On Thu, 3 May 2007, Stephane Eranian wrote: > > I am a little confused at how you got to using locked_vm? Shouldn't you > > be using do_mlock() to lock the region of memory and letting the kernel > > page fault handler update locked_vm? In the code, you mention a denial > > of service issue. What is that issue? > > > Using mlock() requires root privileges. You do not want to restrict > monitoring tools (using smapling) to root users. Thus you have to do > the update yourself. Furthermore, we cannot afford to take page fault in > the PMU interrupt handler.
mlock is not guaranteeing that the kernel will leave the memory at its current physical location. It only guarantees that the memory will not be swapped out. Page migration can move mlocked memory. _______________________________________________ perfmon mailing list [email protected] http://www.hpl.hp.com/hosted/linux/mail-archives/perfmon/
