From: Puranjay Mohan Date: Wed, 20 May 2026 13:33:31 +0000 (-0700) Subject: selftests/bpf: Fix expired UDP LRU entries in XDP LB benchmark X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=12e896b9794bbd88f56aeac2a5807ae8d4bb5ad8;p=thirdparty%2Fkernel%2Flinux.git selftests/bpf: Fix expired UDP LRU entries in XDP LB benchmark populate_lru() zero-initializes atime: struct real_pos_lru lru = { .pos = real_idx }; connection_table_lookup() treats UDP entries with cur_time - atime > 30s as expired, so every pre-populated entry expires immediately. Calibration masks this on the CPU it runs on, but if validation migrates to another CPU: [udp-v4-lru-hit] COUNTER FAIL: LRU misses=1, expected 0 Initialize atime from CLOCK_MONOTONIC for UDP flows. Fixes: a4b5ba8187cb ("selftests/bpf: Add XDP load-balancer benchmark driver") Signed-off-by: Puranjay Mohan Link: https://lore.kernel.org/r/20260520133338.3392667-3-puranjay@kernel.org Signed-off-by: Alexei Starovoitov --- diff --git a/tools/testing/selftests/bpf/benchs/bench_xdp_lb.c b/tools/testing/selftests/bpf/benchs/bench_xdp_lb.c index 0b6709a2b03c6..8e25bccbde92b 100644 --- a/tools/testing/selftests/bpf/benchs/bench_xdp_lb.c +++ b/tools/testing/selftests/bpf/benchs/bench_xdp_lb.c @@ -563,12 +563,23 @@ static void create_per_cpu_lru_maps(struct xdp_lb_bench *skel) nr_inner_maps = nr_cpus; } +static __u64 ktime_get_ns(void) +{ + struct timespec ts; + + clock_gettime(CLOCK_MONOTONIC, &ts); + return (__u64)ts.tv_sec * 1000000000ULL + ts.tv_nsec; +} + static void populate_lru(const struct test_scenario *sc, __u32 real_idx) { struct real_pos_lru lru = { .pos = real_idx }; struct flow_key fk; int i, err; + if (sc->ip_proto == IPPROTO_UDP) + lru.atime = ktime_get_ns(); + build_flow_key(&fk, sc); /* Insert into every per-CPU inner LRU so the entry is found