Experiences with cvs runtime

[Martin Hunt]

On Wed, 2005-04-27 at 17:44 -0400, Ananth N Mavinakayanahalli wrote:

> Kprobe infrastructure ensures that (un)registration and all handlers run 
> with preemption disabled. 
I believe they have local IRQs disabled, which is not quite the same
thing. From the kernel documentation:

It is possible to prevent a preemption event using local_irq_disable and
local_irq_save.  Note, when doing so, you must be very careful to not
cause an event that would set need_resched and result in a preemption
check.  When in doubt, rely on locking or explicit preemption disabling.


> The problem here is seen during pre and post 
> processing by the runtime. 

Ahh.  That is indeed a problem.  The example probes don't have those
sections protected. I'll fix for the examples in CVS.

> > > - the stp script assumes that relayfs is built in as a kernel module,
> > > while it can be configured tristate (<*>, <M>, <>).

Please try the attached stp script.

Martin

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