I usually use do_gettimeofday(struct timeval *tv) to get the current time
in kernel space.
It returns the time in struct timeval.
so it reports the time in microseconds, but the resolution depends on jiffies.
I think it can be used enoughly to measture the time in miliseconds.
In your code,
> static int start_time; /* Time in milli */
>
> ...
>
> int init_module(void)
> {
> struct timespec tspec;
-> struct timeval tspec
> tspec = timespec_from_ns(gethrtime());
-> do_gettimeofday(&tspec);
> start_time = tspec.tv_sec*1000+tspec.tv_nsec/1000000;
-> start_time = tspec.tv_sec*1000+tspec.tv_usec/1000;
>
> /* starts the thread */
> ...
> }
>
>
> And I use one periodic thread with a period of one second. Here is the code
> of my thread (I just print the time in millisecond):
>
> void thread_code(void *t)
> {
> int i;
> struct timespec tspec;
-> struct timeval tspec
>
> while(1)
> {
> tspec = timespec_from_ns(gethrtime());
-> do_gettimeofday(&tspec);
> i = tspec.tv_sec*1000+tspec.tv_nsec/1000000;
-> i= tspec.tv_sec*1000+tspec.tv_usec/1000;
>
> i = i-start_time;
> rtl_printf("Time= %d ms\n", (int)i);
> pthread_wait_np();
> }
> }
>
----- Original Message -----
From: "Nicolas Hoffmann" <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: Thursday, June 08, 2000 6:11 PM
Subject: [rtl] Timer resolution
> Hi,
>
> I use RTL V2.0 with Linux kernel 2.2.13. I'm trying to get the time in
> milliseconds from the start of my module. But where I expect to have time in
> ms, it seams I have time in seconds !
>
> I just make a little example.
> In init-module, I initialize the time like this:
>
> static int start_time; /* Time in milli */
>
> ...
>
> int init_module(void)
> {
> struct timespec tspec;
>
> tspec = timespec_from_ns(gethrtime());
> start_time = tspec.tv_sec*1000+tspec.tv_nsec/1000000;
>
> /* starts the thread */
> ...
> }
>
>
> And I use one periodic thread with a period of one second. Here is the code
> of my thread (I just print the time in millisecond):
>
> void thread_code(void *t)
> {
> int i;
> struct timespec tspec;
>
> while(1)
> {
> tspec = timespec_from_ns(gethrtime());
> i = tspec.tv_sec*1000+tspec.tv_nsec/1000000;
>
> i = i-start_time;
> rtl_printf("Time= %d ms\n", (int)i);
> pthread_wait_np();
> }
> }
>
> As result, I have every second the time increased by one (sometimes by two)
> instead of increased by 1000 as I expect !
>
> What's wrong ?
>
> Thanks.
>
> Nioclas.
>
>
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>
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