Hello, > > > On Thu, Aug 21, 2008 at 4:40 AM, TakashiYamamoto > <[EMAIL PROTECTED]> wrote: > >> I've been trying to use perfmon2 on long-running programs on the Cell > >> architecture (a Playstation3). > >> > >> The problem is that pfmon never returns counts higher than 2^32. On > >> kernel 2.6.24 it seemed that the counters were just overflowing and the > >> virtual 64-bit counter just not updated. I updated the kernel to 2.6.26 > >> (which was a lot of pain, turns out there is something broken with USB on > >> kernels more recent than 2.6.24) and the problem is changed a bit but > >> still there. Now the counts seem to max out at 4294967295 > >> > >> For example, I get results like this: > >> > >> > taskset 1 pfmon -e ppc_inst_commit_th0,ppc_inst_commit_th1,cycles > >> > long_running_program > >> 4294967295 PPC_INST_COMMIT_TH0 > >> 0 PPC_INST_COMMIT_TH1 > >> 4294967295 CYCLES > >> > >> Is this a known problem? > > > > Yes. > > The virtual 64-bit counter has not been supported on PS3. > > > > We have a problem to support it. > > The kernel can't use the performance monitor interrupt > > like counter-overflow on PS3, because the hypervisor does not support it. > > So we need the polling the counter status to detect the counter-overflow. > > > Ouch, I was not aware of this serious limitation. > > Is there a possibility to use another interrupt which the hypervisor > would support?
No. > I am not sure how you think you can make poilling work? > > Are you talking about poilling inside the kernel? Yes. I'm thinking about checking the counter status in ctx_switch and timer_handler. But, I'm not sure I can get the exact 64-bit counter value. Takashi Yamamoto. ------------------------------------------------------------------------- This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ _______________________________________________ perfmon2-devel mailing list perfmon2-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/perfmon2-devel
