🚀 go-pugleaf

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: �����ܰ�, �ϴ�!
: 1 ns ��Ӧ�Ŀ��� 1 G ��Ƶ��ѽ! �ĸ� CPU �ܱ߸ɻ��ˢ������� ns ���ļ�ʱ��ѽ?
: ������Ӳ����ʱ��, ������õ� Matrox ͼ��ɼ����Ͼ���Ӳ����ʱ��. ��Ҳ��
: 100 ns ���ľ���.

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�ҵ���˼�ǣ��ҿ�30����̣�ѭ��suspend<->resume��30*1000*2�Σ�һ������ʱ��t1

�ɴ��ҵó������л�ʱ��Ϊ: t2=t1/60000

���ҵ�����RTAI LINUX������466�����ʱ��t2��900ns ����

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#define LOOPS 1000
#define NR_TASKS 30
static RT_TASK thread[NR_TASKS];

ÿ��task����ں���Ϊ��
static void rt_task(int i) {
        while (1)
                rt_task_suspend(thread+t);
}

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//CPU_FREQΪCPU����Ƶ�����ҵ�C466�����ֵ���Ϊ: 466,000,000
        hard_cli();
        t = rdtsc();
        for (i = 0; i < LOOPS; i++) {
                for (k = 0; k < NR_TASKS; k++) {
                        rt_task_resume(thread + k);
                }
        }
        t = rdtsc() - t;
        hard_sti();
        printk("\n\nFOR %d TASKS: ", NR_TASKS);
        printk("TIME %d (ms), SUSP/RES SWITCHES %d, ", \
                (int)llimd(t, 1000, CPU_FREQ), 2*NR_TASKS*LOOPS);
        printk("SWITCH TIME (INCLUDING FULL FP SUPPORT) %d (ns)\n", \
                (int)llimd(llimd(t, 1000000000, CPU_FREQ),1,2*30*LOOPS));

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