Re: Setting physical CPU for a task
Lluís Vilanova <[email protected]>
| Newsgroups | gmane.comp.micro-kernel.l4.devel |
|---|---|
| Message-ID | <[email protected]> |
Adam Lackorzynski writes: > On Mon Aug 05, 2013 at 21:50:55 +0300, Lluís Vilanova wrote: >> I've been unable to see if moe's config files allow to start tasks pinned to a >> specific CPU, and after running the "thread_migrate" example, looks like only >> one CPU (CPU00) is always used: >> >> $ make -C obj/l4/amd64/ qemu E=thread_migrate QEMU_OPTIONS="-serial stdio -vnc ::59000 -smp 2" >> [...] >> Not using serial hack in slow timer handler. >> CPU[0]: AuthenticAMD (6:2:3:0)[00000623] Model: QEMU Virtual CPU version 1.5.1 at 3092MHz >> >> 255/512 Entry I TLB (4K pages) 255 Entry I TLB (4M pages) >> 255/512 Entry D TLB (4K pages) 255 Entry D TLB (4M pages) >> 64 KB L1 I Cache (2-way associative, 64 bytes per line) >> 64 KB L1 D Cache (2-way associative, 64 bytes per line) >> 512 KB L2 U Cache (8-way associative, 64 bytes per line) >> >> Freeing init code/data: 20480 bytes (5 pages) >> [...] >> Ned says: Hi World! >> Ned: loading file: 'rom/thread_migrate.cfg' >> migrate | Found 4 CPUs. >> migrate | Created 12 threads. >> migrate | Migrated Thread00 -> CPU00 >> migrate | Migrated Thread01 -> CPU00 >> >> I've modified "src/l4/conf/modules.list" to add the "thread_migrate" test, and >> I'm using l4re-snapshot-2013060718, with multiprocessing (with a maximum of 4) >> enabled on fiasco. >> >> Looks like the benchmark always detects (L4::Scheduler::info) the number of >> maximum CPUs configured in fiasco, but not the number of CPUs provided by QEMU >> (only CPU 0 is online). > That it finds 4 is on purpose because more CPUs could come up. > Does it work giving Qemu '-cpu core2duo'? Yes, looks like making QEMU look like a somewhat more realistic CPU does no choke Fiasco's ability to detect the number of CPUs. Still, L4::Scheduler::info says there's as many CPUs as the maximum number configured into Fiasco (not the number offered by QEMU). I'm just not sure if this should be considered a bug or a feature. >> Am I missing some step to set all CPUs online? Is it possible to have MOE start >> tasks pinned to a specific CPU? > See the (commented out) "scheduler = ... " settings in, e.g., x86-fb.cfg > and give a fourth parameter, which is a CPU mask. You can check in the > kernel debugger on which CPU a thread is (via lp command). Works like a charm, thanks. Lluis -- "And it's much the same thing with knowledge, for whenever you learn something new, the whole world becomes that much richer." -- The Princess of Pure Reason, as told by Norton Juster in The Phantom Tollbooth _______________________________________________ l4-hackers mailing list [email protected] http://os.inf.tu-dresden.de/mailman/listinfo/l4-hackers