Exclude non-hybrid CPUs from intel-lpmd via cpu_hybrid check

profiles/pci/power_management/profiles.toml

@@ -5,6 +5,7 @@ vendor_ids = "8086"
 device_ids = "*"
 cpu_family = "6"
 cpu_models = "151 154 183 186 191 170 172 189 204 213"
+cpu_hybrid = true
 priority = 5
 packages = 'intel-lpmd'
 post_install = """

src/data.rs

@@ -370,6 +370,12 @@ pub fn get_all_devices_of_profile(devices: &ListOfDevicesT, profile: &Profile) -
         }
     }
 
+    if let Some(cpu_hybrid) = profile.cpu_hybrid
+        && cpu_hybrid != crate::hwd_misc::is_hybrid_cpu()
+    {
+        return vec![];
+    }
+
     if let Some(gc_versions) = &profile.gc_versions {
         if let Some(hwd_gc_versions) = crate::hwd_misc::get_gc_versions() {
             return get_all_devices_from_gc_versions(devices, &hwd_gc_versions, gc_versions);

src/hwd_misc.rs

@@ -50,6 +50,17 @@ fn parse_cpu_info(content: &str) -> Option<CpuInfo> {
     Some(CpuInfo { vendor: vendor?, family: family?, model: model? })
 }
 
+/// Checks whether the CPU is hybrid, i.e. has E-cores.
+///
+/// The kernel registers the Atom (E-core) perf PMU under `/sys/devices/cpu_atom` on hybrid CPUs.
+/// Non-hybrid dies of hybrid SoCs (e.g. Alder Lake-S without E-cores) still expose the PMU, but
+/// without any Atom CPU in its `cpus` list, so the file has to contain a CPU number.
+#[must_use]
+pub(crate) fn is_hybrid_cpu() -> bool {
+    std::fs::read_to_string("/sys/devices/cpu_atom/cpus")
+        .is_ok_and(|s| s.bytes().any(|b| b.is_ascii_digit()))
+}
+
 #[must_use]
 pub fn get_sysfs_busid_from_amdgpu_path(amdgpu_path: &str) -> &str {
     amdgpu_path.split('/')

src/profile.rs

@@ -49,6 +49,7 @@ pub struct Profile {
     pub gc_versions: Option<Vec<String>>,
     pub cpu_family: Option<String>,
     pub cpu_models: Option<Vec<String>>,
+    pub cpu_hybrid: Option<bool>,
     pub chassis_types: Option<Vec<String>>,
     pub environment_types: Option<Vec<String>>,
     pub driver_conflict_group: Option<String>,
@@ -76,6 +77,7 @@ impl Default for Profile {
             gc_versions: None,
             cpu_family: None,
             cpu_models: None,
+            cpu_hybrid: None,
             chassis_types: None,
             environment_types: None,
             driver_conflict_group: None,
@@ -258,6 +260,7 @@ fn parse_profile(node: &toml::Table, profile_name: &str) -> Result<Profile> {
         gc_versions: parse_whitespace_list(node, "gc_versions"),
         cpu_family: node.get("cpu_family").and_then(|x| x.as_str().map(str::to_string)),
         cpu_models: parse_whitespace_list(node, "cpu_models"),
+        cpu_hybrid: node.get("cpu_hybrid").and_then(toml::Value::as_bool),
         chassis_types: parse_whitespace_list(node, "chassis_types"),
         environment_types: parse_whitespace_list(node, "environment_types"),
         driver_conflict_group: node
@@ -469,6 +472,9 @@ fn profile_into_toml(profile: &Profile) -> toml::Table {
     if let Some(cpu_models) = &profile.cpu_models {
         table.insert("cpu_models".to_owned(), cpu_models.join(" ").into());
     }
+    if let Some(cpu_hybrid) = profile.cpu_hybrid {
+        table.insert("cpu_hybrid".to_owned(), cpu_hybrid.into());
+    }
     if let Some(chassis_types) = &profile.chassis_types {
         table.insert("chassis_types".to_owned(), chassis_types.join(" ").into());
     }
@@ -771,6 +777,7 @@ mod tests {
         assert_eq!(parsed_profiles[0].priority, 5);
         assert_eq!(parsed_profiles[0].packages, "intel-lpmd");
         assert_eq!(parsed_profiles[0].cpu_family, Some("6".to_owned()));
+        assert_eq!(parsed_profiles[0].cpu_hybrid, Some(true));
         assert_eq!(
             parsed_profiles[0].cpu_models,
             Some(vec![

tests/profiles/cpu-profile-test.toml

@@ -5,6 +5,7 @@ vendor_ids = "8086"
 device_ids = "*"
 cpu_family = "6"
 cpu_models = "151 154 183 186 191 170 172 189 204 213"
+cpu_hybrid = true
 priority = 5
 packages = 'intel-lpmd'
 post_install = """