wip on metering host fns

crates/host/Cargo.toml

@@ -14,7 +14,6 @@ holochain_serialized_bytes = "=0.0.53"
 serde = "1"
 tracing = "0.1"
 parking_lot = "0.12"
-once_cell = "1"
 rand = "0.8"
 bimap = "0.6"
 bytes = "1"

crates/host/src/env.rs

@@ -2,15 +2,19 @@ use std::num::TryFromIntError;
 
 use crate::guest::read_bytes;
 use crate::prelude::*;
+use wasmer::Global;
 use wasmer::Memory;
 use wasmer::StoreMut;
 use wasmer::TypedFunction;
+use wasmer_middlewares::metering::MeteringPoints;
 
 #[derive(Clone, Default)]
 pub struct Env {
     pub memory: Option<Memory>,
     pub allocate: Option<TypedFunction<i32, i32>>,
     pub deallocate: Option<TypedFunction<(i32, i32), ()>>,
+    pub wasmer_metering_points_exhausted: Option<Global>,
+    pub wasmer_metering_remaining_points: Option<Global>,
 }
 
 impl Env {
@@ -97,4 +101,84 @@ impl Env {
             }
         }
     }
+
+    /// Mimics upstream function of the same name but accesses the global directly from env.
+    /// https://github.com/wasmerio/wasmer/blob/master/lib/middlewares/src/metering.rs#L285
+    pub fn get_remaining_points(
+        &self,
+        store_mut: &mut StoreMut,
+    ) -> Result<MeteringPoints, wasmer::RuntimeError> {
+        let exhausted: i32 = self
+            .wasmer_metering_points_exhausted
+            .as_ref()
+            .ok_or(wasm_error!(WasmErrorInner::Memory))?
+            .get(store_mut)
+            .try_into()
+            .map_err(|_| wasm_error!(WasmErrorInner::PointerMap))?;
+
+        if exhausted > 0 {
+            return Ok(MeteringPoints::Exhausted);
+        }
+
+        let points = self
+            .wasmer_metering_remaining_points
+            .as_ref()
+            .ok_or(wasm_error!(WasmErrorInner::Memory))?
+            .get(store_mut)
+            .try_into()
+            .map_err(|_| wasm_error!(WasmErrorInner::PointerMap))?;
+
+        Ok(MeteringPoints::Remaining(points))
+    }
+
+    pub fn set_remaining_points(
+        &self,
+        store_mut: &mut StoreMut,
+        points: u64,
+    ) -> Result<(), wasmer::RuntimeError> {
+        self.wasmer_metering_remaining_points
+            .as_ref()
+            .ok_or(wasm_error!(WasmErrorInner::Memory))?
+            .set(store_mut, points.into())
+            .map_err(|_| wasm_error!(WasmErrorInner::PointerMap))?;
+
+        self.wasmer_metering_points_exhausted
+            .as_ref()
+            .ok_or(wasm_error!(WasmErrorInner::Memory))?
+            .set(store_mut, 0i32.into())
+            .map_err(|_| wasm_error!(WasmErrorInner::PointerMap))?;
+        Ok(())
+    }
+
+    pub fn decrease_points(
+        &self,
+        store_mut: &mut StoreMut,
+        points: u64,
+    ) -> Result<MeteringPoints, wasmer::RuntimeError> {
+        match self.get_remaining_points(store_mut) {
+            Ok(MeteringPoints::Remaining(remaining)) => {
+                if remaining < points {
+                    self.wasmer_metering_remaining_points
+                        .as_ref()
+                        .ok_or(wasm_error!(WasmErrorInner::Memory))?
+                        .set(store_mut, 0i32.into())
+                        .map_err(|_| wasm_error!(WasmErrorInner::PointerMap))?;
+                    self.wasmer_metering_points_exhausted
+                        .as_ref()
+                        .ok_or(wasm_error!(WasmErrorInner::Memory))?
+                        .set(store_mut, 1i32.into())
+                        .map_err(|_| wasm_error!(WasmErrorInner::PointerMap))?;
+                    Ok(MeteringPoints::Exhausted)
+                } else {
+                    self.wasmer_metering_remaining_points
+                        .as_ref()
+                        .ok_or(wasm_error!(WasmErrorInner::Memory))?
+                        .set(store_mut, (remaining - points).into())
+                        .map_err(|_| wasm_error!(WasmErrorInner::PointerMap))?;
+                    Ok(MeteringPoints::Remaining(remaining - points))
+                }
+            }
+            v => v,
+        }
+    }
 }

crates/host/src/module.rs

@@ -3,9 +3,7 @@ use crate::prelude::*;
 use bimap::BiMap;
 use bytes::Bytes;
 use holochain_wasmer_common::WasmError;
-use once_cell::sync::{Lazy, OnceCell};
 use parking_lot::Mutex;
-use parking_lot::RwLock;
 use std::collections::BTreeMap;
 use std::sync::Arc;
 use wasmer::Cranelift;
@@ -123,8 +121,6 @@ pub struct SerializedModuleCache {
     cranelift: fn() -> Cranelift,
 }
 
-pub static SERIALIZED_MODULE_CACHE: OnceCell<RwLock<SerializedModuleCache>> = OnceCell::new();
-
 impl PlruCache for SerializedModuleCache {
     type Item = SerializedModule;
 
@@ -214,8 +210,6 @@ pub struct InstanceCache {
     key_map: PlruKeyMap,
     cache: BTreeMap<CacheKey, Arc<InstanceWithStore>>,
 }
-pub static INSTANCE_CACHE: Lazy<RwLock<InstanceCache>> =
-    Lazy::new(|| RwLock::new(InstanceCache::default()));
 
 impl PlruCache for InstanceCache {
     type Item = InstanceWithStore;

test/Cargo.toml

@@ -17,6 +17,7 @@ parking_lot = "0.12"
 wasmer = "=4.2.2"
 wasmer-middlewares = "=4.2.2"
 test-fuzz = "=3.0.4"
+once_cell = "1"
 
 [dev-dependencies]
 env_logger = "0.8"

test/benches/bench.rs

@@ -116,7 +116,7 @@ pub fn wasm_call(c: &mut Criterion) {
 pub fn wasm_call_n(c: &mut Criterion) {
     let mut group = c.benchmark_group("wasm_call_n");
 
-    let instance_with_store = TestWasm::Io.instance();
+    let instance_with_store = TestWasm::Io.unmetered_instance();
 
     macro_rules! bench_n {
         ( $fs:expr; $t:ty; ) => {
@@ -165,7 +165,7 @@ pub fn wasm_call_n(c: &mut Criterion) {
 pub fn test_process_string(c: &mut Criterion) {
     let mut group = c.benchmark_group("test_process_string");
 
-    let instance_with_store = TestWasm::Test.instance();
+    let instance_with_store = TestWasm::Test.unmetered_instance();
 
     for n in vec![0, 1, 1_000, 1_000_000] {
         group.throughput(Throughput::Bytes(n));
@@ -203,7 +203,7 @@ pub fn test_instances(c: &mut Criterion) {
             let mut jhs = Vec::new();
             for _ in 0..25 {
                 let input = input.clone();
-                let instance_with_store = TestWasm::Test.instance();
+                let instance_with_store = TestWasm::Test.unmetered_instance();
                 let instance = instance_with_store.instance.clone();
                 let store = instance_with_store.store.clone();
                 let jh = std::thread::spawn(move || {

test/src/import.rs

@@ -1,4 +1,5 @@
 use crate::debug;
+use crate::decrease_points;
 use crate::err;
 use crate::pages;
 use crate::short_circuit;
@@ -34,6 +35,11 @@ pub fn imports(store: &mut StoreMut, function_env: &FunctionEnv<Env>) -> Imports
                 function_env,
                 debug
             ),
+            "__hc__decrease_points_1" => Function::new_typed_with_env(
+                store,
+                function_env,
+                decrease_points
+            ),
             "__hc__guest_err_1" => Function::new_typed_with_env(
                 store,
                 function_env,

test/src/test.rs

@@ -4,6 +4,7 @@ pub mod wasms;
 use holochain_wasmer_host::prelude::*;
 use test_common::SomeStruct;
 use wasmer::FunctionEnvMut;
+use wasmer_middlewares::metering::MeteringPoints;
 
 pub fn short_circuit(
     _env: FunctionEnvMut<Env>,
@@ -49,6 +50,31 @@ pub fn debug(
     Ok(())
 }
 
+pub fn decrease_points(
+    mut function_env: FunctionEnvMut<Env>,
+    guest_ptr: GuestPtr,
+    len: Len,
+) -> Result<u64, wasmer::RuntimeError> {
+    let (env, mut store_mut) = function_env.data_and_store_mut();
+    let points: u64 = env.consume_bytes_from_guest(&mut store_mut, guest_ptr, len)?;
+    let points_before = env.get_remaining_points(&mut store_mut)?;
+    let remaining_points = env.decrease_points(&mut store_mut, points)?;
+    let points_after = env.get_remaining_points(&mut store_mut)?;
+    assert_eq!(points_after, remaining_points);
+    env.move_data_to_guest(
+        &mut store_mut,
+        Ok::<(u64, u64), WasmError>(match (points_before, remaining_points) {
+            (
+                MeteringPoints::Remaining(points_before),
+                MeteringPoints::Remaining(remaining_points),
+            ) => (points_before, remaining_points),
+            // This will error on the guest because it will require at least 1 point
+            // to deserialize this value.
+            _ => (0, 0),
+        }),
+    )
+}
+
 pub fn err(_: FunctionEnvMut<Env>) -> Result<(), wasmer::RuntimeError> {
     Err(wasm_error!(WasmErrorInner::Guest("oh no!".into())).into())
 }
@@ -91,7 +117,8 @@ pub mod tests {
             vec![
                 "__hc__short_circuit_5".to_string(),
                 "__hc__test_process_string_2".to_string(),
-                "__hc__test_process_struct_2".to_string()
+                "__hc__test_process_struct_2".to_string(),
+                "__hc__decrease_points_1".to_string(),
             ],
             module
                 .imports()
@@ -289,7 +316,7 @@ pub mod tests {
             Err(runtime_error) => assert_eq!(
                 WasmError {
                     file: "src/wasm.rs".into(),
-                    line: 100,
+                    line: 101,
                     error: WasmErrorInner::Guest("oh no!".into()),
                 },
                 runtime_error.downcast().unwrap(),
@@ -330,7 +357,7 @@ pub mod tests {
                 assert_eq!(
                     WasmError {
                         file: "src/wasm.rs".into(),
-                        line: 128,
+                        line: 129,
                         error: WasmErrorInner::Guest("it fails!: ()".into()),
                     },
                     runtime_error.downcast().unwrap(),
@@ -339,4 +366,42 @@ pub mod tests {
             Ok(_) => unreachable!(),
         };
     }
+
+    #[test]
+    fn decrease_points_test() {
+        let InstanceWithStore { store, instance } = TestWasm::Test.instance();
+        let dec_by = 1_000_000_u64;
+        let points_before: u64 = instance
+            .exports
+            .get_global("wasmer_metering_remaining_points")
+            .unwrap()
+            .get(&mut store.lock().as_store_mut())
+            .unwrap_i64()
+            .try_into()
+            .unwrap();
+
+        let (before_decrease, after_decrease): (u64, u64) = guest::call(
+            &mut store.lock().as_store_mut(),
+            instance.clone(),
+            "decrease_points",
+            dec_by,
+        )
+        .unwrap();
+
+        let points_after: u64 = instance
+            .exports
+            .get_global("wasmer_metering_remaining_points")
+            .unwrap()
+            .get(&mut store.lock().as_store_mut())
+            .unwrap_i64()
+            .try_into()
+            .unwrap();
+
+        assert!(before_decrease - after_decrease == dec_by);
+        assert!(
+            points_before > before_decrease
+                && before_decrease > after_decrease
+                && after_decrease > points_after
+        );
+    }
 }