diff --git a/examples/async-task.rs b/examples/async-task.rs
index 7d0ee86e03..d058fe54d5 100644
--- a/examples/async-task.rs
+++ b/examples/async-task.rs
@@ -15,7 +15,9 @@ mod app {
     use cortex_m_semihosting::{debug, hprintln};
 
     #[shared]
-    struct Shared {}
+    struct Shared {
+        a: u32,
+    }
 
     #[local]
     struct Local {}
@@ -25,11 +27,12 @@ mod app {
         hprintln!("init").unwrap();
 
         async_task::spawn().unwrap();
+        async_task2::spawn().unwrap();
 
-        (Shared {}, Local {})
+        (Shared { a: 0 }, Local {})
     }
 
-    #[idle]
+    #[idle(shared = [a])]
     fn idle(_: idle::Context) -> ! {
         // debug::exit(debug::EXIT_SUCCESS);
         loop {
@@ -38,10 +41,23 @@ mod app {
         }
     }
 
-    #[task]
-    async fn async_task(_cx: async_task::Context) {
+    #[task(binds = UART1, shared = [a])]
+    fn hw_task(cx: hw_task::Context) {
+        let hw_task::SharedResources { a } = cx.shared;
+        hprintln!("hello from hw").ok();
+    }
+
+    #[task(shared = [a])]
+    async fn async_task(cx: async_task::Context) {
+        let async_task::SharedResources { a } = cx.shared;
         hprintln!("hello from async").ok();
 
         debug::exit(debug::EXIT_SUCCESS);
     }
+
+    #[task(priority = 2, shared = [a])]
+    async fn async_task2(cx: async_task2::Context) {
+        let async_task2::SharedResources { a } = cx.shared;
+        hprintln!("hello from async2").ok();
+    }
 }
diff --git a/macros/src/bindings.rs b/macros/src/bindings.rs
index e69de29bb2..8b13789179 100644
--- a/macros/src/bindings.rs
+++ b/macros/src/bindings.rs
@@ -0,0 +1 @@
+
diff --git a/macros/src/codegen.rs b/macros/src/codegen.rs
index 0f68c34731..b490d7a501 100644
--- a/macros/src/codegen.rs
+++ b/macros/src/codegen.rs
@@ -19,6 +19,10 @@ mod shared_resources_struct;
 mod software_tasks;
 mod util;
 
+// TODO: organize codegen to actual parts of code
+// so `main::codegen` generates ALL the code for `fn main`,
+// `software_tasks::codegen` generates ALL the code for software tasks etc...
+
 #[allow(clippy::too_many_lines)]
 pub fn app(app: &App, analysis: &Analysis) -> TokenStream2 {
     let mut mod_app = vec![];
diff --git a/macros/src/codegen/async_dispatchers.rs b/macros/src/codegen/async_dispatchers.rs
index f428cef04f..d53d7b5e0c 100644
--- a/macros/src/codegen/async_dispatchers.rs
+++ b/macros/src/codegen/async_dispatchers.rs
@@ -13,7 +13,6 @@ pub fn codegen(app: &App, analysis: &Analysis) -> Vec<TokenStream2> {
     for (name, _) in app.software_tasks.iter() {
         let type_name = util::internal_task_ident(name, "F");
         let exec_name = util::internal_task_ident(name, "EXEC");
-        let prio_name = util::internal_task_ident(name, "PRIORITY");
 
         items.push(quote!(
             #[allow(non_camel_case_types)]
@@ -22,12 +21,6 @@ pub fn codegen(app: &App, analysis: &Analysis) -> Vec<TokenStream2> {
             static #exec_name:
                 rtic::RacyCell<rtic::export::executor::AsyncTaskExecutor<#type_name>> =
                     rtic::RacyCell::new(rtic::export::executor::AsyncTaskExecutor::new());
-
-            // The executors priority, this can be any value - we will overwrite it when we
-            // start a task
-            #[allow(non_upper_case_globals)]
-            static #prio_name: rtic::RacyCell<rtic::export::Priority> =
-                    unsafe { rtic::RacyCell::new(rtic::export::Priority::new(0)) };
         ));
     }
 
@@ -39,7 +32,6 @@ pub fn codegen(app: &App, analysis: &Analysis) -> Vec<TokenStream2> {
 
         for name in channel.tasks.iter() {
             let exec_name = util::internal_task_ident(name, "EXEC");
-            let prio_name = util::internal_task_ident(name, "PRIORITY");
             // let task = &app.software_tasks[name];
             // let cfgs = &task.cfgs;
             let executor_run_ident = util::executor_run_ident(name);
@@ -57,14 +49,9 @@ pub fn codegen(app: &App, analysis: &Analysis) -> Vec<TokenStream2> {
                 if !(&*#exec_name.get()).is_running() {
                     // TODO Fix this to be compare and swap
                     if #rq.load(core::sync::atomic::Ordering::Relaxed) {
-                         #rq.store(false, core::sync::atomic::Ordering::Relaxed);
+                        #rq.store(false, core::sync::atomic::Ordering::Relaxed);
 
-
-                        // The async executor needs a static priority
-                        #prio_name.get_mut().write(rtic::export::Priority::new(PRIORITY));
-                        let priority: &'static _ = &*#prio_name.get();
-
-                        (&mut *#exec_name.get_mut()).spawn(#name(#name::Context::new(priority)));
+                        (&mut *#exec_name.get_mut()).spawn(#name(#name::Context::new()));
                         #executor_run_ident.store(true, core::sync::atomic::Ordering::Relaxed);
                     }
                 }
diff --git a/macros/src/codegen/hardware_tasks.rs b/macros/src/codegen/hardware_tasks.rs
index 2a81d9a051..9ea5825b3d 100644
--- a/macros/src/codegen/hardware_tasks.rs
+++ b/macros/src/codegen/hardware_tasks.rs
@@ -41,22 +41,16 @@ pub fn codegen(
 
                 rtic::export::run(PRIORITY, || {
                     #name(
-                        #name::Context::new(&rtic::export::Priority::new(PRIORITY))
+                        #name::Context::new()
                     )
                 });
             }
         ));
 
-        let mut shared_needs_lt = false;
-        let mut local_needs_lt = false;
-
         // `${task}Locals`
         if !task.args.local_resources.is_empty() {
-            let (item, constructor) = local_resources_struct::codegen(
-                Context::HardwareTask(name),
-                &mut local_needs_lt,
-                app,
-            );
+            let (item, constructor) =
+                local_resources_struct::codegen(Context::HardwareTask(name), app);
 
             root.push(item);
 
@@ -65,24 +59,19 @@ pub fn codegen(
 
         // `${task}Resources`
         if !task.args.shared_resources.is_empty() {
-            let (item, constructor) = shared_resources_struct::codegen(
-                Context::HardwareTask(name),
-                &mut shared_needs_lt,
-                app,
-            );
+            let (item, constructor) =
+                shared_resources_struct::codegen(Context::HardwareTask(name), app);
 
             root.push(item);
 
             mod_app.push(constructor);
         }
 
-        root.push(module::codegen(
-            Context::HardwareTask(name),
-            shared_needs_lt,
-            local_needs_lt,
-            app,
-            analysis,
-        ));
+        // Module generation...
+
+        root.push(module::codegen(Context::HardwareTask(name), app, analysis));
+
+        // End module generation
 
         if !task.is_extern {
             let attrs = &task.attrs;
diff --git a/macros/src/codegen/idle.rs b/macros/src/codegen/idle.rs
index 98679399f9..a4f6325420 100644
--- a/macros/src/codegen/idle.rs
+++ b/macros/src/codegen/idle.rs
@@ -24,37 +24,27 @@ pub fn codegen(
     TokenStream2,
 ) {
     if let Some(idle) = &app.idle {
-        let mut shared_needs_lt = false;
-        let mut local_needs_lt = false;
         let mut mod_app = vec![];
         let mut root_idle = vec![];
 
         let name = &idle.name;
 
         if !idle.args.shared_resources.is_empty() {
-            let (item, constructor) =
-                shared_resources_struct::codegen(Context::Idle, &mut shared_needs_lt, app);
+            let (item, constructor) = shared_resources_struct::codegen(Context::Idle, app);
 
             root_idle.push(item);
             mod_app.push(constructor);
         }
 
         if !idle.args.local_resources.is_empty() {
-            let (item, constructor) =
-                local_resources_struct::codegen(Context::Idle, &mut local_needs_lt, app);
+            let (item, constructor) = local_resources_struct::codegen(Context::Idle, app);
 
             root_idle.push(item);
 
             mod_app.push(constructor);
         }
 
-        root_idle.push(module::codegen(
-            Context::Idle,
-            shared_needs_lt,
-            local_needs_lt,
-            app,
-            analysis,
-        ));
+        root_idle.push(module::codegen(Context::Idle, app, analysis));
 
         let attrs = &idle.attrs;
         let context = &idle.context;
@@ -71,7 +61,7 @@ pub fn codegen(
         ));
 
         let call_idle = quote!(#name(
-            #name::Context::new(&rtic::export::Priority::new(0))
+            #name::Context::new()
         ));
 
         (mod_app, root_idle, user_idle, call_idle)
diff --git a/macros/src/codegen/init.rs b/macros/src/codegen/init.rs
index c7b871234e..bbde4f275f 100644
--- a/macros/src/codegen/init.rs
+++ b/macros/src/codegen/init.rs
@@ -91,8 +91,7 @@ pub fn codegen(app: &App, analysis: &Analysis) -> CodegenResult {
 
     // `${task}Locals`
     if !init.args.local_resources.is_empty() {
-        let (item, constructor) =
-            local_resources_struct::codegen(Context::Init, &mut local_needs_lt, app);
+        let (item, constructor) = local_resources_struct::codegen(Context::Init, app);
 
         root_init.push(item);
 
@@ -103,13 +102,7 @@ pub fn codegen(app: &App, analysis: &Analysis) -> CodegenResult {
         let (shared_resources, local_resources) = #name(#name::Context::new(core.into()));
     };
 
-    root_init.push(module::codegen(
-        Context::Init,
-        false,
-        local_needs_lt,
-        app,
-        analysis,
-    ));
+    root_init.push(module::codegen(Context::Init, app, analysis));
 
     (mod_app, root_init, user_init, call_init)
 }
diff --git a/macros/src/codegen/local_resources_struct.rs b/macros/src/codegen/local_resources_struct.rs
index 6bcf4fadc8..a0413f9cfa 100644
--- a/macros/src/codegen/local_resources_struct.rs
+++ b/macros/src/codegen/local_resources_struct.rs
@@ -8,7 +8,7 @@ use quote::quote;
 use crate::codegen::util;
 
 /// Generates local resources structs
-pub fn codegen(ctxt: Context, needs_lt: &mut bool, app: &App) -> (TokenStream2, TokenStream2) {
+pub fn codegen(ctxt: Context, app: &App) -> (TokenStream2, TokenStream2) {
     let mut lt = None;
 
     let resources = match ctxt {
@@ -74,16 +74,14 @@ pub fn codegen(ctxt: Context, needs_lt: &mut bool, app: &App) -> (TokenStream2,
     }
 
     if lt.is_some() {
-        *needs_lt = true;
-
         // The struct could end up empty due to `cfg`s leading to an error due to `'a` being unused
         if has_cfgs {
             fields.push(quote!(
                 #[doc(hidden)]
-                pub __marker__: core::marker::PhantomData<&'a ()>
+                pub __rtic_internal_marker: ::core::marker::PhantomData<&'a ()>
             ));
 
-            values.push(quote!(__marker__: core::marker::PhantomData));
+            values.push(quote!(__rtic_internal_marker: ::core::marker::PhantomData));
         }
     }
 
diff --git a/macros/src/codegen/module.rs b/macros/src/codegen/module.rs
index 7bbfdf37c2..a64abd8a74 100644
--- a/macros/src/codegen/module.rs
+++ b/macros/src/codegen/module.rs
@@ -4,13 +4,7 @@ use proc_macro2::TokenStream as TokenStream2;
 use quote::quote;
 
 #[allow(clippy::too_many_lines)]
-pub fn codegen(
-    ctxt: Context,
-    shared_resources_tick: bool,
-    local_resources_tick: bool,
-    app: &App,
-    analysis: &Analysis,
-) -> TokenStream2 {
+pub fn codegen(ctxt: Context, app: &App, analysis: &Analysis) -> TokenStream2 {
     let mut items = vec![];
     let mut module_items = vec![];
     let mut fields = vec![];
@@ -20,7 +14,6 @@ pub fn codegen(
 
     let name = ctxt.ident(app);
 
-    let mut lt = None;
     match ctxt {
         Context::Init => {
             fields.push(quote!(
@@ -39,10 +32,9 @@ pub fn codegen(
                 values.push(quote!(device: #device::Peripherals::steal()));
             }
 
-            lt = Some(quote!('a));
             fields.push(quote!(
                 /// Critical section token for init
-                pub cs: rtic::export::CriticalSection<#lt>
+                pub cs: rtic::export::CriticalSection<'a>
             ));
 
             values.push(quote!(cs: rtic::export::CriticalSection::new()));
@@ -55,12 +47,6 @@ pub fn codegen(
 
     if ctxt.has_local_resources(app) {
         let ident = util::local_resources_ident(ctxt, app);
-        let lt = if local_resources_tick {
-            lt = Some(quote!('a));
-            Some(quote!('a))
-        } else {
-            None
-        };
 
         module_items.push(quote!(
             #[doc(inline)]
@@ -69,7 +55,7 @@ pub fn codegen(
 
         fields.push(quote!(
             /// Local Resources this task has access to
-            pub local: #name::LocalResources<#lt>
+            pub local: #name::LocalResources<'a>
         ));
 
         values.push(quote!(local: #name::LocalResources::new()));
@@ -77,12 +63,6 @@ pub fn codegen(
 
     if ctxt.has_shared_resources(app) {
         let ident = util::shared_resources_ident(ctxt, app);
-        let lt = if shared_resources_tick {
-            lt = Some(quote!('a));
-            Some(quote!('a))
-        } else {
-            None
-        };
 
         module_items.push(quote!(
             #[doc(inline)]
@@ -91,15 +71,10 @@ pub fn codegen(
 
         fields.push(quote!(
             /// Shared Resources this task has access to
-            pub shared: #name::SharedResources<#lt>
+            pub shared: #name::SharedResources<'a>
         ));
 
-        let priority = if ctxt.is_init() {
-            None
-        } else {
-            Some(quote!(priority))
-        };
-        values.push(quote!(shared: #name::SharedResources::new(#priority)));
+        values.push(quote!(shared: #name::SharedResources::new()));
     }
 
     let doc = match ctxt {
@@ -122,12 +97,6 @@ pub fn codegen(
         None
     };
 
-    let priority = if ctxt.is_init() {
-        None
-    } else {
-        Some(quote!(priority: &#lt rtic::export::Priority))
-    };
-
     let internal_context_name = util::internal_task_ident(name, "Context");
 
     items.push(quote!(
@@ -135,15 +104,18 @@ pub fn codegen(
         /// Execution context
         #[allow(non_snake_case)]
         #[allow(non_camel_case_types)]
-        pub struct #internal_context_name<#lt> {
+        pub struct #internal_context_name<'a> {
+            #[doc(hidden)]
+            __rtic_internal_p: ::core::marker::PhantomData<&'a ()>,
             #(#fields,)*
         }
 
         #(#cfgs)*
-        impl<#lt> #internal_context_name<#lt> {
+        impl<'a> #internal_context_name<'a> {
             #[inline(always)]
-            pub unsafe fn new(#core #priority) -> Self {
+            pub unsafe fn new(#core) -> Self {
                 #internal_context_name {
+                    __rtic_internal_p: ::core::marker::PhantomData,
                     #(#values,)*
                 }
             }
diff --git a/macros/src/codegen/shared_resources.rs b/macros/src/codegen/shared_resources.rs
index b63e7432d6..5c54fb99b2 100644
--- a/macros/src/codegen/shared_resources.rs
+++ b/macros/src/codegen/shared_resources.rs
@@ -57,19 +57,14 @@ pub fn codegen(
                 #[allow(non_camel_case_types)]
                 #(#cfgs)*
                 pub struct #shared_name<'a> {
-                    priority: &'a Priority,
+                    __rtic_internal_p: ::core::marker::PhantomData<&'a ()>,
                 }
 
                 #(#cfgs)*
                 impl<'a> #shared_name<'a> {
                     #[inline(always)]
-                    pub unsafe fn new(priority: &'a Priority) -> Self {
-                        #shared_name { priority }
-                    }
-
-                    #[inline(always)]
-                    pub unsafe fn priority(&self) -> &Priority {
-                        self.priority
+                    pub unsafe fn new() -> Self {
+                        #shared_name { __rtic_internal_p: ::core::marker::PhantomData }
                     }
                 }
             ));
@@ -104,8 +99,6 @@ pub fn codegen(
         quote!()
     } else {
         quote!(mod shared_resources {
-            use rtic::export::Priority;
-
             #(#mod_resources)*
         })
     };
diff --git a/macros/src/codegen/shared_resources_struct.rs b/macros/src/codegen/shared_resources_struct.rs
index 1d46aa4e4c..de597cab16 100644
--- a/macros/src/codegen/shared_resources_struct.rs
+++ b/macros/src/codegen/shared_resources_struct.rs
@@ -5,7 +5,7 @@ use quote::quote;
 use crate::codegen::util;
 
 /// Generate shared resources structs
-pub fn codegen(ctxt: Context, needs_lt: &mut bool, app: &App) -> (TokenStream2, TokenStream2) {
+pub fn codegen(ctxt: Context, app: &App) -> (TokenStream2, TokenStream2) {
     let mut lt = None;
 
     let resources = match ctxt {
@@ -72,7 +72,7 @@ pub fn codegen(ctxt: Context, needs_lt: &mut bool, app: &App) -> (TokenStream2,
 
             values.push(quote!(
                 #(#cfgs)*
-                #name: shared_resources::#shared_name::new(priority)
+                #name: shared_resources::#shared_name::new()
 
             ));
 
@@ -93,8 +93,6 @@ pub fn codegen(ctxt: Context, needs_lt: &mut bool, app: &App) -> (TokenStream2,
     }
 
     if lt.is_some() {
-        *needs_lt = true;
-
         // The struct could end up empty due to `cfg`s leading to an error due to `'a` being unused
         if has_cfgs {
             fields.push(quote!(
@@ -117,15 +115,10 @@ pub fn codegen(ctxt: Context, needs_lt: &mut bool, app: &App) -> (TokenStream2,
         }
     );
 
-    let arg = if ctxt.is_init() {
-        None
-    } else {
-        Some(quote!(priority: &#lt rtic::export::Priority))
-    };
     let constructor = quote!(
         impl<#lt> #ident<#lt> {
             #[inline(always)]
-            pub unsafe fn new(#arg) -> Self {
+            pub unsafe fn new() -> Self {
                 #ident {
                     #(#values,)*
                 }
diff --git a/macros/src/codegen/software_tasks.rs b/macros/src/codegen/software_tasks.rs
index b2b468ca9a..350c1e6009 100644
--- a/macros/src/codegen/software_tasks.rs
+++ b/macros/src/codegen/software_tasks.rs
@@ -36,16 +36,11 @@ pub fn codegen(
         ));
 
         // `${task}Resources`
-        let mut shared_needs_lt = false;
-        let mut local_needs_lt = false;
 
         // `${task}Locals`
         if !task.args.local_resources.is_empty() {
-            let (item, constructor) = local_resources_struct::codegen(
-                Context::SoftwareTask(name),
-                &mut local_needs_lt,
-                app,
-            );
+            let (item, constructor) =
+                local_resources_struct::codegen(Context::SoftwareTask(name), app);
 
             root.push(item);
 
@@ -53,11 +48,8 @@ pub fn codegen(
         }
 
         if !task.args.shared_resources.is_empty() {
-            let (item, constructor) = shared_resources_struct::codegen(
-                Context::SoftwareTask(name),
-                &mut shared_needs_lt,
-                app,
-            );
+            let (item, constructor) =
+                shared_resources_struct::codegen(Context::SoftwareTask(name), app);
 
             root.push(item);
 
@@ -69,17 +61,12 @@ pub fn codegen(
             let attrs = &task.attrs;
             let cfgs = &task.cfgs;
             let stmts = &task.stmts;
-            let context_lifetime = if shared_needs_lt || local_needs_lt {
-                quote!(<'static>)
-            } else {
-                quote!()
-            };
 
             user_tasks.push(quote!(
                 #(#attrs)*
                 #(#cfgs)*
                 #[allow(non_snake_case)]
-                async fn #name(#context: #name::Context #context_lifetime) {
+                async fn #name(#context: #name::Context<'static>) {
                     use rtic::Mutex as _;
                     use rtic::mutex::prelude::*;
 
@@ -88,13 +75,7 @@ pub fn codegen(
             ));
         }
 
-        root.push(module::codegen(
-            Context::SoftwareTask(name),
-            shared_needs_lt,
-            local_needs_lt,
-            app,
-            analysis,
-        ));
+        root.push(module::codegen(Context::SoftwareTask(name), app, analysis));
     }
 
     (mod_app, root, user_tasks)
diff --git a/macros/src/codegen/util.rs b/macros/src/codegen/util.rs
index aa720c0e5f..a071ca279d 100644
--- a/macros/src/codegen/util.rs
+++ b/macros/src/codegen/util.rs
@@ -17,10 +17,10 @@ pub fn impl_mutex(
     ceiling: u8,
     ptr: &TokenStream2,
 ) -> TokenStream2 {
-    let (path, priority) = if resources_prefix {
-        (quote!(shared_resources::#name), quote!(self.priority()))
+    let path = if resources_prefix {
+        quote!(shared_resources::#name)
     } else {
-        (quote!(#name), quote!(self.priority))
+        quote!(#name)
     };
 
     let device = &app.args.device;
@@ -38,7 +38,6 @@ pub fn impl_mutex(
                 unsafe {
                     rtic::export::lock(
                         #ptr,
-                        #priority,
                         CEILING,
                         #device::NVIC_PRIO_BITS,
                         &#masks_name,
diff --git a/rust-toolchain.toml b/rust-toolchain.toml
index bbd57bcb24..e28b55de64 100644
--- a/rust-toolchain.toml
+++ b/rust-toolchain.toml
@@ -1,4 +1,4 @@
 [toolchain]
 channel = "nightly"
 components = [ "rust-src", "rustfmt", "llvm-tools-preview" ]
-targets = [ "thumbv7em-none-eabihf" ]
+targets = [ "thumbv6m-none-eabi", "thumbv7m-none-eabi" ]
diff --git a/src/export.rs b/src/export.rs
index 2cc031e9e5..49ebd878ef 100644
--- a/src/export.rs
+++ b/src/export.rs
@@ -163,38 +163,6 @@ impl Barrier {
     }
 }
 
-// Newtype over `Cell` that forbids mutation through a shared reference
-pub struct Priority {
-    inner: Cell<u8>,
-}
-
-impl Priority {
-    /// Create a new Priority
-    ///
-    /// # Safety
-    ///
-    /// Will overwrite the current Priority
-    #[inline(always)]
-    pub const unsafe fn new(value: u8) -> Self {
-        Priority {
-            inner: Cell::new(value),
-        }
-    }
-
-    /// Change the current priority to `value`
-    // These two methods are used by `lock` (see below) but can't be used from the RTIC application
-    #[inline(always)]
-    fn set(&self, value: u8) {
-        self.inner.set(value);
-    }
-
-    /// Get the current priority
-    #[inline(always)]
-    fn get(&self) -> u8 {
-        self.inner.get()
-    }
-}
-
 /// Const helper to check architecture
 pub const fn have_basepri() -> bool {
     #[cfg(have_basepri)]
@@ -260,30 +228,20 @@ where
 #[inline(always)]
 pub unsafe fn lock<T, R, const M: usize>(
     ptr: *mut T,
-    priority: &Priority,
     ceiling: u8,
     nvic_prio_bits: u8,
     _mask: &[Mask<M>; 3],
     f: impl FnOnce(&mut T) -> R,
 ) -> R {
-    let current = priority.get();
-
-    if current < ceiling {
-        if ceiling == (1 << nvic_prio_bits) {
-            priority.set(u8::max_value());
-            let r = interrupt::free(|_| f(&mut *ptr));
-            priority.set(current);
-            r
-        } else {
-            priority.set(ceiling);
-            basepri::write(logical2hw(ceiling, nvic_prio_bits));
-            let r = f(&mut *ptr);
-            basepri::write(logical2hw(current, nvic_prio_bits));
-            priority.set(current);
-            r
-        }
+    if ceiling == (1 << nvic_prio_bits) {
+        let r = interrupt::free(|_| f(&mut *ptr));
+        r
     } else {
-        f(&mut *ptr)
+        let current = basepri::read();
+        basepri::write(logical2hw(ceiling, nvic_prio_bits));
+        let r = f(&mut *ptr);
+        basepri::write(logical2hw(current, nvic_prio_bits));
+        r
     }
 }
 
@@ -335,40 +293,29 @@ pub unsafe fn lock<T, R, const M: usize>(
 #[inline(always)]
 pub unsafe fn lock<T, R, const M: usize>(
     ptr: *mut T,
-    priority: &Priority,
     ceiling: u8,
     _nvic_prio_bits: u8,
     masks: &[Mask<M>; 3],
     f: impl FnOnce(&mut T) -> R,
 ) -> R {
-    let current = priority.get();
-    if current < ceiling {
-        if ceiling >= 4 {
-            // safe to manipulate outside critical section
-            priority.set(ceiling);
-            // execute closure under protection of raised system ceiling
-            let r = interrupt::free(|_| f(&mut *ptr));
-            // safe to manipulate outside critical section
-            priority.set(current);
-            r
-        } else {
-            // safe to manipulate outside critical section
-            priority.set(ceiling);
-            let mask = compute_mask(current, ceiling, masks);
-            clear_enable_mask(mask);
-
-            // execute closure under protection of raised system ceiling
-            let r = f(&mut *ptr);
-
-            set_enable_mask(mask);
-
-            // safe to manipulate outside critical section
-            priority.set(current);
-            r
-        }
+    if ceiling >= 4 {
+        // safe to manipulate outside critical section
+        // execute closure under protection of raised system ceiling
+        let r = interrupt::free(|_| f(&mut *ptr));
+        // safe to manipulate outside critical section
+        r
     } else {
-        // execute closure without raising system ceiling
-        f(&mut *ptr)
+        // safe to manipulate outside critical section
+        let mask = compute_mask(0, ceiling, masks);
+        clear_enable_mask(mask);
+
+        // execute closure under protection of raised system ceiling
+        let r = f(&mut *ptr);
+
+        set_enable_mask(mask);
+
+        // safe to manipulate outside critical section
+        r
     }
 }