Re: [ECOS] measure the execution time of each thread

[Gary Thomas <gary@mlbassoc.com>]

On 04/24/2011 04:22 PM, moktar_bouain wrote:
>
>> You don't want to modify that code, just look at how it computes time
>> at a nanosecond scale.
>> Look at the function show_time_in_us() which uses time values
>> based on the function HAL_CLOCK_READ() that reads the system timer
>> (whatever that may be) and calculates time to the most accurate
>> value available in the system.  This is based on the raw clock
>> (often the hardware system clock) that's used to run the system
>> 'tick' timer.  On most systems, this value is accurate to micro-seconds,
>> sometimes even nano-seconds.
>
> Hi Gary,
> I found the function gettimeofday() which returns the time  in  us.
> I create a simple application with eCos containing 1 thread,i like to
> measure the
> execution time(us) of the thread.
>
> void taska(cyg_addrword_t data)
> {
> struct timeval tv1,tv2;
> long long diff;
>
> while(1)
> {
> gettimeofday (&tv1, NULL);
>
> cyg_mutex_lock(&cliblock);
> printf("TASKA \n");
> cyg_mutex_unlock(&cliblock);
>
> cyg_thread_delay(2);
>
> gettimeofday (&tv2, NULL);
> diff=(tv2.tv_sec-tv1.tv_sec) * 1000000 + (tv2.tv_usec-tv1.tv_usec);
>
> printf("Time tv1 is %d\n",tv1.tv_usec);
> printf("Time tv2 is %d\n",tv2.tv_usec);
> printf("The diff is =%d usec\n",diff);
> };
> }
>
> when i run this application in Tsim(simulator of Leon3):
> Time tv1 is 286326803
> Time tv2 is 286326801
> The diff is -1 usec
> Can you tell me what the fault in my program?

Looks like HAL_CLOCK_READ() isn't working on your hardware.
What's your target hardware?  Is it part of the public eCos tree?

-- 
------------------------------------------------------------
Gary Thomas                 |  Consulting for the
MLB Associates              |    Embedded world
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