linux/net/xfrm
Shan Wei f7c83bcbfa net: xfrm: use __this_cpu_read per-cpu helper
this_cpu_ptr/this_cpu_read is faster than per_cpu_ptr(p, smp_processor_id())
and can reduce  memory accesses.
The latter helper needs to find the offset for current cpu,
and needs more assembler instructions which objdump shows in following.

this_cpu_ptr relocates and address. this_cpu_read() relocates the address
and performs the fetch. this_cpu_read() saves you more instructions
since it can do the relocation and the fetch in one instruction.

per_cpu_ptr(p, smp_processor_id()):
  1e:   65 8b 04 25 00 00 00 00         mov    %gs:0x0,%eax
  26:   48 98                           cltq
  28:   31 f6                           xor    %esi,%esi
  2a:   48 c7 c7 00 00 00 00            mov    $0x0,%rdi
  31:   48 8b 04 c5 00 00 00 00         mov    0x0(,%rax,8),%rax
  39:   c7 44 10 04 14 00 00 00         movl   $0x14,0x4(%rax,%rdx,1)

this_cpu_ptr(p)
  1e:   65 48 03 14 25 00 00 00 00      add    %gs:0x0,%rdx
  27:   31 f6                           xor    %esi,%esi
  29:   c7 42 04 14 00 00 00            movl   $0x14,0x4(%rdx)
  30:   48 c7 c7 00 00 00 00            mov    $0x0,%rdi

Signed-off-by: Shan Wei <davidshan@tencent.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2012-11-13 14:38:52 +01:00
..
Kconfig xfrm: make xfrm_algo.c a module 2012-05-15 13:13:34 -04:00
Makefile xfrm: make xfrm_algo.c a module 2012-05-15 13:13:34 -04:00
xfrm_algo.c xfrm_algo: drop an unnecessary inclusion 2012-05-15 13:13:34 -04:00
xfrm_hash.c net: allow GFP_HIGHMEM in __vmalloc() 2010-11-21 10:04:04 -08:00
xfrm_hash.h net: cleanup unsigned to unsigned int 2012-04-15 12:44:40 -04:00
xfrm_input.c xfrm: Workaround incompatibility of ESN and async crypto 2012-09-04 14:09:45 -04:00
xfrm_ipcomp.c net: xfrm: use __this_cpu_read per-cpu helper 2012-11-13 14:38:52 +01:00
xfrm_output.c xfrm: Remove unused xfrm_state from xfrm_state_check_space 2012-03-22 19:29:58 -04:00
xfrm_policy.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2012-10-02 13:38:27 -07:00
xfrm_proc.c net: Add export.h for EXPORT_SYMBOL/THIS_MODULE to non-modules 2011-10-31 19:30:30 -04:00
xfrm_replay.c xfrm: remove redundant replay_esn check 2012-11-08 12:42:49 +01:00
xfrm_state.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2012-10-02 13:38:27 -07:00
xfrm_sysctl.c net: Convert all sysctl registrations to register_net_sysctl 2012-04-20 21:22:30 -04:00
xfrm_user.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2012-10-02 13:38:27 -07:00