Fix ProcessArray

Current pattern for process array is UB as both the scheduler and process loading logic have concurrent &mut references to it.

This change adds Cells internally. It also adds in new wrapper types / constructor methods so that boards do not need to be so aware of the exact types they are allocating. This makes future changes to the main process array not need to touch every board (like this has to).

Change-Id: I8f200e0051af618076c16b0d512bf20863342769

Author: Lawrence Esswood

boards/apollo3/redboard_artemis_nano/src/main.rs

@@ -42,7 +42,7 @@ mod tests;
 const NUM_PROCS: usize = 4;
 
 // Actual memory for holding the active process structures.
-static mut PROCESSES: [Option<&'static dyn kernel::process::Process>; NUM_PROCS] = [None; 4];
+static mut PROCESSES: kernel::ProcessArray<NUM_PROCS> = kernel::Kernel::init_process_array();
 
 // Static reference to chip for panic dumps.
 static mut CHIP: Option<&'static apollo3::chip::Apollo3<Apollo3DefaultPeripherals>> = None;
@@ -435,7 +435,6 @@ unsafe fn setup() -> (
             core::ptr::addr_of_mut!(_sappmem),
             core::ptr::addr_of!(_eappmem) as usize - core::ptr::addr_of!(_sappmem) as usize,
         ),
-        &mut *addr_of_mut!(PROCESSES),
         &FAULT_RESPONSE,
         &process_mgmt_cap,
     )

boards/arty_e21/src/main.rs

@@ -36,8 +36,7 @@ const FAULT_RESPONSE: capsules_system::process_policies::PanicFaultPolicy =
     capsules_system::process_policies::PanicFaultPolicy {};
 
 // Actual memory for holding the active process structures.
-static mut PROCESSES: [Option<&'static dyn kernel::process::Process>; NUM_PROCS] =
-    [None, None, None, None];
+static mut PROCESSES: kernel::ProcessArray<NUM_PROCS> = kernel::Kernel::init_process_array();
 
 // Reference to the chip for panic dumps.
 static mut CHIP: Option<&'static arty_e21_chip::chip::ArtyExx<ArtyExxDefaultPeripherals>> = None;
@@ -289,7 +288,6 @@ unsafe fn start() -> (
             core::ptr::addr_of_mut!(_sappmem),
             core::ptr::addr_of!(_eappmem) as usize - core::ptr::addr_of!(_sappmem) as usize,
         ),
-        &mut *addr_of_mut!(PROCESSES),
         &FAULT_RESPONSE,
         &process_mgmt_cap,
     )

boards/clue_nrf52840/src/main.rs

@@ -110,8 +110,7 @@ const FAULT_RESPONSE: capsules_system::process_policies::StopWithDebugFaultPolic
 // Number of concurrent processes this platform supports.
 const NUM_PROCS: usize = 8;
 
-static mut PROCESSES: [Option<&'static dyn kernel::process::Process>; NUM_PROCS] =
-    [None; NUM_PROCS];
+static mut PROCESSES: kernel::ProcessArray<NUM_PROCS> = kernel::Kernel::init_process_array();
 
 static mut CHIP: Option<&'static nrf52840::chip::NRF52<Nrf52840DefaultPeripherals>> = None;
 static mut PROCESS_PRINTER: Option<&'static capsules_system::process_printer::ProcessPrinterText> =
@@ -827,7 +826,6 @@ unsafe fn start() -> (
             core::ptr::addr_of_mut!(_sappmem),
             core::ptr::addr_of!(_eappmem) as usize - core::ptr::addr_of!(_sappmem) as usize,
         ),
-        &mut *addr_of_mut!(PROCESSES),
         &FAULT_RESPONSE,
         &process_management_capability,
     )

boards/components/src/loader/sequential.rs

@@ -38,7 +38,6 @@ pub struct ProcessLoaderSequentialComponent<
     const NUM_PROCS: usize,
 > {
     checker: &'static kernel::process::ProcessCheckerMachine,
-    processes: &'static mut [Option<&'static dyn kernel::process::Process>],
     kernel: &'static kernel::Kernel,
     chip: &'static C,
     fault_policy: &'static dyn kernel::process::ProcessFaultPolicy,
@@ -51,7 +50,6 @@ impl<C: Chip, D: ProcessStandardDebug, const NUM_PROCS: usize>
 {
     pub fn new(
         checker: &'static kernel::process::ProcessCheckerMachine,
-        processes: &'static mut [Option<&'static dyn kernel::process::Process>],
         kernel: &'static kernel::Kernel,
         chip: &'static C,
         fault_policy: &'static dyn kernel::process::ProcessFaultPolicy,
@@ -60,7 +58,6 @@ impl<C: Chip, D: ProcessStandardDebug, const NUM_PROCS: usize>
     ) -> Self {
         Self {
             checker,
-            processes,
             kernel,
             chip,
             fault_policy,
@@ -87,39 +84,22 @@ impl<C: Chip, D: ProcessStandardDebug, const NUM_PROCS: usize> Component
         const ARRAY_REPEAT_VALUE: Option<kernel::process::ProcessBinary> = None;
         let process_binary_array = s.1.write([ARRAY_REPEAT_VALUE; NUM_PROCS]);
 
-        // These symbols are defined in the standard Tock linker script.
-        extern "C" {
-            /// Beginning of the ROM region containing app images.
-            static _sapps: u8;
-            /// End of the ROM region containing app images.
-            static _eapps: u8;
-            /// Beginning of the RAM region for app memory.
-            static mut _sappmem: u8;
-            /// End of the RAM region for app memory.
-            static _eappmem: u8;
-        }
+        let (flash, ram) = unsafe { kernel::process_loading::get_mems() };
 
-        let loader = unsafe {
+        let loader =
             s.0.write(kernel::process::SequentialProcessLoaderMachine::new(
                 self.checker,
-                *core::ptr::addr_of_mut!(self.processes),
                 process_binary_array,
                 self.kernel,
                 self.chip,
-                core::slice::from_raw_parts(
-                    core::ptr::addr_of!(_sapps),
-                    core::ptr::addr_of!(_eapps) as usize - core::ptr::addr_of!(_sapps) as usize,
-                ),
-                core::slice::from_raw_parts_mut(
-                    core::ptr::addr_of_mut!(_sappmem),
-                    core::ptr::addr_of!(_eappmem) as usize - core::ptr::addr_of!(_sappmem) as usize,
-                ),
+                flash,
+                ram,
                 self.fault_policy,
                 self.storage_policy,
                 self.appid_policy,
                 &proc_manage_cap,
-            ))
-        };
+            ));
+
         self.checker.set_client(loader);
         loader.register();
         loader.start();

boards/components/src/sched/cooperative.rs

@@ -17,8 +17,8 @@
 
 use core::mem::MaybeUninit;
 use kernel::component::Component;
-use kernel::process::Process;
 use kernel::scheduler::cooperative::{CoopProcessNode, CooperativeSched};
+use kernel::ProcEntry;
 
 #[macro_export]
 macro_rules! cooperative_component_static {
@@ -34,13 +34,11 @@ macro_rules! cooperative_component_static {
 }
 
 pub struct CooperativeComponent<const NUM_PROCS: usize> {
-    processes: &'static [Option<&'static dyn Process>],
+    processes: &'static [ProcEntry],
 }
 
 impl<const NUM_PROCS: usize> CooperativeComponent<NUM_PROCS> {
-    pub fn new(
-        processes: &'static [Option<&'static dyn Process>],
-    ) -> CooperativeComponent<NUM_PROCS> {
+    pub fn new(processes: &'static [ProcEntry]) -> CooperativeComponent<NUM_PROCS> {
         CooperativeComponent { processes }
     }
 }
@@ -59,7 +57,7 @@ impl<const NUM_PROCS: usize> Component for CooperativeComponent<NUM_PROCS> {
         let nodes = static_buffer.1.write([UNINIT; NUM_PROCS]);
 
         for (i, node) in nodes.iter_mut().enumerate() {
-            let init_node = node.write(CoopProcessNode::new(&self.processes[i]));
+            let init_node = node.write(CoopProcessNode::new(&self.processes[i].proc_ref));
             scheduler.processes.push_head(init_node);
         }
         scheduler

boards/components/src/sched/mlfq.rs

@@ -14,8 +14,8 @@ use core::mem::MaybeUninit;
 use capsules_core::virtualizers::virtual_alarm::{MuxAlarm, VirtualMuxAlarm};
 use kernel::component::Component;
 use kernel::hil::time;
-use kernel::process::Process;
 use kernel::scheduler::mlfq::{MLFQProcessNode, MLFQSched};
+use kernel::ProcEntry;
 
 #[macro_export]
 macro_rules! mlfq_component_static {
@@ -39,13 +39,13 @@ macro_rules! mlfq_component_static {
 
 pub struct MLFQComponent<A: 'static + time::Alarm<'static>, const NUM_PROCS: usize> {
     alarm_mux: &'static MuxAlarm<'static, A>,
-    processes: &'static [Option<&'static dyn Process>],
+    processes: &'static [ProcEntry],
 }
 
 impl<A: 'static + time::Alarm<'static>, const NUM_PROCS: usize> MLFQComponent<A, NUM_PROCS> {
     pub fn new(
         alarm_mux: &'static MuxAlarm<'static, A>,
-        processes: &'static [Option<&'static dyn Process>],
+        processes: &'static [ProcEntry],
     ) -> MLFQComponent<A, NUM_PROCS> {
         MLFQComponent {
             alarm_mux,
@@ -74,7 +74,7 @@ impl<A: 'static + time::Alarm<'static>, const NUM_PROCS: usize> Component
         let nodes = static_buffer.2.write([UNINIT; NUM_PROCS]);
 
         for (i, node) in nodes.iter_mut().enumerate() {
-            let init_node = node.write(MLFQProcessNode::new(&self.processes[i]));
+            let init_node = node.write(MLFQProcessNode::new(&self.processes[i].proc_ref));
             scheduler.processes[0].push_head(init_node);
         }
         scheduler

boards/components/src/sched/round_robin.rs

@@ -17,9 +17,10 @@
 // Last modified: 03/31/2020
 
 use core::mem::MaybeUninit;
+use kernel::collections::list::ListLink;
 use kernel::component::Component;
-use kernel::process::Process;
 use kernel::scheduler::round_robin::{RoundRobinProcessNode, RoundRobinSched};
+use kernel::ProcEntry;
 
 #[macro_export]
 macro_rules! round_robin_component_static {
@@ -36,13 +37,11 @@ macro_rules! round_robin_component_static {
 }
 
 pub struct RoundRobinComponent<const NUM_PROCS: usize> {
-    processes: &'static [Option<&'static dyn Process>],
+    processes: &'static [ProcEntry],
 }
 
 impl<const NUM_PROCS: usize> RoundRobinComponent<NUM_PROCS> {
-    pub fn new(
-        processes: &'static [Option<&'static dyn Process>],
-    ) -> RoundRobinComponent<NUM_PROCS> {
+    pub fn new(processes: &'static [ProcEntry]) -> RoundRobinComponent<NUM_PROCS> {
         RoundRobinComponent { processes }
     }
 }

boards/esp32-c3-devkitM-1/src/main.rs

@@ -35,8 +35,7 @@ const NUM_PROCS: usize = 4;
 //
 // Actual memory for holding the active process structures. Need an empty list
 // at least.
-static mut PROCESSES: [Option<&'static dyn kernel::process::Process>; NUM_PROCS] =
-    [None; NUM_PROCS];
+static mut PROCESSES: kernel::ProcessArray<NUM_PROCS> = kernel::Kernel::init_process_array();
 
 // Reference to the chip for panic dumps.
 static mut CHIP: Option<&'static esp32_c3::chip::Esp32C3<Esp32C3DefaultPeripherals>> = None;
@@ -315,7 +314,6 @@ unsafe fn setup() -> (
             core::ptr::addr_of_mut!(_sappmem),
             core::ptr::addr_of!(_eappmem) as usize - core::ptr::addr_of!(_sappmem) as usize,
         ),
-        &mut *addr_of_mut!(PROCESSES),
         &FAULT_RESPONSE,
         &process_mgmt_cap,
     )

boards/hail/src/main.rs

@@ -39,8 +39,7 @@ mod test_take_map_cell;
 const NUM_PROCS: usize = 20;
 
 // Actual memory for holding the active process structures.
-static mut PROCESSES: [Option<&'static dyn kernel::process::Process>; NUM_PROCS] =
-    [None; NUM_PROCS];
+static mut PROCESSES: kernel::ProcessArray<NUM_PROCS> = kernel::Kernel::init_process_array();
 
 static mut CHIP: Option<&'static sam4l::chip::Sam4l<Sam4lDefaultPeripherals>> = None;
 static mut PROCESS_PRINTER: Option<&'static capsules_system::process_printer::ProcessPrinterText> =
@@ -550,7 +549,6 @@ unsafe fn start() -> (
             core::ptr::addr_of_mut!(_sappmem),
             core::ptr::addr_of!(_eappmem) as usize - core::ptr::addr_of!(_sappmem) as usize,
         ),
-        &mut *addr_of_mut!(PROCESSES),
         fault_policy,
         &process_management_capability,
     )

boards/hifive1/src/main.rs

@@ -36,8 +36,7 @@ pub const NUM_PROCS: usize = 4;
 //
 // Actual memory for holding the active process structures. Need an empty list
 // at least.
-static mut PROCESSES: [Option<&'static dyn kernel::process::Process>; NUM_PROCS] =
-    [None; NUM_PROCS];
+static mut PROCESSES: kernel::ProcessArray<NUM_PROCS> = kernel::Kernel::init_process_array();
 
 // Reference to the chip for panic dumps.
 static mut CHIP: Option<&'static e310_g002::chip::E310x<E310G002DefaultPeripherals>> = None;
@@ -165,7 +164,6 @@ fn load_processes_not_inlined<C: Chip>(board_kernel: &'static Kernel, chip: &'st
         chip,
         app_flash,
         app_memory,
-        unsafe { &mut *addr_of_mut!(PROCESSES) },
         &FAULT_RESPONSE,
         &process_mgmt_cap,
     )