Quick hack to monitor hit count, ECLK ticks and rough CPU usage for each interrupt level

irq_perf.c

// m68k-amigaos-gcc irq_perf.c -o irq_perf -noixemul -O2 -m68020 --omit-frame-pointer

#include <stdio.h>
#include <stdarg.h>

#include <proto/exec.h>
#include <proto/timer.h>
#include <exec/execbase.h>
#include <devices/timer.h>

// %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

#define RawPutChar(___ch) \
    LP1NR(516, RawPutChar , BYTE, ___ch, d0,\
          , EXEC_BASE_NAME)

void raw_put_char(uint32_t c __asm("d0"), struct ExecBase* SysBase __asm("a3"))
{
    RawPutChar(c);
}

void kprintf(const char *format, ...)
{
    va_list args;
    struct ExecBase* SysBase = *((struct ExecBase **) (4L));

    va_start(args, format);

    // 115200 bps 8N1
    __asm volatile("move.w  #(3546895/115200),0xdff032": : : "cc", "memory");

    RawDoFmt((STRPTR) format, (APTR) args,
             (__fpt) raw_put_char, (APTR) SysBase);

    va_end(args);
}

// %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

struct Device* TimerBase;

struct TimerData
{
    uint32_t            hits;
    uint32_t            ticks;
    struct IntVector    vector;
};

void perfVector(    uint32_t d0 __asm("d0"),
                    uint32_t req __asm("d1"),
                    uint32_t custom __asm("a0"),
                    void* data __asm("a1"),
                    uint32_t jmp __asm("a5"),
                    uint32_t exec __asm("a6") )
{
    struct TimerData* perf = (struct TimerData*)data;

    struct EClockVal sample;
    ReadEClock(&sample);

    perf->ticks -= sample.ev_lo;

    struct IntVector* vector = &perf->vector;

    typedef void (*ISR)(uint32_t d0 __asm("d0"), 
                        uint32_t req __asm("d1"), 
                        uint32_t custom __asm("a0"), 
                        void* data __asm("a1"), 
                        uint32_t jmp __asm("a5"), 
                        uint32_t exec __asm("a6"));

    ISR code = vector->iv_Code;
    data = vector->iv_Data;
    code(d0, req, custom, data, jmp, exec);

    ReadEClock(&sample);

    perf->ticks += sample.ev_lo;
    perf->hits++;
}

#define NUM_INT_LEVELS (16)

struct TimerData perfData[NUM_INT_LEVELS] = { 0 };

struct Interrupt* wrappedSetIntVector(ULONG intNumber __asm("d0"), 
                                    struct Interrupt* interrupt __asm("a1"), 
                                    struct ExecBase* SysBase __asm("a6"))
{
    struct IntVector* vector = &perfData[intNumber].vector;
    Disable();

    struct Interrupt* old = (struct Interrupt*)vector->iv_Node;
    if ((vector->iv_Node = &interrupt->is_Node))
    {
        vector->iv_Data = interrupt->is_Data;
        vector->iv_Code = interrupt->is_Code;
    }
    else
    {
        vector->iv_Data = (void*)-1;
        vector->iv_Code = (void*)-1;
    }

    Enable();
    return old;
}


// %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

int main()
{
    struct MsgPort* timerPort = CreateMsgPort();
    struct timerequest* timeReq = CreateIORequest(timerPort, sizeof(struct timerequest));

    if (OpenDevice((STRPTR)TIMERNAME, UNIT_MICROHZ, (struct IORequest*)timeReq, 0))
    {
        printf("failed to open timer.device\n");
        return -1;
    }
    TimerBase = timeReq->tr_node.io_Device;

    static const uint8_t intLevels = NUM_INT_LEVELS;

    const char* vecNames[NUM_INT_LEVELS] =
    {
        "TBE   ",
        "DSKBLK",
        "SOFT  ",
        "PORTS ",
        "COPER ",
        "VERTB ",
        "BLIT  ",
        "AUD0  ",
        "AUD1  ",
        "AUD2  ",
        "AUD3  ",
        "RBF   ",
        "DSKSYN",
        "EXTER ",
        "INTEN ",
        "NMI   "
    };

    // %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

    Disable();
    for(int16_t i = intLevels-1; i >= 0; --i)
    {
        struct IntVector* vector = &SysBase->IntVects[i];

        struct TimerData* perf = &perfData[i];
        perf->vector = *vector;

        vector->iv_Data = perf;
        vector->iv_Code = perfVector;
        vector->iv_Node = 0;
    }

    void* oldFunc = SetFunction((struct Library*)SysBase, -162, (APTR) wrappedSetIntVector);
    Enable();

    // %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

    printf("ctrl-c to exit; output via serial (115kbps 8N1)\n");

    struct EClockVal lastSample;
    ReadEClock(&lastSample);

    while(1)
    {
        timeReq->tr_node.io_Command = TR_ADDREQUEST;
        timeReq->tr_time.tv_sec = 1;
        timeReq->tr_time.tv_micro = 0;
        SendIO((struct IORequest*)timeReq);

        uint32_t signals = Wait( (1L << timerPort->mp_SigBit) | SIGBREAKF_CTRL_C);
        AbortIO((struct IORequest*)timeReq);
        WaitIO((struct IORequest*)timeReq);

        if (signals & SIGBREAKF_CTRL_C)
            break;

        kprintf("\033[2J");
        struct TimerData currPerf[NUM_INT_LEVELS] = { 0 };
        Disable();
        for(int16_t i = intLevels-1; i >= 0; --i)
        {
            currPerf[i] = perfData[i];
            perfData[i].hits = 0;
            perfData[i].ticks = 0;
        }
        Enable();

        struct EClockVal currSample;
        ReadEClock(&currSample);

        uint64_t prev = *((uint64_t*)&lastSample);
        uint64_t curr = *((uint64_t*)&currSample);

        uint64_t delta = curr - prev;

        for(int16_t i = intLevels-1; i >= 0; --i)
        {
            uint32_t ratio = (uint32_t)100 * (uint32_t)currPerf[i].ticks / (uint32_t)delta;
            kprintf(" %s = [%4ld] = %6ld = %3ld%%%\n", vecNames[i], currPerf[i].hits, currPerf[i].ticks, ratio);
        }

        lastSample = currSample;
    }

    // %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

    Disable();
    SetFunction((struct Library*)SysBase, -162, (APTR) oldFunc);

    for(int16_t i = intLevels-1; i >= 0; --i)
    {
        struct IntVector* vector = &SysBase->IntVects[i];
        struct TimerData* perf = &perfData[i];
        *vector = perf->vector;
    }
    Enable();

    // %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%


    CloseDevice((struct IORequest*)timeReq);
    DeleteIORequest(timeReq);
    DeleteMsgPort(timerPort);
    return 0;
}