v4.19.13 snapshot.
diff --git a/tools/perf/builtin-ftrace.c b/tools/perf/builtin-ftrace.c
new file mode 100644
index 0000000..f42f228
--- /dev/null
+++ b/tools/perf/builtin-ftrace.c
@@ -0,0 +1,521 @@
+/*
+ * builtin-ftrace.c
+ *
+ * Copyright (c) 2013 LG Electronics, Namhyung Kim <namhyung@kernel.org>
+ *
+ * Released under the GPL v2.
+ */
+
+#include "builtin.h"
+#include "perf.h"
+
+#include <errno.h>
+#include <unistd.h>
+#include <signal.h>
+#include <fcntl.h>
+#include <poll.h>
+
+#include "debug.h"
+#include <subcmd/parse-options.h>
+#include <api/fs/tracing_path.h>
+#include "evlist.h"
+#include "target.h"
+#include "cpumap.h"
+#include "thread_map.h"
+#include "util/config.h"
+
+
+#define DEFAULT_TRACER "function_graph"
+
+struct perf_ftrace {
+ struct perf_evlist *evlist;
+ struct target target;
+ const char *tracer;
+ struct list_head filters;
+ struct list_head notrace;
+ struct list_head graph_funcs;
+ struct list_head nograph_funcs;
+ int graph_depth;
+};
+
+struct filter_entry {
+ struct list_head list;
+ char name[];
+};
+
+static bool done;
+
+static void sig_handler(int sig __maybe_unused)
+{
+ done = true;
+}
+
+/*
+ * perf_evlist__prepare_workload will send a SIGUSR1 if the fork fails, since
+ * we asked by setting its exec_error to the function below,
+ * ftrace__workload_exec_failed_signal.
+ *
+ * XXX We need to handle this more appropriately, emitting an error, etc.
+ */
+static void ftrace__workload_exec_failed_signal(int signo __maybe_unused,
+ siginfo_t *info __maybe_unused,
+ void *ucontext __maybe_unused)
+{
+ /* workload_exec_errno = info->si_value.sival_int; */
+ done = true;
+}
+
+static int __write_tracing_file(const char *name, const char *val, bool append)
+{
+ char *file;
+ int fd, ret = -1;
+ ssize_t size = strlen(val);
+ int flags = O_WRONLY;
+ char errbuf[512];
+ char *val_copy;
+
+ file = get_tracing_file(name);
+ if (!file) {
+ pr_debug("cannot get tracing file: %s\n", name);
+ return -1;
+ }
+
+ if (append)
+ flags |= O_APPEND;
+ else
+ flags |= O_TRUNC;
+
+ fd = open(file, flags);
+ if (fd < 0) {
+ pr_debug("cannot open tracing file: %s: %s\n",
+ name, str_error_r(errno, errbuf, sizeof(errbuf)));
+ goto out;
+ }
+
+ /*
+ * Copy the original value and append a '\n'. Without this,
+ * the kernel can hide possible errors.
+ */
+ val_copy = strdup(val);
+ if (!val_copy)
+ goto out_close;
+ val_copy[size] = '\n';
+
+ if (write(fd, val_copy, size + 1) == size + 1)
+ ret = 0;
+ else
+ pr_debug("write '%s' to tracing/%s failed: %s\n",
+ val, name, str_error_r(errno, errbuf, sizeof(errbuf)));
+
+ free(val_copy);
+out_close:
+ close(fd);
+out:
+ put_tracing_file(file);
+ return ret;
+}
+
+static int write_tracing_file(const char *name, const char *val)
+{
+ return __write_tracing_file(name, val, false);
+}
+
+static int append_tracing_file(const char *name, const char *val)
+{
+ return __write_tracing_file(name, val, true);
+}
+
+static int reset_tracing_cpu(void);
+static void reset_tracing_filters(void);
+
+static int reset_tracing_files(struct perf_ftrace *ftrace __maybe_unused)
+{
+ if (write_tracing_file("tracing_on", "0") < 0)
+ return -1;
+
+ if (write_tracing_file("current_tracer", "nop") < 0)
+ return -1;
+
+ if (write_tracing_file("set_ftrace_pid", " ") < 0)
+ return -1;
+
+ if (reset_tracing_cpu() < 0)
+ return -1;
+
+ if (write_tracing_file("max_graph_depth", "0") < 0)
+ return -1;
+
+ reset_tracing_filters();
+ return 0;
+}
+
+static int set_tracing_pid(struct perf_ftrace *ftrace)
+{
+ int i;
+ char buf[16];
+
+ if (target__has_cpu(&ftrace->target))
+ return 0;
+
+ for (i = 0; i < thread_map__nr(ftrace->evlist->threads); i++) {
+ scnprintf(buf, sizeof(buf), "%d",
+ ftrace->evlist->threads->map[i]);
+ if (append_tracing_file("set_ftrace_pid", buf) < 0)
+ return -1;
+ }
+ return 0;
+}
+
+static int set_tracing_cpumask(struct cpu_map *cpumap)
+{
+ char *cpumask;
+ size_t mask_size;
+ int ret;
+ int last_cpu;
+
+ last_cpu = cpu_map__cpu(cpumap, cpumap->nr - 1);
+ mask_size = (last_cpu + 3) / 4 + 1;
+ mask_size += last_cpu / 32; /* ',' is needed for every 32th cpus */
+
+ cpumask = malloc(mask_size);
+ if (cpumask == NULL) {
+ pr_debug("failed to allocate cpu mask\n");
+ return -1;
+ }
+
+ cpu_map__snprint_mask(cpumap, cpumask, mask_size);
+
+ ret = write_tracing_file("tracing_cpumask", cpumask);
+
+ free(cpumask);
+ return ret;
+}
+
+static int set_tracing_cpu(struct perf_ftrace *ftrace)
+{
+ struct cpu_map *cpumap = ftrace->evlist->cpus;
+
+ if (!target__has_cpu(&ftrace->target))
+ return 0;
+
+ return set_tracing_cpumask(cpumap);
+}
+
+static int reset_tracing_cpu(void)
+{
+ struct cpu_map *cpumap = cpu_map__new(NULL);
+ int ret;
+
+ ret = set_tracing_cpumask(cpumap);
+ cpu_map__put(cpumap);
+ return ret;
+}
+
+static int __set_tracing_filter(const char *filter_file, struct list_head *funcs)
+{
+ struct filter_entry *pos;
+
+ list_for_each_entry(pos, funcs, list) {
+ if (append_tracing_file(filter_file, pos->name) < 0)
+ return -1;
+ }
+
+ return 0;
+}
+
+static int set_tracing_filters(struct perf_ftrace *ftrace)
+{
+ int ret;
+
+ ret = __set_tracing_filter("set_ftrace_filter", &ftrace->filters);
+ if (ret < 0)
+ return ret;
+
+ ret = __set_tracing_filter("set_ftrace_notrace", &ftrace->notrace);
+ if (ret < 0)
+ return ret;
+
+ ret = __set_tracing_filter("set_graph_function", &ftrace->graph_funcs);
+ if (ret < 0)
+ return ret;
+
+ /* old kernels do not have this filter */
+ __set_tracing_filter("set_graph_notrace", &ftrace->nograph_funcs);
+
+ return ret;
+}
+
+static void reset_tracing_filters(void)
+{
+ write_tracing_file("set_ftrace_filter", " ");
+ write_tracing_file("set_ftrace_notrace", " ");
+ write_tracing_file("set_graph_function", " ");
+ write_tracing_file("set_graph_notrace", " ");
+}
+
+static int set_tracing_depth(struct perf_ftrace *ftrace)
+{
+ char buf[16];
+
+ if (ftrace->graph_depth == 0)
+ return 0;
+
+ if (ftrace->graph_depth < 0) {
+ pr_err("invalid graph depth: %d\n", ftrace->graph_depth);
+ return -1;
+ }
+
+ snprintf(buf, sizeof(buf), "%d", ftrace->graph_depth);
+
+ if (write_tracing_file("max_graph_depth", buf) < 0)
+ return -1;
+
+ return 0;
+}
+
+static int __cmd_ftrace(struct perf_ftrace *ftrace, int argc, const char **argv)
+{
+ char *trace_file;
+ int trace_fd;
+ char buf[4096];
+ struct pollfd pollfd = {
+ .events = POLLIN,
+ };
+
+ if (geteuid() != 0) {
+ pr_err("ftrace only works for root!\n");
+ return -1;
+ }
+
+ signal(SIGINT, sig_handler);
+ signal(SIGUSR1, sig_handler);
+ signal(SIGCHLD, sig_handler);
+ signal(SIGPIPE, sig_handler);
+
+ if (reset_tracing_files(ftrace) < 0) {
+ pr_err("failed to reset ftrace\n");
+ goto out;
+ }
+
+ /* reset ftrace buffer */
+ if (write_tracing_file("trace", "0") < 0)
+ goto out;
+
+ if (argc && perf_evlist__prepare_workload(ftrace->evlist,
+ &ftrace->target, argv, false,
+ ftrace__workload_exec_failed_signal) < 0) {
+ goto out;
+ }
+
+ if (set_tracing_pid(ftrace) < 0) {
+ pr_err("failed to set ftrace pid\n");
+ goto out_reset;
+ }
+
+ if (set_tracing_cpu(ftrace) < 0) {
+ pr_err("failed to set tracing cpumask\n");
+ goto out_reset;
+ }
+
+ if (set_tracing_filters(ftrace) < 0) {
+ pr_err("failed to set tracing filters\n");
+ goto out_reset;
+ }
+
+ if (set_tracing_depth(ftrace) < 0) {
+ pr_err("failed to set graph depth\n");
+ goto out_reset;
+ }
+
+ if (write_tracing_file("current_tracer", ftrace->tracer) < 0) {
+ pr_err("failed to set current_tracer to %s\n", ftrace->tracer);
+ goto out_reset;
+ }
+
+ setup_pager();
+
+ trace_file = get_tracing_file("trace_pipe");
+ if (!trace_file) {
+ pr_err("failed to open trace_pipe\n");
+ goto out_reset;
+ }
+
+ trace_fd = open(trace_file, O_RDONLY);
+
+ put_tracing_file(trace_file);
+
+ if (trace_fd < 0) {
+ pr_err("failed to open trace_pipe\n");
+ goto out_reset;
+ }
+
+ fcntl(trace_fd, F_SETFL, O_NONBLOCK);
+ pollfd.fd = trace_fd;
+
+ if (write_tracing_file("tracing_on", "1") < 0) {
+ pr_err("can't enable tracing\n");
+ goto out_close_fd;
+ }
+
+ perf_evlist__start_workload(ftrace->evlist);
+
+ while (!done) {
+ if (poll(&pollfd, 1, -1) < 0)
+ break;
+
+ if (pollfd.revents & POLLIN) {
+ int n = read(trace_fd, buf, sizeof(buf));
+ if (n < 0)
+ break;
+ if (fwrite(buf, n, 1, stdout) != 1)
+ break;
+ }
+ }
+
+ write_tracing_file("tracing_on", "0");
+
+ /* read remaining buffer contents */
+ while (true) {
+ int n = read(trace_fd, buf, sizeof(buf));
+ if (n <= 0)
+ break;
+ if (fwrite(buf, n, 1, stdout) != 1)
+ break;
+ }
+
+out_close_fd:
+ close(trace_fd);
+out_reset:
+ reset_tracing_files(ftrace);
+out:
+ return done ? 0 : -1;
+}
+
+static int perf_ftrace_config(const char *var, const char *value, void *cb)
+{
+ struct perf_ftrace *ftrace = cb;
+
+ if (!strstarts(var, "ftrace."))
+ return 0;
+
+ if (strcmp(var, "ftrace.tracer"))
+ return -1;
+
+ if (!strcmp(value, "function_graph") ||
+ !strcmp(value, "function")) {
+ ftrace->tracer = value;
+ return 0;
+ }
+
+ pr_err("Please select \"function_graph\" (default) or \"function\"\n");
+ return -1;
+}
+
+static int parse_filter_func(const struct option *opt, const char *str,
+ int unset __maybe_unused)
+{
+ struct list_head *head = opt->value;
+ struct filter_entry *entry;
+
+ entry = malloc(sizeof(*entry) + strlen(str) + 1);
+ if (entry == NULL)
+ return -ENOMEM;
+
+ strcpy(entry->name, str);
+ list_add_tail(&entry->list, head);
+
+ return 0;
+}
+
+static void delete_filter_func(struct list_head *head)
+{
+ struct filter_entry *pos, *tmp;
+
+ list_for_each_entry_safe(pos, tmp, head, list) {
+ list_del(&pos->list);
+ free(pos);
+ }
+}
+
+int cmd_ftrace(int argc, const char **argv)
+{
+ int ret;
+ struct perf_ftrace ftrace = {
+ .tracer = DEFAULT_TRACER,
+ .target = { .uid = UINT_MAX, },
+ };
+ const char * const ftrace_usage[] = {
+ "perf ftrace [<options>] [<command>]",
+ "perf ftrace [<options>] -- <command> [<options>]",
+ NULL
+ };
+ const struct option ftrace_options[] = {
+ OPT_STRING('t', "tracer", &ftrace.tracer, "tracer",
+ "tracer to use: function_graph(default) or function"),
+ OPT_STRING('p', "pid", &ftrace.target.pid, "pid",
+ "trace on existing process id"),
+ OPT_INCR('v', "verbose", &verbose,
+ "be more verbose"),
+ OPT_BOOLEAN('a', "all-cpus", &ftrace.target.system_wide,
+ "system-wide collection from all CPUs"),
+ OPT_STRING('C', "cpu", &ftrace.target.cpu_list, "cpu",
+ "list of cpus to monitor"),
+ OPT_CALLBACK('T', "trace-funcs", &ftrace.filters, "func",
+ "trace given functions only", parse_filter_func),
+ OPT_CALLBACK('N', "notrace-funcs", &ftrace.notrace, "func",
+ "do not trace given functions", parse_filter_func),
+ OPT_CALLBACK('G', "graph-funcs", &ftrace.graph_funcs, "func",
+ "Set graph filter on given functions", parse_filter_func),
+ OPT_CALLBACK('g', "nograph-funcs", &ftrace.nograph_funcs, "func",
+ "Set nograph filter on given functions", parse_filter_func),
+ OPT_INTEGER('D', "graph-depth", &ftrace.graph_depth,
+ "Max depth for function graph tracer"),
+ OPT_END()
+ };
+
+ INIT_LIST_HEAD(&ftrace.filters);
+ INIT_LIST_HEAD(&ftrace.notrace);
+ INIT_LIST_HEAD(&ftrace.graph_funcs);
+ INIT_LIST_HEAD(&ftrace.nograph_funcs);
+
+ ret = perf_config(perf_ftrace_config, &ftrace);
+ if (ret < 0)
+ return -1;
+
+ argc = parse_options(argc, argv, ftrace_options, ftrace_usage,
+ PARSE_OPT_STOP_AT_NON_OPTION);
+ if (!argc && target__none(&ftrace.target))
+ usage_with_options(ftrace_usage, ftrace_options);
+
+ ret = target__validate(&ftrace.target);
+ if (ret) {
+ char errbuf[512];
+
+ target__strerror(&ftrace.target, ret, errbuf, 512);
+ pr_err("%s\n", errbuf);
+ goto out_delete_filters;
+ }
+
+ ftrace.evlist = perf_evlist__new();
+ if (ftrace.evlist == NULL) {
+ ret = -ENOMEM;
+ goto out_delete_filters;
+ }
+
+ ret = perf_evlist__create_maps(ftrace.evlist, &ftrace.target);
+ if (ret < 0)
+ goto out_delete_evlist;
+
+ ret = __cmd_ftrace(&ftrace, argc, argv);
+
+out_delete_evlist:
+ perf_evlist__delete(ftrace.evlist);
+
+out_delete_filters:
+ delete_filter_func(&ftrace.filters);
+ delete_filter_func(&ftrace.notrace);
+ delete_filter_func(&ftrace.graph_funcs);
+ delete_filter_func(&ftrace.nograph_funcs);
+
+ return ret;
+}