From d01f4e8db22cf4d04f6c86351d959b584eb1f5f7 Mon Sep 17 00:00:00 2001 From: Namhyung Kim Date: Thu, 7 Mar 2013 21:45:20 +0900 Subject: [PATCH] perf ftrace: Introduce new 'ftrace' tool The 'perf ftrace' command is a simple wrapper of kernel's ftrace functionality. It only supports single thread tracing currently and just reads trace_pipe in text and then write it to stdout. Committer notes: Testing it: # perf ftrace -f function_graph usleep 123456 2) | SyS_nanosleep() { 2) | _copy_from_user() { 2) 0.900 us | } 2) 1.354 us | } 2) | hrtimer_nanosleep() { 2) 0.062 us | __hrtimer_init(); 2) | do_nanosleep() { 2) | hrtimer_start_range_ns() { 2) 5.025 us | } 2) | schedule() { 2) 0.125 us | rcu_note_context_switch(); 2) 0.057 us | _raw_spin_lock(); 2) | deactivate_task() { 2) 0.369 us | update_rq_clock.part.77(); 2) | dequeue_task_fair() { 2) + 22.453 us | } 2) + 23.736 us | } 2) | pick_next_task_fair() { 2) + 47.167 us | } 2) | pick_next_task_idle() { 2) 4.462 us | } ------------------------------------------ 2) usleep-20387 => -0 ------------------------------------------ 2) 0.806 us | switch_mm_irqs_off(); ------------------------------------------ 2) -0 => usleep-20387 ------------------------------------------ 2) 0.151 us | finish_task_switch(); 2) @ 123597.2 us | } 2) 0.037 us | _cond_resched(); 2) | hrtimer_try_to_cancel() { 2) 0.064 us | hrtimer_active(); 2) 0.353 us | } 2) @ 123605.3 us | } 2) @ 123606.2 us | } 2) @ 123608.3 us | } /* SyS_nanosleep */ 2) | __do_page_fault() { Signed-off-by: Namhyung Kim Tested-by: Arnaldo Carvalho de Melo Tested-by: Masami Hiramatsu Cc: Frederic Weisbecker Cc: Jeremy Eder Cc: Jiri Olsa , Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Stephane Eranian Cc: Steven Rostedt Link: http://lkml.kernel.org/n/tip-r1hgmsj4dxny8arn3o9mw512@git.kernel.org [ Various foward port fixes, add man page ] Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/Build | 1 + tools/perf/Documentation/perf-ftrace.txt | 36 ++++ tools/perf/builtin-ftrace.c | 242 +++++++++++++++++++++++ tools/perf/builtin.h | 1 + tools/perf/command-list.txt | 1 + tools/perf/perf.c | 1 + 6 files changed, 282 insertions(+) create mode 100644 tools/perf/Documentation/perf-ftrace.txt create mode 100644 tools/perf/builtin-ftrace.c diff --git a/tools/perf/Build b/tools/perf/Build index 7039ecb89170..9b79f8d7db50 100644 --- a/tools/perf/Build +++ b/tools/perf/Build @@ -3,6 +3,7 @@ perf-y += builtin-annotate.o perf-y += builtin-config.o perf-y += builtin-diff.o perf-y += builtin-evlist.o +perf-y += builtin-ftrace.o perf-y += builtin-help.o perf-y += builtin-sched.o perf-y += builtin-buildid-list.o diff --git a/tools/perf/Documentation/perf-ftrace.txt b/tools/perf/Documentation/perf-ftrace.txt new file mode 100644 index 000000000000..2d96de6132a9 --- /dev/null +++ b/tools/perf/Documentation/perf-ftrace.txt @@ -0,0 +1,36 @@ +perf-ftrace(1) +============= + +NAME +---- +perf-ftrace - simple wrapper for kernel's ftrace functionality + + +SYNOPSIS +-------- +[verse] +'perf ftrace' + +DESCRIPTION +----------- +The 'perf ftrace' command is a simple wrapper of kernel's ftrace +functionality. It only supports single thread tracing currently and +just reads trace_pipe in text and then write it to stdout. + +The following options apply to perf ftrace. + +OPTIONS +------- + +-t:: +--tracer=:: + Tracer to use: function_graph or function. + +-v:: +--verbose=:: + Verbosity level. + + +SEE ALSO +-------- +linkperf:perf-record[1], linkperf:perf-trace[1] diff --git a/tools/perf/builtin-ftrace.c b/tools/perf/builtin-ftrace.c new file mode 100644 index 000000000000..c320ae25c8e6 --- /dev/null +++ b/tools/perf/builtin-ftrace.c @@ -0,0 +1,242 @@ +/* + * builtin-ftrace.c + * + * Copyright (c) 2013 LG Electronics, Namhyung Kim + * + * Released under the GPL v2. + */ + +#include "builtin.h" +#include "perf.h" + +#include +#include + +#include "debug.h" +#include +#include "evlist.h" +#include "target.h" +#include "thread_map.h" + + +#define DEFAULT_TRACER "function_graph" + +struct perf_ftrace { + struct perf_evlist *evlist; + struct target target; + const char *tracer; +}; + +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) +{ + char *file; + int fd, ret = -1; + ssize_t size = strlen(val); + + file = get_tracing_file(name); + if (!file) { + pr_debug("cannot get tracing file: %s\n", name); + return -1; + } + + fd = open(file, O_WRONLY); + if (fd < 0) { + pr_debug("cannot open tracing file: %s\n", name); + goto out; + } + + if (write(fd, val, size) == size) + ret = 0; + else + pr_debug("write '%s' to tracing/%s failed\n", val, name); + + close(fd); +out: + put_tracing_file(file); + return ret; +} + +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; + + return 0; +} + +static int __cmd_ftrace(struct perf_ftrace *ftrace, int argc, const char **argv) +{ + char *trace_file; + int trace_fd; + char *trace_pid; + char buf[4096]; + struct pollfd pollfd = { + .events = POLLIN, + }; + + if (geteuid() != 0) { + pr_err("ftrace only works for root!\n"); + return -1; + } + + if (argc < 1) + return -1; + + signal(SIGINT, sig_handler); + signal(SIGUSR1, sig_handler); + signal(SIGCHLD, sig_handler); + + reset_tracing_files(ftrace); + + /* reset ftrace buffer */ + if (write_tracing_file("trace", "0") < 0) + goto out; + + if (perf_evlist__prepare_workload(ftrace->evlist, &ftrace->target, + argv, false, ftrace__workload_exec_failed_signal) < 0) + goto out; + + if (write_tracing_file("current_tracer", ftrace->tracer) < 0) { + pr_err("failed to set current_tracer to %s\n", ftrace->tracer); + goto out; + } + + if (asprintf(&trace_pid, "%d", thread_map__pid(ftrace->evlist->threads, 0)) < 0) { + pr_err("failed to allocate pid string\n"); + goto out; + } + + if (write_tracing_file("set_ftrace_pid", trace_pid) < 0) { + pr_err("failed to set pid: %s\n", trace_pid); + goto out_free_pid; + } + + trace_file = get_tracing_file("trace_pipe"); + if (!trace_file) { + pr_err("failed to open trace_pipe\n"); + goto out_free_pid; + } + + 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_free_pid; + } + + 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_free_pid: + free(trace_pid); +out: + reset_tracing_files(ftrace); + + return done ? 0 : -1; +} + +int cmd_ftrace(int argc, const char **argv, const char *prefix __maybe_unused) +{ + int ret; + struct perf_ftrace ftrace = { + .target = { .uid = UINT_MAX, }, + }; + const char * const ftrace_usage[] = { + "perf ftrace [] ", + "perf ftrace [] -- []", + NULL + }; + const struct option ftrace_options[] = { + OPT_STRING('t', "tracer", &ftrace.tracer, "tracer", + "tracer to use: function_graph or function"), + OPT_INCR('v', "verbose", &verbose, + "be more verbose"), + OPT_END() + }; + + argc = parse_options(argc, argv, ftrace_options, ftrace_usage, + PARSE_OPT_STOP_AT_NON_OPTION); + if (!argc) + usage_with_options(ftrace_usage, ftrace_options); + + ftrace.evlist = perf_evlist__new(); + if (ftrace.evlist == NULL) + return -ENOMEM; + + ret = perf_evlist__create_maps(ftrace.evlist, &ftrace.target); + if (ret < 0) + goto out_delete_evlist; + + if (ftrace.tracer == NULL) + ftrace.tracer = DEFAULT_TRACER; + + ret = __cmd_ftrace(&ftrace, argc, argv); + +out_delete_evlist: + perf_evlist__delete(ftrace.evlist); + + return ret; +} diff --git a/tools/perf/builtin.h b/tools/perf/builtin.h index b55f5be486a1..036e1e35b1a8 100644 --- a/tools/perf/builtin.h +++ b/tools/perf/builtin.h @@ -41,6 +41,7 @@ int cmd_trace(int argc, const char **argv, const char *prefix); int cmd_inject(int argc, const char **argv, const char *prefix); int cmd_mem(int argc, const char **argv, const char *prefix); int cmd_data(int argc, const char **argv, const char *prefix); +int cmd_ftrace(int argc, const char **argv, const char *prefix); int find_scripts(char **scripts_array, char **scripts_path_array); #endif diff --git a/tools/perf/command-list.txt b/tools/perf/command-list.txt index fb45613dba9e..ac3efd396a72 100644 --- a/tools/perf/command-list.txt +++ b/tools/perf/command-list.txt @@ -11,6 +11,7 @@ perf-data mainporcelain common perf-diff mainporcelain common perf-config mainporcelain common perf-evlist mainporcelain common +perf-ftrace mainporcelain common perf-inject mainporcelain common perf-kallsyms mainporcelain common perf-kmem mainporcelain common diff --git a/tools/perf/perf.c b/tools/perf/perf.c index 0324cd15e42a..34bcf90f8871 100644 --- a/tools/perf/perf.c +++ b/tools/perf/perf.c @@ -71,6 +71,7 @@ static struct cmd_struct commands[] = { { "inject", cmd_inject, 0 }, { "mem", cmd_mem, 0 }, { "data", cmd_data, 0 }, + { "ftrace", cmd_ftrace, 0 }, }; struct pager_config {