structmy_data data; if(kfifo_is_empty(&my_fifo)){ return0;// 如果 FIFO 空,返回 0 表示没有数据可读 } kfifo_out(&my_fifo,&data,sizeof(data)); if(copy_to_user(buffer,&data,sizeof(data))){ return-EFAULT;// 返回错误,如果向用户空间复制失败 } returnsizeof(data);// 返回读取的字节...
kfifo_is_empty(__tmp); \if(__ret) { \*(typeof(__tmp->type))__val =\ (__is_kfifo_ptr(__tmp)?\ ((typeof(__tmp->type))__kfifo->data) : \ (__tmp->buf) \ )[__kfifo->out& __tmp->kfifo.mask]; \ smp_wmb(); \ __kfifo->out++; \ } \ } \ __ret; \ }) \...
* kfifo_is_empty - returns true if the fifo is empty * @fifo: the fifo to be used.*/staticinlineintkfifo_is_empty(structkfifo *fifo) {returnfifo->in== fifo->out; }/** * kfifo_is_full - returns true if the fifo is full * @fifo: the fifo to be used.*/staticinlineintkfifo_...
// 清空当前 FIFO(可选) while(!kfifo_is_empty(&node->fifo)){ charbuffer[32]; unsignedintread_bytes=kfifo_out(&node->fifo,buffer,sizeof(buffer)-1); buffer[read_bytes]='\0';// 确保字符串结束符 printk(KERN_INFO"Read from fifo: %s\n",buffer); } // 从链表中删除节点并释放资源 list...
static int fifo_pop(struct kfifo *fifo, u64 *addr) { int ret = 0; if (kfifo_is_empty(fifo)) { return -1; } /* pop member out */ ret = kfifo_out(fifo, addr, sizeof(*addr)); if (ret != sizeof(*addr)) { return -1; } return 0; }...
unsignedintkfifo_len(structkfifo*fifo); 1. 获取fifo总大小: AI检测代码解析 unsignedintkfifo_size(structkfifo*fifo); 1. 检查kfifo是否为空: AI检测代码解析 intkfifo_is_empty(structkfifo*fifo); 1. 检查kfifo是否为满: AI检测代码解析 intkfifo_is_full(structkfifo*fifo); 1....
* optimization: if the FIFO is empty, set the indices to 0 * so we don't wrap the next time */ if (fifo->in == fifo->out) fifo->in = fifo->out = 0; spin_unlock_irqrestore(fifo->lock, flags); return ret; } 问题:当数据写入速度大于读取速度的时候,in和out的值将永远不会相等...
* optimization: if the FIFO is empty, set the indices to 0 * so we don't wrap the next time */ if (fifo->in == fifo->out) fifo->in = fifo->out = 0; spin_unlock_irqrestore(fifo->lock, flags); return ret; } 1. 2. ...
在改变读写指针的时候,应该是原子操作。这要求仅通过读写指针的关系来判断剩余空间长度,而不是用一个变量来记录已使用长度。(更详细解释,可以看这个博主...
cout <<"Empty:"<< fifo.isEmpty() << endl; cout <<"Left Space:"<< fifo.left() << endl; cout <<"Length:"<< fifo.length() << endl; cout <<"==="<< endl; fifo.put(output,100); cout <<"Empty:"<< fifo.isEmpty() << endl;autod...