linux基于LD_PRELOAD机制的内存泄露检测工具

Valgrind影响性能且某些程序会报错,同时我们希望跳过初始化阶段,在程序稳定运行之后再去检测内存是否会持续增涨,为了更高效的记录内存分配情况,采用b+树.该程序会拦截malloc,free,calloc,realloc,new,delete。记录lr地址,方便解析脚本定位调用的代码位置.

1.测试DEMO

#include <stdio.h>
#include <stdlib.h>

int main()
{
    printf("Pree Enter Twice to PreMalloc\n");
    getchar(), getchar();
    char *p = (char *)calloc(1, 512);
    free(p);

    p = (char *)calloc(1, 512);
    free(p);

    p = (char *)calloc(1, 512);
    // free(p);

    p = (char *)calloc(1, 512);
    // free(p);

    p = (char *)calloc(1, 512);
    free(p);

    char *buf = new char[1280];
    printf("Pree Enter Twice to Test Malloc Free\n");
    getchar(), getchar();
    printf("TestOver\n");
}
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2.编译拦截程序及测试DEMO

make clean && make
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3.设置环境变量,运行DEMO程序

LD_PRELOAD=$PWD/libMemLeakTrackerPreload.so ./malloc_demo
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4.等DEMO稳定后,向DEMO发送USR2信号,开启内存泄露监测

killall -USR2 malloc_demo
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5.DEMO运行一段时间后,向DEMO发送USR1信号,将未释放的内存信息保存到memleak.txt中

killall -USR1 malloc_demo
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6.结合/proc/pid/maps和上面保存的memleak.txt,生成内存泄露报告(哪个位置分配了多少次,多少字节)

python3 parser.py /proc/`pidof malloc_demo`/maps memleak.txt
cat mem_leak_report.txt
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输出

------------------[INFO]Count:1 Total:1280(Byte)---------------------
/home/MemChecker/malloc_demo main /home/MemChecker/preload_demo.cpp:23
------------------[INFO]Count:1 Total:512(Byte)---------------------
/home/MemChecker/malloc_demo main /home/MemChecker/preload_demo.cpp:14
------------------[INFO]Count:1 Total:512(Byte)---------------------
/home/MemChecker/malloc_demo main /home/MemChecker/preload_demo.cpp:17
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