| // Copyright 2017 The Bazel Authors. All rights reserved. |
| // |
| // 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. |
| |
| package com.google.devtools.build.lib.profiler.callcounts; |
| |
| import com.google.common.collect.ImmutableList; |
| import com.google.devtools.build.lib.events.Reporter; |
| import com.google.devtools.build.lib.runtime.BlazeModule; |
| import com.google.devtools.build.lib.runtime.CommandEnvironment; |
| import com.google.devtools.common.options.Option; |
| import com.google.devtools.common.options.OptionDocumentationCategory; |
| import com.google.devtools.common.options.OptionEffectTag; |
| import com.google.devtools.common.options.OptionsBase; |
| import java.io.IOException; |
| |
| /** |
| * Developer utility. Add calls to {@link Callcounts#registerCall} in places that you want to count |
| * call occurrences with call stacks. At the end of the command, a pprof-compatible file will be |
| * dumped to the path specified by --call_count_output_path. |
| */ |
| public class CallcountsModule extends BlazeModule { |
| private static final int MAX_CALLSTACK = 8; |
| // Every Nth call is actually logged |
| private static final int SAMPLE_PERIOD = 100; |
| // We use some variance to avoid patterns where the same calls get logged over and over |
| private static final int SAMPLE_VARIANCE = 10; |
| |
| private String outputPath; |
| private Reporter reporter; |
| |
| /** Options for {@link CallcountsModule}. */ |
| public static class CallcountsOptions extends OptionsBase { |
| @Option( |
| name = "call_count_output_path", |
| help = |
| "An absolute path to a pprof gz file. " |
| + "At the end of the command a call count file will be written.", |
| documentationCategory = OptionDocumentationCategory.UNDOCUMENTED, // Devs only |
| effectTags = {OptionEffectTag.UNKNOWN}, |
| defaultValue = "" |
| ) |
| public String outputPath; |
| } |
| |
| @Override |
| public Iterable<Class<? extends OptionsBase>> getCommonCommandOptions() { |
| return ImmutableList.of(CallcountsOptions.class); |
| } |
| |
| @Override |
| public void beforeCommand(CommandEnvironment env) { |
| this.outputPath = env.getOptions().getOptions(CallcountsOptions.class).outputPath; |
| Callcounts.init(SAMPLE_PERIOD, SAMPLE_VARIANCE, MAX_CALLSTACK); |
| this.reporter = env.getReporter(); |
| } |
| |
| @Override |
| public void afterCommand() { |
| if (!outputPath.isEmpty()) { |
| try { |
| Callcounts.dump(outputPath); |
| } catch (IOException e) { |
| reporter.error(null, "Error saving callcount file", e); |
| } |
| } |
| Callcounts.reset(); |
| this.reporter = null; |
| } |
| } |