Difference between revisions of "VPP/AArch64"

Revision as of 15:58, 6 November 2017

Recent Patches

make test

Test order

Some tests are not meant to be played alone.

For example the test_l2bd_arp_term_\d+ list

• test_1: create 5 hosts
• test_2: delete 3 of the hosts created by test_1

...

Those tests should be played grouped. For example in the case above ;

# works
make test TEST=*.TestL2bdArpTerm.*
# does not work
make test V=1 TEST=*.TestL2bdArpTerm.test_l2bd_arp_term_01
make test V=1 TEST=*.TestL2bdArpTerm.test_l2bd_arp_term_02
...

Test timeout durations

Some tests might need timer finetuning: Example test_cflow_packet:

assertAlmostEqual(cflow[IPFIX].exportTime, nowUTC, delta=5)

random test failure

Workaround: disable aslr

sysctl -w kernel.randomize_va_space=0

Test status

make test-debug status OK

make test-all-debug

status: some tests timeout

Example:

"Starting create 100k of p2p subifs ..."

make test status: OK

make test-all status: some tests timeout

make pkg-deb & make pkg-rpm

pkg-rpm

test OK on Fedora 26 (Server Edition)

pkg-deb

pkg-rpm test OK on Ubuntu 16.04.3 LTS

CSIT func & perf

TODO

AArch64 Porting & Tuning

Support multiple cache line sizes per architecture. AArch64 is currently hard coded to 128B. For native build, inspect ARMv8 Main ID Register in Makefile and pass cache line size as compiler option, e.g. -DCACHE_LINE_SIZE=128.

Investigate "show cpu" output and Arm CPU feature detection (AES, SHA1, SHA2, CRC32, ATOMICS) via hwcaps. src/vppinfra/cpu.[ch]

Review use of Arm architected timer in src/vppinfra/time.[ch]

Use ISB or YIELD in src/vppinfra/smp.h

Use REV in src/vppinfra/byte_order.h

Review use of __sync_xxx/__atomic_xxx builtins to ensure correct memory ordering on non-TSO machines.

Investigate hash performance (CRC32 vs xxhash) e.g. in src/vppinfra/bihash_8_8.h. Dependent on Arm CPU feature detection.

Investigate memcpy performance (src/vppinfra/string.h); both inlined-by-compiler and libc versions.

Investigate dual/quad loop tuning, e.g. l2_forward().

SIMD

• CLIB_HAVE_VEC128 also covers 256-bit. Add CLIB_HAVE_VEC256?
• ixge.[ch] - 128-bit vector types with plain C. Needs to be enabled.
• mheap.c - requires NEON implementation of is_equal
• hash.h - requires NEON implementation of irotate
• vnet_classify.h - 128-bit vector types with plain C. Needs to be enabled.
• vhost-user.c - SSE4.2 only. Implement range search using NEON.
• ip4_mtrie.h - 128-bit vector types with plain C. Needs to be enabled.

Known Issues

GCC 5.3.x ICEs during FP register allocation. Please use GCC 5.4+.

Arch Linux ARM is missing a few dependencies.

IRC Channel

#fdio-arm on freenode.net

Meeting Minutes

Date & Time (weekly): http://bit.ly/2yIzHYv

Meeting: https://meet.lync.com/armh/brian.brooks/NQB2H7R6

10/25/2017

• Gabriel working on vpp init failure in linux_pci_init()
• Kumar to check with GeorgeZ on Huawei boards shipped to CSIT; need to verify tests also on this environment (package versions from distro)
• Brian to check whether anything else needs to be done besides 'make test' for upstream enablement