[BUG] CPU temperature not accurately shown on Zen 2 (possibly others)

Describe the bug Package temperature on a Zen 2 CPU shows 0°C or 1°C with kernel 5.18. I'm not entirely sure where this is coming from. Coretemps are displayed correctly.

I believe this may be related to the following change to the k10temp driver: torvalds/linux@02a2484cf8d17a2acf3b9b151147bafaa55ad38c

The following patch to btop restores the expected behaviour on my system:

diff --git a/src/linux/btop_collect.cpp b/src/linux/btop_collect.cpp
index 95028eb..e7c10c7 100644
--- a/src/linux/btop_collect.cpp
+++ b/src/linux/btop_collect.cpp
@@ -295,7 +295,7 @@ namespace Cpu {

                        found_sensors[sensor_name] = {fs::path(basepath + "input"), label, temp, high, crit};

-                       if (not got_cpu and (label.starts_with("Package id") or label.starts_with("Tdie"))) {
+                       if (not got_cpu and (label.starts_with("Package id") or label.starts_with("Tctl"))) {
                            got_cpu = true;
                            cpu_sensor = sensor_name;
                        }

This fix is not optimal as on older CPUs Tctl is offset from the real temperature. Ideally, btop needs to check for Tdie and if it's not present then use Tctl.

To Reproduce Run btop on an affected CPU and show CPU package temperature.

Expected behavior Accurate package temperature is displayed.

Screenshots

Info (please complete the following information):

btop++ version: btop version: 1.2.6
Binary: installed from Arch community repo
(If compiled) Compiler and version:
Architecture: [x86_64, aarch64, etc.] x86_64
Platform: Linux
(Linux) Kernel: 5.18.0-zen1-1-zen-custom
Terminal used: alacritty
Font used: irrelevant

Additional context

2022/05/27 (16:33:24) | ===> btop++ v.1.2.6
2022/05/27 (16:33:24) | DEBUG: Starting in DEBUG mode!
2022/05/27 (16:33:24) | INFO: Logger set to DEBUG
2022/05/27 (16:33:24) | DEBUG: Using locale en_GB.UTF-8
2022/05/27 (16:33:24) | INFO: Running on /dev/pts/2
2022/05/27 (16:33:24) | DEBUG: Loading theme file: /usr/share/btop/themes/gruvbox_dark.theme
2022/05/27 (16:33:25) | INFO: Quitting! Runtime: 00:00:01

GDB Backtrace

Not relevant

aristocratos / btop

[BUG] CPU temperature not accurately shown on Zen 2 (possibly others) #342