On Friday 27 August 2010 06:02 pm, Andriy Gapon wrote: > on 28/08/2010 00:43 Jung-uk Kim said the following: > >> Things like that probably do not happen with real hardware much, > >> but they could. > > > > AFAIK, it never happened on a real hardware. > > > >> The only way to deal with this is by following the correct > >> procedure instead of making assumptions based on BSP. But that > >> may be hard. > > > > Feel free to rewrite the patch. I never intended to commit the > > patch, any way. If I ever did, it was a year ago. :-) > > > :-) > > BTW, it may be not that hard. > It seems that 0x4 topology building involves knowing the masks and > we already have that data (just interpreted differently), and APIC > IDs of the CPUs and it seems that we also have that. We don't need > to bind to CPUs to learn their IDs, we can just iterate over > cpu_apic_ids[]. > > The only problem is that currently topo_probe() is called before > assign_cpu_ids() which populates cpu_apic_ids. > assign_cpu_ids depends on topo_probe to know hyperthreading_cpus > value. So, either cpu_apic_ids could be split out or alternatively > we could use cpu_info[] similarly to how it's done in > topo_probe_0xb (skipping !cpu_present and cpu_disabled entries).
If you are really up to this, it has to be a two-pass process. Even then, the dmesg won't be pretty because the topology can only be "announced" after all APs have been started. I mean, nobody's going to like to see a message like this from dmesg output: ... ACPI APIC Table: <FOOBAR> FreeBSD/SMP: Multiprocessor System Detected: 2 CPUs cpu0 (BSP): APIC ID: 0 cpu1 (AP): APIC ID: 1 --- >8 --- Snip several hundred lines! --- >8 --- SMP: AP CPU #1 Launched! FreeBSD/SMP: 1 package(s) x 2 core(s) Root mount waiting for: usbus5 usbus2 Root mount waiting for: usbus5 usbus2 ... In fact, I implemented something like that while I was writing the patch but I discarded it for an obvious reason. ;-) Also, don't forget jhb's work based on ACPI affinity tables. Jung-uk Kim _______________________________________________ freebsd-stable@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to "freebsd-stable-unsubscr...@freebsd.org"
