On Fri, 24 Mar 2017 15:44:43 -0600 Mathieu Poirier mathieu.poirier@linaro.org wrote:
On 24 March 2017 at 15:37, Kim Phillips kim.phillips@arm.com wrote:
On Fri, 24 Mar 2017 13:21:41 -0600 Mathieu Poirier mathieu.poirier@linaro.org wrote:
On 24 March 2017 at 13:04, Kim Phillips kim.phillips@arm.com wrote:
and searching for etr in the current documentation, I assume you mean I should execute perf like this?:
root@juno:~# taskset -c 2 /home/kim/git/OpenCSD/tools/perf/perf record -o perf-etm.data -e cs_etm/@20070000.etr/u --per-thread taskset -c 2 ./sort-O3 failed to mmap with 12 (Cannot allocate memory) root@juno:~#
<snip>
This is using Linus' ToT kernel - the one that doesn't lock up:
There lies the problem - in mainline the ETR driver doesn't have support for the perf API. Coincidentally Mike is working on this.
OK. Returning -ENOTSUPP with wording to such effect on dmesg would be more helpful than 'failed to mmap' (although it's admittedly better than a stack trace).
The perf-opencsd-4.11-rc1 has an ancient (and inefficient) ETR driver that does support the perf API.
Odd, because I was told to use ETR for its superior efficiency.
perf-opencsd-4.11-rc1 locks up my machine though:
[ perf record: Woken up 9 times to write data ] Warning: AUX data lost 8 times out of 9!
[ perf record: Captured and wrote
<hard lockup>
Mathieu
Kim