On Mon, 2009-06-29 at 17:11 +0200, Jan Kiszka wrote: > Hi Philippe, > > I saw this for 2.6.30, but it obviously also made it into 2.6.29: > > http://git.denx.de/?p=ipipe-2.6.git;a=commitdiff;h=d302f7638b9b52ea90e3c042edd940449cedb7a1 > > What precise problem does it try to solve? Is it a 2.6.30-only problem? > The point is that, last time I checked, the dynamic ftrace approach was > by far not I-pipe compatible. So I suspect we rather need a fix for the > core issue, but keep DYNAMIC_FTRACE off.
There are compatible for basic usage at least, but the way the tracer forced activation of the ftrace layer in 2.6.29+ was wrong in the first place, and this basically wrecked the ppc64 boot sequence. But now that it is right (at least non-x86s are happy with this now), we need DYNAMIC_FTRACE to enable the tracepoints; otherwise we would only get a few xenomai symbols in the trace log (seen on x86*/ppc*). As it is, we do get meaningful traces via /proc/ipipe/trace, but I would not assume that we could not break the kernel when fiddling with ftrace's debugfs interface. Quite frankly, moving the tracer over ftrace brought quite a lot of issues to the non-x86 ports unfortunately (including significant overhead issues on ppc64); the fact that ftrace is a moving target did not help either. This integration probably requires more work. > > Jan > -- Philippe. _______________________________________________ Adeos-main mailing list [email protected] https://mail.gna.org/listinfo/adeos-main
