On Thu, Sep 9, 2021 at 12:09 PM Timo Paulssen [off-list ref] wrote:

Hello perf users and devs,

I'm a contributor to the MoarVM project, which is the interpreter and
jit runtime that powers the Rakudo compiler of the Raku language, which
you may have heard of back when it was still called Perl 6.

We already output a file `/tmp/perf-%d.map` that contains the start and
end addresses of jit-generated symbols, but I don't know how to tell
perf where to look for the binary. Our current code will dump each
compiled piece of code to a folder with an incrementing number. The perf
report frontend will in its current implementation answer the request to
annotate a function by just running objdump against the perf-%d.map
file, which unsurprisingly doesn't work.

I would be glad to hear suggestions, especially ones that don't require
me to generate a full elf file or similar to hold the symbols.

Hi Timo,

Did you look into jitdump? It requires the perf.data file be processed
by perf inject, see the -j option in:
https://man7.org/linux/man-pages/man1/perf-inject.1.html

An example JIT agent is provided for JVMTI:
https://git.kernel.org/pub/scm/linux/kernel/git/acme/linux.git/tree/tools/perf/jvmti?h=perf/core

Thanks,
Ian

Thanks in advance
   - Timo