From 445fe917b2859e031ad40e30e38cdd135537eae8 Mon Sep 17 00:00:00 2001
From: Kim Walisch <kim.walisch@gmail.com>
Date: Sat, 16 Nov 2024 10:12:19 +0100
Subject: [PATCH] Add comment

---
 src/CpuInfo.cpp | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/src/CpuInfo.cpp b/src/CpuInfo.cpp
index a81f85f3..743ff964 100644
--- a/src/CpuInfo.cpp
+++ b/src/CpuInfo.cpp
@@ -639,6 +639,13 @@ void CpuInfo::init()
   std::vector<size_t> cpuIds;
   cpuIds.reserve(3);
 
+  // Based on my tests, for hybrid CPUs the Linux kernel always lists
+  // all performance CPU cores first and all efficiency CPU cores
+  // last, regardless of the actual physical CPU core layout on the
+  // die. I tested this using an Intel Arrow Lake 245K CPU where the
+  // physical CPU core layout (2 P-cores, 8 E-cores, 4 P-cores) on the
+  // die is different from what the Linux kernel reports.
+
   // Check 1st, last & middle CPU core
   cpuIds.push_back(0);
   if (logicalCpuCores_ >= 2)