gettimeofday with interrupts disabled

[James Dickens]

On 5/8/06, Stone, Joshua I <joshua.i.stone@intel.com> wrote:
> On Sunday, May 07, 2006 6:24 PM, Aziz Eker wrote:
> > I want to get some measurements about the time scheduler_tick()
> > function takes. To do that, I am finding time difference between the
> > start and end of the function using 'gettimeofday_us'. However, the
> > scheduler_tick() function is called with interrupts disabled. Does
> > 'gettimeofday' continue to run even when interrupts are disabled? If
> > not, is there anyway to count the RTC in systemtap?
>
> Calling gettimeofday is only a problem for probes in code sections that
> hold a write lock on xtime_lock.  See bug #2525 for more details:
> http://sources.redhat.com/bugzilla/show_bug.cgi?id=2525
>
what if its an smp machine, and and someone else is calling
gettimeofday?  seems like a race to me..

James Dickens
uadmin.blogspot.com

>
> Josh
>