dart-sdk/runtime/vm/timeline_linux.cc
Ryan Macnak 3d21a46b72 Limit preserialized JSON for timeline events from Dart code to the arguments.
Avoids string copies in C++ and map copies in Dart.

Also remove some vestiages of removed feature that allowed an embedder to add pre-encoded events to the timeline.

Change-Id: I962a67093ba461c991d9169b0391c44af1d489db
Bug: https://github.com/dart-lang/sdk/issues/30787
Reviewed-on: https://dart-review.googlesource.com/6762
Commit-Queue: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Zach Anderson <zra@google.com>
2017-09-19 23:29:55 +00:00

125 lines
3.8 KiB
C++

// Copyright (c) 2017, the Dart project authors. Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.
#include "platform/globals.h"
#if defined(HOST_OS_LINUX) && !defined(PRODUCT)
#include <errno.h>
#include <fcntl.h>
#include <cstdlib>
#include "vm/atomic.h"
#include "vm/isolate.h"
#include "vm/json_stream.h"
#include "vm/lockers.h"
#include "vm/log.h"
#include "vm/object.h"
#include "vm/service_event.h"
#include "vm/thread.h"
#include "vm/timeline.h"
namespace dart {
DECLARE_FLAG(bool, trace_timeline);
TimelineEventSystraceRecorder::TimelineEventSystraceRecorder(intptr_t capacity)
: TimelineEventPlatformRecorder(capacity), systrace_fd_(-1) {
const char* kSystracePath = "/sys/kernel/debug/tracing/trace_marker";
systrace_fd_ = open(kSystracePath, O_WRONLY);
if ((systrace_fd_ < 0) && FLAG_trace_timeline) {
OS::PrintErr("TimelineEventSystraceRecorder: Could not open `%s`\n",
kSystracePath);
}
}
TimelineEventSystraceRecorder::~TimelineEventSystraceRecorder() {
if (systrace_fd_ >= 0) {
close(systrace_fd_);
}
}
intptr_t TimelineEventSystraceRecorder::PrintSystrace(TimelineEvent* event,
char* buffer,
intptr_t buffer_size) {
ASSERT(buffer != NULL);
ASSERT(buffer_size > 0);
buffer[0] = '\0';
intptr_t length = 0;
int64_t pid = OS::ProcessId();
switch (event->event_type()) {
case TimelineEvent::kBegin: {
length = OS::SNPrint(buffer, buffer_size, "B|%" Pd64 "|%s", pid,
event->label());
} break;
case TimelineEvent::kEnd: {
length = OS::SNPrint(buffer, buffer_size, "E");
} break;
case TimelineEvent::kCounter: {
if (event->arguments_length() > 0) {
// We only report the first counter value.
length = OS::SNPrint(buffer, buffer_size, "C|%" Pd64 "|%s|%s", pid,
event->label(), event->arguments()[0].value);
}
}
default:
// Ignore event types that we cannot serialize to the Systrace format.
break;
}
return length;
}
void TimelineEventSystraceRecorder::CompleteEvent(TimelineEvent* event) {
if (event == NULL) {
return;
}
if (systrace_fd_ >= 0) {
// Serialize to the systrace format.
const intptr_t kBufferLength = 1024;
char buffer[kBufferLength];
const intptr_t event_length =
PrintSystrace(event, &buffer[0], kBufferLength);
if (event_length > 0) {
ssize_t result;
// Repeatedly attempt the write while we are being interrupted.
do {
result = write(systrace_fd_, buffer, event_length);
} while ((result == -1L) && (errno == EINTR));
}
}
ThreadBlockCompleteEvent(event);
}
TimelineEventPlatformRecorder::TimelineEventPlatformRecorder(intptr_t capacity)
: TimelineEventFixedBufferRecorder(capacity) {}
TimelineEventPlatformRecorder::~TimelineEventPlatformRecorder() {}
TimelineEventPlatformRecorder*
TimelineEventPlatformRecorder::CreatePlatformRecorder(intptr_t capacity) {
return new TimelineEventSystraceRecorder(capacity);
}
const char* TimelineEventPlatformRecorder::name() const {
return "Systrace";
}
TimelineEventBlock* TimelineEventPlatformRecorder::GetNewBlockLocked() {
// TODO(johnmccutchan): This function should only hand out blocks
// which have been marked as finished.
if (block_cursor_ == num_blocks_) {
block_cursor_ = 0;
}
TimelineEventBlock* block = &blocks_[block_cursor_++];
block->Reset();
block->Open();
return block;
}
void TimelineEventPlatformRecorder::CompleteEvent(TimelineEvent* event) {
UNREACHABLE();
}
} // namespace dart
#endif // defined(HOST_OS_LINUX) && !defined(PRODUCT)