From: Brian Vazquez brianvv@google.com
[ Upstream commit 5c1ebbfabcd61142a4551bfc0e51840f9bdae7af ]
Florian reported a regression and sent a patch with the following changelog:
<quote> There is a noticeable tcp performance regression (loopback or cross-netns), seen with iperf3 -Z (sendfile mode) when generic retpolines are needed.
With SK_RECLAIM_THRESHOLD checks gone number of calls to enter/leave memory pressure happen much more often. For TCP indirect calls are used.
We can't remove the if-set-return short-circuit check in tcp_enter_memory_pressure because there are callers other than sk_enter_memory_pressure. Doing a check in the sk wrapper too reduces the indirect calls enough to recover some performance.
Before, 0.00-60.00 sec 322 GBytes 46.1 Gbits/sec receiver
After: 0.00-60.04 sec 359 GBytes 51.4 Gbits/sec receiver
"iperf3 -c $peer -t 60 -Z -f g", connected via veth in another netns. </quote>
It seems we forgot to upstream this indirect call mitigation we had for years, lets do this instead.
[edumazet] - It seems we forgot to upstream this indirect call mitigation we had for years, let's do this instead. - Changed to INDIRECT_CALL_INET_1() to avoid bots reports.
Fixes: 4890b686f408 ("net: keep sk->sk_forward_alloc as small as possible") Reported-by: Florian Westphal fw@strlen.de Link: https://lore.kernel.org/netdev/20230227152741.4a53634b@kernel.org/T/ Signed-off-by: Brian Vazquez brianvv@google.com Signed-off-by: Eric Dumazet edumazet@google.com Link: https://lore.kernel.org/r/20230301133247.2346111-1-edumazet@google.com Signed-off-by: Paolo Abeni pabeni@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- net/core/sock.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/net/core/sock.c b/net/core/sock.c index 4dfdcdfd00114..eb0b76acd9df1 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -2805,7 +2805,8 @@ static void sk_enter_memory_pressure(struct sock *sk) static void sk_leave_memory_pressure(struct sock *sk) { if (sk->sk_prot->leave_memory_pressure) { - sk->sk_prot->leave_memory_pressure(sk); + INDIRECT_CALL_INET_1(sk->sk_prot->leave_memory_pressure, + tcp_leave_memory_pressure, sk); } else { unsigned long *memory_pressure = sk->sk_prot->memory_pressure;