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-rw-r--r--tools/perf/builtin-ftrace.c1294
1 files changed, 1294 insertions, 0 deletions
diff --git a/tools/perf/builtin-ftrace.c b/tools/perf/builtin-ftrace.c
new file mode 100644
index 000000000..1d40f9bcb
--- /dev/null
+++ b/tools/perf/builtin-ftrace.c
@@ -0,0 +1,1294 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * builtin-ftrace.c
+ *
+ * Copyright (c) 2013 LG Electronics, Namhyung Kim <namhyung@kernel.org>
+ * Copyright (c) 2020 Changbin Du <changbin.du@gmail.com>, significant enhancement.
+ */
+
+#include "builtin.h"
+
+#include <errno.h>
+#include <unistd.h>
+#include <signal.h>
+#include <stdlib.h>
+#include <fcntl.h>
+#include <math.h>
+#include <poll.h>
+#include <ctype.h>
+#include <linux/capability.h>
+#include <linux/string.h>
+
+#include "debug.h"
+#include <subcmd/pager.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 "strfilter.h"
+#include "util/cap.h"
+#include "util/config.h"
+#include "util/ftrace.h"
+#include "util/units.h"
+#include "util/parse-sublevel-options.h"
+
+#define DEFAULT_TRACER "function_graph"
+
+static volatile int workload_exec_errno;
+static bool done;
+
+static void sig_handler(int sig __maybe_unused)
+{
+ done = true;
+}
+
+/*
+ * 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 read_tracing_file_to_stdout(const char *name)
+{
+ char buf[4096];
+ char *file;
+ int fd;
+ int ret = -1;
+
+ file = get_tracing_file(name);
+ if (!file) {
+ pr_debug("cannot get tracing file: %s\n", name);
+ return -1;
+ }
+
+ fd = open(file, O_RDONLY);
+ if (fd < 0) {
+ pr_debug("cannot open tracing file: %s: %s\n",
+ name, str_error_r(errno, buf, sizeof(buf)));
+ goto out;
+ }
+
+ /* read contents to stdout */
+ while (true) {
+ int n = read(fd, buf, sizeof(buf));
+ if (n == 0)
+ break;
+ else if (n < 0)
+ goto out_close;
+
+ if (fwrite(buf, n, 1, stdout) != 1)
+ goto out_close;
+ }
+ ret = 0;
+
+out_close:
+ close(fd);
+out:
+ put_tracing_file(file);
+ return ret;
+}
+
+static int read_tracing_file_by_line(const char *name,
+ void (*cb)(char *str, void *arg),
+ void *cb_arg)
+{
+ char *line = NULL;
+ size_t len = 0;
+ char *file;
+ FILE *fp;
+
+ file = get_tracing_file(name);
+ if (!file) {
+ pr_debug("cannot get tracing file: %s\n", name);
+ return -1;
+ }
+
+ fp = fopen(file, "r");
+ if (fp == NULL) {
+ pr_debug("cannot open tracing file: %s\n", name);
+ put_tracing_file(file);
+ return -1;
+ }
+
+ while (getline(&line, &len, fp) != -1) {
+ cb(line, cb_arg);
+ }
+
+ if (line)
+ free(line);
+
+ fclose(fp);
+ put_tracing_file(file);
+ return 0;
+}
+
+static int write_tracing_file_int(const char *name, int value)
+{
+ char buf[16];
+
+ snprintf(buf, sizeof(buf), "%d", value);
+ if (write_tracing_file(name, buf) < 0)
+ return -1;
+
+ return 0;
+}
+
+static int write_tracing_option_file(const char *name, const char *val)
+{
+ char *file;
+ int ret;
+
+ if (asprintf(&file, "options/%s", name) < 0)
+ return -1;
+
+ ret = __write_tracing_file(file, val, false);
+ free(file);
+ return ret;
+}
+
+static int reset_tracing_cpu(void);
+static void reset_tracing_filters(void);
+
+static void reset_tracing_options(struct perf_ftrace *ftrace __maybe_unused)
+{
+ write_tracing_option_file("function-fork", "0");
+ write_tracing_option_file("func_stack_trace", "0");
+ write_tracing_option_file("sleep-time", "1");
+ write_tracing_option_file("funcgraph-irqs", "1");
+ write_tracing_option_file("funcgraph-proc", "0");
+ write_tracing_option_file("funcgraph-abstime", "0");
+ write_tracing_option_file("latency-format", "0");
+ write_tracing_option_file("irq-info", "0");
+}
+
+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;
+
+ if (write_tracing_file("tracing_thresh", "0") < 0)
+ return -1;
+
+ reset_tracing_filters();
+ reset_tracing_options(ftrace);
+ 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 < perf_thread_map__nr(ftrace->evlist->core.threads); i++) {
+ scnprintf(buf, sizeof(buf), "%d",
+ perf_thread_map__pid(ftrace->evlist->core.threads, i));
+ if (append_tracing_file("set_ftrace_pid", buf) < 0)
+ return -1;
+ }
+ return 0;
+}
+
+static int set_tracing_cpumask(struct perf_cpu_map *cpumap)
+{
+ char *cpumask;
+ size_t mask_size;
+ int ret;
+ int last_cpu;
+
+ last_cpu = perf_cpu_map__cpu(cpumap, perf_cpu_map__nr(cpumap) - 1).cpu;
+ mask_size = last_cpu / 4 + 2; /* one more byte for EOS */
+ 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 perf_cpu_map *cpumap = ftrace->evlist->core.user_requested_cpus;
+
+ if (!target__has_cpu(&ftrace->target))
+ return 0;
+
+ return set_tracing_cpumask(cpumap);
+}
+
+static int set_tracing_func_stack_trace(struct perf_ftrace *ftrace)
+{
+ if (!ftrace->func_stack_trace)
+ return 0;
+
+ if (write_tracing_option_file("func_stack_trace", "1") < 0)
+ return -1;
+
+ return 0;
+}
+
+static int set_tracing_func_irqinfo(struct perf_ftrace *ftrace)
+{
+ if (!ftrace->func_irq_info)
+ return 0;
+
+ if (write_tracing_option_file("irq-info", "1") < 0)
+ return -1;
+
+ return 0;
+}
+
+static int reset_tracing_cpu(void)
+{
+ struct perf_cpu_map *cpumap = perf_cpu_map__new(NULL);
+ int ret;
+
+ ret = set_tracing_cpumask(cpumap);
+ perf_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)
+{
+ if (ftrace->graph_depth == 0)
+ return 0;
+
+ if (ftrace->graph_depth < 0) {
+ pr_err("invalid graph depth: %d\n", ftrace->graph_depth);
+ return -1;
+ }
+
+ if (write_tracing_file_int("max_graph_depth", ftrace->graph_depth) < 0)
+ return -1;
+
+ return 0;
+}
+
+static int set_tracing_percpu_buffer_size(struct perf_ftrace *ftrace)
+{
+ int ret;
+
+ if (ftrace->percpu_buffer_size == 0)
+ return 0;
+
+ ret = write_tracing_file_int("buffer_size_kb",
+ ftrace->percpu_buffer_size / 1024);
+ if (ret < 0)
+ return ret;
+
+ return 0;
+}
+
+static int set_tracing_trace_inherit(struct perf_ftrace *ftrace)
+{
+ if (!ftrace->inherit)
+ return 0;
+
+ if (write_tracing_option_file("function-fork", "1") < 0)
+ return -1;
+
+ return 0;
+}
+
+static int set_tracing_sleep_time(struct perf_ftrace *ftrace)
+{
+ if (!ftrace->graph_nosleep_time)
+ return 0;
+
+ if (write_tracing_option_file("sleep-time", "0") < 0)
+ return -1;
+
+ return 0;
+}
+
+static int set_tracing_funcgraph_irqs(struct perf_ftrace *ftrace)
+{
+ if (!ftrace->graph_noirqs)
+ return 0;
+
+ if (write_tracing_option_file("funcgraph-irqs", "0") < 0)
+ return -1;
+
+ return 0;
+}
+
+static int set_tracing_funcgraph_verbose(struct perf_ftrace *ftrace)
+{
+ if (!ftrace->graph_verbose)
+ return 0;
+
+ if (write_tracing_option_file("funcgraph-proc", "1") < 0)
+ return -1;
+
+ if (write_tracing_option_file("funcgraph-abstime", "1") < 0)
+ return -1;
+
+ if (write_tracing_option_file("latency-format", "1") < 0)
+ return -1;
+
+ return 0;
+}
+
+static int set_tracing_thresh(struct perf_ftrace *ftrace)
+{
+ int ret;
+
+ if (ftrace->graph_thresh == 0)
+ return 0;
+
+ ret = write_tracing_file_int("tracing_thresh", ftrace->graph_thresh);
+ if (ret < 0)
+ return ret;
+
+ return 0;
+}
+
+static int set_tracing_options(struct perf_ftrace *ftrace)
+{
+ if (set_tracing_pid(ftrace) < 0) {
+ pr_err("failed to set ftrace pid\n");
+ return -1;
+ }
+
+ if (set_tracing_cpu(ftrace) < 0) {
+ pr_err("failed to set tracing cpumask\n");
+ return -1;
+ }
+
+ if (set_tracing_func_stack_trace(ftrace) < 0) {
+ pr_err("failed to set tracing option func_stack_trace\n");
+ return -1;
+ }
+
+ if (set_tracing_func_irqinfo(ftrace) < 0) {
+ pr_err("failed to set tracing option irq-info\n");
+ return -1;
+ }
+
+ if (set_tracing_filters(ftrace) < 0) {
+ pr_err("failed to set tracing filters\n");
+ return -1;
+ }
+
+ if (set_tracing_depth(ftrace) < 0) {
+ pr_err("failed to set graph depth\n");
+ return -1;
+ }
+
+ if (set_tracing_percpu_buffer_size(ftrace) < 0) {
+ pr_err("failed to set tracing per-cpu buffer size\n");
+ return -1;
+ }
+
+ if (set_tracing_trace_inherit(ftrace) < 0) {
+ pr_err("failed to set tracing option function-fork\n");
+ return -1;
+ }
+
+ if (set_tracing_sleep_time(ftrace) < 0) {
+ pr_err("failed to set tracing option sleep-time\n");
+ return -1;
+ }
+
+ if (set_tracing_funcgraph_irqs(ftrace) < 0) {
+ pr_err("failed to set tracing option funcgraph-irqs\n");
+ return -1;
+ }
+
+ if (set_tracing_funcgraph_verbose(ftrace) < 0) {
+ pr_err("failed to set tracing option funcgraph-proc/funcgraph-abstime\n");
+ return -1;
+ }
+
+ if (set_tracing_thresh(ftrace) < 0) {
+ pr_err("failed to set tracing thresh\n");
+ return -1;
+ }
+
+ return 0;
+}
+
+static void select_tracer(struct perf_ftrace *ftrace)
+{
+ bool graph = !list_empty(&ftrace->graph_funcs) ||
+ !list_empty(&ftrace->nograph_funcs);
+ bool func = !list_empty(&ftrace->filters) ||
+ !list_empty(&ftrace->notrace);
+
+ /* The function_graph has priority over function tracer. */
+ if (graph)
+ ftrace->tracer = "function_graph";
+ else if (func)
+ ftrace->tracer = "function";
+ /* Otherwise, the default tracer is used. */
+
+ pr_debug("%s tracer is used\n", ftrace->tracer);
+}
+
+static int __cmd_ftrace(struct perf_ftrace *ftrace)
+{
+ char *trace_file;
+ int trace_fd;
+ char buf[4096];
+ struct pollfd pollfd = {
+ .events = POLLIN,
+ };
+
+ if (!(perf_cap__capable(CAP_PERFMON) ||
+ perf_cap__capable(CAP_SYS_ADMIN))) {
+ pr_err("ftrace only works for %s!\n",
+#ifdef HAVE_LIBCAP_SUPPORT
+ "users with the CAP_PERFMON or CAP_SYS_ADMIN capability"
+#else
+ "root"
+#endif
+ );
+ return -1;
+ }
+
+ select_tracer(ftrace);
+
+ 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 (set_tracing_options(ftrace) < 0)
+ 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;
+
+ /* display column headers */
+ read_tracing_file_to_stdout("trace");
+
+ if (!ftrace->initial_delay) {
+ if (write_tracing_file("tracing_on", "1") < 0) {
+ pr_err("can't enable tracing\n");
+ goto out_close_fd;
+ }
+ }
+
+ evlist__start_workload(ftrace->evlist);
+
+ if (ftrace->initial_delay) {
+ usleep(ftrace->initial_delay * 1000);
+ if (write_tracing_file("tracing_on", "1") < 0) {
+ pr_err("can't enable tracing\n");
+ goto out_close_fd;
+ }
+ }
+
+ 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");
+
+ if (workload_exec_errno) {
+ const char *emsg = str_error_r(workload_exec_errno, buf, sizeof(buf));
+ /* flush stdout first so below error msg appears at the end. */
+ fflush(stdout);
+ pr_err("workload failed: %s\n", emsg);
+ goto out_close_fd;
+ }
+
+ /* 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 && !workload_exec_errno) ? 0 : -1;
+}
+
+static void make_histogram(int buckets[], char *buf, size_t len, char *linebuf,
+ bool use_nsec)
+{
+ char *p, *q;
+ char *unit;
+ double num;
+ int i;
+
+ /* ensure NUL termination */
+ buf[len] = '\0';
+
+ /* handle data line by line */
+ for (p = buf; (q = strchr(p, '\n')) != NULL; p = q + 1) {
+ *q = '\0';
+ /* move it to the line buffer */
+ strcat(linebuf, p);
+
+ /*
+ * parse trace output to get function duration like in
+ *
+ * # tracer: function_graph
+ * #
+ * # CPU DURATION FUNCTION CALLS
+ * # | | | | | | |
+ * 1) + 10.291 us | do_filp_open();
+ * 1) 4.889 us | do_filp_open();
+ * 1) 6.086 us | do_filp_open();
+ *
+ */
+ if (linebuf[0] == '#')
+ goto next;
+
+ /* ignore CPU */
+ p = strchr(linebuf, ')');
+ if (p == NULL)
+ p = linebuf;
+
+ while (*p && !isdigit(*p) && (*p != '|'))
+ p++;
+
+ /* no duration */
+ if (*p == '\0' || *p == '|')
+ goto next;
+
+ num = strtod(p, &unit);
+ if (!unit || strncmp(unit, " us", 3))
+ goto next;
+
+ if (use_nsec)
+ num *= 1000;
+
+ i = log2(num);
+ if (i < 0)
+ i = 0;
+ if (i >= NUM_BUCKET)
+ i = NUM_BUCKET - 1;
+
+ buckets[i]++;
+
+next:
+ /* empty the line buffer for the next output */
+ linebuf[0] = '\0';
+ }
+
+ /* preserve any remaining output (before newline) */
+ strcat(linebuf, p);
+}
+
+static void display_histogram(int buckets[], bool use_nsec)
+{
+ int i;
+ int total = 0;
+ int bar_total = 46; /* to fit in 80 column */
+ char bar[] = "###############################################";
+ int bar_len;
+
+ for (i = 0; i < NUM_BUCKET; i++)
+ total += buckets[i];
+
+ if (total == 0) {
+ printf("No data found\n");
+ return;
+ }
+
+ printf("# %14s | %10s | %-*s |\n",
+ " DURATION ", "COUNT", bar_total, "GRAPH");
+
+ bar_len = buckets[0] * bar_total / total;
+ printf(" %4d - %-4d %s | %10d | %.*s%*s |\n",
+ 0, 1, "us", buckets[0], bar_len, bar, bar_total - bar_len, "");
+
+ for (i = 1; i < NUM_BUCKET - 1; i++) {
+ int start = (1 << (i - 1));
+ int stop = 1 << i;
+ const char *unit = use_nsec ? "ns" : "us";
+
+ if (start >= 1024) {
+ start >>= 10;
+ stop >>= 10;
+ unit = use_nsec ? "us" : "ms";
+ }
+ bar_len = buckets[i] * bar_total / total;
+ printf(" %4d - %-4d %s | %10d | %.*s%*s |\n",
+ start, stop, unit, buckets[i], bar_len, bar,
+ bar_total - bar_len, "");
+ }
+
+ bar_len = buckets[NUM_BUCKET - 1] * bar_total / total;
+ printf(" %4d - %-4s %s | %10d | %.*s%*s |\n",
+ 1, "...", use_nsec ? "ms" : " s", buckets[NUM_BUCKET - 1],
+ bar_len, bar, bar_total - bar_len, "");
+
+}
+
+static int prepare_func_latency(struct perf_ftrace *ftrace)
+{
+ char *trace_file;
+ int fd;
+
+ if (ftrace->target.use_bpf)
+ return perf_ftrace__latency_prepare_bpf(ftrace);
+
+ if (reset_tracing_files(ftrace) < 0) {
+ pr_err("failed to reset ftrace\n");
+ return -1;
+ }
+
+ /* reset ftrace buffer */
+ if (write_tracing_file("trace", "0") < 0)
+ return -1;
+
+ if (set_tracing_options(ftrace) < 0)
+ return -1;
+
+ /* force to use the function_graph tracer to track duration */
+ if (write_tracing_file("current_tracer", "function_graph") < 0) {
+ pr_err("failed to set current_tracer to function_graph\n");
+ return -1;
+ }
+
+ trace_file = get_tracing_file("trace_pipe");
+ if (!trace_file) {
+ pr_err("failed to open trace_pipe\n");
+ return -1;
+ }
+
+ fd = open(trace_file, O_RDONLY);
+ if (fd < 0)
+ pr_err("failed to open trace_pipe\n");
+
+ put_tracing_file(trace_file);
+ return fd;
+}
+
+static int start_func_latency(struct perf_ftrace *ftrace)
+{
+ if (ftrace->target.use_bpf)
+ return perf_ftrace__latency_start_bpf(ftrace);
+
+ if (write_tracing_file("tracing_on", "1") < 0) {
+ pr_err("can't enable tracing\n");
+ return -1;
+ }
+
+ return 0;
+}
+
+static int stop_func_latency(struct perf_ftrace *ftrace)
+{
+ if (ftrace->target.use_bpf)
+ return perf_ftrace__latency_stop_bpf(ftrace);
+
+ write_tracing_file("tracing_on", "0");
+ return 0;
+}
+
+static int read_func_latency(struct perf_ftrace *ftrace, int buckets[])
+{
+ if (ftrace->target.use_bpf)
+ return perf_ftrace__latency_read_bpf(ftrace, buckets);
+
+ return 0;
+}
+
+static int cleanup_func_latency(struct perf_ftrace *ftrace)
+{
+ if (ftrace->target.use_bpf)
+ return perf_ftrace__latency_cleanup_bpf(ftrace);
+
+ reset_tracing_files(ftrace);
+ return 0;
+}
+
+static int __cmd_latency(struct perf_ftrace *ftrace)
+{
+ int trace_fd;
+ char buf[4096];
+ char line[256];
+ struct pollfd pollfd = {
+ .events = POLLIN,
+ };
+ int buckets[NUM_BUCKET] = { };
+
+ if (!(perf_cap__capable(CAP_PERFMON) ||
+ perf_cap__capable(CAP_SYS_ADMIN))) {
+ pr_err("ftrace only works for %s!\n",
+#ifdef HAVE_LIBCAP_SUPPORT
+ "users with the CAP_PERFMON or CAP_SYS_ADMIN capability"
+#else
+ "root"
+#endif
+ );
+ return -1;
+ }
+
+ trace_fd = prepare_func_latency(ftrace);
+ if (trace_fd < 0)
+ goto out;
+
+ fcntl(trace_fd, F_SETFL, O_NONBLOCK);
+ pollfd.fd = trace_fd;
+
+ if (start_func_latency(ftrace) < 0)
+ goto out;
+
+ evlist__start_workload(ftrace->evlist);
+
+ line[0] = '\0';
+ while (!done) {
+ if (poll(&pollfd, 1, -1) < 0)
+ break;
+
+ if (pollfd.revents & POLLIN) {
+ int n = read(trace_fd, buf, sizeof(buf) - 1);
+ if (n < 0)
+ break;
+
+ make_histogram(buckets, buf, n, line, ftrace->use_nsec);
+ }
+ }
+
+ stop_func_latency(ftrace);
+
+ if (workload_exec_errno) {
+ const char *emsg = str_error_r(workload_exec_errno, buf, sizeof(buf));
+ pr_err("workload failed: %s\n", emsg);
+ goto out;
+ }
+
+ /* read remaining buffer contents */
+ while (!ftrace->target.use_bpf) {
+ int n = read(trace_fd, buf, sizeof(buf) - 1);
+ if (n <= 0)
+ break;
+ make_histogram(buckets, buf, n, line, ftrace->use_nsec);
+ }
+
+ read_func_latency(ftrace, buckets);
+
+ display_histogram(buckets, ftrace->use_nsec);
+
+out:
+ close(trace_fd);
+ cleanup_func_latency(ftrace);
+
+ return (done && !workload_exec_errno) ? 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 void list_function_cb(char *str, void *arg)
+{
+ struct strfilter *filter = (struct strfilter *)arg;
+
+ if (strfilter__compare(filter, str))
+ printf("%s", str);
+}
+
+static int opt_list_avail_functions(const struct option *opt __maybe_unused,
+ const char *str, int unset)
+{
+ struct strfilter *filter;
+ const char *err = NULL;
+ int ret;
+
+ if (unset || !str)
+ return -1;
+
+ filter = strfilter__new(str, &err);
+ if (!filter)
+ return err ? -EINVAL : -ENOMEM;
+
+ ret = strfilter__or(filter, str, &err);
+ if (ret == -EINVAL) {
+ pr_err("Filter parse error at %td.\n", err - str + 1);
+ pr_err("Source: \"%s\"\n", str);
+ pr_err(" %*c\n", (int)(err - str + 1), '^');
+ strfilter__delete(filter);
+ return ret;
+ }
+
+ ret = read_tracing_file_by_line("available_filter_functions",
+ list_function_cb, filter);
+ strfilter__delete(filter);
+ if (ret < 0)
+ return ret;
+
+ exit(0);
+}
+
+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_init(&pos->list);
+ free(pos);
+ }
+}
+
+static int parse_buffer_size(const struct option *opt,
+ const char *str, int unset)
+{
+ unsigned long *s = (unsigned long *)opt->value;
+ static struct parse_tag tags_size[] = {
+ { .tag = 'B', .mult = 1 },
+ { .tag = 'K', .mult = 1 << 10 },
+ { .tag = 'M', .mult = 1 << 20 },
+ { .tag = 'G', .mult = 1 << 30 },
+ { .tag = 0 },
+ };
+ unsigned long val;
+
+ if (unset) {
+ *s = 0;
+ return 0;
+ }
+
+ val = parse_tag_value(str, tags_size);
+ if (val != (unsigned long) -1) {
+ if (val < 1024) {
+ pr_err("buffer size too small, must larger than 1KB.");
+ return -1;
+ }
+ *s = val;
+ return 0;
+ }
+
+ return -1;
+}
+
+static int parse_func_tracer_opts(const struct option *opt,
+ const char *str, int unset)
+{
+ int ret;
+ struct perf_ftrace *ftrace = (struct perf_ftrace *) opt->value;
+ struct sublevel_option func_tracer_opts[] = {
+ { .name = "call-graph", .value_ptr = &ftrace->func_stack_trace },
+ { .name = "irq-info", .value_ptr = &ftrace->func_irq_info },
+ { .name = NULL, }
+ };
+
+ if (unset)
+ return 0;
+
+ ret = perf_parse_sublevel_options(str, func_tracer_opts);
+ if (ret)
+ return ret;
+
+ return 0;
+}
+
+static int parse_graph_tracer_opts(const struct option *opt,
+ const char *str, int unset)
+{
+ int ret;
+ struct perf_ftrace *ftrace = (struct perf_ftrace *) opt->value;
+ struct sublevel_option graph_tracer_opts[] = {
+ { .name = "nosleep-time", .value_ptr = &ftrace->graph_nosleep_time },
+ { .name = "noirqs", .value_ptr = &ftrace->graph_noirqs },
+ { .name = "verbose", .value_ptr = &ftrace->graph_verbose },
+ { .name = "thresh", .value_ptr = &ftrace->graph_thresh },
+ { .name = "depth", .value_ptr = &ftrace->graph_depth },
+ { .name = NULL, }
+ };
+
+ if (unset)
+ return 0;
+
+ ret = perf_parse_sublevel_options(str, graph_tracer_opts);
+ if (ret)
+ return ret;
+
+ return 0;
+}
+
+enum perf_ftrace_subcommand {
+ PERF_FTRACE_NONE,
+ PERF_FTRACE_TRACE,
+ PERF_FTRACE_LATENCY,
+};
+
+int cmd_ftrace(int argc, const char **argv)
+{
+ int ret;
+ int (*cmd_func)(struct perf_ftrace *) = NULL;
+ struct perf_ftrace ftrace = {
+ .tracer = DEFAULT_TRACER,
+ .target = { .uid = UINT_MAX, },
+ };
+ const struct option common_options[] = {
+ OPT_STRING('p', "pid", &ftrace.target.pid, "pid",
+ "Trace on existing process id"),
+ /* TODO: Add short option -t after -t/--tracer can be removed. */
+ OPT_STRING(0, "tid", &ftrace.target.tid, "tid",
+ "Trace on existing thread id (exclusive to --pid)"),
+ 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_END()
+ };
+ const struct option ftrace_options[] = {
+ OPT_STRING('t', "tracer", &ftrace.tracer, "tracer",
+ "Tracer to use: function_graph(default) or function"),
+ OPT_CALLBACK_DEFAULT('F', "funcs", NULL, "[FILTER]",
+ "Show available functions to filter",
+ opt_list_avail_functions, "*"),
+ OPT_CALLBACK('T', "trace-funcs", &ftrace.filters, "func",
+ "Trace given functions using function tracer",
+ parse_filter_func),
+ OPT_CALLBACK('N', "notrace-funcs", &ftrace.notrace, "func",
+ "Do not trace given functions", parse_filter_func),
+ OPT_CALLBACK(0, "func-opts", &ftrace, "options",
+ "Function tracer options, available options: call-graph,irq-info",
+ parse_func_tracer_opts),
+ OPT_CALLBACK('G', "graph-funcs", &ftrace.graph_funcs, "func",
+ "Trace given functions using function_graph tracer",
+ parse_filter_func),
+ OPT_CALLBACK('g', "nograph-funcs", &ftrace.nograph_funcs, "func",
+ "Set nograph filter on given functions", parse_filter_func),
+ OPT_CALLBACK(0, "graph-opts", &ftrace, "options",
+ "Graph tracer options, available options: nosleep-time,noirqs,verbose,thresh=<n>,depth=<n>",
+ parse_graph_tracer_opts),
+ OPT_CALLBACK('m', "buffer-size", &ftrace.percpu_buffer_size, "size",
+ "Size of per cpu buffer, needs to use a B, K, M or G suffix.", parse_buffer_size),
+ OPT_BOOLEAN(0, "inherit", &ftrace.inherit,
+ "Trace children processes"),
+ OPT_UINTEGER('D', "delay", &ftrace.initial_delay,
+ "Number of milliseconds to wait before starting tracing after program start"),
+ OPT_PARENT(common_options),
+ };
+ const struct option latency_options[] = {
+ OPT_CALLBACK('T', "trace-funcs", &ftrace.filters, "func",
+ "Show latency of given function", parse_filter_func),
+#ifdef HAVE_BPF_SKEL
+ OPT_BOOLEAN('b', "use-bpf", &ftrace.target.use_bpf,
+ "Use BPF to measure function latency"),
+#endif
+ OPT_BOOLEAN('n', "use-nsec", &ftrace.use_nsec,
+ "Use nano-second histogram"),
+ OPT_PARENT(common_options),
+ };
+ const struct option *options = ftrace_options;
+
+ const char * const ftrace_usage[] = {
+ "perf ftrace [<options>] [<command>]",
+ "perf ftrace [<options>] -- [<command>] [<options>]",
+ "perf ftrace {trace|latency} [<options>] [<command>]",
+ "perf ftrace {trace|latency} [<options>] -- [<command>] [<options>]",
+ NULL
+ };
+ enum perf_ftrace_subcommand subcmd = PERF_FTRACE_NONE;
+
+ INIT_LIST_HEAD(&ftrace.filters);
+ INIT_LIST_HEAD(&ftrace.notrace);
+ INIT_LIST_HEAD(&ftrace.graph_funcs);
+ INIT_LIST_HEAD(&ftrace.nograph_funcs);
+
+ signal(SIGINT, sig_handler);
+ signal(SIGUSR1, sig_handler);
+ signal(SIGCHLD, sig_handler);
+ signal(SIGPIPE, sig_handler);
+
+ ret = perf_config(perf_ftrace_config, &ftrace);
+ if (ret < 0)
+ return -1;
+
+ if (argc > 1) {
+ if (!strcmp(argv[1], "trace")) {
+ subcmd = PERF_FTRACE_TRACE;
+ } else if (!strcmp(argv[1], "latency")) {
+ subcmd = PERF_FTRACE_LATENCY;
+ options = latency_options;
+ }
+
+ if (subcmd != PERF_FTRACE_NONE) {
+ argc--;
+ argv++;
+ }
+ }
+ /* for backward compatibility */
+ if (subcmd == PERF_FTRACE_NONE)
+ subcmd = PERF_FTRACE_TRACE;
+
+ argc = parse_options(argc, argv, options, ftrace_usage,
+ PARSE_OPT_STOP_AT_NON_OPTION);
+ if (argc < 0) {
+ ret = -EINVAL;
+ goto out_delete_filters;
+ }
+
+ /* Make system wide (-a) the default target. */
+ if (!argc && target__none(&ftrace.target))
+ ftrace.target.system_wide = true;
+
+ switch (subcmd) {
+ case PERF_FTRACE_TRACE:
+ cmd_func = __cmd_ftrace;
+ break;
+ case PERF_FTRACE_LATENCY:
+ if (list_empty(&ftrace.filters)) {
+ pr_err("Should provide a function to measure\n");
+ parse_options_usage(ftrace_usage, options, "T", 1);
+ ret = -EINVAL;
+ goto out_delete_filters;
+ }
+ cmd_func = __cmd_latency;
+ break;
+ case PERF_FTRACE_NONE:
+ default:
+ pr_err("Invalid subcommand\n");
+ ret = -EINVAL;
+ goto out_delete_filters;
+ }
+
+ 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 = evlist__new();
+ if (ftrace.evlist == NULL) {
+ ret = -ENOMEM;
+ goto out_delete_filters;
+ }
+
+ ret = evlist__create_maps(ftrace.evlist, &ftrace.target);
+ if (ret < 0)
+ goto out_delete_evlist;
+
+ if (argc) {
+ ret = evlist__prepare_workload(ftrace.evlist, &ftrace.target,
+ argv, false,
+ ftrace__workload_exec_failed_signal);
+ if (ret < 0)
+ goto out_delete_evlist;
+ }
+
+ ret = cmd_func(&ftrace);
+
+out_delete_evlist:
+ 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;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-22 16:39:34 +0000