Get the number of available CBox on Intel Core using MSR_UNC_CBO_CONFIG

This commit is contained in:
Guillaume DIDIER 2024-07-03 11:04:23 +02:00
parent d3aa4d1317
commit 94af9a99cc
2 changed files with 18 additions and 14 deletions

View File

@ -135,6 +135,7 @@ pub struct XeonPerfCounters {
}
pub struct CorePerfCounters {
pub msr_unc_cbo_config: u64,
pub max_slice: u16,
pub msr_unc_perf_global_ctr: u64,
pub val_enable_ctrs: u64,
@ -221,6 +222,7 @@ const BROADWELL_XEON: XeonPerfCounters = XeonPerfCounters {
// TODO find appropriate values
const ALDER_LAKE_TO_RAPTOR_LAKE_CORE: CorePerfCounters = CorePerfCounters {
msr_unc_cbo_config: 0x396,
max_slice: 10,
msr_unc_perf_global_ctr: 0x2ff0,
val_enable_ctrs: 0x20000000, // To validate
@ -233,6 +235,7 @@ const ALDER_LAKE_TO_RAPTOR_LAKE_CORE: CorePerfCounters = CorePerfCounters {
// TODO verify his on ICELAKE, and appropriate values. Also deal with backport Cypress Cove ?
const CANNON_LAKE_TO_TIGER_LAKE_CORE: CorePerfCounters = CorePerfCounters {
msr_unc_cbo_config: 0x396,
max_slice: 8, // To validate
msr_unc_perf_global_ctr: 0xe01,
val_enable_ctrs: 0x20000000, // To validate
@ -244,6 +247,7 @@ const CANNON_LAKE_TO_TIGER_LAKE_CORE: CorePerfCounters = CorePerfCounters {
};
const SKYLAKE_KABYLAKE_CORE: CorePerfCounters = CorePerfCounters {
msr_unc_cbo_config: 0x396,
max_slice: 7,
msr_unc_perf_global_ctr: 0xe01,
val_enable_ctrs: 0x20000000,
@ -257,7 +261,8 @@ const SKYLAKE_KABYLAKE_CORE: CorePerfCounters = CorePerfCounters {
// This is documented in Intel SDM, 20.3.4.6 (in March 2024 edition)
const SANDYBRIDGE_TO_BROADWELL_CORE: CorePerfCounters = CorePerfCounters {
max_slice: 0,
msr_unc_cbo_config: 0x396,
max_slice: 4,
msr_unc_perf_global_ctr: 0x391,
// Go in MSR_UNC_PERF_GLOBAL_CTR EN (bit 29) set to one, and route PMI to core 1-4 upon overflow.
val_enable_ctrs: 0x2000000f,

View File

@ -3,7 +3,7 @@
use std::arch::x86_64::_mm_clflush;
use crate::arch::CpuClass::{IntelCore, IntelXeon, IntelXeonSP};
use crate::arch::{get_performance_counters_core, get_performance_counters_xeon};
use crate::Error::UnsupportedCPU;
use crate::Error::{InvalidParameter, UnsupportedCPU};
use crate::msr::{read_msr_on_cpu, write_msr_on_cpu};
pub mod msr;
@ -39,7 +39,7 @@ unsafe fn monitor_xeon(addr: *const u8, cpu: u8, max_cbox: usize) -> Result<Vec<
};
if (performance_counters.max_slice as usize) < max_cbox {
return Err(Error::InvalidParameter);
return Err(InvalidParameter);
}
// Freeze counters
@ -89,7 +89,7 @@ unsafe fn monitor_xeon(addr: *const u8, cpu: u8, max_cbox: usize) -> Result<Vec<
Ok(results)
}
fn monitor_core(addr: *const u8, cpu: u8, mut max_cbox: usize) -> Result<Vec<u64>, Error> {
fn monitor_core(addr: *const u8, cpu: u8) -> 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
@ -97,15 +97,13 @@ fn monitor_core(addr: *const u8, cpu: u8, mut max_cbox: usize) -> Result<Vec<u64
return Err(UnsupportedCPU);
};
let workaround = if (performance_counters.max_slice as usize) + 1 == max_cbox {
max_cbox = performance_counters.max_slice as usize;
eprintln!("Using workaround");
true
} else if (performance_counters.max_slice as usize) >= max_cbox {
false
} else {
return Err(Error::InvalidParameter);
};
eprint!("Finding the number of CBox available... ");
let max_cbox = read_msr_on_cpu(performance_counters.msr_unc_cbo_config, cpu)? & 0xF; // TODO magic number (mask for bit 3:0)
eprintln!("{}", max_cbox);
if max_cbox > performance_counters.max_slice as u64 {
return Err(InvalidParameter);
}
eprintln!("Disabling counters");
write_msr_on_cpu(performance_counters.msr_unc_perf_global_ctr, cpu, performance_counters.val_disable_ctrs)?;
@ -150,10 +148,11 @@ fn monitor_core(addr: *const u8, cpu: u8, mut max_cbox: usize) -> Result<Vec<u64
Ok(results)
}
// Note: max_cbox is not used on Intel Core.
pub unsafe fn monitor_address(addr: *const u8, cpu: u8, max_cbox: u16) -> Result<Vec<u64>, Error> {
match arch::determine_cpu_class() {
Some(IntelCore) => {
unsafe { monitor_core(addr, cpu, max_cbox as usize) }
unsafe { monitor_core(addr, cpu) }
}
Some(IntelXeon) => {
unsafe { monitor_xeon(addr, cpu, max_cbox as usize) }