Re: Cross platform perf reporting

[Milian Wolff <milian.wolff@kdab.com>]

[-- Attachment #1: Type: text/plain, Size: 1696 bytes --]

On Friday, August 12, 2016 2:22:29 PM CEST Milian Wolff wrote:
> Hey all,
> 
> I'm trying to analyze perf.data files that I recorded on one machine
> (usually arm or arm64) on my development machine (x86_64). I have compiled
> a new version of perf (and the corresponding dependencies, where needed) to
> do this.
> 
> Now I do:
> 
> ~~~~~~~~~~~~~~~~~~~~~~~~
> aarch64$ perf record -g ...
> aarch64$ perf archive
> 
> x86_64$ scp aarch64:perf.data* .
> x86_64$ tar xvf perf.data.tar.bz2 -C ~/.debug
> x86_64$ perf report |& less
> -> lots of errors, none of which are displayed in the TUI, such as:
> 
> unwind: target platform=arm64 is not supported
> (often repeated)
> Failed to open /lib/ld-2.21.so, continuing without symbols
> Failed to open /lib/libc-2.21.so, continuing without symbols
> Failed to open /lib/libpthread-2.21.so, continuing without symbols
> Failed to open /lib/libdl-2.21.so, continuing without symbols
> ...
> ~~~~~~~~~~~~~~~~~~~~~~~~

What I notice, is that `perf buildid-list` does not contain any of these 
files. I also don't have the corresponding files in my target's ~/.debug 
folder, where everything seems to work as expected. Is that, because there the 
symbols are read directly from the file and nothing is cached in ~/.debug?

Can I set an environment variable to let perf know to look in secondary paths 
for the libraries? I.e. I hope to make it look into the cross compile sysroot 
for these libraries, instead of literally interpreting the path as a valid 
path on my development machine.

Thanks

-- 
Milian Wolff | milian.wolff@kdab.com | Software Engineer
KDAB (Deutschland) GmbH&Co KG, a KDAB Group company
Tel: +49-30-521325470
KDAB - The Qt Experts

[-- Attachment #2: smime.p7s --]
[-- Type: application/pkcs7-signature, Size: 5903 bytes --]