On 04/07/17 20:22, Edward Cree wrote:

I don't know why test_l4lb has to process _fewer_ insns with my patches;
 if anything I'm worrying that I may be incorrectly pruning branches.
(I've spotted a possible bug in that I'm not looking at 'id' which,
 although it doesn't have to match, if two regs in the old state had the
 same id as each other, then those regs in the new state have to have
 the same id as each other too.)

I've now fixed that bug, and also changing it to not fill in 'id' on pointers
 other than PTR_TO_PACKET when doing arithmetic (because it's only used for
 'range' sharing and only PTR_TO_PACKET have that.  Of course
 PTR_TO_MAP_VALUE_OR_NULL still use id, but they don't get it from arithmetic).
Changes will be in next version of patch series, but for now:
Program         net-next  short  full   new
test_pkt_access       78     79    79    79
test_xdp             386    411   407   389
test_l4lb           6438   4154  4154  4062
test_tcp_estats      435    436   435   435
test_bpf_obj_id        8      8     8     8
test_pkt_md_access    41     42    42    42
As you can see, the #insns has gone down even further.

-Ed