--- /dev/null
+
+ 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.
+
+ 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.
+
+
+ Apache License
+ Version 2.0, January 2004
+ http://www.apache.org/licenses/
+
+ TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+ 1. Definitions.
+
+ "License" shall mean the terms and conditions for use, reproduction,
+ and distribution as defined by Sections 1 through 9 of this document.
+
+ "Licensor" shall mean the copyright owner or entity authorized by
+ the copyright owner that is granting the License.
+
+ "Legal Entity" shall mean the union of the acting entity and all
+ other entities that control, are controlled by, or are under common
+ control with that entity. For the purposes of this definition,
+ "control" means (i) the power, direct or indirect, to cause the
+ direction or management of such entity, whether by contract or
+ otherwise, or (ii) ownership of fifty percent (50%) or more of the
+ outstanding shares, or (iii) beneficial ownership of such entity.
+
+ "You" (or "Your") shall mean an individual or Legal Entity
+ exercising permissions granted by this License.
+
+ "Source" form shall mean the preferred form for making modifications,
+ including but not limited to software source code, documentation
+ source, and configuration files.
+
+ "Object" form shall mean any form resulting from mechanical
+ transformation or translation of a Source form, including but
+ not limited to compiled object code, generated documentation,
+ and conversions to other media types.
+
+ "Work" shall mean the work of authorship, whether in Source or
+ Object form, made available under the License, as indicated by a
+ copyright notice that is included in or attached to the work
+ (an example is provided in the Appendix below).
+
+ "Derivative Works" shall mean any work, whether in Source or Object
+ form, that is based on (or derived from) the Work and for which the
+ editorial revisions, annotations, elaborations, or other modifications
+ represent, as a whole, an original work of authorship. For the purposes
+ of this License, Derivative Works shall not include works that remain
+ separable from, or merely link (or bind by name) to the interfaces of,
+ the Work and Derivative Works thereof.
+
+ "Contribution" shall mean any work of authorship, including
+ the original version of the Work and any modifications or additions
+ to that Work or Derivative Works thereof, that is intentionally
+ submitted to Licensor for inclusion in the Work by the copyright owner
+ or by an individual or Legal Entity authorized to submit on behalf of
+ the copyright owner. For the purposes of this definition, "submitted"
+ means any form of electronic, verbal, or written communication sent
+ to the Licensor or its representatives, including but not limited to
+ communication on electronic mailing lists, source code control systems,
+ and issue tracking systems that are managed by, or on behalf of, the
+ Licensor for the purpose of discussing and improving the Work, but
+ excluding communication that is conspicuously marked or otherwise
+ designated in writing by the copyright owner as "Not a Contribution."
+
+ "Contributor" shall mean Licensor and any individual or Legal Entity
+ on behalf of whom a Contribution has been received by Licensor and
+ subsequently incorporated within the Work.
+
+ 2. Grant of Copyright License. Subject to the terms and conditions of
+ this License, each Contributor hereby grants to You a perpetual,
+ worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+ copyright license to reproduce, prepare Derivative Works of,
+ publicly display, publicly perform, sublicense, and distribute the
+ Work and such Derivative Works in Source or Object form.
+
+ 3. Grant of Patent License. Subject to the terms and conditions of
+ this License, each Contributor hereby grants to You a perpetual,
+ worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+ (except as stated in this section) patent license to make, have made,
+ use, offer to sell, sell, import, and otherwise transfer the Work,
+ where such license applies only to those patent claims licensable
+ by such Contributor that are necessarily infringed by their
+ Contribution(s) alone or by combination of their Contribution(s)
+ with the Work to which such Contribution(s) was submitted. If You
+ institute patent litigation against any entity (including a
+ cross-claim or counterclaim in a lawsuit) alleging that the Work
+ or a Contribution incorporated within the Work constitutes direct
+ or contributory patent infringement, then any patent licenses
+ granted to You under this License for that Work shall terminate
+ as of the date such litigation is filed.
+
+ 4. Redistribution. You may reproduce and distribute copies of the
+ Work or Derivative Works thereof in any medium, with or without
+ modifications, and in Source or Object form, provided that You
+ meet the following conditions:
+
+ (a) You must give any other recipients of the Work or
+ Derivative Works a copy of this License; and
+
+ (b) You must cause any modified files to carry prominent notices
+ stating that You changed the files; and
+
+ (c) You must retain, in the Source form of any Derivative Works
+ that You distribute, all copyright, patent, trademark, and
+ attribution notices from the Source form of the Work,
+ excluding those notices that do not pertain to any part of
+ the Derivative Works; and
+
+ (d) If the Work includes a "NOTICE" text file as part of its
+ distribution, then any Derivative Works that You distribute must
+ include a readable copy of the attribution notices contained
+ within such NOTICE file, excluding those notices that do not
+ pertain to any part of the Derivative Works, in at least one
+ of the following places: within a NOTICE text file distributed
+ as part of the Derivative Works; within the Source form or
+ documentation, if provided along with the Derivative Works; or,
+ within a display generated by the Derivative Works, if and
+ wherever such third-party notices normally appear. The contents
+ of the NOTICE file are for informational purposes only and
+ do not modify the License. You may add Your own attribution
+ notices within Derivative Works that You distribute, alongside
+ or as an addendum to the NOTICE text from the Work, provided
+ that such additional attribution notices cannot be construed
+ as modifying the License.
+
+ You may add Your own copyright statement to Your modifications and
+ may provide additional or different license terms and conditions
+ for use, reproduction, or distribution of Your modifications, or
+ for any such Derivative Works as a whole, provided Your use,
+ reproduction, and distribution of the Work otherwise complies with
+ the conditions stated in this License.
+
+ 5. Submission of Contributions. Unless You explicitly state otherwise,
+ any Contribution intentionally submitted for inclusion in the Work
+ by You to the Licensor shall be under the terms and conditions of
+ this License, without any additional terms or conditions.
+ Notwithstanding the above, nothing herein shall supersede or modify
+ the terms of any separate license agreement you may have executed
+ with Licensor regarding such Contributions.
+
+ 6. Trademarks. This License does not grant permission to use the trade
+ names, trademarks, service marks, or product names of the Licensor,
+ except as required for reasonable and customary use in describing the
+ origin of the Work and reproducing the content of the NOTICE file.
+
+ 7. Disclaimer of Warranty. Unless required by applicable law or
+ agreed to in writing, Licensor provides the Work (and each
+ Contributor provides its Contributions) on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+ implied, including, without limitation, any warranties or conditions
+ of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
+ PARTICULAR PURPOSE. You are solely responsible for determining the
+ appropriateness of using or redistributing the Work and assume any
+ risks associated with Your exercise of permissions under this License.
+
+ 8. Limitation of Liability. In no event and under no legal theory,
+ whether in tort (including negligence), contract, or otherwise,
+ unless required by applicable law (such as deliberate and grossly
+ negligent acts) or agreed to in writing, shall any Contributor be
+ liable to You for damages, including any direct, indirect, special,
+ incidental, or consequential damages of any character arising as a
+ result of this License or out of the use or inability to use the
+ Work (including but not limited to damages for loss of goodwill,
+ work stoppage, computer failure or malfunction, or any and all
+ other commercial damages or losses), even if such Contributor
+ has been advised of the possibility of such damages.
+
+ 9. Accepting Warranty or Additional Liability. While redistributing
+ the Work or Derivative Works thereof, You may choose to offer,
+ and charge a fee for, acceptance of support, warranty, indemnity,
+ or other liability obligations and/or rights consistent with this
+ License. However, in accepting such obligations, You may act only
+ on Your own behalf and on Your sole responsibility, not on behalf
+ of any other Contributor, and only if You agree to indemnify,
+ defend, and hold each Contributor harmless for any liability
+ incurred by, or claims asserted against, such Contributor by reason
+ of your accepting any such warranty or additional liability.
+
+ END OF TERMS AND CONDITIONS
+
--- /dev/null
+/*
+ * 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 <signal.h>
+#include <stdarg.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/sendfile.h>
+#include <time.h>
+
+/* Command line options */
+static int g_traceDurationSeconds = 5;
+static bool g_traceSchedSwitch = false;
+static bool g_traceWorkqueue = false;
+static bool g_traceOverwrite = false;
+
+/* Global state */
+static bool g_traceAborted = false;
+
+/* Sys file paths */
+static const char* k_traceClockPath =
+ "/sys/kernel/debug/tracing/trace_clock";
+
+static const char* k_tracingOverwriteEnablePath =
+ "/sys/kernel/debug/tracing/options/overwrite";
+
+static const char* k_schedSwitchEnablePath =
+ "/sys/kernel/debug/tracing/events/sched/sched_switch/enable";
+
+static const char* k_workqueueEnablePath =
+ "/sys/kernel/debug/tracing/events/workqueue/enable";
+
+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";
+
+// Write a string to a file, returning true if the write was successful.
+bool writeStr(const char* filename, const char* str)
+{
+ int fd = open(filename, O_WRONLY);
+ 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;
+}
+
+// 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");
+}
+
+// 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 tracing of the kernel scheduler switching.
+static bool setSchedSwitchTracingEnable(bool enable)
+{
+ return setKernelOptionEnable(k_schedSwitchEnablePath, enable);
+}
+
+// Enable or disable tracing of the kernel workqueues.
+static bool setWorkqueueTracingEnabled(bool enable)
+{
+ return setKernelOptionEnable(k_workqueueEnablePath, 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()
+{
+ int traceFD = creat(k_tracePath, 0);
+ if (traceFD == -1) {
+ fprintf(stderr, "error truncating %s: %s (%d)\n", k_tracePath,
+ strerror(errno), errno);
+ return false;
+ }
+
+ close(traceFD);
+
+ return true;
+}
+
+// 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.
+static bool setGlobalClockEnable(bool enable)
+{
+ return writeStr(k_traceClockPath, enable ? "global" : "local");
+}
+
+// Enable tracing in the kernel.
+static bool startTrace()
+{
+ bool ok = true;
+
+ // Set up the tracing options.
+ ok &= setTraceOverwriteEnable(g_traceOverwrite);
+ ok &= setSchedSwitchTracingEnable(g_traceSchedSwitch);
+ ok &= setWorkqueueTracingEnabled(g_traceWorkqueue);
+ ok &= setGlobalClockEnable(true);
+
+ // Enable tracing.
+ ok &= setTracingEnabled(true);
+
+ if (!ok) {
+ fprintf(stderr, "error: unable to start trace\n");
+ }
+
+ return ok;
+}
+
+// Disable tracing in the kernel.
+static void stopTrace()
+{
+ // Disable tracing.
+ setTracingEnabled(false);
+
+ // Set the options back to their defaults.
+ setTraceOverwriteEnable(true);
+ setSchedSwitchTracingEnable(false);
+ setWorkqueueTracingEnabled(false);
+ setGlobalClockEnable(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;
+ }
+
+ 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);
+}
+
+// Print the command usage help to stderr.
+static void showHelp(const char *cmd)
+{
+ fprintf(stderr, "usage: %s [options]\n", cmd);
+ fprintf(stderr, "options include:\n"
+ " -c trace into a circular buffer\n"
+ " -s trace the kernel scheduler switches\n"
+ " -t N trace for N seconds [defualt 5]\n"
+ " -w trace the kernel workqueue\n");
+}
+
+static void handleSignal(int signo) {
+ 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);
+}
+
+int main(int argc, char **argv)
+{
+ if (argc == 2 && 0 == strcmp(argv[1], "--help")) {
+ showHelp(argv[0]);
+ exit(0);
+ }
+
+ if (getuid() != 0) {
+ fprintf(stderr, "error: %s must be run as root.", argv[0]);
+ }
+
+ for (;;) {
+ int ret;
+
+ ret = getopt(argc, argv, "cst:w");
+
+ if (ret < 0) {
+ break;
+ }
+
+ switch(ret) {
+ case 'c':
+ g_traceOverwrite = true;
+ break;
+
+ case 's':
+ g_traceSchedSwitch = true;
+ break;
+
+ case 't':
+ g_traceDurationSeconds = atoi(optarg);
+ break;
+
+ case 'w':
+ g_traceWorkqueue = true;
+ break;
+
+ default:
+ showHelp(argv[0]);
+ exit(-1);
+ break;
+ }
+ }
+
+ registerSigHandler();
+
+ bool ok = startTrace();
+
+ if (ok) {
+ 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();
+
+ if (ok) {
+ // 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.
+ stopTrace();
+
+ if (ok) {
+ if (!g_traceAborted) {
+ printf(" done\nTRACE:\n");
+ fflush(stdout);
+ dumpTrace();
+ } else {
+ printf("\ntrace aborted.\n");
+ fflush(stdout);
+ }
+ clearTrace();
+ } else {
+ fprintf(stderr, "unable to start tracing\n");
+ }
+
+ return g_traceAborted ? 1 : 0;
+}
OSDN Git Service
