The purpose of this patch-set is to eliminate more redundant
payload-dependencies.
Here's the netlink dump for a test where such a dependency is not
eliminated.
[ meta load nfproto => reg 1 ]
[ cmp eq reg 1 0x00000002 ]
[ meta load l4proto => reg 1 ]
[ cmp eq reg 1 0x00000006 ]
[ payload load 4b @ network header + 12 => reg 1 ]
[ payload load 4b @ network header + 16 => reg 9 ]
[ payload load 2b @ transport header + 2 => reg 10 ]
[ lookup reg 1 set set3 ]
[ immediate reg 0 accept ]
The reason the `meta nfproto` match is not eliminated is that it is
overwritten in the dependency context by the `meta l4proto` match before
we get to the `ip saddr` and `ip daddr` expressions which would have
caused it to be eliminated. By contrast, the `meta l4proto` match _is_
eliminated because it is still present in the context we get to the `tcp
dport` expression. Therefore, this patch-set extends the payload-
dependency context to store not just a single dependency, but one per
protocol layer.
Patch 1 fixes a mistake in a Python test-case. Patch 2 makes some
preliminary changes. Patch 3 adds the extra dependencies. Patches 4 &
5 remove redundant protocol matches which are now eliminated from
test-cases.
At the end of this series all tests pass.
Changes since v1.
* The first seven v1 patches have been merged. The remaining four
form patches 2-5 in this series.
* Patch 1 is new: it fixes a test-case that was supposed to be fixed
by patch 2 in v1.
* The helper added by patch 2 has been changed to return the
expression from the payload dependency statement, not the statement
itself. The removal of the redundant `ctx->pbase` check is new.
Jeremy Sowden (5):
tests: py: fix inet/ip.t bridge payload
src: add a helper that returns a payload dependency for a particular
base
src: store more than one payload dependency
tests: py: remove redundant payload expressions
tests: shell: remove redundant payload expressions
include/payload.h | 15 ++--
src/netlink_delinearize.c | 18 +++--
src/payload.c | 72 ++++++++++++++-----
tests/py/inet/icmpX.t | 2 +-
tests/py/inet/icmpX.t.json.output | 9 ---
tests/py/inet/ip.t.payload.bridge | 2 +-
tests/py/inet/sets.t.json | 11 ---
.../testcases/maps/dumps/0010concat_map_0.nft | 2 +-
.../testcases/maps/dumps/nat_addr_port.nft | 8 +--
9 files changed, 79 insertions(+), 60 deletions(-)
--
2.34.1
