On Thu, Apr 02, 2009 at 11:49:55AM +0200, Nils Faerber wrote: > > So I would suggest - if possible - to compile everything with a > > different toolchain and then do a diff or at least compare file sizes of > > some core components. > > This is not that easy. We are talking about recompiling *everything*, > i.e. the whole distribution. Tools like OE have been created because > cross distribution building is not that easy. I tend to go blackbox: We have to focus on only making an application SIGILL fast and reproducible. I mean: a minimal rootfs that probably only has a linuxrc or something like that, that makes an application SIGILL, and halts or reboots. I also think that threads are the problem, but we can't say for sure. Anyway: I guess the threading works until some other process introduces something into the cache. So making it reproducible can be a little hard. As for a solution: the system can reboot fast. I guess we can start with putting some cache flushes around an important schedule point so that it disappears, and then move those flushes to more specific scheduler functions, or even look at what kind of flush should be done. That's not a fun job, but it get's us to a point where we can start pointing at things, and finally makes us understand it. So we are here: 1) We have apps that sigill. Great, we have to detect that, log it and reboot. 2) We have variant that works (cache turned off). Great, we have to detect that, log it and reboot. The next step is to get to step 2 with mere cache flushes. For that we have to know the diffent caches: TLB, icache, dcache, maybe flush by cacheline? If we can get to 2 with cache flushes, we can start pointing at a cache.
Anyway: work says more than theories. Nils: do you have a setup that a new kernel quickly, and a setup that SIGILL's fast? Or should I just focus on the SIGILL fast user-space part? (To speed up testing) -- .signature not found _______________________________________________ Mipsbook-devel mailing list Mipsbook-devel@linuxtogo.org http://lists.linuxtogo.org/cgi-bin/mailman/listinfo/mipsbook-devel
