仅当存在打印时代码才能正确执行 (C)-6ren

仅当存在打印时代码才能正确执行 (C)

转载作者：行者123 更新时间：2023-11-30 14:36:41

我正在为 Zynq FPGA 的 DAQ 系统建立原型(prototype)。我通过以太网从服务器接收数据，使用 DMA 将其写入 FIFO，反之亦然，使用两个不同的 pthread。但是，只有执行 printf 时，线程才能正常工作。我预计存在内存泄漏或某些行导致未定义的行为，但我无法发现它。

将输出放置到 stderr 具有相同的结果。更改地址没有什么不同。

对于可耻的代码感到抱歉，但我现在尝试替换几乎每一行来发现问题。


#include <netdb.h> 
#include <stdio.h> 
#include <stdlib.h> 
#include <string.h> 
#include <sys/socket.h>
#include <stdio.h>
#include <unistd.h>
#include <fcntl.h>
#include <termios.h>
#include <sys/mman.h>
#include <arpa/inet.h>
#include <pthread.h>
#include <sys/stat.h>
#include <stdint.h>
#include <errno.h>
#include <time.h>

#define PORT 8080 
#define SA struct sockaddr

#define MM2S_CONTROL_REGISTER 0x00
#define MM2S_STATUS_REGISTER 0x04
#define MM2S_START_ADDRESS 0x18
#define MM2S_LENGTH 0x28

#define S2MM_CONTROL_REGISTER 0x30
#define S2MM_STATUS_REGISTER 0x34
#define S2MM_DESTINATION_ADDRESS 0x48
#define S2MM_LENGTH 0x58

#define VIRT_ADDR 0x40400000
#define FIFO_ADDR 0x0c000000
#define SEND_ADDR 0x0a000000
#define RECV_ADDR 0x0b000000

#define TIMEOUT 10
#define MAX_TRANSF 12274

unsigned int dma_set(unsigned int *dma_virtual_address, int offset, unsigned int value);
unsigned int dma_get(unsigned int *dma_virtual_address, int offset);
int dma_mm2s_sync(unsigned int *dma_virtual_address);
int dma_s2mm_sync(unsigned int *dma_virtual_address);
unsigned int dma_s2mm_status(unsigned int *dma_virtual_address);
unsigned int dma_mm2s_status(unsigned int *dma_virtual_address);
void memdump(void *virtual_address, int byte_count);
void print_status(unsigned int status);

unsigned long int elements = 0;
clock_t start_time;

typedef struct arg_struct {
    unsigned int *virtual_address;
    unsigned int *virtual_buffer;
    unsigned int *head;
    unsigned int *tail;
    unsigned int buffsize;
    unsigned int fifosize;
    unsigned int sockfd;
    pthread_mutex_t *lock;
    char verbose;
} arguments;

unsigned int dma_set(unsigned int *dma_virtual_address, int offset, unsigned int value) {
        dma_virtual_address[offset >> 2] = value;
}

unsigned int dma_get(unsigned int *dma_virtual_address, int offset) {
        return dma_virtual_address[offset >> 2];
}

int dma_mm2s_sync(unsigned int *dma_virtual_address) {
        unsigned int mm2s_status = dma_get(dma_virtual_address, MM2S_STATUS_REGISTER);
        while (!(mm2s_status & 1 << 12) || !(mm2s_status & 1 << 1)) {
                dma_s2mm_status(dma_virtual_address);
                dma_mm2s_status(dma_virtual_address);
                mm2s_status = dma_get(dma_virtual_address, MM2S_STATUS_REGISTER);
        }
}

int dma_s2mm_sync(unsigned int *dma_virtual_address) {
        unsigned int s2mm_status = dma_get(dma_virtual_address, S2MM_STATUS_REGISTER);
        while (!(s2mm_status & 1 << 12) || !(s2mm_status & 1 << 1)) {
                dma_s2mm_status(dma_virtual_address);
                dma_mm2s_status(dma_virtual_address);
                s2mm_status = dma_get(dma_virtual_address, S2MM_STATUS_REGISTER);
        }
}

unsigned int dma_s2mm_status(unsigned int *dma_virtual_address) {
        return dma_get(dma_virtual_address, S2MM_STATUS_REGISTER);
}

unsigned int dma_mm2s_status(unsigned int *dma_virtual_address) {
        return dma_get(dma_virtual_address, MM2S_STATUS_REGISTER);
}

void print_mm2s_status(unsigned int status) {
    fprintf(stderr, "[*] Stream to memory-mapped status (0x%08x@0x%02x):", status, S2MM_STATUS_REGISTER);
    print_status(status);
}

void print_s2mm_status(unsigned int status) {
    fprintf(stderr, "[*] Memory-mapped to stream status (0x%08x@0x%02x):", status, MM2S_STATUS_REGISTER);
    print_status(status);
}

void print_status(unsigned int status) {
    if (status & 0x00000001) fprintf(stderr, " halted");
    else fprintf(stderr, " running");
    if (status & 0x00000002) fprintf(stderr, " idle");
    if (status & 0x00000008) fprintf(stderr, " SGIncld");
    if (status & 0x00000010) fprintf(stderr, " DMAIntErr");
    if (status & 0x00000020) fprintf(stderr, " DMASlvErr");
    if (status & 0x00000040) fprintf(stderr, " DMADecErr");
    if (status & 0x00000100) fprintf(stderr, " SGIntErr");
    if (status & 0x00000200) fprintf(stderr, " SGSlvErr");
    if (status & 0x00000400) fprintf(stderr, " SGDecErr");
    if (status & 0x00001000) fprintf(stderr, " IOC_Irq");
    if (status & 0x00002000) fprintf(stderr, " Dly_Irq");
    if (status & 0x00004000) fprintf(stderr, " Err_Irq");
    fprintf(stderr, "\n");
}

void memdump(void *virtual_address, int byte_count) {
        char * p = virtual_address;
        int offset;
        for (offset = 0; offset < byte_count; offset++) {
                fprintf(stderr, "%02x", p[offset]);
                if (offset % 4 == 3) {
                        fprintf(stderr, " ");
                }
        }
}

void DMATransfer(unsigned int *virtual_address, long unsigned int src, long unsigned int dest, unsigned int length, char verbose) {

    unsigned int s2mm_status = 0;
    unsigned int mm2s_status = 0;

        dma_set(virtual_address, S2MM_CONTROL_REGISTER, 4);
        dma_set(virtual_address, MM2S_CONTROL_REGISTER, 4);

    if (verbose > 0) {
        print_s2mm_status(dma_s2mm_status(virtual_address));
        print_mm2s_status(dma_mm2s_status(virtual_address));
    }

        dma_set(virtual_address, S2MM_CONTROL_REGISTER, 0);
        dma_set(virtual_address, MM2S_CONTROL_REGISTER, 0);

    if (verbose > 0) {
        print_s2mm_status(dma_s2mm_status(virtual_address));
        print_mm2s_status(dma_mm2s_status(virtual_address));
    }

    dma_set(virtual_address, S2MM_DESTINATION_ADDRESS, dest);
    dma_set(virtual_address, MM2S_START_ADDRESS, src);

    if (verbose > 0) {
        print_s2mm_status(dma_s2mm_status(virtual_address));
        print_mm2s_status(dma_mm2s_status(virtual_address));
    }

    dma_set(virtual_address, S2MM_CONTROL_REGISTER, 0xf001);
    dma_set(virtual_address, MM2S_CONTROL_REGISTER, 0xf001);

    if (verbose > 0) {
        print_s2mm_status(dma_s2mm_status(virtual_address));
        print_mm2s_status(dma_mm2s_status(virtual_address));
    }

    dma_set(virtual_address, S2MM_LENGTH, length);
    dma_set(virtual_address, MM2S_LENGTH, length);

    if (verbose > 0) {
        print_s2mm_status(dma_s2mm_status(virtual_address));
        print_mm2s_status(dma_mm2s_status(virtual_address));
    }

    dma_mm2s_sync(virtual_address);
    dma_s2mm_status(virtual_address);

    if (verbose > 0) {
        print_s2mm_status(dma_s2mm_status(virtual_address));
        print_mm2s_status(dma_mm2s_status(virtual_address));
    }

}

int GetCPULoad() {

    int FileHandler;
    char FileBuffer[1024];
    float load;

    FileHandler = open("/proc/loadavg", O_RDONLY);
    if(FileHandler < 0) {
        return -1;
    }
    read(FileHandler, FileBuffer, sizeof(FileBuffer) - 1);
    sscanf(FileBuffer, "%f", &load);
    close(FileHandler);
    return (int)(load * 100);

}

void *sender(void *params) {

    arguments *args = params;

    if (args->head == NULL) {
        fprintf(stderr, "[-] Head pointer not valid\n");
        exit(0);
    }
    if (args->tail == NULL) {
        fprintf(stderr, "[-] Tail pointer not valid\n");
        exit(0);
    }
    if (args->virtual_address == NULL) {
        fprintf(stderr, "[-] AXI DMA register pointer not valid\n");
        exit(0);
    }
    if (args->virtual_buffer == NULL) {
        fprintf(stderr, "[-] Send buffer pointer not valid\n");
        exit(0);
    }

    unsigned long int units_sent = 0;
    unsigned int myhead = 0;
    unsigned int mytail = 0;

    for (;;) {
        pthread_mutex_lock(args->lock);
        myhead = *(args->head);
        mytail = *(args->tail);
        pthread_mutex_unlock(args->lock);
        fprintf(stderr, "[*] Send   Head: %d    Tail: %d\n", myhead, mytail);
        if (myhead != mytail) {
            int remaining = args->buffsize;
            int sent = 0;
            int src = FIFO_ADDR + mytail * args->buffsize;
            if (args->verbose > 2) {
                fprintf(stderr, "[*] Sender: DMA is transferring data from 0x%x to 0x%x\n", src, SEND_ADDR);
            }
            unsigned int length = args->buffsize;
            unsigned int verb = args->verbose > 2 ? 1 : 0;
            pthread_mutex_lock(args->lock);
            while (remaining > 0) {
                length = remaining < MAX_TRANSF ? remaining : remaining % MAX_TRANSF;
                DMATransfer(args->virtual_address, src + sent, SEND_ADDR, length, verb);
                remaining -= args->buffsize;
                sent += remaining;
            }
            pthread_mutex_unlock(args->lock);
            elements--;
            units_sent++;
            if (args->verbose > 2) {
                fprintf(stderr, "[*] %f elements in FIFO: %lu\n", ((double)(clock() - start_time)) / CLOCKS_PER_SEC, elements);
                fprintf(stderr, "[*] %f DMA tranfer to buffer: %d\n", ((double)(clock() - start_time)) / CLOCKS_PER_SEC, units_sent);
            }
            remaining = args->buffsize;
            sent = 0;
            int result = 0;
            pthread_mutex_lock(args->lock);
            while (remaining > 0) {
                    result = send(args->sockfd, args->virtual_buffer + sent, remaining, 0);
                    if (result > 0) {
                        remaining -= result;
                        sent += remaining;
                    } else if (result < 0) {
                        fprintf(stderr, "[-] Error retrieving configuration from the server\n");
                    exit(0);
                    }
            }
            *(args->tail) = (mytail + 1) % (args->fifosize + 1);
            pthread_mutex_unlock(args->lock);
            //memset(args->virtual_buffer, 0, args->buffsize);
            if (args->verbose > 2) {
                fprintf(stderr, "[*] %f Unit sent: %d\n", ((double)(clock() - start_time)) / CLOCKS_PER_SEC, units_sent);
            }
            if (args->verbose > 0) {
                fprintf(stderr, "[*] Packet retrieved");
            }
            if (args->verbose > 1) {
                fprintf(stderr, " content: ");
                memdump(args->virtual_buffer, args->buffsize);
            }
            if (args->verbose > 0) {
                fprintf(stderr, "\n");
            }
            if (args->verbose > 2) {
                fprintf(stderr, "[*] %f CPU Usage: %d\n", ((double)(clock() - start_time)) / CLOCKS_PER_SEC, GetCPULoad());
            }
        }
        printf("0000000000000000000000000\n");
    }

}

void *receiver(void *params) {

    arguments *args = params;

    if (args->head == NULL) {
        fprintf(stderr, "[-] Head pointer not valid\n");
        exit(0);
    }
    if (args->tail == NULL) {
        fprintf(stderr, "[-] Tail pointer not valid\n");
        exit(0);
    }
    if (args->virtual_address == NULL) {
        fprintf(stderr, "[-] AXI DMA register pointer not valid\n");
        exit(0);
    }
    if (args->virtual_buffer == NULL) {
        fprintf(stderr, "[-] Recv buffer pointer not valid\n");
        exit(0);
    }

    unsigned long int units_received = 0;
    unsigned int myhead = 0;
    unsigned int mytail = 0;

    for (;;) {
        pthread_mutex_lock(args->lock);
        myhead = *(args->head);
        mytail = *(args->tail);
        pthread_mutex_unlock(args->lock);
        fprintf(stderr, "[*] Recv   Head: %d    Tail: %d\n", myhead, mytail);
        if (mytail != myhead + 1) {
            int remaining = args->buffsize;
            int received = 0;
            int result = 0;
            pthread_mutex_lock(args->lock);
            while (remaining > 0) {
                    result = recv(args->sockfd, args->virtual_buffer + received, remaining, 0);
                fprintf(stderr, "[*] Recv result: %d\n", result); 
                    if (result > 0) {
                        remaining -= result;
                        received += result;
                    } else if (result == 0) {
                        fprintf(stderr, "[-] Remote side closed his end of the connection before all data was received\n");
                        exit(0);
                    } else if (result < 0) {
                        fprintf(stderr, "[-] Error retrieving configuration from the server\n");
                    exit(0);
                    }
            }
            printf("++++++++++++++++++++++++++++\n");
            pthread_mutex_unlock(args->lock);
            units_received++;
            if (args->verbose > 2) {
                fprintf(stderr, "[*] %f Unit recv: %d\n", ((double)(clock() - start_time)) / CLOCKS_PER_SEC, units_received);
            }
            remaining = args->buffsize;
            received = 0;
            int dest = FIFO_ADDR + myhead * args->buffsize;
            if (args->verbose > 2) {
                fprintf(stderr, "[*] Receiver: DMA is transferring data from 0x%x to 0x%x\n", RECV_ADDR, dest);
            }
            unsigned int length = args->buffsize;
            unsigned int verb = args->verbose > 2 ? 1 : 0;
            pthread_mutex_lock(args->lock);
            while (remaining > 0) {
                printf("############################\n");
                length = remaining < MAX_TRANSF ? remaining : remaining % MAX_TRANSF;
                DMATransfer(args->virtual_address, RECV_ADDR, dest + received, length, verb);
                remaining -= args->buffsize;
                received += args->buffsize;
            }
            printf("*************************\n");
            *(args->head) = (myhead + 1) % (args->fifosize + 1);
            pthread_mutex_unlock(args->lock);
            //memset(args->virtual_buffer, 0, args->buffsize);
            elements++;
            if (args->verbose > 2) {
                fprintf(stderr, "[*] %f elements in FIFO: %lu\n", ((double)(clock() - start_time)) / CLOCKS_PER_SEC, elements);
                fprintf(stderr, "[*] %f DMA tranfer to DDR: %d\n", ((double)(clock() - start_time)) / CLOCKS_PER_SEC, units_received);
            }
            if (args->verbose > 0) {
                fprintf(stderr, "[*] Packet received");
            }
            if (args->verbose > 1) {
                fprintf(stderr, " content: ");
                memdump(args->virtual_buffer, args->buffsize);
            }
            if (args->verbose > 0) {
                fprintf(stderr, "\n");
            }
            if (args->verbose > 2) {
                fprintf(stderr, "[*] %f CPU Usage: %d\n", ((double)(clock() - start_time)) / CLOCKS_PER_SEC, GetCPULoad());
            }
        }
        printf("77777777777777777777777777777\n");
    }

}

int isValidIpAddress(char *ipAddress) {

    struct sockaddr_in sa;
    int result = inet_pton(AF_INET, ipAddress, &(sa.sin_addr));
    if (result != 0) {
        return 0;
    } else {
        return 1;
    }

}

int main(int argc, char *argv[]) {

        if (argc < 3 || argc > 5) {
                fprintf(stderr, "\nUsage: DAQTest [IP address] [fifo size]\nExample: DAQTest 192.168.1.81 64\n\n");
        fprintf(stderr, "Optional flags:    -v  Verbose (print operations)\n");
        fprintf(stderr, "       -vv Very verbose (also print data content)\n");
        fprintf(stderr, "       -vvv    Extremely verbose (also print DMA info)\n\n");
                exit(0);
        }
    if (isValidIpAddress(argv[1]) == 1) {
        fprintf(stderr, "[-] Invalid ip address\n");
        exit(0);
    }
        int fifosize = atoi(argv[2]);
        if (fifosize < 0 || fifosize > 8192) {
                fprintf(stderr, "[-] Invalid fifo size\n");
                exit(0);
        }

    char verbose = 0;
    if (argc == 4) {
        if (strcmp(argv[3], "-v") == 0) {
            verbose = 1;
        } else if (strcmp(argv[3], "-vv") == 0) {
            verbose = 2;
        } else if (strcmp(argv[3], "-vvv") == 0) {
            verbose = 3;
        } else {
            fprintf(stderr, "[-] Unwanted parameter\n");
            exit(0);
        }
    }

        struct sockaddr_in servaddr, cli;

        int sockfd = socket(AF_INET, SOCK_STREAM, 0);
        if (-1 == sockfd) {
                fprintf(stderr, "[-] Socket creation failed\n");
                exit(0);
        }
        bzero(&servaddr, sizeof(servaddr));

        servaddr.sin_family = AF_INET;
        servaddr.sin_addr.s_addr = inet_addr(argv[1]);
        servaddr.sin_port = htons(PORT);

    /*
    struct timeval tv;
    tv.tv_sec = TIMEOUT;
    tv.tv_usec = 0;
    setsockopt(sockfd, SOL_SOCKET, SO_RCVTIMEO, (const char*)&tv, sizeof tv);
    */

        if (connect(sockfd, (SA * ) & servaddr, sizeof(servaddr)) != 0) {
                fprintf(stderr, "[-] Connection failed\n");
                exit(0);
        }

    fprintf(stderr, "[+] Connected to the server\n");

    int buffsize = 0;
    char* recv_buffer = (char*)&buffsize;
    int remaining = sizeof(int);
    int received = 0;
    int result = 0;
    while (remaining > 0) {
            result = recv(sockfd, recv_buffer + received, remaining, 0);
            if (result > 0) {
                remaining -= result;
                received += result;
            } else if (result == 0) {
                fprintf(stderr, "[-] Remote side closed his end of the connection before all data was received\n");
                exit(0);
            } else if (result < 0) {
                fprintf(stderr, "[-] Error retrieving configuration from the server\n");
            exit(0);
            }
    }

    //fprintf(stderr, "[*] Page size: %ld\n", sysconf(_SC_PAGE_SIZE));

        int dh = open("/dev/mem", O_RDWR | O_SYNC);

        unsigned int *virtual_address = mmap(NULL, 65535, PROT_READ | PROT_WRITE, MAP_SHARED, dh, VIRT_ADDR);
    unsigned int *virtual_sendbuff = mmap(NULL, buffsize, PROT_READ | PROT_WRITE, MAP_SHARED, dh, SEND_ADDR);
    unsigned int *virtual_recvbuff = mmap(NULL, buffsize, PROT_READ | PROT_WRITE, MAP_SHARED, dh, RECV_ADDR);
    unsigned int *virtual_fifo = mmap(NULL, (fifosize + 1) * buffsize, PROT_READ | PROT_WRITE, MAP_SHARED, dh, FIFO_ADDR);
    if (virtual_address == MAP_FAILED) {
        fprintf(stderr, "[-] AXI DMA registers mmap failed\n");
    }
    if (virtual_sendbuff == MAP_FAILED) {
        fprintf(stderr, "[-] Send buffer mmap failed\n");
    }
    if (virtual_sendbuff == MAP_FAILED) {
        fprintf(stderr, "[-] Send buffer mmap failed\n");
    }
    if (virtual_recvbuff == MAP_FAILED) {
        fprintf(stderr, "[-] Receiver buffer mmap failed\n");
    }
    if (virtual_fifo == MAP_FAILED) {
        fprintf(stderr, "[-] Fifo mmap failed\n");
    }
    memset(virtual_address, 0, buffsize);
    memset(virtual_sendbuff, 0, buffsize);
    memset(virtual_recvbuff, 0, buffsize);
    memset(virtual_fifo, 0, buffsize);
    int head = 0, tail = 0;

    pthread_t sendth, recvth;
    pthread_mutex_t lock;
    pthread_mutex_init(&lock, NULL);

    arguments send_args;
    send_args.virtual_address = virtual_address;
    send_args.virtual_buffer = virtual_sendbuff;
    send_args.head = &head;
    send_args.tail = &tail;
    send_args.buffsize = buffsize;
    send_args.fifosize = fifosize;
    send_args.sockfd = sockfd;
    send_args.lock = &lock;
    send_args.verbose = verbose;

    arguments recv_args;
    recv_args.virtual_address = virtual_address;
    recv_args.virtual_buffer = virtual_recvbuff;
    recv_args.head = &head;
    recv_args.tail = &tail;
    recv_args.buffsize = buffsize;
    recv_args.fifosize = fifosize;
    recv_args.sockfd = sockfd;
    recv_args.lock = &lock;
    recv_args.verbose = verbose;

    start_time = clock();

    if (pthread_create(&sendth, NULL, sender, &send_args)) {
        fprintf(stderr, "[-] Error creating sender thread\n");
        exit(0);
    }
    if (pthread_create(&recvth, NULL, receiver, &recv_args)) {
        fprintf(stderr, "[-] Error creating receiver thread\n");
        exit(0);
    }

    if (pthread_join(sendth, NULL)) {
        fprintf(stderr, "[-] Error joining sender thread\n");
        exit(0);
    }
    if (pthread_join(recvth, NULL)) {
        fprintf(stderr, "[-] Error joining receiver thread\n");
        exit(0);
    }

    pthread_mutex_destroy(&lock);
        close(sockfd);

    fprintf(stderr, "[+] Exit\n");

    return 0;

}

最佳答案

尝试用延迟替换打印语句。

当您进行网络连接时，您的速度会受到网络连接的限制。如果您不考虑这一点，您的传输缓冲区可能会溢出。打印语句会增加一定的延迟，这可能会阻止这种情况发生。用实际延迟替换它们可以检查这一点。

更好的解决方案 - 如果这确实是问题 - 那么就是在写入之前检查缓冲区可用性。

关于仅当存在打印时代码才能正确执行 (C)，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/57919695/

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仅当存在打印时代码才能正确执行 (C)