>From Dave L. (http://lists.linaro.org/pipermail/linaro- dev/2011-September/007560.html) :
I have been unable to reproduce the boot hang problem after unreverting the interrupt patch. Can those experiencing it please verify they are using the latest released lmc tools to create their SD card? And can you please send me your config file and Pandaboard revision? It has been suggested that the limited sample count in the given example is consistent with the fact the ARM oprofile code uses HZ as the sampling frequency (even though it uses a separate timer). I'm not yet familiar with the x86 code for setting the profiling interval on the fly but Frederic Turgis's suggesting of doing the same thing on ARM makes a whole lot of sense. We should make this a new requirement. Once the interrupt issue is resolved I might suggest sampling cpu-cycles as a workaround to real-time sampling granularity, except that there apparently is an issue with reliably getting interrupts from the PMU. Does anyone know if this is still a problem in the A9 (I've only seen it discussed regarding the A8)? If it's still an issue I think it simply kills using PMU event counters with oprofile. We need to do a little work to make configuring hardware events counters into the kernel easier. A recent change means that you need to set at least a couple independent config options for this. This should be simple to fix. -- You received this bug notification because you are a member of Linaro Release Team, which is subscribed to the bug report. https://bugs.launchpad.net/bugs/843628 Title: perf failure on panda (omap4) Status in Linaro Ubuntu Evaluation Builds: Confirmed Status in “linux-linaro-omap” package in Ubuntu: Confirmed Bug description: Though perf lists the PMU events but fails to gather performance counter statistics on panda # perf list List of pre-defined events (to be used in -e): cpu-cycles OR cycles [Hardware event] instructions [Hardware event] cache-references [Hardware event] cache-misses [Hardware event] branch-instructions OR branches [Hardware event] branch-misses [Hardware event] bus-cycles [Hardware event] cpu-clock [Software event] task-clock [Software event] page-faults OR faults [Software event] [...] # perf stat sleep 1 Error: cache-misses event is not supported. Fatal: Not all events could be opened. To manage notifications about this bug go to: https://bugs.launchpad.net/linaro-ubuntu/+bug/843628/+subscriptions _______________________________________________ Mailing list: https://launchpad.net/~linaro-release Post to : linaro-release@lists.launchpad.net Unsubscribe : https://launchpad.net/~linaro-release More help : https://help.launchpad.net/ListHelp
