From: Xu Kuohai xukuohai@huawei.com
Add rb-prod test for bpf ring buffer to bench producer performance without counsumer thread. And add --rb-overwrite option to bench ring buffer in overwrite mode.
For reference, below are bench numbers collected from x86_64 and arm64 CPUs.
- AMD EPYC 9654 (x86_64)
Ringbuf, overwrite mode with multi-producer contention, no consumer =================================================================== rb-prod nr_prod 1 32.295 ± 0.004M/s (drops 0.000 ± 0.000M/s) rb-prod nr_prod 2 9.591 ± 0.003M/s (drops 0.000 ± 0.000M/s) rb-prod nr_prod 3 8.895 ± 0.002M/s (drops 0.000 ± 0.000M/s) rb-prod nr_prod 4 9.206 ± 0.003M/s (drops 0.000 ± 0.000M/s) rb-prod nr_prod 8 9.220 ± 0.002M/s (drops 0.000 ± 0.000M/s) rb-prod nr_prod 12 4.595 ± 0.022M/s (drops 0.000 ± 0.000M/s) rb-prod nr_prod 16 4.348 ± 0.016M/s (drops 0.000 ± 0.000M/s) rb-prod nr_prod 20 3.957 ± 0.017M/s (drops 0.000 ± 0.000M/s) rb-prod nr_prod 24 3.787 ± 0.014M/s (drops 0.000 ± 0.000M/s) rb-prod nr_prod 28 3.603 ± 0.011M/s (drops 0.000 ± 0.000M/s) rb-prod nr_prod 32 3.707 ± 0.011M/s (drops 0.000 ± 0.000M/s) rb-prod nr_prod 36 3.562 ± 0.012M/s (drops 0.000 ± 0.000M/s) rb-prod nr_prod 40 3.616 ± 0.012M/s (drops 0.000 ± 0.000M/s) rb-prod nr_prod 44 3.598 ± 0.016M/s (drops 0.000 ± 0.000M/s) rb-prod nr_prod 48 3.555 ± 0.014M/s (drops 0.000 ± 0.000M/s) rb-prod nr_prod 52 3.463 ± 0.020M/s (drops 0.000 ± 0.000M/s)
- HiSilicon Kunpeng 920 (arm64)
Ringbuf, overwrite mode with multi-producer contention, no consumer =================================================================== rb-prod nr_prod 1 14.687 ± 0.058M/s (drops 0.000 ± 0.000M/s) rb-prod nr_prod 2 22.263 ± 0.007M/s (drops 0.000 ± 0.000M/s) rb-prod nr_prod 3 5.736 ± 0.003M/s (drops 0.000 ± 0.000M/s) rb-prod nr_prod 4 4.934 ± 0.001M/s (drops 0.000 ± 0.000M/s) rb-prod nr_prod 8 4.661 ± 0.001M/s (drops 0.000 ± 0.000M/s) rb-prod nr_prod 12 3.753 ± 0.013M/s (drops 0.000 ± 0.000M/s) rb-prod nr_prod 16 3.706 ± 0.018M/s (drops 0.000 ± 0.000M/s) rb-prod nr_prod 20 3.660 ± 0.015M/s (drops 0.000 ± 0.000M/s) rb-prod nr_prod 24 3.610 ± 0.016M/s (drops 0.000 ± 0.000M/s) rb-prod nr_prod 28 3.238 ± 0.010M/s (drops 0.000 ± 0.000M/s) rb-prod nr_prod 32 3.270 ± 0.018M/s (drops 0.000 ± 0.000M/s) rb-prod nr_prod 36 2.892 ± 0.021M/s (drops 0.000 ± 0.000M/s) rb-prod nr_prod 40 2.995 ± 0.018M/s (drops 0.000 ± 0.000M/s) rb-prod nr_prod 44 2.830 ± 0.019M/s (drops 0.000 ± 0.000M/s) rb-prod nr_prod 48 2.877 ± 0.015M/s (drops 0.000 ± 0.000M/s) rb-prod nr_prod 52 2.814 ± 0.015M/s (drops 0.000 ± 0.000M/s)
Signed-off-by: Xu Kuohai xukuohai@huawei.com --- tools/testing/selftests/bpf/bench.c | 2 + .../selftests/bpf/benchs/bench_ringbufs.c | 95 +++++++++++++++++-- .../bpf/benchs/run_bench_ringbufs.sh | 4 + .../selftests/bpf/progs/ringbuf_bench.c | 10 ++ 4 files changed, 103 insertions(+), 8 deletions(-)
diff --git a/tools/testing/selftests/bpf/bench.c b/tools/testing/selftests/bpf/bench.c index bd29bb2e6cb5..a98063f6436a 100644 --- a/tools/testing/selftests/bpf/bench.c +++ b/tools/testing/selftests/bpf/bench.c @@ -541,6 +541,7 @@ extern const struct bench bench_trig_uretprobe_multi_nop5;
extern const struct bench bench_rb_libbpf; extern const struct bench bench_rb_custom; +extern const struct bench bench_rb_prod; extern const struct bench bench_pb_libbpf; extern const struct bench bench_pb_custom; extern const struct bench bench_bloom_lookup; @@ -617,6 +618,7 @@ static const struct bench *benchs[] = { /* ringbuf/perfbuf benchmarks */ &bench_rb_libbpf, &bench_rb_custom, + &bench_rb_prod, &bench_pb_libbpf, &bench_pb_custom, &bench_bloom_lookup, diff --git a/tools/testing/selftests/bpf/benchs/bench_ringbufs.c b/tools/testing/selftests/bpf/benchs/bench_ringbufs.c index e1ee979e6acc..6d58479fac91 100644 --- a/tools/testing/selftests/bpf/benchs/bench_ringbufs.c +++ b/tools/testing/selftests/bpf/benchs/bench_ringbufs.c @@ -19,6 +19,7 @@ static struct { int ringbuf_sz; /* per-ringbuf, in bytes */ bool ringbuf_use_output; /* use slower output API */ int perfbuf_sz; /* per-CPU size, in pages */ + bool overwrite; } args = { .back2back = false, .batch_cnt = 500, @@ -27,6 +28,7 @@ static struct { .ringbuf_sz = 512 * 1024, .ringbuf_use_output = false, .perfbuf_sz = 128, + .overwrite = false, };
enum { @@ -35,6 +37,7 @@ enum { ARG_RB_BATCH_CNT = 2002, ARG_RB_SAMPLED = 2003, ARG_RB_SAMPLE_RATE = 2004, + ARG_RB_OVERWRITE = 2005, };
static const struct argp_option opts[] = { @@ -43,6 +46,7 @@ static const struct argp_option opts[] = { { "rb-batch-cnt", ARG_RB_BATCH_CNT, "CNT", 0, "Set BPF-side record batch count"}, { "rb-sampled", ARG_RB_SAMPLED, NULL, 0, "Notification sampling"}, { "rb-sample-rate", ARG_RB_SAMPLE_RATE, "RATE", 0, "Notification sample rate"}, + { "rb-overwrite", ARG_RB_OVERWRITE, NULL, 0, "Overwrite mode"}, {}, };
@@ -72,6 +76,9 @@ static error_t parse_arg(int key, char *arg, struct argp_state *state) argp_usage(state); } break; + case ARG_RB_OVERWRITE: + args.overwrite = true; + break; default: return ARGP_ERR_UNKNOWN; } @@ -95,8 +102,30 @@ static inline void bufs_trigger_batch(void)
static void bufs_validate(void) { - if (env.consumer_cnt != 1) { - fprintf(stderr, "rb-libbpf benchmark needs one consumer!\n"); + bool bench_prod = !strcmp(env.bench_name, "rb-prod"); + + if (args.overwrite && !bench_prod) { + fprintf(stderr, "overwite mode only works with benchmakr rb-prod!\n"); + exit(1); + } + + if (bench_prod && env.consumer_cnt != 0) { + fprintf(stderr, "rb-prod benchmark does not need consumer!\n"); + exit(1); + } + + if (bench_prod && args.back2back) { + fprintf(stderr, "back-to-back mode makes no sense for rb-prod!\n"); + exit(1); + } + + if (bench_prod && args.sampled) { + fprintf(stderr, "sampling mode makes no sense for rb-prod!\n"); + exit(1); + } + + if (!bench_prod && env.consumer_cnt != 1) { + fprintf(stderr, "benchmarks excluding rb-prod need one consumer!\n"); exit(1); }
@@ -132,8 +161,10 @@ static void ringbuf_libbpf_measure(struct bench_res *res) res->drops = atomic_swap(&ctx->skel->bss->dropped, 0); }
-static struct ringbuf_bench *ringbuf_setup_skeleton(void) +static struct ringbuf_bench *ringbuf_setup_skeleton(int bench_prod) { + __u32 flags; + struct bpf_map *ringbuf; struct ringbuf_bench *skel;
setup_libbpf(); @@ -146,12 +177,19 @@ static struct ringbuf_bench *ringbuf_setup_skeleton(void)
skel->rodata->batch_cnt = args.batch_cnt; skel->rodata->use_output = args.ringbuf_use_output ? 1 : 0; + skel->rodata->bench_prod = bench_prod;
if (args.sampled) /* record data + header take 16 bytes */ skel->rodata->wakeup_data_size = args.sample_rate * 16;
- bpf_map__set_max_entries(skel->maps.ringbuf, args.ringbuf_sz); + ringbuf = skel->maps.ringbuf; + if (args.overwrite) { + flags = bpf_map__map_flags(ringbuf) | BPF_F_OVERWRITE; + bpf_map__set_map_flags(ringbuf, flags); + } + + bpf_map__set_max_entries(ringbuf, args.ringbuf_sz);
if (ringbuf_bench__load(skel)) { fprintf(stderr, "failed to load skeleton\n"); @@ -171,10 +209,13 @@ static void ringbuf_libbpf_setup(void) { struct ringbuf_libbpf_ctx *ctx = &ringbuf_libbpf_ctx; struct bpf_link *link; + int map_fd;
- ctx->skel = ringbuf_setup_skeleton(); - ctx->ringbuf = ring_buffer__new(bpf_map__fd(ctx->skel->maps.ringbuf), - buf_process_sample, NULL, NULL); + ctx->skel = ringbuf_setup_skeleton(0); + + map_fd = bpf_map__fd(ctx->skel->maps.ringbuf); + ctx->ringbuf = ring_buffer__new(map_fd, buf_process_sample, + NULL, NULL); if (!ctx->ringbuf) { fprintf(stderr, "failed to create ringbuf\n"); exit(1); @@ -232,7 +273,7 @@ static void ringbuf_custom_setup(void) void *tmp; int err;
- ctx->skel = ringbuf_setup_skeleton(); + ctx->skel = ringbuf_setup_skeleton(0);
ctx->epoll_fd = epoll_create1(EPOLL_CLOEXEC); if (ctx->epoll_fd < 0) { @@ -277,6 +318,33 @@ static void ringbuf_custom_setup(void) } }
+/* RINGBUF-PRODUCER benchmark */ +static struct ringbuf_prod_ctx { + struct ringbuf_bench *skel; +} ringbuf_prod_ctx; + +static void ringbuf_prod_measure(struct bench_res *res) +{ + struct ringbuf_prod_ctx *ctx = &ringbuf_prod_ctx; + + res->hits = atomic_swap(&ctx->skel->bss->hits, 0); + res->drops = atomic_swap(&ctx->skel->bss->dropped, 0); +} + +static void ringbuf_prod_setup(void) +{ + struct ringbuf_prod_ctx *ctx = &ringbuf_prod_ctx; + struct bpf_link *link; + + ctx->skel = ringbuf_setup_skeleton(1); + + link = bpf_program__attach(ctx->skel->progs.bench_ringbuf); + if (!link) { + fprintf(stderr, "failed to attach program!\n"); + exit(1); + } +} + #define RINGBUF_BUSY_BIT (1 << 31) #define RINGBUF_DISCARD_BIT (1 << 30) #define RINGBUF_META_LEN 8 @@ -540,6 +608,17 @@ const struct bench bench_rb_custom = { .report_final = hits_drops_report_final, };
+const struct bench bench_rb_prod = { + .name = "rb-prod", + .argp = &bench_ringbufs_argp, + .validate = bufs_validate, + .setup = ringbuf_prod_setup, + .producer_thread = bufs_sample_producer, + .measure = ringbuf_prod_measure, + .report_progress = hits_drops_report_progress, + .report_final = hits_drops_report_final, +}; + const struct bench bench_pb_libbpf = { .name = "pb-libbpf", .argp = &bench_ringbufs_argp, diff --git a/tools/testing/selftests/bpf/benchs/run_bench_ringbufs.sh b/tools/testing/selftests/bpf/benchs/run_bench_ringbufs.sh index 91e3567962ff..84ae66beb0ec 100755 --- a/tools/testing/selftests/bpf/benchs/run_bench_ringbufs.sh +++ b/tools/testing/selftests/bpf/benchs/run_bench_ringbufs.sh @@ -49,3 +49,7 @@ for b in 1 2 3 4 8 12 16 20 24 28 32 36 40 44 48 52; do summarize "rb-libbpf nr_prod $b" "$($RUN_RB_BENCH -p$b --rb-batch-cnt 50 rb-libbpf)" done
+header "Ringbuf, overwrite mode with multi-producer contention, no consumer" +for b in 1 2 3 4 8 12 16 20 24 28 32 36 40 44 48 52; do + summarize "rb-prod nr_prod $b" "$($RUN_BENCH -p$b --rb-batch-cnt 50 --rb-overwrite rb-prod)" +done diff --git a/tools/testing/selftests/bpf/progs/ringbuf_bench.c b/tools/testing/selftests/bpf/progs/ringbuf_bench.c index 6a468496f539..c55282ba4038 100644 --- a/tools/testing/selftests/bpf/progs/ringbuf_bench.c +++ b/tools/testing/selftests/bpf/progs/ringbuf_bench.c @@ -14,9 +14,11 @@ struct {
const volatile int batch_cnt = 0; const volatile long use_output = 0; +const volatile long bench_prod = 0;
long sample_val = 42; long dropped __attribute__((aligned(128))) = 0; +long hits __attribute__((aligned(128))) = 0;
const volatile long wakeup_data_size = 0;
@@ -24,6 +26,9 @@ static __always_inline long get_flags() { long sz;
+ if (bench_prod) + return BPF_RB_NO_WAKEUP; + if (!wakeup_data_size) return 0;
@@ -47,6 +52,8 @@ int bench_ringbuf(void *ctx) *sample = sample_val; flags = get_flags(); bpf_ringbuf_submit(sample, flags); + if (bench_prod) + __sync_add_and_fetch(&hits, 1); } } } else { @@ -55,6 +62,9 @@ int bench_ringbuf(void *ctx) if (bpf_ringbuf_output(&ringbuf, &sample_val, sizeof(sample_val), flags)) __sync_add_and_fetch(&dropped, 1); + else if (bench_prod) + __sync_add_and_fetch(&hits, 1); + } } return 0;