我正在尝试为x64上的Linux 3.10.45构建内核模块(用于硬件的压力测试工具)。 到目前为止,它似乎工作正常,直到添加互斥。内核模块将不会链接 - 符号mutex_lock_nested未找到
我添加了互斥使用和函数mutex_init,mutex_lock,mutex_unlock和mutex_destroy。
构建模块产生任何错误或警告,但“insmod的”加载的时候,也有dmesg的错误信息:
[76603.744551] tryBlk: Unknown symbol mutex_lock_nested (err 0)
[76603.744574] tryBlk: Unknown symbol mutex_destroy (err 0)
我发现了一个暗示,与“未知符号”,它有时帮助添加MODULE_LICENSE(“GPL v2”)行。
没有区别。
看着linux/mutex.h,我发现如果定义了符号CONFIG_DEBUG_LOCK_ALLOC,mutex_lock只会定义为mutex_lock_nested。检查这个,它似乎是在我的.config中定义的。 (不记得去碰它,它基本上只是kernel.org的一个内核,已经建成了)。
这有问题吗?我是否需要手动添加其他内容到我的模块中,以便使用此调试功能构建它?
试图改变包含文件和序列。没有不同。
系统运行Debian-7'Wheezy'x64,内核更改为3.10.45。
使用互斥的文件:
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/mutex.h>
#include <linux/vmalloc.h>
#include <linux/uaccess.h>
#include "ring.h"
struct RingBuf
{
unsigned char *buffer;
unsigned int size;
unsigned int inp,outp;
struct mutex mtx;
};
static int _bytesavail(struct RingBuf *self);
static int _spaceavail(struct RingBuf *self);
struct RingBuf *RingBuf_init(unsigned int size)
{
struct RingBuf *self;
if(size<16)size=16;
if(size>0x10000000u)return 0;
if(size & (size-1))
{
unsigned int ns;
// is not a power of 2.
size = size<<1;
while(1)
{
ns=size&(size-1);
if(!ns)break;
size=ns;
}
}
self = (struct RingBuf*)vmalloc(sizeof(*self)+size);
memset(self , 0 , sizeof(*self));
self->buffer = (unsigned char*)(self+1);
self->size = size;
self->inp = 0;
self->outp = 0;
mutex_init(&(self->mtx));
return self;
}
void RingBuf_uninit(struct RingBuf *self)
{
if(!self)return;
mutex_lock(&(self->mtx));
mutex_destroy(&(self->mtx));
memset(self , 0xFE , sizeof(*self));
vfree(self);
}
int RingBuf_add(struct RingBuf *self,const void *data,int num)
{
int cpy;
if(num<=0)return 0;
mutex_lock(&(self->mtx));
// check amount to copy
cpy = _spaceavail(self);
if(cpy>num)cpy=num;
// one part or split
if(self->inp+cpy <= self->size)
{
// one chunk
memcpy(self->buffer+self->inp , data , cpy);
}else{
int p1 = (self->size-self->inp);
// wrapped
memcpy(self->buffer+self->inp , data , p1);
memcpy(self->buffer , ((const unsigned char*)data)+p1 , cpy-p1);
}
self->inp = (self->inp+cpy) & (self->size-1) ;
mutex_unlock(&(self->mtx));
return cpy;
}
int RingBuf_get(struct RingBuf *self,void *data,int num)
{
int cpy;
if(num<=0)return 0;
mutex_lock(&(self->mtx));
// check amount to copy
cpy = _bytesavail(self);
if(cpy>num)cpy=num;
// one part or split
if(self->outp+cpy <= self->size)
{
// one chunk
memcpy(data , self->buffer+self->outp , cpy);
}else{
int p1 = (self->size-self->outp);
// wrapped
memcpy(data , self->buffer+self->outp , p1);
memcpy(((unsigned char*)data)+p1 , self->buffer , cpy-p1);
}
self->outp = (self->outp+cpy) & (self->size-1) ;
mutex_unlock(&(self->mtx));
return cpy;
}
int RingBuf_get_user(struct RingBuf *self,void __user *data,int num)
{
int cpy;
int ret;
if(num<=0)return 0;
mutex_lock(&(self->mtx));
// check amount to copy
cpy = _bytesavail(self);
if(cpy>num)cpy=num;
// one part or split
if(self->outp+cpy <= self->size)
{
// one chunk
ret = copy_to_user(data , self->buffer+self->outp , cpy);
}else{
int p1 = (self->size-self->outp);
// wrapped
ret = copy_to_user(data , self->buffer+self->outp , p1);
if(!ret)
ret = copy_to_user(((unsigned char*)data)+p1 , self->buffer , cpy-p1);
}
if(ret)return -1;
self->outp = (self->outp+cpy) & (self->size-1) ;
mutex_unlock(&(self->mtx));
return cpy;
}
int RingBuf_numBytes(struct RingBuf *self)
{
int result;
mutex_lock(&(self->mtx));
result = _bytesavail(self);
mutex_unlock(&(self->mtx));
return result;
}
static int _bytesavail(struct RingBuf *self)
{
return (self->inp-self->outp)&(self->size-1);
}
static int _spaceavail(struct RingBuf *self)
{
return (self->outp-self->inp-1)&(self->size-1);
}