/*
* Copyright (C) 2012 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <errno.h>
#include <fcntl.h>
#include <getopt.h>
#include <inttypes.h>
#include <signal.h>
#include <stdarg.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/sendfile.h>
#include <time.h>
#include <zlib.h>
#include <binder/IBinder.h>
#include <binder/IServiceManager.h>
#include <binder/Parcel.h>
#include <cutils/properties.h>
#include <utils/String8.h>
#include <utils/Timers.h>
#include <utils/Trace.h>
using namespace android;
#define NELEM(x) ((int) (sizeof(x) / sizeof((x)[0])))
enum { MAX_SYS_FILES = 10 };
const char* k_traceTagsProperty = "debug.atrace.tags.enableflags";
const char* k_traceAppCmdlineProperty = "debug.atrace.app_cmdlines";
typedef enum { OPT, REQ } requiredness ;
struct TracingCategory {
// The name identifying the category.
const char* name;
// A longer description of the category.
const char* longname;
// The userland tracing tags that the category enables.
uint64_t tags;
// The fname==NULL terminated list of /sys/ files that the category
// enables.
struct {
// Whether the file must be writable in order to enable the tracing
// category.
requiredness required;
// The path to the enable file.
const char* path;
} sysfiles[MAX_SYS_FILES];
};
/* Tracing categories */
static const TracingCategory k_categories[] = {
{ "gfx", "Graphics", ATRACE_TAG_GRAPHICS, { } },
{ "input", "Input", ATRACE_TAG_INPUT, { } },
{ "view", "View System", ATRACE_TAG_VIEW, { } },
{ "webview", "WebView", ATRACE_TAG_WEBVIEW, { } },
{ "wm", "Window Manager", ATRACE_TAG_WINDOW_MANAGER, { } },
{ "am", "Activity Manager", ATRACE_TAG_ACTIVITY_MANAGER, { } },
{ "sm", "Sync Manager", ATRACE_TAG_SYNC_MANAGER, { } },
{ "audio", "Audio", ATRACE_TAG_AUDIO, { } },
{ "video", "Video", ATRACE_TAG_VIDEO, { } },
{ "camera", "Camera", ATRACE_TAG_CAMERA, { } },
{ "hal", "Hardware Modules", ATRACE_TAG_HAL, { } },
{ "app", "Application", ATRACE_TAG_APP, { } },
{ "res", "Resource Loading", ATRACE_TAG_RESOURCES, { } },
{ "dalvik", "Dalvik VM", ATRACE_TAG_DALVIK, { } },
{ "rs", "RenderScript", ATRACE_TAG_RS, { } },
{ "bionic", "Bionic C Library", ATRACE_TAG_BIONIC, { } },
{ "power", "Power Management", ATRACE_TAG_POWER, { } },
{ "sched", "CPU Scheduling", 0, {
{ REQ, "/sys/kernel/debug/tracing/events/sched/sched_switch/enable" },
{ REQ, "/sys/kernel/debug/tracing/events/sched/sched_wakeup/enable" },
} },
{ "irq", "IRQ Events", 0, {
{ REQ, "/sys/kernel/debug/tracing/events/irq/enable" },
} },
{ "freq", "CPU Frequency", 0, {
{ REQ, "/sys/kernel/debug/tracing/events/power/cpu_frequency/enable" },
{ OPT, "/sys/kernel/debug/tracing/events/power/clock_set_rate/enable" },
} },
{ "membus", "Memory Bus Utilization", 0, {
{ REQ, "/sys/kernel/debug/tracing/events/memory_bus/enable" },
} },
{ "idle", "CPU Idle", 0, {
{ REQ, "/sys/kernel/debug/tracing/events/power/cpu_idle/enable" },
} },
{ "disk", "Disk I/O", 0, {
{ OPT, "/sys/kernel/debug/tracing/events/f2fs/f2fs_sync_file_enter/enable" },
{ OPT, "/sys/kernel/debug/tracing/events/f2fs/f2fs_sync_file_exit/enable" },
{ OPT, "/sys/kernel/debug/tracing/events/f2fs/f2fs_write_begin/enable" },
{ OPT, "/sys/kernel/debug/tracing/events/f2fs/f2fs_write_end/enable" },
{ OPT, "/sys/kernel/debug/tracing/events/ext4/ext4_da_write_begin/enable" },
{ OPT, "/sys/kernel/debug/tracing/events/ext4/ext4_da_write_end/enable" },
{ OPT, "/sys/kernel/debug/tracing/events/ext4/ext4_sync_file_enter/enable" },
{ OPT, "/sys/kernel/debug/tracing/events/ext4/ext4_sync_file_exit/enable" },
{ REQ, "/sys/kernel/debug/tracing/events/block/block_rq_issue/enable" },
{ REQ, "/sys/kernel/debug/tracing/events/block/block_rq_complete/enable" },
} },
{ "mmc", "eMMC commands", 0, {
{ REQ, "/sys/kernel/debug/tracing/events/mmc/enable" },
} },
{ "load", "CPU Load", 0, {
{ REQ, "/sys/kernel/debug/tracing/events/cpufreq_interactive/enable" },
} },
{ "sync", "Synchronization", 0, {
{ REQ, "/sys/kernel/debug/tracing/events/sync/enable" },
} },
{ "workq", "Kernel Workqueues", 0, {
{ REQ, "/sys/kernel/debug/tracing/events/workqueue/enable" },
} },
{ "memreclaim", "Kernel Memory Reclaim", 0, {
{ REQ, "/sys/kernel/debug/tracing/events/vmscan/mm_vmscan_direct_reclaim_begin/enable" },
{ REQ, "/sys/kernel/debug/tracing/events/vmscan/mm_vmscan_direct_reclaim_end/enable" },
{ REQ, "/sys/kernel/debug/tracing/events/vmscan/mm_vmscan_kswapd_wake/enable" },
{ REQ, "/sys/kernel/debug/tracing/events/vmscan/mm_vmscan_kswapd_sleep/enable" },
} },
{ "regulators", "Voltage and Current Regulators", 0, {
{ REQ, "/sys/kernel/debug/tracing/events/regulator/enable" },
} },
};
/* Command line options */
static int g_traceDurationSeconds = 5;
static bool g_traceOverwrite = false;
static int g_traceBufferSizeKB = 2048;
static bool g_compress = false;
static bool g_nohup = false;
static int g_initialSleepSecs = 0;
static const char* g_kernelTraceFuncs = NULL;
static const char* g_debugAppCmdLine = "";
/* Global state */
static bool g_traceAborted = false;
static bool g_categoryEnables[NELEM(k_categories)] = {};
/* Sys file paths */
static const char* k_traceClockPath =
"/sys/kernel/debug/tracing/trace_clock";
static const char* k_traceBufferSizePath =
"/sys/kernel/debug/tracing/buffer_size_kb";
static const char* k_tracingOverwriteEnablePath =
"/sys/kernel/debug/tracing/options/overwrite";
static const char* k_currentTracerPath =
"/sys/kernel/debug/tracing/current_tracer";
static const char* k_printTgidPath =
"/sys/kernel/debug/tracing/options/print-tgid";
static const char* k_funcgraphAbsTimePath =
"/sys/kernel/debug/tracing/options/funcgraph-abstime";
static const char* k_funcgraphCpuPath =
"/sys/kernel/debug/tracing/options/funcgraph-cpu";
static const char* k_funcgraphProcPath =
"/sys/kernel/debug/tracing/options/funcgraph-proc";
static const char* k_funcgraphFlatPath =
"/sys/kernel/debug/tracing/options/funcgraph-flat";
static const char* k_funcgraphDurationPath =
"/sys/kernel/debug/tracing/options/funcgraph-duration";
static const char* k_ftraceFilterPath =
"/sys/kernel/debug/tracing/set_ftrace_filter";
static const char* k_tracingOnPath =
"/sys/kernel/debug/tracing/tracing_on";
static const char* k_tracePath =
"/sys/kernel/debug/tracing/trace";
static const char* k_traceMarkerPath =
"/sys/kernel/debug/tracing/trace_marker";
// Check whether a file exists.
static bool fileExists(const char* filename) {
return access(filename, F_OK) != -1;
}
// Check whether a file is writable.
static bool fileIsWritable(const char* filename) {
return access(filename, W_OK) != -1;
}
// Truncate a file.
static bool truncateFile(const char* path)
{
// This uses creat rather than truncate because some of the debug kernel
// device nodes (e.g. k_ftraceFilterPath) currently aren't changed by
// calls to truncate, but they are cleared by calls to creat.
int traceFD = creat(path, 0);
if (traceFD == -1) {
fprintf(stderr, "error truncating %s: %s (%d)\n", path,
strerror(errno), errno);
return false;
}
close(traceFD);
return true;
}
static bool _writeStr(const char* filename, const char* str, int flags)
{
int fd = open(filename, flags);
if (fd == -1) {
fprintf(stderr, "error opening %s: %s (%d)\n", filename,
strerror(errno), errno);
return false;
}
bool ok = true;
ssize_t len = strlen(str);
if (write(fd, str, len) != len) {
fprintf(stderr, "error writing to %s: %s (%d)\n", filename,
strerror(errno), errno);
ok = false;
}
close(fd);
return ok;
}
// Write a string to a file, returning true if the write was successful.
static bool writeStr(const char* filename, const char* str)
{
return _writeStr(filename, str, O_WRONLY);
}
// Append a string to a file, returning true if the write was successful.
static bool appendStr(const char* filename, const char* str)
{
return _writeStr(filename, str, O_APPEND|O_WRONLY);
}
static void writeClockSyncMarker()
{
char buffer[128];
int len = 0;
int fd = open(k_traceMarkerPath, O_WRONLY);
if (fd == -1) {
fprintf(stderr, "error opening %s: %s (%d)\n", k_traceMarkerPath,
strerror(errno), errno);
return;
}
float now_in_seconds = systemTime(CLOCK_MONOTONIC) / 1000000000.0f;
len = snprintf(buffer, 128, "trace_event_clock_sync: parent_ts=%f\n", now_in_seconds);
if (write(fd, buffer, len) != len) {
fprintf(stderr, "error writing clock sync marker %s (%d)\n", strerror(errno), errno);
}
int64_t realtime_in_ms = systemTime(CLOCK_REALTIME) / 1000000;
len = snprintf(buffer, 128, "trace_event_clock_sync: realtime_ts=%" PRId64 "\n", realtime_in_ms);
if (write(fd, buffer, len) != len) {
fprintf(stderr, "error writing clock sync marker %s (%d)\n", strerror(errno), errno);
}
close(fd);
}
// Enable or disable a kernel option by writing a "1" or a "0" into a /sys
// file.
static bool setKernelOptionEnable(const char* filename, bool enable)
{
return writeStr(filename, enable ? "1" : "0");
}
// Check whether the category is supported on the device with the current
// rootness. A category is supported only if all its required /sys/ files are
// writable and if enabling the category will enable one or more tracing tags
// or /sys/ files.
static bool isCategorySupported(const TracingCategory& category)
{
bool ok = category.tags != 0;
for (int i = 0; i < MAX_SYS_FILES; i++) {
const char* path = category.sysfiles[i].path;
bool req = category.sysfiles[i].required == REQ;
if (path != NULL) {
if (req) {
if (!fileIsWritable(path)) {
return false;
} else {
ok = true;
}
} else {
ok |= fileIsWritable(path);
}
}
}
return ok;
}
// Check whether the category would be supported on the device if the user
// were root. This function assumes that root is able to write to any file
// that exists. It performs the same logic as isCategorySupported, but it
// uses file existance rather than writability in the /sys/ file checks.
static bool isCategorySupportedForRoot(const TracingCategory& category)
{
bool ok = category.tags != 0;
for (int i = 0; i < MAX_SYS_FILES; i++) {
const char* path = category.sysfiles[i].path;
bool req = category.sysfiles[i].required == REQ;
if (path != NULL) {
if (req) {
if (!fileExists(path)) {
return false;
} else {
ok = true;
}
} else {
ok |= fileExists(path);
}
}
}
return ok;
}
// Enable or disable overwriting of the kernel trace buffers. Disabling this
// will cause tracing to stop once the trace buffers have filled up.
static bool setTraceOverwriteEnable(bool enable)
{
return setKernelOptionEnable(k_tracingOverwriteEnablePath, enable);
}
// Enable or disable kernel tracing.
static bool setTracingEnabled(bool enable)
{
return setKernelOptionEnable(k_tracingOnPath, enable);
}
// Clear the contents of the kernel trace.
static bool clearTrace()
{
return truncateFile(k_tracePath);
}
// Set the size of the kernel's trace buffer in kilobytes.
static bool setTraceBufferSizeKB(int size)
{
char str[32] = "1";
int len;
if (size < 1) {
size = 1;
}
snprintf(str, 32, "%d", size);
return writeStr(k_traceBufferSizePath, str);
}
// Read the trace_clock sysfs file and return true if it matches the requested
// value. The trace_clock file format is:
// local [global] counter uptime perf
static bool isTraceClock(const char *mode)
{
int fd = open(k_traceClockPath, O_RDONLY);
if (fd == -1) {
fprintf(stderr, "error opening %s: %s (%d)\n", k_traceClockPath,
strerror(errno), errno);
return false;
}
char buf[4097];
ssize_t n = read(fd, buf, 4096);
close(fd);
if (n == -1) {
fprintf(stderr, "error reading %s: %s (%d)\n", k_traceClockPath,
strerror(errno), errno);
return false;
}
buf[n] = '\0';
char *start = strchr(buf, '[');
if (start == NULL) {
return false;
}
start++;
char *end = strchr(start, ']');
if (end == NULL) {
return false;
}
*end = '\0';
return strcmp(mode, start) == 0;
}
// Enable or disable the kernel's use of the global clock. Disabling the global
// clock will result in the kernel using a per-CPU local clock.
// Any write to the trace_clock sysfs file will reset the buffer, so only
// update it if the requested value is not the current value.
static bool setGlobalClockEnable(bool enable)
{
const char *clock = enable ? "global" : "local";
if (isTraceClock(clock)) {
return true;
}
return writeStr(k_traceClockPath, clock);
}
static bool setPrintTgidEnableIfPresent(bool enable)
{
if (fileExists(k_printTgidPath)) {
return setKernelOptionEnable(k_printTgidPath, enable);
}
return true;
}
// Poke all the binder-enabled processes in the system to get them to re-read
// their system properties.
static bool pokeBinderServices()
{
sp<IServiceManager> sm = defaultServiceManager();
Vector<String16> services = sm->listServices();
for (size_t i = 0; i < services.size(); i++) {
sp<IBinder> obj = sm->checkService(services[i]);
if (obj != NULL) {
Parcel data;
if (obj->transact(IBinder::SYSPROPS_TRANSACTION, data,
NULL, 0) != OK) {
if (false) {
// XXX: For some reason this fails on tablets trying to
// poke the "phone" service. It's not clear whether some
// are expected to fail.
String8 svc(services[i]);
fprintf(stderr, "error poking binder service %s\n",
svc.string());
return false;
}
}
}
}
return true;
}
// Set the trace tags that userland tracing uses, and poke the running
// processes to pick up the new value.
static bool setTagsProperty(uint64_t tags)
{
char buf[64];
snprintf(buf, 64, "%#" PRIx64, tags);
if (property_set(k_traceTagsProperty, buf) < 0) {
fprintf(stderr, "error setting trace tags system property\n");
return false;
}
return true;
}
// Set the system property that indicates which apps should perform
// application-level tracing.
static bool setAppCmdlineProperty(const char* cmdline)
{
if (property_set(k_traceAppCmdlineProperty, cmdline) < 0) {
fprintf(stderr, "error setting trace app system property\n");
return false;
}
return true;
}
// Disable all /sys/ enable files.
static bool disableKernelTraceEvents() {
bool ok = true;
for (int i = 0; i < NELEM(k_categories); i++) {
const TracingCategory &c = k_categories[i];
for (int j = 0; j < MAX_SYS_FILES; j++) {
const char* path = c.sysfiles[j].path;
if (path != NULL && fileIsWritable(path)) {
ok &= setKernelOptionEnable(path, false);
}
}
}
return ok;
}
// Verify that the comma separated list of functions are being traced by the
// kernel.
static bool verifyKernelTraceFuncs(const char* funcs)
{
int fd = open(k_ftraceFilterPath, O_RDONLY);
if (fd == -1) {
fprintf(stderr, "error opening %s: %s (%d)\n", k_ftraceFilterPath,
strerror(errno), errno);
return false;
}
char buf[4097];
ssize_t n = read(fd, buf, 4096);
close(fd);
if (n == -1) {
fprintf(stderr, "error reading %s: %s (%d)\n", k_ftraceFilterPath,
strerror(errno), errno);
return false;
}
buf[n] = '\0';
String8 funcList = String8::format("\n%s", buf);
// Make sure that every function listed in funcs is in the list we just
// read from the kernel.
bool ok = true;
char* myFuncs = strdup(funcs);
char* func = strtok(myFuncs, ",");
while (func) {
String8 fancyFunc = String8::format("\n%s\n", func);
bool found = funcList.find(fancyFunc.string(), 0) >= 0;
if (!found || func[0] == '\0') {
fprintf(stderr, "error: \"%s\" is not a valid kernel function "
"to trace.\n", func);
ok = false;
}
func = strtok(NULL, ",");
}
free(myFuncs);
return ok;
}
// Set the comma separated list of functions that the kernel is to trace.
static bool setKernelTraceFuncs(const char* funcs)
{
bool ok = true;
if (funcs == NULL || funcs[0] == '\0') {
// Disable kernel function tracing.
if (fileIsWritable(k_currentTracerPath)) {
ok &= writeStr(k_currentTracerPath, "nop");
}
if (fileIsWritable(k_ftraceFilterPath)) {
ok &= truncateFile(k_ftraceFilterPath);
}
} else {
// Enable kernel function tracing.
ok &= writeStr(k_currentTracerPath, "function_graph");
ok &= setKernelOptionEnable(k_funcgraphAbsTimePath, true);
ok &= setKernelOptionEnable(k_funcgraphCpuPath, true);
ok &= setKernelOptionEnable(k_funcgraphProcPath, true);
ok &= setKernelOptionEnable(k_funcgraphFlatPath, true);
// Set the requested filter functions.
ok &= truncateFile(k_ftraceFilterPath);
char* myFuncs = strdup(funcs);
char* func = strtok(myFuncs, ",");
while (func) {
ok &= appendStr(k_ftraceFilterPath, func);
func = strtok(NULL, ",");
}
free(myFuncs);
// Verify that the set functions are being traced.
if (ok) {
ok &= verifyKernelTraceFuncs(funcs);
}
}
return ok;
}
// Set all the kernel tracing settings to the desired state for this trace
// capture.
static bool setUpTrace()
{
bool ok = true;
// Set up the tracing options.
ok &= setTraceOverwriteEnable(g_traceOverwrite);
ok &= setTraceBufferSizeKB(g_traceBufferSizeKB);
ok &= setGlobalClockEnable(true);
ok &= setPrintTgidEnableIfPresent(true);
ok &= setKernelTraceFuncs(g_kernelTraceFuncs);
// Set up the tags property.
uint64_t tags = 0;
for (int i = 0; i < NELEM(k_categories); i++) {
if (g_categoryEnables[i]) {
const TracingCategory &c = k_categories[i];
tags |= c.tags;
}
}
ok &= setTagsProperty(tags);
ok &= setAppCmdlineProperty(g_debugAppCmdLine);
ok &= pokeBinderServices();
// Disable all the sysfs enables. This is done as a separate loop from
// the enables to allow the same enable to exist in multiple categories.
ok &= disableKernelTraceEvents();
// Enable all the sysfs enables that are in an enabled category.
for (int i = 0; i < NELEM(k_categories); i++) {
if (g_categoryEnables[i]) {
const TracingCategory &c = k_categories[i];
for (int j = 0; j < MAX_SYS_FILES; j++) {
const char* path = c.sysfiles[j].path;
bool required = c.sysfiles[j].required == REQ;
if (path != NULL) {
if (fileIsWritable(path)) {
ok &= setKernelOptionEnable(path, true);
} else if (required) {
fprintf(stderr, "error writing file %s\n", path);
ok = false;
}
}
}
}
}
return ok;
}
// Reset all the kernel tracing settings to their default state.
static void cleanUpTrace()
{
// Disable all tracing that we're able to.
disableKernelTraceEvents();
// Reset the system properties.
setTagsProperty(0);
setAppCmdlineProperty("");
pokeBinderServices();
// Set the options back to their defaults.
setTraceOverwriteEnable(true);
setTraceBufferSizeKB(1);
setGlobalClockEnable(false);
setPrintTgidEnableIfPresent(false);
setKernelTraceFuncs(NULL);
}
// Enable tracing in the kernel.
static bool startTrace()
{
return setTracingEnabled(true);
}
// Disable tracing in the kernel.
static void stopTrace()
{
setTracingEnabled(false);
}
// Read the current kernel trace and write it to stdout.
static void dumpTrace()
{
int traceFD = open(k_tracePath, O_RDWR);
if (traceFD == -1) {
fprintf(stderr, "error opening %s: %s (%d)\n", k_tracePath,
strerror(errno), errno);
return;
}
if (g_compress) {
z_stream zs;
uint8_t *in, *out;
int result, flush;
memset(&zs, 0, sizeof(zs));
result = deflateInit(&zs, Z_DEFAULT_COMPRESSION);
if (result != Z_OK) {
fprintf(stderr, "error initializing zlib: %d\n", result);
close(traceFD);
return;
}
const size_t bufSize = 64*1024;
in = (uint8_t*)malloc(bufSize);
out = (uint8_t*)malloc(bufSize);
flush = Z_NO_FLUSH;
zs.next_out = out;
zs.avail_out = bufSize;
do {
if (zs.avail_in == 0) {
// More input is needed.
result = read(traceFD, in, bufSize);
if (result < 0) {
fprintf(stderr, "error reading trace: %s (%d)\n",
strerror(errno), errno);
result = Z_STREAM_END;
break;
} else if (result == 0) {
flush = Z_FINISH;
} else {
zs.next_in = in;
zs.avail_in = result;
}
}
if (zs.avail_out == 0) {
// Need to write the output.
result = write(STDOUT_FILENO, out, bufSize);
if ((size_t)result < bufSize) {
fprintf(stderr, "error writing deflated trace: %s (%d)\n",
strerror(errno), errno);
result = Z_STREAM_END; // skip deflate error message
zs.avail_out = bufSize; // skip the final write
break;
}
zs.next_out = out;
zs.avail_out = bufSize;
}
} while ((result = deflate(&zs, flush)) == Z_OK);
if (result != Z_STREAM_END) {
fprintf(stderr, "error deflating trace: %s\n", zs.msg);
}
if (zs.avail_out < bufSize) {
size_t bytes = bufSize - zs.avail_out;
result = write(STDOUT_FILENO, out, bytes);
if ((size_t)result < bytes) {
fprintf(stderr, "error writing deflated trace: %s (%d)\n",
strerror(errno), errno);
}
}
result = deflateEnd(&zs);
if (result != Z_OK) {
fprintf(stderr, "error cleaning up zlib: %d\n", result);
}
free(in);
free(out);
} else {
ssize_t sent = 0;
while ((sent = sendfile(STDOUT_FILENO, traceFD, NULL, 64*1024*1024)) > 0);
if (sent == -1) {
fprintf(stderr, "error dumping trace: %s (%d)\n", strerror(errno),
errno);
}
}
close(traceFD);
}
static void handleSignal(int /*signo*/)
{
if (!g_nohup) {
g_traceAborted = true;
}
}
static void registerSigHandler()
{
struct sigaction sa;
sigemptyset(&sa.sa_mask);
sa.sa_flags = 0;
sa.sa_handler = handleSignal;
sigaction(SIGHUP, &sa, NULL);
sigaction(SIGINT, &sa, NULL);
sigaction(SIGQUIT, &sa, NULL);
sigaction(SIGTERM, &sa, NULL);
}
static bool setCategoryEnable(const char* name, bool enable)
{
for (int i = 0; i < NELEM(k_categories); i++) {
const TracingCategory& c = k_categories[i];
if (strcmp(name, c.name) == 0) {
if (isCategorySupported(c)) {
g_categoryEnables[i] = enable;
return true;
} else {
if (isCategorySupportedForRoot(c)) {
fprintf(stderr, "error: category \"%s\" requires root "
"privileges.\n", name);
} else {
fprintf(stderr, "error: category \"%s\" is not supported "
"on this device.\n", name);
}
return false;
}
}
}
fprintf(stderr, "error: unknown tracing category \"%s\"\n", name);
return false;
}
static void listSupportedCategories()
{
for (int i = 0; i < NELEM(k_categories); i++) {
const TracingCategory& c = k_categories[i];
if (isCategorySupported(c)) {
printf(" %10s - %s\n", c.name, c.longname);
}
}
}
// Print the command usage help to stderr.
static void showHelp(const char *cmd)
{
fprintf(stderr, "usage: %s [options] [categories...]\n", cmd);
fprintf(stderr, "options include:\n"
" -a appname enable app-level tracing for a comma "
"separated list of cmdlines\n"
" -b N use a trace buffer size of N KB\n"
" -c trace into a circular buffer\n"
" -k fname,... trace the listed kernel functions\n"
" -n ignore signals\n"
" -s N sleep for N seconds before tracing [default 0]\n"
" -t N trace for N seconds [defualt 5]\n"
" -z compress the trace dump\n"
" --async_start start circular trace and return immediatly\n"
" --async_dump dump the current contents of circular trace buffer\n"
" --async_stop stop tracing and dump the current contents of circular\n"
" trace buffer\n"
" --list_categories\n"
" list the available tracing categories\n"
);
}
int main(int argc, char **argv)
{
bool async = false;
bool traceStart = true;
bool traceStop = true;
bool traceDump = true;
if (argc == 2 && 0 == strcmp(argv[1], "--help")) {
showHelp(argv[0]);
exit(0);
}
for (;;) {
int ret;
int option_index = 0;
static struct option long_options[] = {
{"async_start", no_argument, 0, 0 },
{"async_stop", no_argument, 0, 0 },
{"async_dump", no_argument, 0, 0 },
{"list_categories", no_argument, 0, 0 },
{ 0, 0, 0, 0 }
};
ret = getopt_long(argc, argv, "a:b:ck:ns:t:z",
long_options, &option_index);
if (ret < 0) {
for (int i = optind; i < argc; i++) {
if (!setCategoryEnable(argv[i], true)) {
fprintf(stderr, "error enabling tracing category \"%s\"\n", argv[i]);
exit(1);
}
}
break;
}
switch(ret) {
case 'a':
g_debugAppCmdLine = optarg;
break;
case 'b':
g_traceBufferSizeKB = atoi(optarg);
break;
case 'c':
g_traceOverwrite = true;
break;
case 'k':
g_kernelTraceFuncs = optarg;
break;
case 'n':
g_nohup = true;
break;
case 's':
g_initialSleepSecs = atoi(optarg);
break;
case 't':
g_traceDurationSeconds = atoi(optarg);
break;
case 'z':
g_compress = true;
break;
case 0:
if (!strcmp(long_options[option_index].name, "async_start")) {
async = true;
traceStop = false;
traceDump = false;
g_traceOverwrite = true;
} else if (!strcmp(long_options[option_index].name, "async_stop")) {
async = true;
traceStart = false;
} else if (!strcmp(long_options[option_index].name, "async_dump")) {
async = true;
traceStart = false;
traceStop = false;
} else if (!strcmp(long_options[option_index].name, "list_categories")) {
listSupportedCategories();
exit(0);
}
break;
default:
fprintf(stderr, "\n");
showHelp(argv[0]);
exit(-1);
break;
}
}
registerSigHandler();
if (g_initialSleepSecs > 0) {
sleep(g_initialSleepSecs);
}
bool ok = true;
ok &= setUpTrace();
ok &= startTrace();
if (ok && traceStart) {
printf("capturing trace...");
fflush(stdout);
// We clear the trace after starting it because tracing gets enabled for
// each CPU individually in the kernel. Having the beginning of the trace
// contain entries from only one CPU can cause "begin" entries without a
// matching "end" entry to show up if a task gets migrated from one CPU to
// another.
ok = clearTrace();
writeClockSyncMarker();
if (ok && !async) {
// Sleep to allow the trace to be captured.
struct timespec timeLeft;
timeLeft.tv_sec = g_traceDurationSeconds;
timeLeft.tv_nsec = 0;
do {
if (g_traceAborted) {
break;
}
} while (nanosleep(&timeLeft, &timeLeft) == -1 && errno == EINTR);
}
}
// Stop the trace and restore the default settings.
if (traceStop)
stopTrace();
if (ok && traceDump) {
if (!g_traceAborted) {
printf(" done\nTRACE:\n");
fflush(stdout);
dumpTrace();
} else {
printf("\ntrace aborted.\n");
fflush(stdout);
}
clearTrace();
} else if (!ok) {
fprintf(stderr, "unable to start tracing\n");
}
// Reset the trace buffer size to 1.
if (traceStop)
cleanUpTrace();
return g_traceAborted ? 1 : 0;
}