1 files changed, 78 insertions, 0 deletions
diff --git a/src/bits64/perfcnt/mod.rs b/src/bits64/perfcnt/mod.rs
new file mode 100644
index 0000000..74b80a2
--- /dev/null
+++ b/src/bits64/perfcnt/mod.rs
@@ -0,0 +1,78 @@
+//! Information about available performance counters.
+
+use super::cpuid;
+use phf;
+
+use core::fmt::{Write, Result, Error};
+use core::str;
+
+pub mod intel;
+
+const MODEL_LEN: usize = 30;
+
+#[derive(Default)]
+struct ModelWriter {
+    buffer: [u8; MODEL_LEN],
+    index: usize,
+}
+
+impl ModelWriter {
+    fn as_str(&self) -> &str {
+        str::from_utf8(&self.buffer[..self.index]).unwrap()
+    }
+}
+
+impl Write for ModelWriter {
+    fn write_str(&mut self, s: &str) -> Result {
+        // TODO: There exists probably a more efficient way of doing this:
+        for c in s.chars() {
+            if self.index >= self.buffer.len() {
+                return Err(Error);
+            }
+            self.buffer[self.index] = c as u8;
+            self.index += 1;
+        }
+        Ok(())
+    }
+}
+
+// Format must be a string literal
+macro_rules! get_counters {
+    ($format:expr) => ({
+        let cpuid = cpuid::CpuId::new();
+
+        cpuid.get_vendor_info().map_or(None, |vf| {
+            cpuid.get_feature_info().map_or(None, |fi| {
+                let vendor = vf.as_string();
+                let (family, extended_model, model) = (fi.family_id(), fi.extended_model_id(), fi.model_id());
+
+                let mut writer: ModelWriter = Default::default();
+                // Should work as long as it fits in MODEL_LEN bytes:
+                write!(writer, $format, vendor, family, extended_model, model).unwrap();
+                let key = writer.as_str();
+
+                intel::counters::COUNTER_MAP.get(key)
+            })
+        })
+    });
+}
+
+/// Return all core performance counters for the running micro-architecture.
+pub fn core_counters() -> Option<&'static phf::Map<&'static str, intel::description::IntelPerformanceCounterDescription>> {
+    get_counters!("{}-{}-{:X}{:X}-core")
+}
+
+/// Return all uncore performance counters for the running micro-architecture.
+pub fn uncore_counters() -> Option<&'static phf::Map<&'static str, intel::description::IntelPerformanceCounterDescription>> {
+    get_counters!("{}-{}-{:X}{:X}-uncore")
+}
+
+#[test]
+fn counter_test() {
+    // Note: This will silently fail in case the counter is not available.
+    core_counters().map(|cc| {
+        cc.get("INST_RETIRED.ANY").map(|p| {
+            assert!(p.event_name == "INST_RETIRED.ANY");
+        });
+    });
+}