Correct various issues in scan, and set core affinity properly.

cache_slice/Cargo.toml

@@ -5,4 +5,4 @@ edition = "2021"
 
 [dependencies]
 raw-cpuid = "11.0.2"
-nix = "0.29.0"
+nix = { version = "0.29.0", features = ["sched"] }

cache_slice/src/bin/rdmsr.rs

@@ -1,20 +1,21 @@
 use cache_slice::msr;
 use std::env;
+
 fn main() {
     let mut args = env::args().into_iter();
     args.next();
     for arg in args {
-        match arg.parse::<u32>() {
+        match arg.parse::<u64>() {
             Ok(msr) => {
                 match msr::read_msr_on_cpu(msr, 0) {
                     Ok(result) => {
                         println!("MSR {}: {:x}", msr, result);
-                    },
+                    }
                     Err(e) => {
                         eprintln!("Error, failed to read MSR {}: {}", msr, e);
                     }
                 }
-            },
+            }
             Err(e) => {
                 eprintln!("Error: {}", e);
                 eprintln!("{} is not a valid MSR number", arg);

cache_slice/src/bin/scan.rs

@@ -1,6 +1,7 @@
 use cache_slice::monitor_address;
 use cache_slice::utils::core_per_package;
-use nix::sched::{sched_getaffinity, CpuSet};
+use nix::sched::{sched_getaffinity, sched_setaffinity, CpuSet};
+use nix::unistd::Pid;
 
 
 pub fn main() {
@@ -8,10 +9,23 @@ pub fn main() {
     println!("Found {} cores", nb_cores);
 
     let target = vec![0x0123456789abcdefu64, 64];
-    for core in 0..CpuSet::count() {
+
+    let old = sched_getaffinity(Pid::from_raw(0)).unwrap();
+    let mut core_set = Vec::new();
+    for i in 0..CpuSet::count() {
+        if old.is_set(i).unwrap() {
+            core_set.push(i);
+        }
+    }
+
+
+    for core in core_set {
+        let mut cpu_set = CpuSet::new();
+        cpu_set.set(core).unwrap();
+        sched_setaffinity(Pid::this(), &cpu_set).unwrap();
         for addr in target.iter() {
-            let res = unsafe { monitor_address(addr as *const u64 as *const u8, core as u8, nb_cores) };
-            let slice = res.iter().enumerate().max_by_key(|(i, val)| { val });
+            let res = unsafe { monitor_address(addr as *const u64 as *const u8, core as u8, nb_cores) }.unwrap();
+            let slice = res.iter().enumerate().max_by_key(|(_i, val)| { **val });
             match slice {
                 Some((slice, _)) => {
                     println!("({:2}) Slice for addr {:x}: {}", core, addr as *const u64 as usize, slice)
@@ -22,8 +36,8 @@ pub fn main() {
             }
         }
         for addr in target.iter() {
-            let res = unsafe { monitor_address(addr as *const u64 as *const u8, 0, nb_cores) };
-            let slice = res.iter().enumerate().max_by_key(|(i, val)| { val });
+            let res = unsafe { monitor_address(addr as *const u64 as *const u8, 0, nb_cores) }.unwrap();
+            let slice = res.iter().enumerate().max_by_key(|(_i, val)| { **val });
             match slice {
                 Some((slice, _)) => {
                     println!("({:2}) Slice for addr {:x}: {}", 0, addr as *const u64 as usize, slice)
@@ -33,5 +47,6 @@ pub fn main() {
                 }
             }
         }
+        sched_setaffinity(Pid::this(), &old).unwrap();
     }
 }

cache_slice/src/lib.rs

@@ -2,7 +2,7 @@
 
 use std::arch::x86_64::_mm_clflush;
 use crate::arch::CpuClass::{IntelCore, IntelXeon, IntelXeonSP};
-use crate::arch::get_performance_counters_xeon;
+use crate::arch::{get_performance_counters_core, get_performance_counters_xeon};
 use crate::Error::UnsupportedCPU;
 use crate::msr::{read_msr_on_cpu, write_msr_on_cpu};
 
@@ -10,6 +10,7 @@ pub mod msr;
 pub mod utils;
 mod arch;
 
+#[derive(Debug)]
 pub enum Error {
     UnsupportedCPU,
     InvalidParameter,
@@ -30,7 +31,7 @@ unsafe fn poke(addr: *const u8) {
     }
 }
 
-unsafe fn monitor_xeon(addr: *const u8, cpu: u8, max_cbox: usize) -> Result<Vec<u32>, Error> {
+unsafe fn monitor_xeon(addr: *const u8, cpu: u8, max_cbox: usize) -> Result<Vec<u64>, Error> {
     let performance_counters = if let Some(p) = get_performance_counters_xeon() {
         p
     } else {
@@ -75,24 +76,38 @@ unsafe fn monitor_xeon(addr: *const u8, cpu: u8, max_cbox: usize) -> Result<Vec<
     }
 
     // Read counters
-    let mut result = Vec::new();
+    let mut results = Vec::new();
     for i in 0..max_cbox {
         let result = read_msr_on_cpu(performance_counters.msr_pmon_ctr0[i], cpu)?;
-        result.push(result)
+        results.push(result)
     }
 
-    Ok(result)
+    Ok(results)
 }
 
-fn monitor_core(addr: *const u8, cpu: u8, max_core: u8) -> Result<Vec<u32>, Error> {
+fn monitor_core(addr: *const u8, cpu: u8, max_cbox: usize) -> Result<Vec<u64>, Error> {
     // Note, we need to add the workaround for one missing perf counter here.
+    let performance_counters = if let Some(p) = get_performance_counters_core() {
+        p
+    } else {
+        return Err(UnsupportedCPU);
+    };
+
+    let workaround = if (performance_counters.max_slice as usize) + 1 == max_cbox {
+        true
+    } else if (performance_counters.max_slice as usize) >= max_cbox {
+        false
+    } else {
+        return Err(Error::InvalidParameter);
+    };
+
     unimplemented!()
 }
 
-pub unsafe fn monitor_address(addr: *const u8, cpu: u8, max_cbox: u16) -> Result<Vec<u32>, Error> {
+pub unsafe fn monitor_address(addr: *const u8, cpu: u8, max_cbox: u16) -> Result<Vec<u64>, Error> {
     match arch::determine_cpu_class() {
         Some(IntelCore) => {
-            unimplemented!()
+            unsafe { monitor_core(addr, cpu, max_cbox as usize) }
         }
         Some(IntelXeon) => {
             unsafe { monitor_xeon(addr, cpu, max_cbox as usize) }