Eric Dumazet 73f156a6e8 inetpeer: get rid of ip_id_count ... Ideally, we would need to generate IP ID using a per destination IP generator. linux kernels used inet_peer cache for this purpose, but this had a huge cost on servers disabling MTU discovery. 1) each inet_peer struct consumes 192 bytes 2) inetpeer cache uses a binary tree of inet_peer structs, with a nominal size of ~66000 elements under load. 3) lookups in this tree are hitting a lot of cache lines, as tree depth is about 20. 4) If server deals with many tcp flows, we have a high probability of not finding the inet_peer, allocating a fresh one, inserting it in the tree with same initial ip_id_count, (cf secure_ip_id()) 5) We garbage collect inet_peer aggressively. IP ID generation do not have to be 'perfect' Goal is trying to avoid duplicates in a short period of time, so that reassembly units have a chance to complete reassembly of fragments belonging to one message before receiving other fragments with a recycled ID. We simply use an array of generators, and a Jenkin hash using the dst IP as a key. ipv6_select_ident() is put back into net/ipv6/ip6_output.c where it belongs (it is only used from this file) secure_ip_id() and secure_ipv6_id() no longer are needed. Rename ip_select_ident_more() to ip_select_ident_segs() to avoid unnecessary decrement/increment of the number of segments. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>		2014-06-02 11:00:41 -07:00
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bsd_comp.c
Kconfig
Makefile
ppp_async.c
ppp_deflate.c
ppp_generic.c	net: filter: let unattached filters use sock_fprog_kern	2014-05-23 16:48:05 -04:00
ppp_mppe.c	drivers/net/*: Fix FSF address in file headers	2013-12-06 12:37:55 -05:00
ppp_mppe.h
ppp_synctty.c
pppoe.c	ppp: slight optimization of addr compare	2013-12-26 13:31:33 -05:00
pppox.c
pptp.c	inetpeer: get rid of ip_id_count	2014-06-02 11:00:41 -07:00