infernap12/jdk
1
0
Fork 0
mirror of https://github.com/openjdk/jdk.git synced 2026-02-02 06:28:23 +00:00
Code Issues Packages Projects Releases Wiki Activity

8317432: Async UL: Use memcpy instead of strcpy in Message ctr

Browse Source 
Reviewed-by: xliu, dholmes
This commit is contained in:
Johan Sjölen 2023-10-13 11:28:17 +00:00
parent 126f2ace5d
commit e490cf9c65
2 changed files with 17 additions and 9 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
src/hotspot/share/logging/logAsyncWriter.cpp
View File

@ -1,5 +1,6 @@
/*
* Copyright Amazon.com Inc. or its affiliates. All Rights Reserved.
* Copyright (c) 2023, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
@ -48,13 +49,14 @@ const LogDecorations& AsyncLogWriter::None = LogDecorations(LogLevel::Warning, L
LogDecorators::None);
bool AsyncLogWriter::Buffer::push_back(LogFileStreamOutput* output, const LogDecorations& decorations, const char* msg) {
const size_t sz = Message::calc_size(strlen(msg));
const size_t len = strlen(msg);
const size_t sz = Message::calc_size(len);
const bool is_token = output == nullptr;
// Always leave headroom for the flush token. Pushing a token must succeed.
const size_t headroom = (!is_token) ? Message::calc_size(0) : 0;
if (_pos + sz <= (_capacity - headroom)) {
new(_buf + _pos) Message(output, decorations, msg);
new(_buf + _pos) Message(output, decorations, msg, len);
_pos += sz;
return true;
}

20
src/hotspot/share/logging/logAsyncWriter.hpp
View File

@ -1,5 +1,6 @@
/*
* Copyright Amazon.com Inc. or its affiliates. All Rights Reserved.
* Copyright (c) 2023, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
@ -66,13 +67,13 @@ class AsyncLogWriter : public NonJavaThread {
uint32_t, 17, /*table_size*/
ALLOC_TYPE, mtLogging>;
// Messsage is the envelop of a log line and its associative data.
// Messsage is the envelope of a log line and its associative data.
// Its length is variable because of the zero-terminated c-str. It is only valid when we create it using placement new
// within a buffer.
//
// Example layout:
// ---------------------------------------------
// |_output|_decorations|"a log line", |pad| <- pointer aligned.
// |_output|_decorations|"a log line", |pad| <- Message aligned.
// |_output|_decorations|"yet another",|pad|
// ...
// |nullptr|_decorations|"",|pad| <- flush token
@ -84,16 +85,16 @@ class AsyncLogWriter : public NonJavaThread {
LogFileStreamOutput* const _output;
const LogDecorations _decorations;
public:
Message(LogFileStreamOutput* output, const LogDecorations& decorations, const char* msg)
// msglen excludes NUL-byte
Message(LogFileStreamOutput* output, const LogDecorations& decorations, const char* msg, const size_t msglen)
: _output(output), _decorations(decorations) {
assert(msg != nullptr, "c-str message can not be null!");
PRAGMA_STRINGOP_OVERFLOW_IGNORED
strcpy(reinterpret_cast<char* >(this+1), msg);
memcpy(reinterpret_cast<char* >(this+1), msg, msglen + 1);
}
// Calculate the size for a prospective Message object depending on its message length including the trailing zero
static constexpr size_t calc_size(size_t message_len) {
return align_up(sizeof(Message) + message_len + 1, sizeof(void*));
return align_up(sizeof(Message) + message_len + 1, alignof(Message));
}
size_t size() const {
@ -114,6 +115,8 @@ class AsyncLogWriter : public NonJavaThread {
public:
Buffer(size_t capacity) : _pos(0), _capacity(capacity) {
_buf = NEW_C_HEAP_ARRAY(char, capacity, mtLogging);
// Ensure _pos is Message-aligned
_pos = align_up(_buf, alignof(Message)) - _buf;
assert(capacity >= Message::calc_size(0), "capcity must be great a token size");
}
@ -124,7 +127,10 @@ class AsyncLogWriter : public NonJavaThread {
void push_flush_token();
bool push_back(LogFileStreamOutput* output, const LogDecorations& decorations, const char* msg);
void reset() { _pos = 0; }
void reset() {
// Ensure _pos is Message-aligned
_pos = align_up(_buf, alignof(Message)) - _buf;
}
class Iterator {
const Buffer& _buf;