Fiasco.OC thread execution time

Georg Guba georg.guba at ...256...
Mon Feb 22 18:38:51 CET 2016


I'm trying to implement Platform_thread::execution_time() for Fiasco.OC.
However, when using the code below, I'm getting a null pointer error when
trying to read the UTCB's message register:

Possible null pointer READ at 0 IP 704c0d7c

unsigned long long Platform_thread::execution_time() const
{
unsigned long long time = 0;

if (_utcb)
{
l4_thread_stats_time(_thread.local.dst());
time = *(l4_kernel_clock_t*)l4_utcb_mr()->mr[0];
}

return time;
}

The doc for l4_thread_stats_time(...) says

/**
* \brief Get consumed timed of thread in ┬Ás.
* \ingroup l4_thread_api
* \param thread Thread to get the consumed time from.
*
* The consumed time is returned as l4_kernel_clock_t at UTCB message
* register 0.
*/
L4_INLINE l4_msgtag_t
l4_thread_stats_time(l4_cap_idx_t thread) L4_NOTHROW;

So my usage should be about right.
What am I missing?
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.genode.org/pipermail/users/attachments/20160222/e4514303/attachment.html>


More information about the users mailing list