diff options
| author | Wei Wang <weiwan@google.com> | 2021-02-02 11:34:08 -0800 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2021-02-03 18:43:17 -0800 |
| commit | f5a5589c72509abaeb705123b64e7f5a078becf0 (patch) | |
| tree | 93de7e2e315b70f7d34a60b7b5b6cc0f56f8be1b | |
| parent | 6fd5eeee1f107e2fb805609779994e3526de184f (diff) | |
| download | linux-next-f5a5589c72509abaeb705123b64e7f5a078becf0.tar.gz | |
tcp: use a smaller percpu_counter batch size for sk_alloc
Currently, a percpu_counter with the default batch size (2*nr_cpus) is
used to record the total # of active sockets per protocol. This means
sk_sockets_allocated_read_positive() could be off by +/-2*(nr_cpus^2).
This under/over-estimation could lead to wrong memory suppression
conditions in __sk_raise_mem_allocated().
Fix this by using a more reasonable fixed batch size of 16.
See related commit cf86a086a180 ("net/dst: use a smaller percpu_counter
batch for dst entries accounting") that addresses a similar issue.
Signed-off-by: Wei Wang <weiwan@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Soheil Hassas Yeganeh <soheil@google.com>
Link: https://lore.kernel.org/r/20210202193408.1171634-1-weiwan@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
| -rw-r--r-- | include/net/sock.h | 8 |
1 files changed, 6 insertions, 2 deletions
diff --git a/include/net/sock.h b/include/net/sock.h index 129d200bccb4..690e496a0e79 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -1350,14 +1350,18 @@ sk_memory_allocated_sub(struct sock *sk, int amt) atomic_long_sub(amt, sk->sk_prot->memory_allocated); } +#define SK_ALLOC_PERCPU_COUNTER_BATCH 16 + static inline void sk_sockets_allocated_dec(struct sock *sk) { - percpu_counter_dec(sk->sk_prot->sockets_allocated); + percpu_counter_add_batch(sk->sk_prot->sockets_allocated, -1, + SK_ALLOC_PERCPU_COUNTER_BATCH); } static inline void sk_sockets_allocated_inc(struct sock *sk) { - percpu_counter_inc(sk->sk_prot->sockets_allocated); + percpu_counter_add_batch(sk->sk_prot->sockets_allocated, 1, + SK_ALLOC_PERCPU_COUNTER_BATCH); } static inline u64 |