perf.c 文件参考

浏览源代码.

函数
static int	PerfOpen (struct file *filep)
static int	PerfClose (struct file *filep)
static ssize_t	PerfRead (struct file *filep, char *buffer, size_t buflen)
static ssize_t	PerfConfig (struct file *filep, const char *buffer, size_t buflen)
static int	PerfIoctl (struct file *filep, int cmd, unsigned long arg)
int	DevPerfRegister (void)
	LOS_MODULE_INIT (DevPerfRegister, LOS_INIT_LEVEL_KMOD_EXTENDED)

变量
static const struct file_operations_vfs	g_perfDevOps

函数说明

DevPerfRegister()

int DevPerfRegister

(

void

)

在文件 perf.c 第 148 行定义.

{
    return register_driver(PERF_DRIVER, &g_perfDevOps, PERF_DRIVER_MODE, 0); /* 0666: file mode */
}

LOS_MODULE_INIT()

LOS_MODULE_INIT	(	DevPerfRegister	,
		LOS_INIT_LEVEL_KMOD_EXTENDED
	)

PerfClose()

static int PerfClose ( struct file *  filep )

static

在文件 perf.c 第 54 行定义.

{
    (void)filep;
    return 0;
}

PerfConfig()

static ssize_t PerfConfig ( struct file *  filep, const char *  buffer, size_t  buflen  )

static

在文件 perf.c 第 91 行定义.

{
    (void)filep;
    int ret;
    PerfConfigAttr attr = {0};
    int attrlen = sizeof(PerfConfigAttr);
 
    if (buflen != attrlen) {
        PRINT_ERR("PerfConfigAttr is %d bytes not %d\n", attrlen, buflen);
        return -EINVAL;
    }
 
    ret = LOS_CopyToKernel(&attr, attrlen, buffer, buflen);
    if (ret != 0) {
        return -EINVAL;
    }
 
    ret = LOS_PerfConfig(&attr);
    if (ret != LOS_OK) {
        PRINT_ERR("perf config error %u\n", ret);
        return -EINVAL;
    }
 
    return 0;
}

函数调用图:

PerfIoctl()

static int PerfIoctl ( struct file *  filep, int  cmd, unsigned long  arg  )

static

在文件 perf.c 第 117 行定义.

{
    (void)filep;
    switch (cmd) {
        case PERF_START:
            LOS_PerfStart((UINT32)arg);
            break;
        case PERF_STOP:
            LOS_PerfStop();
            break;
        default:
            PRINT_ERR("Unknown perf ioctl cmd:%d\n", cmd);
            return -EINVAL;
    }
    return 0;
}

函数调用图:

PerfOpen()

static int PerfOpen ( struct file *  filep )

static

在文件 perf.c 第 48 行定义.

{
    (void)filep;
    return 0;
}

PerfRead()

static ssize_t PerfRead ( struct file *  filep, char *  buffer, size_t  buflen  )

static

在文件 perf.c 第 60 行定义.

{
    /* perf record buffer read */
    (void)filep;
    int ret;
    int realLen;
 
    char *records = LOS_MemAlloc(m_aucSysMem0, buflen);
    if (records == NULL) {
        return -ENOMEM;
    }
 
    realLen = LOS_PerfDataRead(records, buflen); /* get sample data */
    if (realLen == 0) {
        PRINT_ERR("Perf read failed, check whether perf is configured to sample mode.\n");
        ret = -EINVAL;
        goto EXIT;
    }
 
    ret = LOS_CopyFromKernel((void *)buffer, buflen, (void *)records, realLen);
    if (ret != 0) {
        ret = -EINVAL;
        goto EXIT;
    }
 
    ret = realLen;
EXIT:
    LOS_MemFree(m_aucSysMem0, records);
    return ret;
}

函数调用图:

变量说明

g_perfDevOps

const struct file_operations_vfs g_perfDevOps

static

初始值:

= {
    PerfOpen,        
    PerfClose,       
    PerfRead,        
    PerfConfig,      
    NULL,            
    PerfIoctl,       
    NULL,            
#ifndef CONFIG_DISABLE_POLL
    NULL,            
#endif
    NULL,            
}

在文件 perf.c 第 134 行定义.