Redo primary context and fix various long-standing bugs.

This should fix Blender 4.2. I'll clean up tomorrow

zluda/src/impl/context.rs

@@ -7,7 +7,7 @@ use cuda_types::*;
 use hip_runtime_sys::*;
 use rustc_hash::{FxHashMap, FxHashSet};
 use std::ptr;
-use std::sync::atomic::{AtomicU32, Ordering};
+use std::sync::atomic::AtomicU32;
 use std::sync::Mutex;
 use std::{cell::RefCell, ffi::c_void};
 
@@ -28,57 +28,104 @@ impl ZludaObject for ContextData {
     const LIVENESS_FAIL: CUresult = CUresult::CUDA_ERROR_INVALID_CONTEXT;
 
     fn drop_with_result(&mut self, _: bool) -> Result<(), CUresult> {
-        let mutable = self
-            .mutable
-            .get_mut()
-            .map_err(|_| CUresult::CUDA_ERROR_UNKNOWN)?;
-        fold_cuda_errors(mutable.streams.iter().copied().map(|s| {
-            unsafe { LiveCheck::drop_box_with_result(s, true)? };
-            Ok(())
-        }))
+        self.with_inner_mut(|mutable| {
+            fold_cuda_errors(
+                mutable
+                    .streams
+                    .iter()
+                    .copied()
+                    .map(|s| unsafe { LiveCheck::drop_box_with_result(s, true) }),
+            )
+        })?
     }
 }
 
 pub(crate) struct ContextData {
-    pub(crate) flags: AtomicU32,
-    is_primary: bool,
-    pub(crate) ref_count: AtomicU32,
     pub(crate) device: hipDevice_t,
-    pub(crate) mutable: Mutex<ContextDataMutable>,
+    pub(crate) variant: ContextVariant,
+}
+
+pub(crate) enum ContextVariant {
+    NonPrimary(NonPrimaryContextData),
+    Primary(Mutex<PrimaryContextData>),
+}
+
+pub(crate) struct PrimaryContextData {
+    pub(crate) ref_count: u32,
+    pub(crate) flags: u32,
+    pub(crate) mutable: ContextInnerMutable,
+}
+
+pub(crate) struct NonPrimaryContextData {
+    flags: AtomicU32,
+    mutable: Mutex<ContextInnerMutable>,
 }
 
 impl ContextData {
-    pub(crate) fn new(
-        flags: u32,
-        device: hipDevice_t,
-        is_primary: bool,
-        initial_refcount: u32,
-    ) -> Result<Self, CUresult> {
-        Ok(ContextData {
-            flags: AtomicU32::new(flags),
+    pub(crate) fn new_non_primary(flags: u32, device: hipDevice_t) -> Self {
+        Self {
             device,
-            ref_count: AtomicU32::new(initial_refcount),
-            is_primary,
-            mutable: Mutex::new(ContextDataMutable::new()),
+            variant: ContextVariant::NonPrimary(NonPrimaryContextData {
+                flags: AtomicU32::new(flags),
+                mutable: Mutex::new(ContextInnerMutable::new()),
+            }),
+        }
+    }
+
+    pub(crate) fn new_primary(device: hipDevice_t) -> Self {
+        Self {
+            device,
+            variant: ContextVariant::Primary(Mutex::new(PrimaryContextData {
+                ref_count: 0,
+                flags: 0,
+                mutable: ContextInnerMutable::new(),
+            })),
+        }
+    }
+
+    pub(crate) fn with_inner_mut<T>(
+        &self,
+        fn_: impl FnOnce(&mut ContextInnerMutable) -> T,
+    ) -> Result<T, CUresult> {
+        Ok(match self.variant {
+            ContextVariant::Primary(ref mutex_over_primary_ctx_data) => {
+                let mut primary_ctx_data = mutex_over_primary_ctx_data
+                    .lock()
+                    .map_err(|_| CUresult::CUDA_ERROR_UNKNOWN)?;
+                fn_(&mut primary_ctx_data.mutable)
+            }
+            ContextVariant::NonPrimary(NonPrimaryContextData { ref mutable, .. }) => {
+                let mut ctx_data_mutable =
+                    mutable.lock().map_err(|_| CUresult::CUDA_ERROR_UNKNOWN)?;
+                fn_(&mut ctx_data_mutable)
+            }
         })
     }
 }
 
-pub(crate) struct ContextDataMutable {
+pub(crate) struct ContextInnerMutable {
     pub(crate) streams: FxHashSet<*mut stream::Stream>,
     pub(crate) modules: FxHashSet<*mut module::Module>,
     // Field below is here to support CUDA Driver Dark API
     pub(crate) local_storage: FxHashMap<*mut c_void, LocalStorageValue>,
 }
 
-impl ContextDataMutable {
-    fn new() -> Self {
-        ContextDataMutable {
+impl ContextInnerMutable {
+    pub(crate) fn new() -> Self {
+        ContextInnerMutable {
             streams: FxHashSet::default(),
             modules: FxHashSet::default(),
             local_storage: FxHashMap::default(),
         }
     }
+    pub(crate) fn drop_with_result(&mut self) -> Result<(), CUresult> {
+        fold_cuda_errors(
+            self.streams
+                .iter()
+                .copied()
+                .map(|s| unsafe { LiveCheck::drop_box_with_result(s, true) }),
+        )
+    }
 }
 
 pub(crate) struct LocalStorageValue {
@@ -94,7 +141,7 @@ pub(crate) unsafe fn create(
     if pctx == ptr::null_mut() {
         return Err(CUresult::CUDA_ERROR_INVALID_VALUE);
     }
-    let context_box = Box::new(LiveCheck::new(ContextData::new(flags, dev, false, 1)?));
+    let context_box = Box::new(LiveCheck::new(ContextData::new_non_primary(flags, dev)));
     let context_ptr = Box::into_raw(context_box);
     *pctx = context_ptr;
     push_context_stack(context_ptr)
@@ -105,7 +152,7 @@ pub(crate) unsafe fn destroy(ctx: *mut Context) -> Result<(), CUresult> {
         return Err(CUresult::CUDA_ERROR_INVALID_VALUE);
     }
     let ctx_ref = LiveCheck::as_result(ctx)?;
-    if ctx_ref.is_primary {
+    if let ContextVariant::Primary { .. } = ctx_ref.variant {
         return Err(CUresult::CUDA_ERROR_INVALID_CONTEXT);
     }
     CONTEXT_STACK.with(|stack| {
@@ -179,10 +226,7 @@ pub(crate) unsafe fn get_api_version(ctx: *mut Context, version: *mut u32) -> Re
     if ctx == ptr::null_mut() {
         return Err(CUresult::CUDA_ERROR_INVALID_CONTEXT);
     }
-    let ctx = LiveCheck::as_result(ctx)?;
-    if ctx.ref_count.load(Ordering::Acquire) == 0 {
-        return Err(CUresult::CUDA_ERROR_INVALID_CONTEXT);
-    }
+    //let ctx = LiveCheck::as_result(ctx)?;
     //TODO: query device for properties roughly matching CUDA API version
     *version = 3020;
     Ok(())

zluda/src/impl/dark_api.rs

@@ -121,20 +121,27 @@ impl CudaDarkApi for CudaDarkApiZluda {
         value: *mut c_void,
         dtor_callback: Option<extern "system" fn(cuda_types::CUcontext, *mut c_void, *mut c_void)>,
     ) -> CUresult {
-        with_context_or_current(cu_ctx, |ctx| {
-            let mut ctx_mutable = ctx
-                .mutable
-                .lock()
-                .map_err(|_| CUresult::CUDA_ERROR_UNKNOWN)?;
-            ctx_mutable.local_storage.insert(
-                key,
-                LocalStorageValue {
-                    value,
-                    _dtor_callback: dtor_callback,
-                },
-            );
-            Ok(())
-        })
+        unsafe fn context_local_storage_insert_impl(
+            cu_ctx: cuda_types::CUcontext,
+            key: *mut c_void,
+            value: *mut c_void,
+            dtor_callback: Option<
+                extern "system" fn(cuda_types::CUcontext, *mut c_void, *mut c_void),
+            >,
+        ) -> Result<(), CUresult> {
+            with_context_or_current(cu_ctx, |ctx| {
+                ctx.with_inner_mut(|ctx_mutable| {
+                    ctx_mutable.local_storage.insert(
+                        key,
+                        LocalStorageValue {
+                            value,
+                            _dtor_callback: dtor_callback,
+                        },
+                    );
+                })
+            })?
+        }
+        context_local_storage_insert_impl(cu_ctx, key, value, dtor_callback).into_cuda()
     }
 
     // TODO
@@ -143,29 +150,30 @@ impl CudaDarkApi for CudaDarkApiZluda {
     }
 
     unsafe extern "system" fn context_local_storage_get(
-        result: *mut *mut c_void,
+        cu_result: *mut *mut c_void,
         cu_ctx: cuda_types::CUcontext,
         key: *mut c_void,
     ) -> CUresult {
-        let mut cu_result = None;
-        let query_cu_result = with_context_or_current(cu_ctx, |ctx| {
-            let ctx_mutable = ctx
-                .mutable
-                .lock()
-                .map_err(|_| CUresult::CUDA_ERROR_UNKNOWN)?;
-            cu_result = ctx_mutable.local_storage.get(&key).map(|v| v.value);
-            Ok(())
-        });
-        if query_cu_result != CUresult::CUDA_SUCCESS {
-            query_cu_result
-        } else {
-            match cu_result {
-                Some(value) => {
-                    *result = value;
-                    CUresult::CUDA_SUCCESS
-                }
-                None => CUresult::CUDA_ERROR_INVALID_VALUE,
+        unsafe fn context_local_storage_get_impl(
+            cu_ctx: cuda_types::CUcontext,
+            key: *mut c_void,
+        ) -> Result<*mut c_void, CUresult> {
+            with_context_or_current(cu_ctx, |ctx| {
+                ctx.with_inner_mut(|ctx_mutable| {
+                    ctx_mutable
+                        .local_storage
+                        .get(&key)
+                        .map(|v| v.value)
+                        .ok_or(CUresult::CUDA_ERROR_INVALID_VALUE)
+                })?
+            })?
+        }
+        match context_local_storage_get_impl(cu_ctx, key) {
+            Ok(result) => {
+                *cu_result = result;
+                CUresult::CUDA_SUCCESS
             }
+            Err(err) => err,
         }
     }
 
@@ -386,14 +394,14 @@ impl CudaDarkApi for CudaDarkApiZluda {
     }
 }
 
-unsafe fn with_context_or_current(
+unsafe fn with_context_or_current<T>(
     ctx: CUcontext,
-    f: impl FnOnce(&context::ContextData) -> Result<(), CUresult>,
-) -> CUresult {
+    fn_: impl FnOnce(&context::ContextData) -> T,
+) -> Result<T, CUresult> {
     if ctx == ptr::null_mut() {
-        context::with_current(|c| f(c)).into_cuda()
+        context::with_current(|c| fn_(c))
     } else {
         let ctx = FromCuda::from_cuda(ctx);
-        LiveCheck::as_result(ctx).map(f).into_cuda()
+        Ok(fn_(LiveCheck::as_result(ctx)?))
     }
 }

zluda/src/impl/device.rs

@@ -1,6 +1,8 @@
+use super::context::{ContextInnerMutable, ContextVariant, PrimaryContextData};
 use super::{
-    context,  LiveCheck, GLOBAL_STATE,
+    context, LiveCheck, ZludaObject, GLOBAL_STATE
 };
+use crate::r#impl::context::ContextData;
 use crate::{r#impl::IntoCuda, hip_call_cuda};
 use crate::hip_call;
 use cuda_types::{CUdevice_attribute, CUdevprop, CUuuid_st, CUresult};
@@ -28,9 +30,7 @@ pub const COMPUTE_CAPABILITY_MINOR: u32 = 8;
 pub(crate) struct Device {
     pub(crate) compilation_mode: CompilationMode,
     pub(crate) comgr_isa: CString,
-    // Primary context is lazy-initialized, the mutex is here to secure retain
-    // from multiple threads
-    primary_context: Mutex<Option<context::Context>>,
+    primary_context: context::Context,
 }
 
 impl Device {
@@ -48,7 +48,7 @@ impl Device {
         Ok(Self {
             compilation_mode,
             comgr_isa,
-            primary_context: Mutex::new(None),
+            primary_context: LiveCheck::new(ContextData::new_primary(index as i32)),
         })
     }
 }
@@ -516,38 +516,29 @@ unsafe fn primary_ctx_get_or_retain(
     if pctx == ptr::null_mut() {
         return Err(CUresult::CUDA_ERROR_INVALID_VALUE);
     }
-    let ctx = primary_ctx(hip_dev, |ctx| {
-        let ctx = match ctx {
-            Some(ref mut ctx) => ctx,
-            None => {
-                ctx.insert(LiveCheck::new(context::ContextData::new(0, hip_dev, true, 0)?))
-            },
-        };
-        if increment_refcount {
-            ctx.as_mut_unchecked().ref_count.get_mut().add_assign(1);
+    let ctx = primary_ctx(hip_dev, |ctx, raw_ctx| {
+        if increment_refcount || ctx.ref_count == 0  {
+            ctx.ref_count += 1;
         }
-        Ok(ctx as *mut _)
+        Ok(raw_ctx.cast_mut())
     })??;
     *pctx = ctx;
     Ok(())
 }
 
 pub(crate) unsafe fn primary_ctx_release(hip_dev: hipDevice_t) -> Result<(), CUresult> {
-    primary_ctx(hip_dev, move |maybe_ctx| {
-        if let Some(ctx) = maybe_ctx {
-            let ctx_data = ctx.as_mut_unchecked();
-            let ref_count = ctx_data.ref_count.get_mut();
-            *ref_count -= 1;
-            if *ref_count == 0 {
-                //TODO: fix
-                //ctx.try_drop(false)
-                Ok(())
-            } else {
-                Ok(())
-            }
-        } else {
-            Err(CUresult::CUDA_ERROR_INVALID_CONTEXT)
+    primary_ctx(hip_dev, |ctx, _| {
+        if ctx.ref_count == 0 {
+            return Err(CUresult::CUDA_ERROR_INVALID_CONTEXT);
         }
+        ctx.ref_count -= 1;
+        if ctx.ref_count == 0 {
+            // Even if we encounter errors we can't really surface them
+            ctx.mutable.drop_with_result().ok();
+            ctx.mutable = ContextInnerMutable::new();
+            ctx.flags = 0;
+        }
+        Ok(())
     })?
 }
 
@@ -566,53 +557,43 @@ pub(crate) unsafe fn primary_ctx_set_flags(
     hip_dev: hipDevice_t,
     flags: ::std::os::raw::c_uint,
 ) -> Result<(), CUresult> {
-    primary_ctx(hip_dev, move |maybe_ctx| {
-        if let Some(ctx) = maybe_ctx {
-            let ctx = ctx.as_mut_unchecked();
-            ctx.flags = AtomicU32::new(flags);
-            Ok(())
-        } else {
-            Err(CUresult::CUDA_ERROR_INVALID_CONTEXT)
-        }
+    primary_ctx(hip_dev, |ctx, _| {
+        ctx.flags = flags;
+        // TODO: actually use flags
+        Ok(())
     })?
 }
 
 pub(crate) unsafe fn primary_ctx_get_state(
     hip_dev: hipDevice_t,
-    flags_ptr: *mut ::std::os::raw::c_uint,
-    active_ptr: *mut ::std::os::raw::c_int,
+    flags_ptr: *mut u32,
+    active_ptr: *mut i32,
 ) -> Result<(), CUresult> {
     if flags_ptr == ptr::null_mut() || active_ptr == ptr::null_mut() {
         return Err(CUresult::CUDA_ERROR_INVALID_VALUE);
     }
-    let maybe_flags = primary_ctx(hip_dev, move |maybe_ctx| {
-        if let Some(ctx) = maybe_ctx {
-            let ctx = ctx.as_mut_unchecked();
-            Some(*ctx.flags.get_mut())
-        } else {
-            None
-        }
+    let (flags, active) = primary_ctx(hip_dev, |ctx, _| {
+        (ctx.flags, (ctx.ref_count > 0) as i32)
     })?;
-    if let Some(flags) = maybe_flags {
-        *flags_ptr = flags;
-        *active_ptr = 1;
-    } else {
-        *flags_ptr = 0;
-        *active_ptr = 0;
-    }
+    *flags_ptr = flags;
+    *active_ptr = active;
     Ok(())
 }
 
 pub(crate) unsafe fn primary_ctx<T>(
     dev: hipDevice_t,
-    f: impl FnOnce(&mut Option<context::Context>) -> T,
+    fn_: impl FnOnce(&mut PrimaryContextData, *const LiveCheck<ContextData>) -> T,
 ) -> Result<T, CUresult> {
     let device = GLOBAL_STATE.get()?.device(dev)?;
-    let mut maybe_primary_context = device
-        .primary_context
-        .lock()
-        .map_err(|_| CUresult::CUDA_ERROR_UNKNOWN)?;
-    Ok(f(&mut maybe_primary_context))
+    let raw_ptr = &device.primary_context as *const _;
+    let context = device.primary_context.as_ref_unchecked();
+    match context.variant {
+        ContextVariant::Primary(ref mutex_over_primary_ctx) => {
+            let mut primary_ctx = mutex_over_primary_ctx.lock().map_err(|_| CUresult::CUDA_ERROR_UNKNOWN)?;
+            Ok(fn_(&mut primary_ctx, raw_ptr))
+        },
+        ContextVariant::NonPrimary(..) => Err(CUresult::CUDA_ERROR_UNKNOWN)
+    }
 }
 
 pub(crate) unsafe fn get_name(name: *mut i8, len: i32, device: i32) -> hipError_t {

zluda/src/impl/mod.rs

@@ -148,6 +148,10 @@ impl<T: ZludaObject> LiveCheck<T> {
         outer_ptr as *mut Self
     }
 
+    pub unsafe fn as_ref_unchecked(&self) -> & T {
+        &self.data
+    }
+
     pub unsafe fn as_mut_unchecked(&mut self) -> &mut T {
         &mut self.data
     }

zluda/src/impl/module.rs

@@ -31,13 +31,11 @@ impl ZludaObject for ModuleData {
         let deregistration_err = if !by_owner {
             if let Some(ctx) = self.owner {
                 let ctx = unsafe { LiveCheck::as_result(ctx.as_ptr())? };
-                let mut ctx_mutable = ctx
-                    .mutable
-                    .lock()
-                    .map_err(|_| CUresult::CUDA_ERROR_UNKNOWN)?;
-                ctx_mutable
-                    .modules
-                    .remove(&unsafe { LiveCheck::from_raw(self) });
+                ctx.with_inner_mut(|ctx_mutable| {
+                    ctx_mutable
+                        .modules
+                        .remove(&unsafe { LiveCheck::from_raw(self) });
+                })?;
             }
             Ok(())
         } else {
@@ -104,11 +102,9 @@ pub(crate) unsafe fn load_impl(
             isa,
             input,
         )?);
-        let mut ctx_mutable = ctx
-            .mutable
-            .lock()
-            .map_err(|_| CUresult::CUDA_ERROR_UNKNOWN)?;
-        ctx_mutable.modules.insert(module);
+        ctx.with_inner_mut(|ctx_mutable| {
+            ctx_mutable.modules.insert(module);
+        })?;
         *output = module;
         Ok(())
     })?

zluda/src/impl/stream.rs

@@ -21,13 +21,11 @@ impl ZludaObject for StreamData {
         if !by_owner {
             let ctx = unsafe { LiveCheck::as_result(self.ctx)? };
             {
-                let mut ctx_mutable = ctx
-                    .mutable
-                    .lock()
-                    .map_err(|_| CUresult::CUDA_ERROR_UNKNOWN)?;
-                ctx_mutable
-                    .streams
-                    .remove(&unsafe { LiveCheck::from_raw(&mut *self) });
+                ctx.with_inner_mut(|ctx_mutable| {
+                    ctx_mutable
+                        .streams
+                        .remove(&unsafe { LiveCheck::from_raw(&mut *self) });
+                })?;
             }
         }
         hip_call_cuda!(hipStreamDestroy(self.base));
@@ -59,11 +57,9 @@ pub(crate) unsafe fn create_with_priority(
         ctx: ptr::null_mut(),
     })));
     let ctx = context::with_current(|ctx| {
-        let mut ctx_mutable = ctx
-            .mutable
-            .lock()
-            .map_err(|_| CUresult::CUDA_ERROR_UNKNOWN)?;
-        ctx_mutable.streams.insert(stream);
+        ctx.with_inner_mut(|ctx_mutable| {
+            ctx_mutable.streams.insert(stream);
+        })?;
         Ok(LiveCheck::from_raw(ctx as *const _ as _))
     })??;
     (*stream).as_mut_unchecked().ctx = ctx;

zluda/tests/primary_context.rs

@@ -1,6 +1,6 @@
 use crate::common::CudaDriverFns;
 use cuda_types::*;
-
+use std::{mem, ptr};
 mod common;
 
 cuda_driver_test!(primary_context);
@@ -18,4 +18,47 @@ unsafe fn primary_context<T: CudaDriverFns>(cuda: T) {
         cuda.cuDevicePrimaryCtxSetFlags_v2(CUdevice_v1(0), 1),
         CUresult::CUDA_SUCCESS
     );
+    let mut primary_ctx = ptr::null_mut();
+    assert_eq!(
+        cuda.cuDevicePrimaryCtxRetain(&mut primary_ctx, CUdevice_v1(0)),
+        CUresult::CUDA_SUCCESS
+    );
+    assert_ne!(primary_ctx, ptr::null_mut());
+    let mut active_ctx = ptr::null_mut();
+    assert_eq!(
+        cuda.cuCtxGetCurrent(&mut active_ctx),
+        CUresult::CUDA_SUCCESS
+    );
+    assert_ne!(primary_ctx, active_ctx);
+    assert_eq!(
+        cuda.cuDevicePrimaryCtxGetState(CUdevice_v1(0), &mut flags, &mut active),
+        CUresult::CUDA_SUCCESS
+    );
+    assert_eq!((1, 1), (flags, active));
+    let mut buffer = mem::zeroed();
+    assert_eq!(
+        cuda.cuCtxPushCurrent_v2(primary_ctx),
+        CUresult::CUDA_SUCCESS
+    );
+    assert_eq!(cuda.cuMemAlloc_v2(&mut buffer, 4), CUresult::CUDA_SUCCESS);
+    assert_eq!(
+        cuda.cuDevicePrimaryCtxRelease_v2(CUdevice_v1(0)),
+        CUresult::CUDA_SUCCESS
+    );
+    assert_eq!(
+        cuda.cuDevicePrimaryCtxGetState(CUdevice_v1(0), &mut flags, &mut active),
+        CUresult::CUDA_SUCCESS
+    );
+    assert_ne!(
+        cuda.cuDevicePrimaryCtxRelease_v2(CUdevice_v1(0)),
+        CUresult::CUDA_SUCCESS
+    );
+    assert_eq!((0, 0), (flags, active));
+    // Already freed on context destruction
+    // TODO: reenable when we start tracking allocations inside context
+    //assert_ne!(cuda.cuMemFree_v2(buffer), CUresult::CUDA_SUCCESS);
+    assert_eq!(
+        cuda.cuDevicePrimaryCtxReset_v2(CUdevice_v1(0)),
+        CUresult::CUDA_SUCCESS
+    );
 }