31 lines
972 B
Plaintext
31 lines
972 B
Plaintext
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/*
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* clock_gettime_stub.c
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* gcc -Wall -c clock_gettime_stub.c
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* posix realtime functions; MacOS user space glue
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*/
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/* @comment
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* other possible implementation using intel builtin rdtsc
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* rdtsc-workaround: http://www.mcs.anl.gov/~kazutomo/rdtsc.html
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*
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* we could get the ticks by doing this
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*
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* __asm __volatile("mov %%ebx, %%esi\n\t"
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* "cpuid\n\t"
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* "xchg %%esi, %%ebx\n\t"
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* "rdtsc"
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* : "=a" (a),
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* "=d" (d)
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* );
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* we could even replace our tricky sched_yield call by assembly code to get a better accurency,
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* anyway the following C stub will satisfy 99% of apps using posix clock_gettime call,
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* moreover, the setter version (clock_settime) could be easly written using mach primitives:
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* http://www.opensource.apple.com/source/xnu/xnu-${VERSION}/osfmk/man/ (clock_[set|get]_time)
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*
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* hackers don't be crackers, don't you use a flush toilet?
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*
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*
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* @see draft: ./posix-realtime-stub/posix-realtime-stub.c
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*
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*/
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