platform_system_core/logd/ChattyLogBuffer.h

101 lines
3.9 KiB
C++

/*
* Copyright (C) 2012-2014 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.
*/
#pragma once
#include <sys/types.h>
#include <list>
#include <optional>
#include <string>
#include <android-base/thread_annotations.h>
#include <android/log.h>
#include <private/android_filesystem_config.h>
#include <sysutils/SocketClient.h>
#include "LogBuffer.h"
#include "LogBufferElement.h"
#include "LogReaderList.h"
#include "LogReaderThread.h"
#include "LogStatistics.h"
#include "LogTags.h"
#include "LogWhiteBlackList.h"
#include "LogWriter.h"
#include "rwlock.h"
typedef std::list<LogBufferElement> LogBufferElementCollection;
class ChattyLogBuffer : public LogBuffer {
LogBufferElementCollection mLogElements GUARDED_BY(lock_);
// watermark of any worst/chatty uid processing
typedef std::unordered_map<uid_t, LogBufferElementCollection::iterator> LogBufferIteratorMap;
LogBufferIteratorMap mLastWorst[LOG_ID_MAX] GUARDED_BY(lock_);
// watermark of any worst/chatty pid of system processing
typedef std::unordered_map<pid_t, LogBufferElementCollection::iterator> LogBufferPidIteratorMap;
LogBufferPidIteratorMap mLastWorstPidOfSystem[LOG_ID_MAX] GUARDED_BY(lock_);
unsigned long mMaxSize[LOG_ID_MAX] GUARDED_BY(lock_);
public:
ChattyLogBuffer(LogReaderList* reader_list, LogTags* tags, PruneList* prune,
LogStatistics* stats);
~ChattyLogBuffer();
void Init() override;
int Log(log_id_t log_id, log_time realtime, uid_t uid, pid_t pid, pid_t tid, const char* msg,
uint16_t len) override;
uint64_t FlushTo(
LogWriter* writer, uint64_t start, pid_t* lastTid,
const std::function<FlushToResult(const LogBufferElement* element)>& filter) override;
bool Clear(log_id_t id, uid_t uid = AID_ROOT) override;
unsigned long GetSize(log_id_t id) override;
int SetSize(log_id_t id, unsigned long size) override;
private:
void maybePrune(log_id_t id) REQUIRES(lock_);
void kickMe(LogReaderThread* me, log_id_t id, unsigned long pruneRows) REQUIRES_SHARED(lock_);
bool prune(log_id_t id, unsigned long pruneRows, uid_t uid = AID_ROOT) REQUIRES(lock_);
LogBufferElementCollection::iterator erase(LogBufferElementCollection::iterator it,
bool coalesce = false) REQUIRES(lock_);
bool ShouldLog(log_id_t log_id, const char* msg, uint16_t len);
void Log(LogBufferElement&& elem) REQUIRES(lock_);
// Returns an iterator to the oldest element for a given log type, or mLogElements.end() if
// there are no logs for the given log type. Requires mLogElementsLock to be held.
LogBufferElementCollection::iterator GetOldest(log_id_t log_id) REQUIRES(lock_);
LogReaderList* reader_list_;
LogTags* tags_;
PruneList* prune_;
LogStatistics* stats_;
// Keeps track of the iterator to the oldest log message of a given log type, as an
// optimization when pruning logs. Use GetOldest() to retrieve.
std::optional<LogBufferElementCollection::iterator> oldest_[LOG_ID_MAX];
RwLock lock_;
// This always contains a copy of the last message logged, for deduplication.
std::optional<LogBufferElement> last_logged_elements_[LOG_ID_MAX] GUARDED_BY(lock_);
// This contains an element if duplicate messages are seen.
// Its `dropped` count is `duplicates seen - 1`.
std::optional<LogBufferElement> duplicate_elements_[LOG_ID_MAX] GUARDED_BY(lock_);
};