From: Alexei Starovoitov Date: Wed, 17 May 2023 05:31:52 +0000 (-0700) Subject: Merge branch 'seltests/xsk: prepare for AF_XDP multi-buffer testing' X-Git-Tag: v6.6.7~2536^2~215^2~22 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=34e78bab67c5de43e685c63cd8c27e0cd3239897;p=platform%2Fkernel%2Flinux-starfive.git Merge branch 'seltests/xsk: prepare for AF_XDP multi-buffer testing' Magnus Karlsson says: ==================== Prepare the AF_XDP selftests test framework code for the upcoming multi-buffer support in AF_XDP. This so that the multi-buffer patch set does not become way too large. In that upcoming patch set, we are only including the multi-buffer tests together with any framework code that depends on the new options bit introduced in the AF_XDP multi-buffer implementation itself. Currently, the test framework is based on the premise that a packet consists of a single fragment and thus occupies a single buffer and a single descriptor. Multi-buffer breaks this assumption, as that is the whole purpose of it. Now, a packet can consist of multiple buffers and therefore consume multiple descriptors. The patch set starts with some clean-ups and simplifications followed by patches that make sure that the current code works even when a packet occupies multiple buffers. The actual code for sending and receiving multi-buffer packets will be included in the AF_XDP multi-buffer patch set as it depends on a new bit being used in the options field of the descriptor. Patch set anatomy: 1: The XDP program was unnecessarily changed many times. Fixes this. 2: There is no reason to generate a full UDP/IPv4 packet as it is never used. Simplify the code by just generating a valid Ethernet frame. 3: Introduce a more complicated payload pattern that can detect fragments out of bounds in a multi-buffer packet and other errors found in single-fragment packets. 4: As a convenience, dump the content of the faulty packet at error. 5: To simplify the code, make the usage of the packet stream for Tx and Rx more similar. 6: Store the offset of the packet in the buffer in the struct pkt definition instead of the address in the umem itself and introduce a simple buffer allocator. The address only made sense when all packets consumed a single buffer. Now, we do not know beforehand how many buffers a packet will consume, so we instead just allocate a buffer from the allocator and specify the offset within that buffer. 7: Test for huge pages only once instead of before each test that needs it. 8: Populate the fill ring based on how many frags are needed for each packet. 9: Change the data generation code so it can generate data for multi-buffer packets too. 10: Adjust the packet pacing algorithm so that it can cope with multi-buffer packets. The pacing algorithm is present so that Tx does not send too many packets/frames to Rx that it starts to drop packets. That would ruin the tests. v1 -> v2: * Fixed spelling error in patch #6 [Simon] * Fixed compilation error with llvm in patch #7 [Daniel] Thanks: Magnus ==================== Signed-off-by: Alexei Starovoitov --- 34e78bab67c5de43e685c63cd8c27e0cd3239897