diff options
| author | Eric Dumazet <edumazet@google.com> | 2024-02-27 21:01:04 +0000 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2024-02-28 20:22:03 -0800 |
| commit | 1200097fa8f0d8e8ddfe5c554d8fa2bc03b2df92 (patch) | |
| tree | ac87c697e3641810532af04a5dc19cfb15cec2bc /net | |
| parent | 99123622050f10ca9148a0fffba2de0afd6cdfff (diff) | |
net: call skb_defer_free_flush() from __napi_busy_loop()
skb_defer_free_flush() is currently called from net_rx_action()
and napi_threaded_poll().
We should also call it from __napi_busy_loop() otherwise
there is the risk the percpu queue can grow until an IPI
is forced from skb_attempt_defer_free() adding a latency spike.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Samiullah Khawaja <skhawaja@google.com>
Acked-by: Stanislav Fomichev <sdf@google.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Link: https://lore.kernel.org/r/20240227210105.3815474-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'net')
| -rw-r--r-- | net/core/dev.c | 43 |
1 files changed, 22 insertions, 21 deletions
diff --git a/net/core/dev.c b/net/core/dev.c index 275fd5259a4a..053fac78305c 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -6173,6 +6173,27 @@ struct napi_struct *napi_by_id(unsigned int napi_id) return NULL; } +static void skb_defer_free_flush(struct softnet_data *sd) +{ + struct sk_buff *skb, *next; + + /* Paired with WRITE_ONCE() in skb_attempt_defer_free() */ + if (!READ_ONCE(sd->defer_list)) + return; + + spin_lock(&sd->defer_lock); + skb = sd->defer_list; + sd->defer_list = NULL; + sd->defer_count = 0; + spin_unlock(&sd->defer_lock); + + while (skb != NULL) { + next = skb->next; + napi_consume_skb(skb, 1); + skb = next; + } +} + #if defined(CONFIG_NET_RX_BUSY_POLL) static void __busy_poll_stop(struct napi_struct *napi, bool skip_schedule) @@ -6297,6 +6318,7 @@ count: if (work > 0) __NET_ADD_STATS(dev_net(napi->dev), LINUX_MIB_BUSYPOLLRXPACKETS, work); + skb_defer_free_flush(this_cpu_ptr(&softnet_data)); local_bh_enable(); if (!loop_end || loop_end(loop_end_arg, start_time)) @@ -6726,27 +6748,6 @@ static int napi_thread_wait(struct napi_struct *napi) return -1; } -static void skb_defer_free_flush(struct softnet_data *sd) -{ - struct sk_buff *skb, *next; - - /* Paired with WRITE_ONCE() in skb_attempt_defer_free() */ - if (!READ_ONCE(sd->defer_list)) - return; - - spin_lock(&sd->defer_lock); - skb = sd->defer_list; - sd->defer_list = NULL; - sd->defer_count = 0; - spin_unlock(&sd->defer_lock); - - while (skb != NULL) { - next = skb->next; - napi_consume_skb(skb, 1); - skb = next; - } -} - static int napi_threaded_poll(void *data) { struct napi_struct *napi = data; |