Qt Quick Ultralite Platform Porting Guide Qt Quick Ultralite Platform Porting Guide

C

Implementing performance metrics platform APIs

Derive from the Qul::Platform::PerformanceMetrics structure and override the virtual functions for maximum heap usage, maximum stack usage, and CPU load. Create a custom implementation for the performance metrics for your platform:

struct ExamplePerformanceMetrics : PerformanceMetrics
{
    uint64_t maxHeapUsage() QUL_DECL_OVERRIDE
    {
        /*Custom maximum heap usage function depending on Platform and toolchains.*/
        return 0;
    }
    uint64_t maxStackUsage() QUL_DECL_OVERRIDE
    {
        /*Custom maximum stack usage function depending on Platform and toolchains.*/
        return 0;
    }
#if defined(QUL_ENABLE_HARDWARE_PERFORMANCE_LOGGING)
    float cpuLoad() QUL_DECL_OVERRIDE
    {
        /*Custom CPU load measurement function depending on Platform and toolchains.*/
        return 0.f;
    };
#endif
};

Implement PlatformContext::performanceMetrics in your platform context to return this information to provide the ExamplePerformanceMetrics structure access to the Qt Quick Ultralite Core.

Platform::PerformanceMetrics *ExamplePlatform::performanceMetrics(void)
{
    static ExamplePerformanceMetrics metrics;
    return &metrics;
}

Memory statistics

The platform offers functions to get memory statistics like heap and stack sizes.

The Qul::Platform::printHeapStats and Qul::Platform::printStackStats functions must be implemented to print such information. You could use the mallinfo() function, if it is available on your platform.

GCC compilerIAR compiler

void printHeapStats(void)
{
    struct mallinfo mi = mallinfo();
    PlatformInterface::log("Heap: %u/%u (in-use/total)\r\n", mi.uordblks, mi.arena);
}

void printStackStats(void)
{
    // Replace this with actual measuring for your platform
    uint32_t maxUsedStackSize = 0;
    PlatformInterface::log("Stack: %u (peak)\r\n", maxUsedStackSize);
}

void printHeapStats(void)
{
    struct mallinfo mi = __iar_dlmallinfo();
    PlatformInterface::log("Heap: %u/%u (in-use/total)\r\n", mi.uordblks, mi.arena);
}

void printStackStats(void)
{
    // Replace this with actual measuring for your platform
    uint32_t maxUsedStackSize = 0;
    PlatformInterface::log("Stack: %u (peak)\r\n", maxUsedStackSize);
}

Qt Quick Ultralite Platform Porting Guide Qt Quick Ultralite Platform Porting Guide

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