Changeset a33c113 for libcfa/src/concurrency

Timestamp:

Apr 14, 2021, 3:41:06 PM (3 years ago)

Author:

Thierry Delisle <tdelisle@…>

Branches:

ADT, arm-eh, ast-experimental, enum, forall-pointer-decay, jacob/cs343-translation, master, new-ast-unique-expr, pthread-emulation, qualifiedEnum

Children:

a7504db

Parents:

634a5c2

Message:

Minor changes so using the global RWlock is more concise.

Location:

libcfa/src/concurrency

Files:

• kernel/startup.cfa (modified) (2 diffs)
• kernel_private.hfa (modified) (3 diffs)
• preemption.cfa (modified) (2 diffs)
• ready_queue.cfa (modified) (3 diffs)

libcfa/src/concurrency/kernel/startup.cfa

@@ -493 +493 @@
         unlock( this.cltr->idles );
 
-        id = doregister((__processor_id_t*)&this);
-
-        // Lock the RWlock so no-one pushes/pops while we are changing the queue
-        uint_fast32_t last_size = ready_mutate_lock();
+        // Register and Lock the RWlock so no-one pushes/pops while we are changing the queue
+        uint_fast32_t last_size = ready_mutate_register((__processor_id_t*)&this);
 
                 // Adjust the ready queue size
@@ -519 +517 @@
                 ready_queue_shrink( this.cltr, target );
 
-        // Unlock the RWlock
-        ready_mutate_unlock( last_size );
-
-        // Finally we don't need the read_lock any more
-        unregister((__processor_id_t*)&this);
+        // Unlock the RWlock and unregister: we don't need the read_lock any more
+        ready_mutate_unregister((__processor_id_t*)&this, last_size );
 
         close(this.idle);

libcfa/src/concurrency/kernel_private.hfa

@@ -83 +83 @@
 // Cluster lock API
 //=======================================================================
-// Cells use by the reader writer lock
-// while not generic it only relies on a opaque pointer
-struct __attribute__((aligned(128))) __scheduler_lock_id_t {
-        // Spin lock used as the underlying lock
-        volatile bool lock;
-
-        // Handle pointing to the proc owning this cell
-        // Used for allocating cells and debugging
-        __processor_id_t * volatile handle;
-
-        #ifdef __CFA_WITH_VERIFY__
-                // Debug, check if this is owned for reading
-                bool owned;
-        #endif
-};
-
-static_assert( sizeof(struct __scheduler_lock_id_t) <= __alignof(struct __scheduler_lock_id_t));
-
 // Lock-Free registering/unregistering of threads
 // Register a processor to a given cluster and get its unique id in return
-unsigned doregister( struct __processor_id_t * proc );
+void register_proc_id( struct __processor_id_t * );
 
 // Unregister a processor from a given cluster using its id, getting back the original pointer
-void     unregister( struct __processor_id_t * proc );
+void unregister_proc_id( struct __processor_id_t * proc );
 
 //-----------------------------------------------------------------------
@@ -153 +135 @@
 }
 
+// Cells use by the reader writer lock
+// while not generic it only relies on a opaque pointer
+struct __attribute__((aligned(128))) __scheduler_lock_id_t {
+        // Spin lock used as the underlying lock
+        volatile bool lock;
+
+        // Handle pointing to the proc owning this cell
+        // Used for allocating cells and debugging
+        __processor_id_t * volatile handle;
+
+        #ifdef __CFA_WITH_VERIFY__
+                // Debug, check if this is owned for reading
+                bool owned;
+        #endif
+};
+
+static_assert( sizeof(struct __scheduler_lock_id_t) <= __alignof(struct __scheduler_lock_id_t));
+
 //-----------------------------------------------------------------------
 // Reader-Writer lock protecting the ready-queues
@@ -247 +247 @@
 void ready_mutate_unlock( uint_fast32_t /* value returned by lock */ );
 
+//-----------------------------------------------------------------------
+// Lock-Free registering/unregistering of threads
+// Register a processor to a given cluster and get its unique id in return
+// For convenience, also acquires the lock
+static inline uint_fast32_t ready_mutate_register( struct __processor_id_t * proc ) {
+        register_proc_id( proc );
+        return ready_mutate_lock();
+}
+
+// Unregister a processor from a given cluster using its id, getting back the original pointer
+// assumes the lock is acquired
+static inline void ready_mutate_unregister( struct __processor_id_t * proc, uint_fast32_t last_s ) {
+        ready_mutate_unlock( last_s );
+        unregister_proc_id( proc );
+}
+
 //=======================================================================
 // Ready-Queue API

libcfa/src/concurrency/preemption.cfa

@@ -712 +712 @@
 static void * alarm_loop( __attribute__((unused)) void * args ) {
         __processor_id_t id;
-        id.id = doregister(&id);
+        register_proc_id(&id);
         __cfaabi_tls.this_proc_id = &id;
 
@@ -773 +773 @@
 EXIT:
         __cfaabi_dbg_print_safe( "Kernel : Preemption thread stopping\n" );
-        unregister(&id);
+        register_proc_id(&id);
 
         return 0p;

libcfa/src/concurrency/ready_queue.cfa

@@ -94 +94 @@
 //=======================================================================
 // Lock-Free registering/unregistering of threads
-unsigned doregister( struct __processor_id_t * proc ) with(*__scheduler_lock) {
+void register_proc_id( struct __processor_id_t * proc ) with(*__scheduler_lock) {
         __cfadbg_print_safe(ready_queue, "Kernel : Registering proc %p for RW-Lock\n", proc);
 
@@ -108 +108 @@
                         /*paranoid*/ verify(0 == (__alignof__(data[i]) % cache_line_size));
                         /*paranoid*/ verify((((uintptr_t)&data[i]) % cache_line_size) == 0);
-                        return i;
+                        proc->id = i;
                 }
         }
@@ -135 +135 @@
         /*paranoid*/ verify(__alignof__(data[n]) == (2 * cache_line_size));
         /*paranoid*/ verify((((uintptr_t)&data[n]) % cache_line_size) == 0);
-        return n;
-}
-
-void unregister( struct __processor_id_t * proc ) with(*__scheduler_lock) {
+        proc->id = n;
+}
+
+void unregister_proc_id( struct __processor_id_t * proc ) with(*__scheduler_lock) {
         unsigned id = proc->id;
         /*paranoid*/ verify(id < ready);