Switch Context::actions to RwLock

src/context/context.rs

@@ -241,7 +241,7 @@ pub struct Context {
     /// The open files in the scheme
     pub files: Arc<RwLock<Vec<Option<FileDescriptor>>>>,
     /// Signal actions
-    pub actions: Arc<Mutex<Vec<(SigAction, usize)>>>,
+    pub actions: Arc<RwLock<Vec<(SigAction, usize)>>>,
     /// The pointer to the user-space registers, saved after certain
     /// interrupts. This pointer is somewhere inside kstack, and the
     /// kstack address at the time of creation is the first element in
@@ -295,7 +295,7 @@ impl Context {
             name: Arc::new(RwLock::new(String::new().into_boxed_str())),
             cwd: Arc::new(RwLock::new(Vec::new())),
             files: Arc::new(RwLock::new(Vec::new())),
-            actions: Arc::new(Mutex::new(vec![(
+            actions: Arc::new(RwLock::new(vec![(
                 SigAction {
                     sa_handler: unsafe { mem::transmute(SIG_DFL) },
                     sa_mask: [0; 2],

src/context/signal.rs

@@ -17,7 +17,7 @@ pub extern "C" fn signal_handler(sig: usize) {
         let contexts = contexts();
         let context_lock = contexts.current().expect("context::signal_handler not inside of context");
         let context = context_lock.read();
-        let actions = context.actions.lock();
+        let actions = context.actions.read();
         actions[sig]
     };
 

src/ptrace.rs

@@ -404,7 +404,7 @@ pub unsafe fn regs_for(context: &Context) -> Option<&InterruptStack> {
         None => None,
         Some((_, _, ref kstack, signum)) => {
             let is_user_handled = {
-                let actions = context.actions.lock();
+                let actions = context.actions.read();
                 signal::is_user_handled(actions[signum as usize].0.sa_handler)
             };
             if is_user_handled {
@@ -425,7 +425,7 @@ pub unsafe fn regs_for_mut(context: &mut Context) -> Option<&mut InterruptStack>
         None => None,
         Some((_, _, ref mut kstack, signum)) => {
             let is_user_handled = {
-                let actions = context.actions.lock();
+                let actions = context.actions.read();
                 signal::is_user_handled(actions[signum as usize].0.sa_handler)
             };
             if is_user_handled {

src/syscall/process.rs

@@ -265,7 +265,7 @@ pub fn clone(flags: CloneFlags, stack_base: usize) -> Result<ContextId> {
             if flags.contains(CLONE_SIGHAND) {
                 actions = Arc::clone(&context.actions);
             } else {
-                actions = Arc::new(Mutex::new(context.actions.lock().clone()));
+                actions = Arc::new(RwLock::new(context.actions.read().clone()));
             }
         }
 
@@ -849,7 +849,7 @@ fn fexec_noreturn(
             drop(args);
             drop(vars);
 
-            context.actions = Arc::new(Mutex::new(vec![(
+            context.actions = Arc::new(RwLock::new(vec![(
                 SigAction {
                     sa_handler: unsafe { mem::transmute(SIG_DFL) },
                     sa_mask: [0; 2],
@@ -1414,7 +1414,7 @@ pub fn sigaction(sig: usize, act_opt: Option<&SigAction>, oldact_opt: Option<&mu
         let contexts = context::contexts();
         let context_lock = contexts.current().ok_or(Error::new(ESRCH))?;
         let context = context_lock.read();
-        let mut actions = context.actions.lock();
+        let mut actions = context.actions.write();
 
         if let Some(oldact) = oldact_opt {
             *oldact = actions[sig].0;