From c6497df0ddc3363c2c940d92c3af0b2620477003 Mon Sep 17 00:00:00 2001 From: "Daniel T. Lee" Date: Tue, 24 Nov 2020 09:03:08 +0000 Subject: [PATCH] samples: bpf: Refactor test_overhead program with libbpf This commit refactors the existing program with libbpf bpf loader. Since the kprobe, tracepoint and raw_tracepoint bpf program can be attached with single bpf_program__attach() interface, so the corresponding function of libbpf is used here. Rather than specifying the number of cpus inside the code, this commit uses the number of available cpus with _SC_NPROCESSORS_ONLN. Signed-off-by: Daniel T. Lee Signed-off-by: Andrii Nakryiko Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20201124090310.24374-6-danieltimlee@gmail.com --- samples/bpf/Makefile | 2 +- samples/bpf/test_overhead_user.c | 82 +++++++++++++++++++++++--------- 2 files changed, 60 insertions(+), 24 deletions(-) diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile index 09a249477554..25380e04897e 100644 --- a/samples/bpf/Makefile +++ b/samples/bpf/Makefile @@ -78,7 +78,7 @@ lathist-objs := lathist_user.o offwaketime-objs := offwaketime_user.o $(TRACE_HELPERS) spintest-objs := spintest_user.o $(TRACE_HELPERS) map_perf_test-objs := map_perf_test_user.o -test_overhead-objs := bpf_load.o test_overhead_user.o +test_overhead-objs := test_overhead_user.o test_cgrp2_array_pin-objs := test_cgrp2_array_pin.o test_cgrp2_attach-objs := test_cgrp2_attach.o test_cgrp2_sock-objs := test_cgrp2_sock.o diff --git a/samples/bpf/test_overhead_user.c b/samples/bpf/test_overhead_user.c index 94f74112a20e..819a6fe86f89 100644 --- a/samples/bpf/test_overhead_user.c +++ b/samples/bpf/test_overhead_user.c @@ -18,10 +18,14 @@ #include #include #include -#include "bpf_load.h" +#include #define MAX_CNT 1000000 +static struct bpf_link *links[2]; +static struct bpf_object *obj; +static int cnt; + static __u64 time_get_ns(void) { struct timespec ts; @@ -115,20 +119,54 @@ static void run_perf_test(int tasks, int flags) } } +static int load_progs(char *filename) +{ + struct bpf_program *prog; + int err = 0; + + obj = bpf_object__open_file(filename, NULL); + err = libbpf_get_error(obj); + if (err < 0) { + fprintf(stderr, "ERROR: opening BPF object file failed\n"); + return err; + } + + /* load BPF program */ + err = bpf_object__load(obj); + if (err < 0) { + fprintf(stderr, "ERROR: loading BPF object file failed\n"); + return err; + } + + bpf_object__for_each_program(prog, obj) { + links[cnt] = bpf_program__attach(prog); + err = libbpf_get_error(links[cnt]); + if (err < 0) { + fprintf(stderr, "ERROR: bpf_program__attach failed\n"); + links[cnt] = NULL; + return err; + } + cnt++; + } + + return err; +} + static void unload_progs(void) { - close(prog_fd[0]); - close(prog_fd[1]); - close(event_fd[0]); - close(event_fd[1]); + while (cnt) + bpf_link__destroy(links[--cnt]); + + bpf_object__close(obj); } int main(int argc, char **argv) { struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY}; - char filename[256]; - int num_cpu = 8; + int num_cpu = sysconf(_SC_NPROCESSORS_ONLN); int test_flags = ~0; + char filename[256]; + int err = 0; setrlimit(RLIMIT_MEMLOCK, &r); @@ -145,38 +183,36 @@ int main(int argc, char **argv) if (test_flags & 0xC) { snprintf(filename, sizeof(filename), "%s_kprobe_kern.o", argv[0]); - if (load_bpf_file(filename)) { - printf("%s", bpf_log_buf); - return 1; - } + printf("w/KPROBE\n"); - run_perf_test(num_cpu, test_flags >> 2); + err = load_progs(filename); + if (!err) + run_perf_test(num_cpu, test_flags >> 2); + unload_progs(); } if (test_flags & 0x30) { snprintf(filename, sizeof(filename), "%s_tp_kern.o", argv[0]); - if (load_bpf_file(filename)) { - printf("%s", bpf_log_buf); - return 1; - } printf("w/TRACEPOINT\n"); - run_perf_test(num_cpu, test_flags >> 4); + err = load_progs(filename); + if (!err) + run_perf_test(num_cpu, test_flags >> 4); + unload_progs(); } if (test_flags & 0xC0) { snprintf(filename, sizeof(filename), "%s_raw_tp_kern.o", argv[0]); - if (load_bpf_file(filename)) { - printf("%s", bpf_log_buf); - return 1; - } printf("w/RAW_TRACEPOINT\n"); - run_perf_test(num_cpu, test_flags >> 6); + err = load_progs(filename); + if (!err) + run_perf_test(num_cpu, test_flags >> 6); + unload_progs(); } - return 0; + return err; }