Subject: Re: [PATCH stable 4.9 00/29] backport of IP fragmentation fixes

From: Eric Dumazet <[email-masked]>
Date: Tue, 9 Oct 2018 17:46:30 -0700

On 10/09/2018 03:48 PM, Florian Fainelli wrote:
> This is based on Stephen's v4.14 patches, with the necessary merge
> conflicts, and the lack of timer_setup() on the 4.9 baseline.
> 
> Perf results on a gigabit capable system, before and after are below.
> 
> Series can also be found here:
> 
> https://github.com/ffainelli/linux/commits/fragment-stack-v4.9
> 
> 
>    PerfTop:     457 irqs/sec  kernel:74.4%  exact:  0.0% [4000Hz cycles],  (all, 4 CPUs)
> -------------------------------------------------------------------------------
> 
>     29.62%  [kernel]       [k] ip_defrag                  
>      6.57%  [kernel]       [k] arch_cpu_idle              
>      1.72%  [kernel]       [k] v7_dma_inv_range           
>      1.68%  [kernel]       [k] __netif_receive_skb_core   
>      1.43%  [kernel]       [k] fib_table_lookup           
>      1.30%  [kernel]       [k] finish_task_switch         
>      1.08%  [kernel]       [k] ip_rcv                     
>      1.01%  [kernel]       [k] skb_release_data           
>      0.99%  [kernel]       [k] __slab_free                
>      0.96%  [kernel]       [k] bcm_sysport_poll           
>      0.88%  [kernel]       [k] __netdev_alloc_skb         
>      0.87%  [kernel]       [k] tick_nohz_idle_enter       
>      0.86%  [kernel]       [k] dev_gro_receive            
>      0.85%  [kernel]       [k] _raw_spin_unlock_irqrestore
>      0.84%  [kernel]       [k] __memzero                  
>      0.74%  [kernel]       [k] tick_nohz_idle_exit        
>      0.73%  ld-2.24.so     [.] do_lookup_x                
>      0.66%  [kernel]       [k] kmem_cache_free            
>      0.66%  [kernel]       [k] bcm_sysport_rx_refill      
>      0.65%  [kernel]       [k] eth_type_trans             
> 
> 
> After patching:
> 
>   PerfTop:     170 irqs/sec  kernel:86.5%  exact:  0.0% [4000Hz cycles],  (all, 4 CPUs)
> -------------------------------------------------------------------------------
> 
>      7.79%  [kernel]       [k] arch_cpu_idle              
>      5.14%  [kernel]       [k] v7_dma_inv_range           
>      4.20%  [kernel]       [k] ip_defrag                  
>      3.89%  [kernel]       [k] __netif_receive_skb_core   
>      3.65%  [kernel]       [k] fib_table_lookup           
>      2.16%  [kernel]       [k] finish_task_switch         
>      1.93%  [kernel]       [k] _raw_spin_unlock_irqrestore
>      1.90%  [kernel]       [k] ip_rcv                     
>      1.84%  [kernel]       [k] bcm_sysport_poll           
>      1.83%  [kernel]       [k] __memzero                  
>      1.65%  [kernel]       [k] __netdev_alloc_skb         
>      1.60%  [kernel]       [k] __slab_free                
>      1.49%  [kernel]       [k] __do_softirq               
>      1.49%  [kernel]       [k] bcm_sysport_rx_refill      
>      1.31%  [kernel]       [k] dma_cache_maint_page       
>      1.25%  [kernel]       [k] tick_nohz_idle_enter       
>      1.24%  [kernel]       [k] ip_route_input_noref       
>      1.17%  [kernel]       [k] eth_type_trans             
>      1.06%  [kernel]       [k] fib_validate_source        
>      1.03%  [kernel]       [k] inet_frag_find    
> 
> Dan Carpenter (1):
>   ipv4: frags: precedence bug in ip_expire()
> 
> Eric Dumazet (22):
>   inet: frags: change inet_frags_init_net() return value
>   inet: frags: add a pointer to struct netns_frags
>   inet: frags: refactor ipfrag_init()
>   inet: frags: refactor ipv6_frag_init()
>   inet: frags: refactor lowpan_net_frag_init()
>   ipv6: export ip6 fragments sysctl to unprivileged users
>   rhashtable: add schedule points
>   inet: frags: use rhashtables for reassembly units
>   inet: frags: remove some helpers
>   inet: frags: get rif of inet_frag_evicting()
>   inet: frags: remove inet_frag_maybe_warn_overflow()
>   inet: frags: break the 2GB limit for frags storage
>   inet: frags: do not clone skb in ip_expire()
>   ipv6: frags: rewrite ip6_expire_frag_queue()
>   rhashtable: reorganize struct rhashtable layout
>   inet: frags: reorganize struct netns_frags
>   inet: frags: get rid of ipfrag_skb_cb/FRAG_CB
>   inet: frags: fix ip6frag_low_thresh boundary
>   net: speed up skb_rbtree_purge()
>   net: pskb_trim_rcsum() and CHECKSUM_COMPLETE are friends
>   net: add rb_to_skb() and other rb tree helpers
>   net: sk_buff rbnode reorg
> 
> Florian Westphal (1):
>   ipv6: defrag: drop non-last frags smaller than min mtu
> 
> Peter Oskolkov (4):
>   ip: discard IPv4 datagrams with overlapping segments.
>   net: modify skb_rbtree_purge to return the truesize of all purged
>     skbs.
>   ip: add helpers to process in-order fragments faster.
>   ip: process in-order fragments efficiently
> 
> Taehee Yoo (1):
>   ip: frags: fix crash in ip_do_fragment()
>

Strange, I do not see "ip: use rb trees for IP frag queue." in this list ?

Thanks !