From mboxrd@z Thu Jan  1 00:00:00 1970
From: Giovanni Gherdovich <ggherdovich@suse.cz>
Subject: profiling Firefox, no perf-<PID>.map file
Date: Sat, 03 Sep 2016 20:53:26 +0200
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Hello,

when profiling firefox with perf (i.e. `perf top` or `perf record`) I
get errors like "Failed to open /tmp/perf-<PID>.map, continuing
without symbols". The perf docs says it has to do with the support for
JIT'ed code (tools/perf/Documentation/jit-interface.txt), which I
guess is produced by firefox' javascript engine (I could be wrong).

The documentation is a bit vague on how to have those perf-<PID>.map
files produced correctly, and the original commit introducing this
feature, 80d496be89ed "perf report: Add support for profiling JIT
generated code" only says "A JIT compiler is required [...]".

Is there a way to profile firefox and get those *.map files?
It's more of a curiosity, I am new to perf and I'm playing around.

Thanks,
Giovanni