diff options
| author | Brian Vazquez <brianvv@google.com> | 2023-03-01 13:32:47 +0000 |
|---|---|---|
| committer | Paolo Abeni <pabeni@redhat.com> | 2023-03-02 11:35:06 +0100 |
| commit | 5c1ebbfabcd61142a4551bfc0e51840f9bdae7af (patch) | |
| tree | b5c63584fb998ac4fce49c9abe79fa22b4e889e8 /net | |
| parent | 044c8bf78db818b8c726eb47c560e05fbc71e128 (diff) | |
| download | lwn-5c1ebbfabcd61142a4551bfc0e51840f9bdae7af.tar.gz lwn-5c1ebbfabcd61142a4551bfc0e51840f9bdae7af.zip | |
net: use indirect calls helpers for sk_exit_memory_pressure()
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>
Diffstat (limited to 'net')
| -rw-r--r-- | net/core/sock.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/net/core/sock.c b/net/core/sock.c index 341c565dbc26..c25888795390 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -2818,7 +2818,8 @@ 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; |