Re: SMP question w.r.t. reading kernel variables

2011-04-18 Thread John Baldwin
On Monday, April 18, 2011 4:22:37 pm Rick Macklem wrote: > > On Sunday, April 17, 2011 3:49:48 pm Rick Macklem wrote: > > > Hi, > > > > > > I should know the answer to this, but... When reading a global > > > kernel > > > variable, where its modifications are protected by a mutex, is it > > > neces

Re: SMP question w.r.t. reading kernel variables

2011-04-18 Thread Rick Macklem
> > > All of this makes sense. What I was concerned about was memory cache > consistency and whet (if anything) has to be done to make sure a Oops, "whet" should have been "what".. ___ freebsd-hackers@freebsd.org mailing list http://lists.freebsd.org/mail

Re: SMP question w.r.t. reading kernel variables

2011-04-18 Thread Rick Macklem
> On Sunday, April 17, 2011 3:49:48 pm Rick Macklem wrote: > > Hi, > > > > I should know the answer to this, but... When reading a global > > kernel > > variable, where its modifications are protected by a mutex, is it > > necessary to get the mutex lock to just read its value? > > > > For example:

Re: Add SUM sysctl

2011-04-18 Thread Pawel Jakub Dawidek
On Mon, Apr 18, 2011 at 08:24:57AM -0400, John Baldwin wrote: > On Saturday, April 16, 2011 10:24:44 am rank1see...@gmail.com wrote: > > After compilation of kernel and world in MUM, kernel is installed in MUM, > > but to install world, we reboot into SUM, then install world. (HANDBOOK) > > Now, i

Re: SMP question w.r.t. reading kernel variables

2011-04-18 Thread John Baldwin
On Sunday, April 17, 2011 3:49:48 pm Rick Macklem wrote: > Hi, > > I should know the answer to this, but... When reading a global kernel > variable, where its modifications are protected by a mutex, is it > necessary to get the mutex lock to just read its value? > > For example: > Aif ((mp->m

Re: Add SUM sysctl

2011-04-18 Thread John Baldwin
On Saturday, April 16, 2011 10:24:44 am rank1see...@gmail.com wrote: > After compilation of kernel and world in MUM, kernel is installed in MUM, > but to install world, we reboot into SUM, then install world. (HANDBOOK) > Now, in case of GELI usage AND if upgrading is taking place, i.e; 8.2 -> >

Re: Add SUM sysctl

2011-04-18 Thread Paul Schenkeveld
On Mon, Apr 18, 2011 at 01:52:15PM +0200, rank1see...@gmail.com wrote: > > There are 2 ways of going into SUM (Single user mode) > 1) Rebooting into it > 2) Drop from MUM > > My solution MUST cover both cases, of entering into SUM. > > Once I enter SUM, I set it up, via 1 script, which enables d

Re: Add SUM sysctl

2011-04-18 Thread rank1seeker
I would like, to thank you all, for your ideas. There are 2 ways of going into SUM (Single user mode) 1) Rebooting into it 2) Drop from MUM My solution MUST cover both cases, of entering into SUM. Once I enter SUM, I set it up, via 1 script, which enables deamons and other stuff, that I need, f