net: increase skb_defer_max default to 128

skb_defer_max value is very conservative, and can be increased
to avoid too many calls to kick_defer_list_purge().

Signed-off-by: Eric Dumazet <[email protected]>
Reviewed-by: Kuniyuki Iwashima <[email protected]>
Reviewed-by: Toke Høiland-Jørgensen <[email protected]>
Reviewed-by: Jason Xing <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>

Documentation/admin-guide/sysctl/net.rst

@@ -355,9 +355,9 @@ skb_defer_max
 -------------
 
 Max size (in skbs) of the per-cpu list of skbs being freed
-by the cpu which allocated them. Used by TCP stack so far.
+by the cpu which allocated them.
 
-Default: 64
+Default: 128
 
 optmem_max
 ----------

net/core/hotdata.c

@@ -20,7 +20,7 @@ struct net_hotdata net_hotdata __cacheline_aligned = {
 	.dev_tx_weight = 64,
 	.dev_rx_weight = 64,
 	.sysctl_max_skb_frags = MAX_SKB_FRAGS,
-	.sysctl_skb_defer_max = 64,
+	.sysctl_skb_defer_max = 128,
 	.sysctl_mem_pcpu_rsv = SK_MEMORY_PCPU_RESERVE
 };
 EXPORT_SYMBOL(net_hotdata);