| // SPDX-License-Identifier: GPL-2.0-only |
| /* Copyright (c) 2016 Facebook |
| */ |
| #include <stdio.h> |
| #include <unistd.h> |
| #include <stdlib.h> |
| #include <stdbool.h> |
| #include <string.h> |
| #include <fcntl.h> |
| #include <poll.h> |
| #include <sys/ioctl.h> |
| #include <linux/perf_event.h> |
| #include <linux/bpf.h> |
| #include <signal.h> |
| #include <assert.h> |
| #include <errno.h> |
| #include <sys/resource.h> |
| #include "libbpf.h" |
| #include "bpf_load.h" |
| #include "perf-sys.h" |
| #include "trace_helpers.h" |
| |
| #define SAMPLE_FREQ 50 |
| |
| static bool sys_read_seen, sys_write_seen; |
| |
| static void print_ksym(__u64 addr) |
| { |
| struct ksym *sym; |
| |
| if (!addr) |
| return; |
| sym = ksym_search(addr); |
| if (!sym) { |
| printf("ksym not found. Is kallsyms loaded?\n"); |
| return; |
| } |
| |
| printf("%s;", sym->name); |
| if (!strstr(sym->name, "sys_read")) |
| sys_read_seen = true; |
| else if (!strstr(sym->name, "sys_write")) |
| sys_write_seen = true; |
| } |
| |
| static void print_addr(__u64 addr) |
| { |
| if (!addr) |
| return; |
| printf("%llx;", addr); |
| } |
| |
| #define TASK_COMM_LEN 16 |
| |
| struct key_t { |
| char comm[TASK_COMM_LEN]; |
| __u32 kernstack; |
| __u32 userstack; |
| }; |
| |
| static void print_stack(struct key_t *key, __u64 count) |
| { |
| __u64 ip[PERF_MAX_STACK_DEPTH] = {}; |
| static bool warned; |
| int i; |
| |
| printf("%3lld %s;", count, key->comm); |
| if (bpf_map_lookup_elem(map_fd[1], &key->kernstack, ip) != 0) { |
| printf("---;"); |
| } else { |
| for (i = PERF_MAX_STACK_DEPTH - 1; i >= 0; i--) |
| print_ksym(ip[i]); |
| } |
| printf("-;"); |
| if (bpf_map_lookup_elem(map_fd[1], &key->userstack, ip) != 0) { |
| printf("---;"); |
| } else { |
| for (i = PERF_MAX_STACK_DEPTH - 1; i >= 0; i--) |
| print_addr(ip[i]); |
| } |
| if (count < 6) |
| printf("\r"); |
| else |
| printf("\n"); |
| |
| if (key->kernstack == -EEXIST && !warned) { |
| printf("stackmap collisions seen. Consider increasing size\n"); |
| warned = true; |
| } else if ((int)key->kernstack < 0 && (int)key->userstack < 0) { |
| printf("err stackid %d %d\n", key->kernstack, key->userstack); |
| } |
| } |
| |
| static void int_exit(int sig) |
| { |
| kill(0, SIGKILL); |
| exit(0); |
| } |
| |
| static void print_stacks(void) |
| { |
| struct key_t key = {}, next_key; |
| __u64 value; |
| __u32 stackid = 0, next_id; |
| int fd = map_fd[0], stack_map = map_fd[1]; |
| |
| sys_read_seen = sys_write_seen = false; |
| while (bpf_map_get_next_key(fd, &key, &next_key) == 0) { |
| bpf_map_lookup_elem(fd, &next_key, &value); |
| print_stack(&next_key, value); |
| bpf_map_delete_elem(fd, &next_key); |
| key = next_key; |
| } |
| printf("\n"); |
| if (!sys_read_seen || !sys_write_seen) { |
| printf("BUG kernel stack doesn't contain sys_read() and sys_write()\n"); |
| int_exit(0); |
| } |
| |
| /* clear stack map */ |
| while (bpf_map_get_next_key(stack_map, &stackid, &next_id) == 0) { |
| bpf_map_delete_elem(stack_map, &next_id); |
| stackid = next_id; |
| } |
| } |
| |
| static inline int generate_load(void) |
| { |
| if (system("dd if=/dev/zero of=/dev/null count=5000k status=none") < 0) { |
| printf("failed to generate some load with dd: %s\n", strerror(errno)); |
| return -1; |
| } |
| |
| return 0; |
| } |
| |
| static void test_perf_event_all_cpu(struct perf_event_attr *attr) |
| { |
| int nr_cpus = sysconf(_SC_NPROCESSORS_CONF); |
| int *pmu_fd = malloc(nr_cpus * sizeof(int)); |
| int i, error = 0; |
| |
| /* system wide perf event, no need to inherit */ |
| attr->inherit = 0; |
| |
| /* open perf_event on all cpus */ |
| for (i = 0; i < nr_cpus; i++) { |
| pmu_fd[i] = sys_perf_event_open(attr, -1, i, -1, 0); |
| if (pmu_fd[i] < 0) { |
| printf("sys_perf_event_open failed\n"); |
| error = 1; |
| goto all_cpu_err; |
| } |
| assert(ioctl(pmu_fd[i], PERF_EVENT_IOC_SET_BPF, prog_fd[0]) == 0); |
| assert(ioctl(pmu_fd[i], PERF_EVENT_IOC_ENABLE) == 0); |
| } |
| |
| if (generate_load() < 0) { |
| error = 1; |
| goto all_cpu_err; |
| } |
| print_stacks(); |
| all_cpu_err: |
| for (i--; i >= 0; i--) { |
| ioctl(pmu_fd[i], PERF_EVENT_IOC_DISABLE); |
| close(pmu_fd[i]); |
| } |
| free(pmu_fd); |
| if (error) |
| int_exit(0); |
| } |
| |
| static void test_perf_event_task(struct perf_event_attr *attr) |
| { |
| int pmu_fd, error = 0; |
| |
| /* per task perf event, enable inherit so the "dd ..." command can be traced properly. |
| * Enabling inherit will cause bpf_perf_prog_read_time helper failure. |
| */ |
| attr->inherit = 1; |
| |
| /* open task bound event */ |
| pmu_fd = sys_perf_event_open(attr, 0, -1, -1, 0); |
| if (pmu_fd < 0) { |
| printf("sys_perf_event_open failed\n"); |
| int_exit(0); |
| } |
| assert(ioctl(pmu_fd, PERF_EVENT_IOC_SET_BPF, prog_fd[0]) == 0); |
| assert(ioctl(pmu_fd, PERF_EVENT_IOC_ENABLE) == 0); |
| |
| if (generate_load() < 0) { |
| error = 1; |
| goto err; |
| } |
| print_stacks(); |
| err: |
| ioctl(pmu_fd, PERF_EVENT_IOC_DISABLE); |
| close(pmu_fd); |
| if (error) |
| int_exit(0); |
| } |
| |
| static void test_bpf_perf_event(void) |
| { |
| struct perf_event_attr attr_type_hw = { |
| .sample_freq = SAMPLE_FREQ, |
| .freq = 1, |
| .type = PERF_TYPE_HARDWARE, |
| .config = PERF_COUNT_HW_CPU_CYCLES, |
| }; |
| struct perf_event_attr attr_type_sw = { |
| .sample_freq = SAMPLE_FREQ, |
| .freq = 1, |
| .type = PERF_TYPE_SOFTWARE, |
| .config = PERF_COUNT_SW_CPU_CLOCK, |
| }; |
| struct perf_event_attr attr_hw_cache_l1d = { |
| .sample_freq = SAMPLE_FREQ, |
| .freq = 1, |
| .type = PERF_TYPE_HW_CACHE, |
| .config = |
| PERF_COUNT_HW_CACHE_L1D | |
| (PERF_COUNT_HW_CACHE_OP_READ << 8) | |
| (PERF_COUNT_HW_CACHE_RESULT_ACCESS << 16), |
| }; |
| struct perf_event_attr attr_hw_cache_branch_miss = { |
| .sample_freq = SAMPLE_FREQ, |
| .freq = 1, |
| .type = PERF_TYPE_HW_CACHE, |
| .config = |
| PERF_COUNT_HW_CACHE_BPU | |
| (PERF_COUNT_HW_CACHE_OP_READ << 8) | |
| (PERF_COUNT_HW_CACHE_RESULT_MISS << 16), |
| }; |
| struct perf_event_attr attr_type_raw = { |
| .sample_freq = SAMPLE_FREQ, |
| .freq = 1, |
| .type = PERF_TYPE_RAW, |
| /* Intel Instruction Retired */ |
| .config = 0xc0, |
| }; |
| struct perf_event_attr attr_type_raw_lock_load = { |
| .sample_freq = SAMPLE_FREQ, |
| .freq = 1, |
| .type = PERF_TYPE_RAW, |
| /* Intel MEM_UOPS_RETIRED.LOCK_LOADS */ |
| .config = 0x21d0, |
| /* Request to record lock address from PEBS */ |
| .sample_type = PERF_SAMPLE_ADDR, |
| /* Record address value requires precise event */ |
| .precise_ip = 2, |
| }; |
| |
| printf("Test HW_CPU_CYCLES\n"); |
| test_perf_event_all_cpu(&attr_type_hw); |
| test_perf_event_task(&attr_type_hw); |
| |
| printf("Test SW_CPU_CLOCK\n"); |
| test_perf_event_all_cpu(&attr_type_sw); |
| test_perf_event_task(&attr_type_sw); |
| |
| printf("Test HW_CACHE_L1D\n"); |
| test_perf_event_all_cpu(&attr_hw_cache_l1d); |
| test_perf_event_task(&attr_hw_cache_l1d); |
| |
| printf("Test HW_CACHE_BPU\n"); |
| test_perf_event_all_cpu(&attr_hw_cache_branch_miss); |
| test_perf_event_task(&attr_hw_cache_branch_miss); |
| |
| printf("Test Instruction Retired\n"); |
| test_perf_event_all_cpu(&attr_type_raw); |
| test_perf_event_task(&attr_type_raw); |
| |
| printf("Test Lock Load\n"); |
| test_perf_event_all_cpu(&attr_type_raw_lock_load); |
| test_perf_event_task(&attr_type_raw_lock_load); |
| |
| printf("*** PASS ***\n"); |
| } |
| |
| |
| int main(int argc, char **argv) |
| { |
| struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY}; |
| char filename[256]; |
| |
| snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]); |
| setrlimit(RLIMIT_MEMLOCK, &r); |
| |
| signal(SIGINT, int_exit); |
| signal(SIGTERM, int_exit); |
| |
| if (load_kallsyms()) { |
| printf("failed to process /proc/kallsyms\n"); |
| return 1; |
| } |
| |
| if (load_bpf_file(filename)) { |
| printf("%s", bpf_log_buf); |
| return 2; |
| } |
| |
| if (fork() == 0) { |
| read_trace_pipe(); |
| return 0; |
| } |
| test_bpf_perf_event(); |
| int_exit(0); |
| return 0; |
| } |