failed to open perf event file for event_type cpu-cycles: Permission Denied

[Alireza Khadem]

Hi All,

I want to profile Chromium on my Android device:

Model name: Galaxy S10e

Model number: SM-G970U

Android version: 12

My device is not rooted.

I built chromium based on the instructions on this page. The content of my GN build file is this:
target_os = "android"
target_cpu = "arm64"
is_debug = false
blink_symbol_level = 2
symbol_level = 2
dcheck_always_on = false

After installing the apk, I open Chromium by clicking on the Chromium application on the phone screen, and then I run this command:

out/Default/bin/chrome_public_apk profile --profile-process=renderer -vv

It looks like simpleperf has this error (complete log file is attached):

simpleperf E event_selection_set.cpp:632] failed to open perf event file for event_type cpu-cycles: Permission denied

I checked simpleperf individually on a C++ binary file and it works correctly. I think the problem is that simpleperf is called from the bash user but Chrome is opened by another user, so simpleperf does not have access to the Chrome process.

I appreciate any help. Do I need root access for profiling Chromium?

Best,

- Alireza