ * Arg2: updated srtt
*/
BPF_SOCK_OPS_PARSE_HDR_OPT_CB, /* Parse the header option.
* It will be called to handle
--
2.32.0.3.g01195cf9f
^ permalink raw reply related [flat|nested] 4+ messages in thread* [PATCH bpf-next v1 2/2] selftests/bpf: extend BPF_SOCK_OPS_RTT_CB test for srtt and mrtt_us
2024-04-25 16:17 [PATCH bpf-next v1 0/2] bpf: add mrtt and srtt as ctx->args for BPF_SOCK_OPS_RTT_CB Philo Lu
2024-04-25 16:17 ` [PATCH bpf-next v1 1/2] bpf: add mrtt and srtt as BPF_SOCK_OPS_RTT_CB args Philo Lu
@ 2024-04-25 16:17 ` Philo Lu
2024-04-25 22:10 ` [PATCH bpf-next v1 0/2] bpf: add mrtt and srtt as ctx->args for BPF_SOCK_OPS_RTT_CB patchwork-bot+netdevbpf
2 siblings, 0 replies; 4+ messages in thread
From: Philo Lu @ 2024-04-25 16:17 UTC (permalink / raw)
To: bpf
Cc: edumazet, davem, kuba, pabeni, ast, daniel, andrii, martin.lau,
eddyz87, song, yonghong.song, john.fastabend, kpsingh, sdf,
haoluo, jolsa, dsahern, mykolal, shuah, laoar.shao, fred.cc,
xuanzhuo
Because srtt and mrtt_us are added as args in bpf_sock_ops at
BPF_SOCK_OPS_RTT_CB, a simple check is added to make sure they are both
non-zero.
$ ./test_progs -t tcp_rtt
#373 tcp_rtt:OK
Summary: 1/0 PASSED, 0 SKIPPED, 0 FAILED
Suggested-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Philo Lu <lulie@linux.alibaba.com>
---
tools/testing/selftests/bpf/prog_tests/tcp_rtt.c | 14 ++++++++++++++
tools/testing/selftests/bpf/progs/tcp_rtt.c | 6 ++++++
2 files changed, 20 insertions(+)
diff --git a/tools/testing/selftests/bpf/prog_tests/tcp_rtt.c b/tools/testing/selftests/bpf/prog_tests/tcp_rtt.c
index 8fe84da1b9b49..f2b99d95d9160 100644
--- a/tools/testing/selftests/bpf/prog_tests/tcp_rtt.c
+++ b/tools/testing/selftests/bpf/prog_tests/tcp_rtt.c
@@ -10,6 +10,9 @@ struct tcp_rtt_storage {
__u32 delivered;
__u32 delivered_ce;
__u32 icsk_retransmits;
+
+ __u32 mrtt_us; /* args[0] */
+ __u32 srtt; /* args[1] */
};
static void send_byte(int fd)
@@ -83,6 +86,17 @@ static int verify_sk(int map_fd, int client_fd, const char *msg, __u32 invoked,
err++;
}
+ /* Precise values of mrtt and srtt are unavailable, just make sure they are nonzero */
+ if (val.mrtt_us == 0) {
+ log_err("%s: unexpected bpf_tcp_sock.args[0] (mrtt_us) %u == 0", msg, val.mrtt_us);
+ err++;
+ }
+
+ if (val.srtt == 0) {
+ log_err("%s: unexpected bpf_tcp_sock.args[1] (srtt) %u == 0", msg, val.srtt);
+ err++;
+ }
+
return err;
}
diff --git a/tools/testing/selftests/bpf/progs/tcp_rtt.c b/tools/testing/selftests/bpf/progs/tcp_rtt.c
index 0988d79f15877..42c729f855246 100644
--- a/tools/testing/selftests/bpf/progs/tcp_rtt.c
+++ b/tools/testing/selftests/bpf/progs/tcp_rtt.c
@@ -10,6 +10,9 @@ struct tcp_rtt_storage {
__u32 delivered;
__u32 delivered_ce;
__u32 icsk_retransmits;
+
+ __u32 mrtt_us; /* args[0] */
+ __u32 srtt; /* args[1] */
};
struct {
@@ -55,5 +58,8 @@ int _sockops(struct bpf_sock_ops *ctx)
storage->delivered_ce = tcp_sk->delivered_ce;
storage->icsk_retransmits = tcp_sk->icsk_retransmits;
+ storage->mrtt_us = ctx->args[0];
+ storage->srtt = ctx->args[1];
+
return 1;
}
--
2.32.0.3.g01195cf9f
^ permalink raw reply related [flat|nested] 4+ messages in thread* Re: [PATCH bpf-next v1 0/2] bpf: add mrtt and srtt as ctx->args for BPF_SOCK_OPS_RTT_CB
2024-04-25 16:17 [PATCH bpf-next v1 0/2] bpf: add mrtt and srtt as ctx->args for BPF_SOCK_OPS_RTT_CB Philo Lu
2024-04-25 16:17 ` [PATCH bpf-next v1 1/2] bpf: add mrtt and srtt as BPF_SOCK_OPS_RTT_CB args Philo Lu
2024-04-25 16:17 ` [PATCH bpf-next v1 2/2] selftests/bpf: extend BPF_SOCK_OPS_RTT_CB test for srtt and mrtt_us Philo Lu
@ 2024-04-25 22:10 ` patchwork-bot+netdevbpf
2 siblings, 0 replies; 4+ messages in thread
From: patchwork-bot+netdevbpf @ 2024-04-25 22:10 UTC (permalink / raw)
To: Philo Lu
Cc: bpf, edumazet, davem, kuba, pabeni, ast, daniel, andrii,
martin.lau, eddyz87, song, yonghong.song, john.fastabend, kpsingh,
sdf, haoluo, jolsa, dsahern, mykolal, shuah, laoar.shao, fred.cc,
xuanzhuo
Hello:
This series was applied to bpf/bpf-next.git (master)
by Martin KaFai Lau <martin.lau@kernel.org>:
On Fri, 26 Apr 2024 00:17:22 +0800 you wrote:
> These provides more information about tcp RTT estimation. The selftest for
> BPF_SOCK_OPS_RTT_CB is extended for the added args.
>
> changelogs
> -> v1:
> - extend rtt selftest for added args (suggested by Stanislav)
>
> [...]
Here is the summary with links:
- [bpf-next,v1,1/2] bpf: add mrtt and srtt as BPF_SOCK_OPS_RTT_CB args
https://git.kernel.org/bpf/bpf-next/c/48e2cd3e3dcf
- [bpf-next,v1,2/2] selftests/bpf: extend BPF_SOCK_OPS_RTT_CB test for srtt and mrtt_us
https://git.kernel.org/bpf/bpf-next/c/7eb4f66b3806
You are awesome, thank you!
--
Deet-doot-dot, I am a bot.
https://korg.docs.kernel.org/patchwork/pwbot.html
^ permalink raw reply [flat|nested] 4+ messages in thread