tiny lib/libkvm/kvm_proc.c correction

[Alexander Best]

John Baldwin schrieb am 2010-03-08:
> On Saturday 06 March 2010 3:39:17 am Ulrich Spörlein wrote:
> > On Fri, 05.03.2010 at 12:38:40 -0800, Xin LI wrote:
> > > On 2010/03/05 11:59, Alexander Best wrote:
> > > > Xin LI schrieb am 2010-03-05:
> > > > On 2010/03/05 11:26, Alexander Best wrote:
> > > >>>> hi there. does this look right?

> > > > Not to me, the value is not to be used this way and the
> > > > comments
> > > > above the code explained the same thing.

> > > > I think we should use cputick2usec but it's not available to
> > > > userland
> > > > (one have to copy cpu_tick_frequency and friends).

> > > >> damn you're right. i completely overlooked that comment. would
> > > >> it be
> worth
> > > >> making cputick2usec available to userland? is kvm_proc.c the
> > > >> only
> candidate in
> > > >> need of converting cpu ticks to usecs?

> > > I'm not sure how to do that unfortunately, is there a way to
> > > expose a
> > > kernel variable to userland which also works on a crash dump?

> > ticks *is* available to libkvm, not sure what happens on
> > crashdumps,
> > though. The following patchset has not been tested:

i've just had a look at the overall use of bintime2timeval in the src. it's
not used very often. i only found a handful of calls and in fact with the
exception of kvm_proc.c bintime2timeval() always gets used with a proper
struct bintime.

so i guess it's okay to import cputick2usec() exclusively to kvm_proc.c.

cheers.
alex

> https://www.spoerlein.net/gitweb/?p=freebsd.work/.git;a=commitdiff;h=d500a051eb75dd234166bb11485c0a953aefce1d

> I'm fine with this patch so long as you are reading 'ticks' from the
> crash
> dump.