我在c ++中实现了多任务应用程序。生产者推送队列，消费者从队列中获取元素。有时我的应用程序崩溃了。有人可以帮我解决这个问题。 SF
Valgrind输出：
==10769== Memcheck, a memory error detector
==10769== Copyright (C) 2002-2013, and GNU GPL'd, by Julian Seward et al.
==10769== Using Valgrind-3.9.0 and LibVEX; rerun with -h for copyright info
==10769== Command: ./tachyon -s /HOME_ann/BII/biidurgak/test_new_tachyon/Tachyon_v5_improvedQueryTime/settings_smallNR
==10769==
==10769== Thread 5:
==10769== Invalid read of size 4
==10769== at 0x342669C9DE: std::string::assign(std::string const&) (in /usr/lib64/libstdc++.so.6.0.8)
==10769== by 0x42E01A: std::pair::operator=(std::pair const&) (stl_pair.h:152)
==10769== by 0x42B27A: boost::lockfree::detail::ringbuffer_base >::pop(std::pair&, std::pair*, unsigned
long) (spsc_queue.hpp:154)
==10769== by 0x428719: boost::lockfree::detail::compile_time_sized_ringbuffer, 2ul>::pop(std::pair&) (spsc_queue.hpp:305)
==10769== by 0x425DEA: boost::lockfree::spsc_queue, boost::lockfree::capacity, boost::parameter::void_>::pop(std::pair&) (spsc_queue.hpp:572)
==10769== by 0x41BE16: findInDatabase() (Tachyon.cpp:103)
==10769== by 0x4351D4: boost::detail::thread_data::run() (thread.hpp:117)
==10769== by 0x4E53D01: thread_proxy (in /HOME_ann/BII/biidurgak/test_new_tachyon/boost_install/boost_1_55_0/lib/libboost_thread.so.1.55.0)
==10769== by 0x342120673C: start_thread (in /lib64/libpthread-2.5.so)
==10769== by 0x34206D3D1C: clone (in /lib64/libc-2.5.so)
==10769== Address 0xfffffffffffffff8 is not stack'd, malloc'd or (recently) free'd
==10769==
==10769==
==10769== Process terminating with default action of signal 11 (SIGSEGV)
==10769== Access not within mapped region at address 0xFFFFFFFFFFFFFFF8
==10769== at 0x342669C9DE: std::string::assign(std::string const&) (in /usr/lib64/libstdc++.so.6.0.8)
==10769== by 0x42E01A: std::pair::operator=(std::pair const&) (stl_pair.h:152)
==10769== by 0x42B27A: boost::lockfree::detail::ringbuffer_base >::pop(std::pair&, std::pair*, unsigned long) (spsc_queue.hpp:154)
==10769== by 0x428719: boost::lockfree::detail::compile_time_sized_ringbuffer, 2ul>::pop(std::pair&) (spsc_queue.hpp:305)
==10769== by 0x425DEA: boost::lockfree::spsc_queue, boost::lockfree::capacity, boost::parameter::void_>::pop(std::pair&) (spsc_queue.hpp:572)
==10769== by 0x41BE16: findInDatabase() (Tachyon.cpp:103)
==10769== by 0x4351D4: boost::detail::thread_data::run() (thread.hpp:117)
==10769== by 0x4E53D01: thread_proxy (in /HOME_ann/BII/biidurgak/test_new_tachyon/boost_install/boost_1_55_0/lib/libboost_thread.so.1.55.0)
==10769== by 0x342120673C: start_thread (in /lib64/libpthread-2.5.so)
==10769== by 0x34206D3D1C: clone (in /lib64/libc-2.5.so)
==10769== If you believe this happened as a result of a stack
==10769== overflow in your program's main thread (unlikely but
==10769== possible), you can try to increase the size of the
==10769== main thread stack using the --main-stacksize= flag.
==10769== The main thread stack size used in this run was 10485760.
==10769==
==10769== HEAP SUMMARY:
==10769== in use at exit: 219,895,341 bytes in 4,598,508 blocks
==10769== total heap usage: 36,680,650 allocs, 32,082,142 frees, 1,474,244,383 bytes allocated
==10769==
==10769== LEAK SUMMARY:
==10769== definitely lost: 1,904 bytes in 2 blocks
==10769== indirectly lost: 0 bytes in 0 blocks
==10769== possibly lost: 184,232,229 bytes in 4,598,462 blocks
==10769== still reachable: 35,661,208 bytes in 44 blocks
==10769== suppressed: 0 bytes in 0 blocks
==10769== Rerun with --leak-check=full to see details of leaked memory
==10769==
==10769== For counts of detected and suppressed errors, rerun with: -v
制片：
void producer(string file) {
ifstream query(file.c_str());
string description = "";
string sequence = "";
string line;
while (getline(query, line)) {
//read description
if (line == "") continue;
if (line.at(0) == '>') {
if (sequence != "") {
pair<string, string> a = make_pair(description, sequence);
while (!queue.push(a))
;
sequence = "";
}
description = line.substr(1);
} else {
sequence += line;
}
}
if (sequence != "" && description != "") {
pair<string, string> a = make_pair(description, sequence);
while (!queue.push(a))
;
}
}
在消费者中我有这个：
void Consumer(void) {
pair<string, string>element;
//part of code
while(queue.pop(element)){ //Line 103 in Tachyon.cpp
string queryDescription = element.first;
string sequence = element.second;
//Part of code
}
}
队列是全局变量：
boost::lockfree::spsc_queue<pair<string, string>, boost::lockfree::capacity<2> > queue;
答案 0 :(得分：0)
全局变量，多个线程（我假设），一个读取和另一个线程写入 - 您需要一个同步对象，如互斥或临界区。
伪代码：
// Consumer
loop-begin;
Lock();
get-item-into-local-variable
Unlock();
process-local-variable-item;
loop-end
// Producer
void AddItem(item)
{
Lock();
Add-item-into-queue
Unlock();
}