From: Song Liu <songliubraving@fb.com> Introduce 'perf stat -b' option, which counts events for BPF programs, like: [root@localhost ~]# ~/perf stat -e ref-cycles,cycles -b 254 -I 1000 1.487903822 115,200 ref-cycles 1.487903822 86,012 cycles 2.489147029 80,560 ref-cycles 2.489147029 73,784 cycles 3.490341825 60,720 ref-cycles 3.490341825 37,797 cycles 4.491540887 37,120 ref-cycles 4.491540887 31,963 cycles The example above counts 'cycles' and 'ref-cycles' of BPF program of id 254. This is similar to bpftool-prog-profile command, but more flexible. 'perf stat -b' creates per-cpu perf_event and loads fentry/fexit BPF programs (monitor-progs) to the target BPF program (target-prog). The monitor-progs read perf_event before and after the target-prog, and aggregate the difference in a BPF map. Then the user space reads data from these maps. A new 'struct bpf_counter' is introduced to provide a common interface that uses BPF programs/maps to count perf events. Committer notes: Removed all but bpf_counter.h includes from evsel.h, not needed at all. Also BPF map lookups for PERCPU_ARRAYs need to have as its value receive buffer passed to the kernel libbpf_num_possible_cpus() entries, not evsel__nr_cpus(evsel), as the former uses /sys/devices/system/cpu/possible while the later uses /sys/devices/system/cpu/online, which may be less than the 'possible' number making the bpf map lookup overwrite memory and cause hard to debug memory corruption. We need to continue using evsel__nr_cpus(evsel) when accessing the perf_counts array tho, not to overwrite another are of memory :-) Signed-off-by: Song Liu <songliubraving@fb.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Link: https://lore.kernel.org/lkml/20210120163031.GU12699@kernel.org/ Acked-by: Namhyung Kim <namhyung@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: kernel-team@fb.com Link: http://lore.kernel.org/lkml/20201229214214.3413833-4-songliubraving@fb.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> --- tools/perf/Documentation/perf-stat.txt | 18 + tools/perf/Makefile.perf | 2 +- tools/perf/builtin-stat.c | 81 ++++- tools/perf/util/Build | 1 + tools/perf/util/bpf_counter.c | 314 ++++++++++++++++++ tools/perf/util/bpf_counter.h | 72 ++++ .../util/bpf_skel/bpf_prog_profiler.bpf.c | 93 ++++++ tools/perf/util/evsel.c | 5 + tools/perf/util/evsel.h | 5 + tools/perf/util/python.c | 21 ++ tools/perf/util/stat-display.c | 4 +- tools/perf/util/stat.c | 2 +- tools/perf/util/target.c | 34 +- tools/perf/util/target.h | 10 + 14 files changed, 645 insertions(+), 17 deletions(-) create mode 100644 tools/perf/util/bpf_counter.c create mode 100644 tools/perf/util/bpf_counter.h create mode 100644 tools/perf/util/bpf_skel/bpf_prog_profiler.bpf.c diff --git a/tools/perf/Documentation/perf-stat.txt b/tools/perf/Documentation/perf-stat.txt index f9bcd95bf352..5bfc0357694b 100644 --- a/tools/perf/Documentation/perf-stat.txt +++ b/tools/perf/Documentation/perf-stat.txt @@ -75,6 +75,24 @@ report:: --tid=<tid>:: stat events on existing thread id (comma separated list) +-b:: +--bpf-prog:: + stat events on existing bpf program id (comma separated list), + requiring root rights. bpftool-prog could be used to find program + id all bpf programs in the system. For example: + + # bpftool prog | head -n 1 + 17247: tracepoint name sys_enter tag 192d548b9d754067 gpl + + # perf stat -e cycles,instructions --bpf-prog 17247 --timeout 1000 + + Performance counter stats for 'BPF program(s) 17247': + + 85,967 cycles + 28,982 instructions # 0.34 insn per cycle + + 1.102235068 seconds time elapsed + ifdef::HAVE_LIBPFM[] --pfm-events events:: Select a PMU event using libpfm4 syntax (see http://perfmon2.sf.net) diff --git a/tools/perf/Makefile.perf b/tools/perf/Makefile.perf index e22457ebee45..0407e9aaaeef 100644 --- a/tools/perf/Makefile.perf +++ b/tools/perf/Makefile.perf @@ -1015,7 +1015,7 @@ python-clean: SKEL_OUT := $(abspath $(OUTPUT)util/bpf_skel) SKEL_TMP_OUT := $(abspath $(SKEL_OUT)/.tmp) -SKELETONS := +SKELETONS := $(SKEL_OUT)/bpf_prog_profiler.skel.h ifdef BUILD_BPF_SKEL BPFTOOL := $(SKEL_TMP_OUT)/bootstrap/bpftool diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c index a5dafba23d93..780f9a934244 100644 --- a/tools/perf/builtin-stat.c +++ b/tools/perf/builtin-stat.c @@ -67,6 +67,7 @@ #include "util/top.h" #include "util/affinity.h" #include "util/pfm.h" +#include "util/bpf_counter.h" #include "asm/bug.h" #include <linux/time64.h> @@ -409,12 +410,32 @@ static int read_affinity_counters(struct timespec *rs) return 0; } +static int read_bpf_map_counters(void) +{ + struct evsel *counter; + int err; + + evlist__for_each_entry(evsel_list, counter) { + err = bpf_counter__read(counter); + if (err) + return err; + } + return 0; +} + static void read_counters(struct timespec *rs) { struct evsel *counter; + int err; - if (!stat_config.stop_read_counter && (read_affinity_counters(rs) < 0)) - return; + if (!stat_config.stop_read_counter) { + if (target__has_bpf(&target)) + err = read_bpf_map_counters(); + else + err = read_affinity_counters(rs); + if (err < 0) + return; + } evlist__for_each_entry(evsel_list, counter) { if (counter->err) @@ -496,11 +517,22 @@ static bool handle_interval(unsigned int interval, int *times) return false; } -static void enable_counters(void) +static int enable_counters(void) { + struct evsel *evsel; + int err; + + if (target__has_bpf(&target)) { + evlist__for_each_entry(evsel_list, evsel) { + err = bpf_counter__enable(evsel); + if (err) + return err; + } + } + if (stat_config.initial_delay < 0) { pr_info(EVLIST_DISABLED_MSG); - return; + return 0; } if (stat_config.initial_delay > 0) { @@ -518,6 +550,7 @@ static void enable_counters(void) if (stat_config.initial_delay > 0) pr_info(EVLIST_ENABLED_MSG); } + return 0; } static void disable_counters(void) @@ -720,7 +753,7 @@ static int __run_perf_stat(int argc, const char **argv, int run_idx) const bool forks = (argc > 0); bool is_pipe = STAT_RECORD ? perf_stat.data.is_pipe : false; struct affinity affinity; - int i, cpu; + int i, cpu, err; bool second_pass = false; if (forks) { @@ -738,6 +771,13 @@ static int __run_perf_stat(int argc, const char **argv, int run_idx) if (affinity__setup(&affinity) < 0) return -1; + if (target__has_bpf(&target)) { + evlist__for_each_entry(evsel_list, counter) { + if (bpf_counter__load(counter, &target)) + return -1; + } + } + evlist__for_each_cpu (evsel_list, i, cpu) { affinity__set(&affinity, cpu); @@ -853,7 +893,7 @@ static int __run_perf_stat(int argc, const char **argv, int run_idx) } if (STAT_RECORD) { - int err, fd = perf_data__fd(&perf_stat.data); + int fd = perf_data__fd(&perf_stat.data); if (is_pipe) { err = perf_header__write_pipe(perf_data__fd(&perf_stat.data)); @@ -879,7 +919,9 @@ static int __run_perf_stat(int argc, const char **argv, int run_idx) if (forks) { perf_evlist__start_workload(evsel_list); - enable_counters(); + err = enable_counters(); + if (err) + return -1; if (interval || timeout || evlist__ctlfd_initialized(evsel_list)) status = dispatch_events(forks, timeout, interval, ×); @@ -898,7 +940,9 @@ static int __run_perf_stat(int argc, const char **argv, int run_idx) if (WIFSIGNALED(status)) psignal(WTERMSIG(status), argv[0]); } else { - enable_counters(); + err = enable_counters(); + if (err) + return -1; status = dispatch_events(forks, timeout, interval, ×); } @@ -1089,6 +1133,10 @@ static struct option stat_options[] = { "stat events on existing process id"), OPT_STRING('t', "tid", &target.tid, "tid", "stat events on existing thread id"), +#ifdef HAVE_BPF_SKEL + OPT_STRING('b', "bpf-prog", &target.bpf_str, "bpf-prog-id", + "stat events on existing bpf program id"), +#endif OPT_BOOLEAN('a', "all-cpus", &target.system_wide, "system-wide collection from all CPUs"), OPT_BOOLEAN('g', "group", &group, @@ -2060,11 +2108,12 @@ int cmd_stat(int argc, const char **argv) "perf stat [<options>] [<command>]", NULL }; - int status = -EINVAL, run_idx; + int status = -EINVAL, run_idx, err; const char *mode; FILE *output = stderr; unsigned int interval, timeout; const char * const stat_subcommands[] = { "record", "report" }; + char errbuf[BUFSIZ]; setlocale(LC_ALL, ""); @@ -2175,6 +2224,12 @@ int cmd_stat(int argc, const char **argv) } else if (big_num_opt == 0) /* User passed --no-big-num */ stat_config.big_num = false; + err = target__validate(&target); + if (err) { + target__strerror(&target, err, errbuf, BUFSIZ); + pr_warning("%s\n", errbuf); + } + setup_system_wide(argc); /* @@ -2245,7 +2300,6 @@ int cmd_stat(int argc, const char **argv) goto out; } - target__validate(&target); if ((stat_config.aggr_mode == AGGR_THREAD) && (target.system_wide)) target.per_thread = true; @@ -2377,9 +2431,10 @@ int cmd_stat(int argc, const char **argv) * tools remain -acme */ int fd = perf_data__fd(&perf_stat.data); - int err = perf_event__synthesize_kernel_mmap((void *)&perf_stat, - process_synthesized_event, - &perf_stat.session->machines.host); + + err = perf_event__synthesize_kernel_mmap((void *)&perf_stat, + process_synthesized_event, + &perf_stat.session->machines.host); if (err) { pr_warning("Couldn't synthesize the kernel mmap record, harmless, " "older tools may produce warnings about this file\n."); diff --git a/tools/perf/util/Build b/tools/perf/util/Build index fe253e003d72..816f2e01ac46 100644 --- a/tools/perf/util/Build +++ b/tools/perf/util/Build @@ -139,6 +139,7 @@ perf-y += clockid.o perf-$(CONFIG_LIBBPF) += bpf-loader.o perf-$(CONFIG_LIBBPF) += bpf_map.o +perf-$(CONFIG_PERF_BPF_SKEL) += bpf_counter.o perf-$(CONFIG_BPF_PROLOGUE) += bpf-prologue.o perf-$(CONFIG_LIBELF) += symbol-elf.o perf-$(CONFIG_LIBELF) += probe-file.o diff --git a/tools/perf/util/bpf_counter.c b/tools/perf/util/bpf_counter.c new file mode 100644 index 000000000000..04f89120b323 --- /dev/null +++ b/tools/perf/util/bpf_counter.c @@ -0,0 +1,314 @@ +// SPDX-License-Identifier: GPL-2.0 + +/* Copyright (c) 2019 Facebook */ + +#include <assert.h> +#include <limits.h> +#include <unistd.h> +#include <sys/time.h> +#include <sys/resource.h> +#include <linux/err.h> +#include <linux/zalloc.h> +#include <bpf/bpf.h> +#include <bpf/btf.h> +#include <bpf/libbpf.h> + +#include "bpf_counter.h" +#include "counts.h" +#include "debug.h" +#include "evsel.h" +#include "target.h" + +#include "bpf_skel/bpf_prog_profiler.skel.h" + +static inline void *u64_to_ptr(__u64 ptr) +{ + return (void *)(unsigned long)ptr; +} + +static void set_max_rlimit(void) +{ + struct rlimit rinf = { RLIM_INFINITY, RLIM_INFINITY }; + + setrlimit(RLIMIT_MEMLOCK, &rinf); +} + +static struct bpf_counter *bpf_counter_alloc(void) +{ + struct bpf_counter *counter; + + counter = zalloc(sizeof(*counter)); + if (counter) + INIT_LIST_HEAD(&counter->list); + return counter; +} + +static int bpf_program_profiler__destroy(struct evsel *evsel) +{ + struct bpf_counter *counter, *tmp; + + list_for_each_entry_safe(counter, tmp, + &evsel->bpf_counter_list, list) { + list_del_init(&counter->list); + bpf_prog_profiler_bpf__destroy(counter->skel); + free(counter); + } + assert(list_empty(&evsel->bpf_counter_list)); + + return 0; +} + +static char *bpf_target_prog_name(int tgt_fd) +{ + struct bpf_prog_info_linear *info_linear; + struct bpf_func_info *func_info; + const struct btf_type *t; + char *name = NULL; + struct btf *btf; + + info_linear = bpf_program__get_prog_info_linear( + tgt_fd, 1UL << BPF_PROG_INFO_FUNC_INFO); + if (IS_ERR_OR_NULL(info_linear)) { + pr_debug("failed to get info_linear for prog FD %d\n", tgt_fd); + return NULL; + } + + if (info_linear->info.btf_id == 0 || + btf__get_from_id(info_linear->info.btf_id, &btf)) { + pr_debug("prog FD %d doesn't have valid btf\n", tgt_fd); + goto out; + } + + func_info = u64_to_ptr(info_linear->info.func_info); + t = btf__type_by_id(btf, func_info[0].type_id); + if (!t) { + pr_debug("btf %d doesn't have type %d\n", + info_linear->info.btf_id, func_info[0].type_id); + goto out; + } + name = strdup(btf__name_by_offset(btf, t->name_off)); +out: + free(info_linear); + return name; +} + +static int bpf_program_profiler_load_one(struct evsel *evsel, u32 prog_id) +{ + struct bpf_prog_profiler_bpf *skel; + struct bpf_counter *counter; + struct bpf_program *prog; + char *prog_name; + int prog_fd; + int err; + + prog_fd = bpf_prog_get_fd_by_id(prog_id); + if (prog_fd < 0) { + pr_err("Failed to open fd for bpf prog %u\n", prog_id); + return -1; + } + counter = bpf_counter_alloc(); + if (!counter) { + close(prog_fd); + return -1; + } + + skel = bpf_prog_profiler_bpf__open(); + if (!skel) { + pr_err("Failed to open bpf skeleton\n"); + goto err_out; + } + + skel->rodata->num_cpu = evsel__nr_cpus(evsel); + + bpf_map__resize(skel->maps.events, evsel__nr_cpus(evsel)); + bpf_map__resize(skel->maps.fentry_readings, 1); + bpf_map__resize(skel->maps.accum_readings, 1); + + prog_name = bpf_target_prog_name(prog_fd); + if (!prog_name) { + pr_err("Failed to get program name for bpf prog %u. Does it have BTF?\n", prog_id); + goto err_out; + } + + bpf_object__for_each_program(prog, skel->obj) { + err = bpf_program__set_attach_target(prog, prog_fd, prog_name); + if (err) { + pr_err("bpf_program__set_attach_target failed.\n" + "Does bpf prog %u have BTF?\n", prog_id); + goto err_out; + } + } + set_max_rlimit(); + err = bpf_prog_profiler_bpf__load(skel); + if (err) { + pr_err("bpf_prog_profiler_bpf__load failed\n"); + goto err_out; + } + + assert(skel != NULL); + counter->skel = skel; + list_add(&counter->list, &evsel->bpf_counter_list); + close(prog_fd); + return 0; +err_out: + bpf_prog_profiler_bpf__destroy(skel); + free(counter); + close(prog_fd); + return -1; +} + +static int bpf_program_profiler__load(struct evsel *evsel, struct target *target) +{ + char *bpf_str, *bpf_str_, *tok, *saveptr = NULL, *p; + u32 prog_id; + int ret; + + bpf_str_ = bpf_str = strdup(target->bpf_str); + if (!bpf_str) + return -1; + + while ((tok = strtok_r(bpf_str, ",", &saveptr)) != NULL) { + prog_id = strtoul(tok, &p, 10); + if (prog_id == 0 || prog_id == UINT_MAX || + (*p != '\0' && *p != ',')) { + pr_err("Failed to parse bpf prog ids %s\n", + target->bpf_str); + return -1; + } + + ret = bpf_program_profiler_load_one(evsel, prog_id); + if (ret) { + bpf_program_profiler__destroy(evsel); + free(bpf_str_); + return -1; + } + bpf_str = NULL; + } + free(bpf_str_); + return 0; +} + +static int bpf_program_profiler__enable(struct evsel *evsel) +{ + struct bpf_counter *counter; + int ret; + + list_for_each_entry(counter, &evsel->bpf_counter_list, list) { + assert(counter->skel != NULL); + ret = bpf_prog_profiler_bpf__attach(counter->skel); + if (ret) { + bpf_program_profiler__destroy(evsel); + return ret; + } + } + return 0; +} + +static int bpf_program_profiler__read(struct evsel *evsel) +{ + // perf_cpu_map uses /sys/devices/system/cpu/online + int num_cpu = evsel__nr_cpus(evsel); + // BPF_MAP_TYPE_PERCPU_ARRAY uses /sys/devices/system/cpu/possible + // Sometimes possible > online, like on a Ryzen 3900X that has 24 + // threads but its possible showed 0-31 -acme + int num_cpu_bpf = libbpf_num_possible_cpus(); + struct bpf_perf_event_value values[num_cpu_bpf]; + struct bpf_counter *counter; + int reading_map_fd; + __u32 key = 0; + int err, cpu; + + if (list_empty(&evsel->bpf_counter_list)) + return -EAGAIN; + + for (cpu = 0; cpu < num_cpu; cpu++) { + perf_counts(evsel->counts, cpu, 0)->val = 0; + perf_counts(evsel->counts, cpu, 0)->ena = 0; + perf_counts(evsel->counts, cpu, 0)->run = 0; + } + list_for_each_entry(counter, &evsel->bpf_counter_list, list) { + struct bpf_prog_profiler_bpf *skel = counter->skel; + + assert(skel != NULL); + reading_map_fd = bpf_map__fd(skel->maps.accum_readings); + + err = bpf_map_lookup_elem(reading_map_fd, &key, values); + if (err) { + pr_err("failed to read value\n"); + return err; + } + + for (cpu = 0; cpu < num_cpu; cpu++) { + perf_counts(evsel->counts, cpu, 0)->val += values[cpu].counter; + perf_counts(evsel->counts, cpu, 0)->ena += values[cpu].enabled; + perf_counts(evsel->counts, cpu, 0)->run += values[cpu].running; + } + } + return 0; +} + +static int bpf_program_profiler__install_pe(struct evsel *evsel, int cpu, + int fd) +{ + struct bpf_prog_profiler_bpf *skel; + struct bpf_counter *counter; + int ret; + + list_for_each_entry(counter, &evsel->bpf_counter_list, list) { + skel = counter->skel; + assert(skel != NULL); + + ret = bpf_map_update_elem(bpf_map__fd(skel->maps.events), + &cpu, &fd, BPF_ANY); + if (ret) + return ret; + } + return 0; +} + +struct bpf_counter_ops bpf_program_profiler_ops = { + .load = bpf_program_profiler__load, + .enable = bpf_program_profiler__enable, + .read = bpf_program_profiler__read, + .destroy = bpf_program_profiler__destroy, + .install_pe = bpf_program_profiler__install_pe, +}; + +int bpf_counter__install_pe(struct evsel *evsel, int cpu, int fd) +{ + if (list_empty(&evsel->bpf_counter_list)) + return 0; + return evsel->bpf_counter_ops->install_pe(evsel, cpu, fd); +} + +int bpf_counter__load(struct evsel *evsel, struct target *target) +{ + if (target__has_bpf(target)) + evsel->bpf_counter_ops = &bpf_program_profiler_ops; + + if (evsel->bpf_counter_ops) + return evsel->bpf_counter_ops->load(evsel, target); + return 0; +} + +int bpf_counter__enable(struct evsel *evsel) +{ + if (list_empty(&evsel->bpf_counter_list)) + return 0; + return evsel->bpf_counter_ops->enable(evsel); +} + +int bpf_counter__read(struct evsel *evsel) +{ + if (list_empty(&evsel->bpf_counter_list)) + return -EAGAIN; + return evsel->bpf_counter_ops->read(evsel); +} + +void bpf_counter__destroy(struct evsel *evsel) +{ + if (list_empty(&evsel->bpf_counter_list)) + return; + evsel->bpf_counter_ops->destroy(evsel); + evsel->bpf_counter_ops = NULL; +} diff --git a/tools/perf/util/bpf_counter.h b/tools/perf/util/bpf_counter.h new file mode 100644 index 000000000000..2eca210e5dc1 --- /dev/null +++ b/tools/perf/util/bpf_counter.h @@ -0,0 +1,72 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __PERF_BPF_COUNTER_H +#define __PERF_BPF_COUNTER_H 1 + +#include <linux/list.h> + +struct evsel; +struct target; +struct bpf_counter; + +typedef int (*bpf_counter_evsel_op)(struct evsel *evsel); +typedef int (*bpf_counter_evsel_target_op)(struct evsel *evsel, + struct target *target); +typedef int (*bpf_counter_evsel_install_pe_op)(struct evsel *evsel, + int cpu, + int fd); + +struct bpf_counter_ops { + bpf_counter_evsel_target_op load; + bpf_counter_evsel_op enable; + bpf_counter_evsel_op read; + bpf_counter_evsel_op destroy; + bpf_counter_evsel_install_pe_op install_pe; +}; + +struct bpf_counter { + void *skel; + struct list_head list; +}; + +#ifdef HAVE_BPF_SKEL + +int bpf_counter__load(struct evsel *evsel, struct target *target); +int bpf_counter__enable(struct evsel *evsel); +int bpf_counter__read(struct evsel *evsel); +void bpf_counter__destroy(struct evsel *evsel); +int bpf_counter__install_pe(struct evsel *evsel, int cpu, int fd); + +#else /* HAVE_BPF_SKEL */ + +#include<linux/err.h> + +static inline int bpf_counter__load(struct evsel *evsel __maybe_unused, + struct target *target __maybe_unused) +{ + return 0; +} + +static inline int bpf_counter__enable(struct evsel *evsel __maybe_unused) +{ + return 0; +} + +static inline int bpf_counter__read(struct evsel *evsel __maybe_unused) +{ + return -EAGAIN; +} + +static inline void bpf_counter__destroy(struct evsel *evsel __maybe_unused) +{ +} + +static inline int bpf_counter__install_pe(struct evsel *evsel __maybe_unused, + int cpu __maybe_unused, + int fd __maybe_unused) +{ + return 0; +} + +#endif /* HAVE_BPF_SKEL */ + +#endif /* __PERF_BPF_COUNTER_H */ diff --git a/tools/perf/util/bpf_skel/bpf_prog_profiler.bpf.c b/tools/perf/util/bpf_skel/bpf_prog_profiler.bpf.c new file mode 100644 index 000000000000..c7cec92d0236 --- /dev/null +++ b/tools/perf/util/bpf_skel/bpf_prog_profiler.bpf.c @@ -0,0 +1,93 @@ +// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +// Copyright (c) 2020 Facebook +#include <linux/bpf.h> +#include <bpf/bpf_helpers.h> +#include <bpf/bpf_tracing.h> + +/* map of perf event fds, num_cpu * num_metric entries */ +struct { + __uint(type, BPF_MAP_TYPE_PERF_EVENT_ARRAY); + __uint(key_size, sizeof(__u32)); + __uint(value_size, sizeof(int)); +} events SEC(".maps"); + +/* readings at fentry */ +struct { + __uint(type, BPF_MAP_TYPE_PERCPU_ARRAY); + __uint(key_size, sizeof(__u32)); + __uint(value_size, sizeof(struct bpf_perf_event_value)); + __uint(max_entries, 1); +} fentry_readings SEC(".maps"); + +/* accumulated readings */ +struct { + __uint(type, BPF_MAP_TYPE_PERCPU_ARRAY); + __uint(key_size, sizeof(__u32)); + __uint(value_size, sizeof(struct bpf_perf_event_value)); + __uint(max_entries, 1); +} accum_readings SEC(".maps"); + +const volatile __u32 num_cpu = 1; + +SEC("fentry/XXX") +int BPF_PROG(fentry_XXX) +{ + __u32 key = bpf_get_smp_processor_id(); + struct bpf_perf_event_value *ptr; + __u32 zero = 0; + long err; + + /* look up before reading, to reduce error */ + ptr = bpf_map_lookup_elem(&fentry_readings, &zero); + if (!ptr) + return 0; + + err = bpf_perf_event_read_value(&events, key, ptr, sizeof(*ptr)); + if (err) + return 0; + + return 0; +} + +static inline void +fexit_update_maps(struct bpf_perf_event_value *after) +{ + struct bpf_perf_event_value *before, diff, *accum; + __u32 zero = 0; + + before = bpf_map_lookup_elem(&fentry_readings, &zero); + /* only account samples with a valid fentry_reading */ + if (before && before->counter) { + struct bpf_perf_event_value *accum; + + diff.counter = after->counter - before->counter; + diff.enabled = after->enabled - before->enabled; + diff.running = after->running - before->running; + + accum = bpf_map_lookup_elem(&accum_readings, &zero); + if (accum) { + accum->counter += diff.counter; + accum->enabled += diff.enabled; + accum->running += diff.running; + } + } +} + +SEC("fexit/XXX") +int BPF_PROG(fexit_XXX) +{ + struct bpf_perf_event_value reading; + __u32 cpu = bpf_get_smp_processor_id(); + __u32 one = 1, zero = 0; + int err; + + /* read all events before updating the maps, to reduce error */ + err = bpf_perf_event_read_value(&events, cpu, &reading, sizeof(reading)); + if (err) + return 0; + + fexit_update_maps(&reading); + return 0; +} + +char LICENSE[] SEC("license") = "Dual BSD/GPL"; diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c index 12daf40ae89b..ae8ca337d5c0 100644 --- a/tools/perf/util/evsel.c +++ b/tools/perf/util/evsel.c @@ -25,6 +25,7 @@ #include <stdlib.h> #include <perf/evsel.h> #include "asm/bug.h" +#include "bpf_counter.h" #include "callchain.h" #include "cgroup.h" #include "counts.h" @@ -247,6 +248,7 @@ void evsel__init(struct evsel *evsel, evsel->bpf_obj = NULL; evsel->bpf_fd = -1; INIT_LIST_HEAD(&evsel->config_terms); + INIT_LIST_HEAD(&evsel->bpf_counter_list); perf_evsel__object.init(evsel); evsel->sample_size = __evsel__sample_size(attr->sample_type); evsel__calc_id_pos(evsel); @@ -1392,6 +1394,7 @@ void evsel__exit(struct evsel *evsel) { assert(list_empty(&evsel->core.node)); assert(evsel->evlist == NULL); + bpf_counter__destroy(evsel); evsel__free_counts(evsel); perf_evsel__free_fd(&evsel->core); perf_evsel__free_id(&evsel->core); @@ -1819,6 +1822,8 @@ static int evsel__open_cpu(struct evsel *evsel, struct perf_cpu_map *cpus, FD(evsel, cpu, thread) = fd; + bpf_counter__install_pe(evsel, cpu, fd); + if (unlikely(test_attr__enabled)) { test_attr__open(&evsel->core.attr, pid, cpus->map[cpu].cpu, fd, group_fd, flags); diff --git a/tools/perf/util/evsel.h b/tools/perf/util/evsel.h index b0d1c67f7617..3eadaa7bd477 100644 --- a/tools/perf/util/evsel.h +++ b/tools/perf/util/evsel.h @@ -17,6 +17,8 @@ struct cgroup; struct perf_counts; struct perf_stat_evsel; union perf_event; +struct bpf_counter_ops; +struct target; typedef int (evsel__sb_cb_t)(union perf_event *event, void *data); @@ -128,6 +130,8 @@ struct evsel { * See also evsel__has_callchain(). */ __u64 synth_sample_type; + struct list_head bpf_counter_list; + struct bpf_counter_ops *bpf_counter_ops; }; struct perf_missing_features { @@ -430,4 +434,5 @@ static inline bool evsel__is_dummy_event(struct evsel *evsel) struct perf_env *evsel__env(struct evsel *evsel); int evsel__store_ids(struct evsel *evsel, struct evlist *evlist); + #endif /* __PERF_EVSEL_H */ diff --git a/tools/perf/util/python.c b/tools/perf/util/python.c index ab146924981a..c3979b15863a 100644 --- a/tools/perf/util/python.c +++ b/tools/perf/util/python.c @@ -79,6 +79,27 @@ int metricgroup__copy_metric_events(struct evlist *evlist, struct cgroup *cgrp, return 0; } +/* + * XXX: All these evsel destructors need some better mechanism, like a linked + * list of destructors registered when the relevant code indeed is used instead + * of having more and more calls in perf_evsel__delete(). -- acme + * + * For now, add some more: + * + * Not to drag the BPF bandwagon... + */ +void bpf_counter__destroy(struct evsel *evsel); +int bpf_counter__install_pe(struct evsel *evsel, int cpu, int fd); + +void bpf_counter__destroy(struct evsel *evsel __maybe_unused) +{ +} + +int bpf_counter__install_pe(struct evsel *evsel __maybe_unused, int cpu __maybe_unused, int fd __maybe_unused) +{ + return 0; +} + /* * Support debug printing even though util/debug.c is not linked. That means * implementing 'verbose' and 'eprintf'. diff --git a/tools/perf/util/stat-display.c b/tools/perf/util/stat-display.c index e84206f957b2..191e1b702b55 100644 --- a/tools/perf/util/stat-display.c +++ b/tools/perf/util/stat-display.c @@ -1027,7 +1027,9 @@ static void print_header(struct perf_stat_config *config, if (!config->csv_output) { fprintf(output, "\n"); fprintf(output, " Performance counter stats for "); - if (_target->system_wide) + if (_target->bpf_str) + fprintf(output, "\'BPF program(s) %s", _target->bpf_str); + else if (_target->system_wide) fprintf(output, "\'system wide"); else if (_target->cpu_list) fprintf(output, "\'CPU(s) %s", _target->cpu_list); diff --git a/tools/perf/util/stat.c b/tools/perf/util/stat.c index be326227b055..e95dc23dd478 100644 --- a/tools/perf/util/stat.c +++ b/tools/perf/util/stat.c @@ -527,7 +527,7 @@ int create_perf_stat_counter(struct evsel *evsel, if (leader->core.nr_members > 1) attr->read_format |= PERF_FORMAT_ID|PERF_FORMAT_GROUP; - attr->inherit = !config->no_inherit; + attr->inherit = !config->no_inherit && list_empty(&evsel->bpf_counter_list); /* * Some events get initialized with sample_(period/type) set, diff --git a/tools/perf/util/target.c b/tools/perf/util/target.c index a3db13dea937..0f383418e3df 100644 --- a/tools/perf/util/target.c +++ b/tools/perf/util/target.c @@ -56,6 +56,34 @@ enum target_errno target__validate(struct target *target) ret = TARGET_ERRNO__UID_OVERRIDE_SYSTEM; } + /* BPF and CPU are mutually exclusive */ + if (target->bpf_str && target->cpu_list) { + target->cpu_list = NULL; + if (ret == TARGET_ERRNO__SUCCESS) + ret = TARGET_ERRNO__BPF_OVERRIDE_CPU; + } + + /* BPF and PID/TID are mutually exclusive */ + if (target->bpf_str && target->tid) { + target->tid = NULL; + if (ret == TARGET_ERRNO__SUCCESS) + ret = TARGET_ERRNO__BPF_OVERRIDE_PID; + } + + /* BPF and UID are mutually exclusive */ + if (target->bpf_str && target->uid_str) { + target->uid_str = NULL; + if (ret == TARGET_ERRNO__SUCCESS) + ret = TARGET_ERRNO__BPF_OVERRIDE_UID; + } + + /* BPF and THREADS are mutually exclusive */ + if (target->bpf_str && target->per_thread) { + target->per_thread = false; + if (ret == TARGET_ERRNO__SUCCESS) + ret = TARGET_ERRNO__BPF_OVERRIDE_THREAD; + } + /* THREAD and SYSTEM/CPU are mutually exclusive */ if (target->per_thread && (target->system_wide || target->cpu_list)) { target->per_thread = false; @@ -109,6 +137,10 @@ static const char *target__error_str[] = { "PID/TID switch overriding SYSTEM", "UID switch overriding SYSTEM", "SYSTEM/CPU switch overriding PER-THREAD", + "BPF switch overriding CPU", + "BPF switch overriding PID/TID", + "BPF switch overriding UID", + "BPF switch overriding THREAD", "Invalid User: %s", "Problems obtaining information for user %s", }; @@ -134,7 +166,7 @@ int target__strerror(struct target *target, int errnum, switch (errnum) { case TARGET_ERRNO__PID_OVERRIDE_CPU ... - TARGET_ERRNO__SYSTEM_OVERRIDE_THREAD: + TARGET_ERRNO__BPF_OVERRIDE_THREAD: snprintf(buf, buflen, "%s", msg); break; diff --git a/tools/perf/util/target.h b/tools/perf/util/target.h index 6ef01a83b24e..f132c6c2eef8 100644 --- a/tools/perf/util/target.h +++ b/tools/perf/util/target.h @@ -10,6 +10,7 @@ struct target { const char *tid; const char *cpu_list; const char *uid_str; + const char *bpf_str; uid_t uid; bool system_wide; bool uses_mmap; @@ -36,6 +37,10 @@ enum target_errno { TARGET_ERRNO__PID_OVERRIDE_SYSTEM, TARGET_ERRNO__UID_OVERRIDE_SYSTEM, TARGET_ERRNO__SYSTEM_OVERRIDE_THREAD, + TARGET_ERRNO__BPF_OVERRIDE_CPU, + TARGET_ERRNO__BPF_OVERRIDE_PID, + TARGET_ERRNO__BPF_OVERRIDE_UID, + TARGET_ERRNO__BPF_OVERRIDE_THREAD, /* for target__parse_uid() */ TARGET_ERRNO__INVALID_UID, @@ -59,6 +64,11 @@ static inline bool target__has_cpu(struct target *target) return target->system_wide || target->cpu_list; } +static inline bool target__has_bpf(struct target *target) +{ + return target->bpf_str; +} + static inline bool target__none(struct target *target) { return !target__has_task(target) && !target__has_cpu(target); -- 2.34.1