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  1. 31 8月, 2017 1 次提交
  3. 14 4月, 2017 1 次提交
  5. 18 11月, 2016 1 次提交
    • A
      netns: make struct pernet_operations::id unsigned int · c7d03a00
      由 Alexey Dobriyan 提交于 
      Make struct pernet_operations::id unsigned.

There are 2 reasons to do so:

1)
This field is really an index into an zero based array and
thus is unsigned entity. Using negative value is out-of-bound
access by definition.

2)
On x86_64 unsigned 32-bit data which are mixed with pointers
via array indexing or offsets added or subtracted to pointers
are preffered to signed 32-bit data.

"int" being used as an array index needs to be sign-extended
to 64-bit before being used.

	void f(long *p, int i)
	{
		g(p[i]);
	}

  roughly translates to

	movsx	rsi, esi
	mov	rdi, [rsi+...]
	call 	g

MOVSX is 3 byte instruction which isn't necessary if the variable is
unsigned because x86_64 is zero extending by default.

Now, there is net_generic() function which, you guessed it right, uses
"int" as an array index:

	static inline void *net_generic(const struct net *net, int id)
	{
		...
		ptr = ng->ptr[id - 1];
		...
	}

And this function is used a lot, so those sign extensions add up.

Patch snipes ~1730 bytes on allyesconfig kernel (without all junk
messing with code generation):

	add/remove: 0/0 grow/shrink: 70/598 up/down: 396/-2126 (-1730)

Unfortunately some functions actually grow bigger.
This is a semmingly random artefact of code generation with register
allocator being used differently. gcc decides that some variable
needs to live in new r8+ registers and every access now requires REX
prefix. Or it is shifted into r12, so [r12+0] addressing mode has to be
used which is longer than [r8]

However, overall balance is in negative direction:

	add/remove: 0/0 grow/shrink: 70/598 up/down: 396/-2126 (-1730)
	function                                     old     new   delta
	nfsd4_lock                                  3886    3959     +73
	tipc_link_build_proto_msg                   1096    1140     +44
	mac80211_hwsim_new_radio                    2776    2808     +32
	tipc_mon_rcv                                1032    1058     +26
	svcauth_gss_legacy_init                     1413    1429     +16
	tipc_bcbase_select_primary                   379     392     +13
	nfsd4_exchange_id                           1247    1260     +13
	nfsd4_setclientid_confirm                    782     793     +11
		...
	put_client_renew_locked                      494     480     -14
	ip_set_sockfn_get                            730     716     -14
	geneve_sock_add                              829     813     -16
	nfsd4_sequence_done                          721     703     -18
	nlmclnt_lookup_host                          708     686     -22
	nfsd4_lockt                                 1085    1063     -22
	nfs_get_client                              1077    1050     -27
	tcf_bpf_init                                1106    1076     -30
	nfsd4_encode_fattr                          5997    5930     -67
	Total: Before=154856051, After=154854321, chg -0.00%
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      c7d03a00
  7. 28 10月, 2016 1 次提交
  9. 26 7月, 2016 1 次提交
    • W
      net_sched: move tc_action into tcf_common · a85a970a
      由 WANG Cong 提交于 
      struct tc_action is confusing, currently we use it for two purposes:
1) Pass in arguments and carry out results from helper functions
2) A generic representation for tc actions

The first one is error-prone, since we need to make sure we don't
miss anything. This patch aims to get rid of this use, by moving
tc_action into tcf_common, so that they are allocated together
in hashtable and can be cast'ed easily.

And together with the following patch, we could really make
tc_action a generic representation for all tc actions and each
type of action can inherit from it.

Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      a85a970a
  11. 05 7月, 2016 2 次提交
  13. 16 6月, 2016 1 次提交
  15. 08 6月, 2016 3 次提交
  17. 11 5月, 2016 1 次提交
  19. 27 4月, 2016 1 次提交
  21. 26 2月, 2016 1 次提交
  23. 09 7月, 2015 1 次提交
  25. 13 2月, 2014 3 次提交
  27. 22 1月, 2014 1 次提交
  29. 20 1月, 2014 1 次提交
  31. 14 1月, 2014 1 次提交
  33. 28 12月, 2013 1 次提交
    • J
      net_sched: act: Dont increment refcnt on replace · 1a29321e
      由 Jamal Hadi Salim 提交于 
       This is a bug fix. The existing code tries to kill many
 birds with one stone: Handling binding of actions to
 filters, new actions and replacing of action
 attributes. A simple test case to illustrate:

XXXX
 moja@fe1:~$ sudo tc actions add action drop index 12
 moja@fe1:~$ actions get action gact index 12
 action order 1: gact action drop
  random type none pass val 0
  index 12 ref 1 bind 0
 moja@fe1:~$ sudo tc actions replace action ok index 12
 moja@fe1:~$ actions get action gact index 12
 action order 1: gact action drop
  random type none pass val 0
  index 12 ref 2 bind 0
XXXX

The above shows the refcounf being wrongly incremented on replace.
There are more complex scenarios with binding of actions to filters
that i am leaving out that didnt work as well...
Signed-off-by: NJamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      1a29321e
  35. 21 12月, 2013 1 次提交
  37. 19 12月, 2013 1 次提交
  39. 07 12月, 2013 1 次提交
  41. 06 12月, 2013 1 次提交
  43. 15 1月, 2013 1 次提交
  45. 02 4月, 2012 1 次提交
  47. 06 7月, 2011 1 次提交
  49. 20 1月, 2011 1 次提交
  51. 11 1月, 2011 1 次提交
  53. 18 8月, 2010 1 次提交
  55. 23 10月, 2009 1 次提交
  57. 26 11月, 2008 1 次提交
  59. 13 9月, 2008 1 次提交