* Steven Rostedt ([EMAIL PROTECTED]) wrote: > > On Mon, 18 Aug 2008, Mathieu Desnoyers wrote: > > > * Steven Rostedt ([EMAIL PROTECTED]) wrote: > > > > > > On Tue, 19 Aug 2008, Benjamin Herrenschmidt wrote: > > > > > > > > > > > > Hmm, this was originally copied from x86, where we did a cmpxchg, but > > > > > that > > > > > is probably not needed since all of this is done in kstop_machine. > > > > > Also, > > > > > only the "get" is needed. If we don't fault there, we wont fault on > > > > > the > > > > > put (unless we have permissions wrong, and that would be a bug). > > > > > > > > Would it ? How do we make sure the kernel text is mapped writeable ? > > > > > > We map it writeable if FTRACE is enabled. > > > > > > > Argh. See text_poke(). It's there exactly for this purpose on x86. > > Ouch, I just did. text_poke is quite heavy. It would be interesting to see > that performed on 20,000 locations at one time. I could play with it, but > I'm a bit nervous. >
It's alread used to modify the LOCK prefixes in alternative.c and did not seem to be too slow for that.. it should therefore be ok. Mathieu > -- Steve -- Mathieu Desnoyers OpenPGP key fingerprint: 8CD5 52C3 8E3C 4140 715F BA06 3F25 A8FE 3BAE 9A68 _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-dev
