Changeset 657 for trunk/kernel/kern/chdev.c

Timestamp:

Mar 18, 2020, 11:16:59 PM (5 years ago)

Author:

alain

Message:

Introduce remote_buf.c/.h & socket.c/.h files.
Update dev_nic.c/.h files.

File:

• trunk/kernel/kern/chdev.c (modified) (8 diffs)

trunk/kernel/kern/chdev.c

@@ -1 +1 @@
 /*
- * chdev.c - channel device descriptor operations implementation.
+ * chdev.c - channel device API implementation.
  *
- * Authors  Alain Greiner   (2016)
+ * Authors  Alain Greiner   (2016,2017,2018,2019,2020)
  *
  * Copyright (c) UPMC Sorbonne Universites
@@ -148 +148 @@
 #endif
 
-    thread_t * this = CURRENT_THREAD;
+    thread_t * this      = CURRENT_THREAD;
+    xptr_t     client_xp = XPTR( local_cxy , this );
 
     // get chdev cluster and local pointer
@@ -197 +198 @@
     lock_xp            = XPTR( chdev_cxy , &chdev_ptr->wait_lock );
 
-    // The following actions execute in critical section,
-    // because the lock_acquire / lock_release : 
-    // (1) take the lock protecting the chdev state
+    // The following actions are executed in critical section,
+    // (because the busylock_acquire / busylock_release) 
+    // (1) take the lock protecting the waiting queue
     // (2) register client thread in server queue 
     // (3) unblock the server thread and block client thread
@@ -224 +225 @@
  
     // 3. client thread unblocks server thread and blocks itself
-    thread_unblock( server_xp , THREAD_BLOCKED_IDLE );
-    thread_block( XPTR( local_cxy , CURRENT_THREAD ) , THREAD_BLOCKED_IO );
+    thread_unblock( server_xp , THREAD_BLOCKED_CLIENT );
+    thread_block( client_xp , THREAD_BLOCKED_IO );
 
 #if (DEBUG_CHDEV_CMD_TX & 1)
@@ -300 +301 @@
     server = CURRENT_THREAD;
 
-    // build extended pointer on root of client threads queue
+    // build extended pointer on root & lock of client threads queue
     root_xp = XPTR( local_cxy , &chdev->wait_root );
-
-    // build extended pointer on lock protecting client threads queue
     lock_xp = XPTR( local_cxy , &chdev->wait_lock );
 
@@ -351 +350 @@
 #endif
             // block 
-            thread_block( XPTR( local_cxy , server ) , THREAD_BLOCKED_IDLE ); 
+            thread_block( XPTR( local_cxy , server ) , THREAD_BLOCKED_CLIENT ); 
 
             // deschedule
@@ -358 +357 @@
         else                            // waiting queue not empty
         {
+            // get pointers on first client thread
+            client_xp  = XLIST_FIRST( root_xp , thread_t , wait_list );
+            client_cxy = GET_CXY( client_xp );
+            client_ptr = GET_PTR( client_xp );
+
+            // remove this client thread from chdev waiting queue
+            xlist_unlink( XPTR( client_cxy , &client_ptr->wait_list ) );
+
             // release lock protecting the waiting queue
             remote_busylock_release( lock_xp );
-
-            // get extended pointer on first client thread
-            client_xp = XLIST_FIRST( root_xp , thread_t , wait_list );
-
-            // get client thread cluster and local pointer
-            client_cxy = GET_CXY( client_xp );
-            client_ptr = GET_PTR( client_xp );
 
 #if( DEBUG_CHDEV_SERVER_TX || DEBUG_CHDEV_SERVER_RX )
@@ -402 +402 @@
             // unblock client thread when driver returns
             thread_unblock( client_xp , THREAD_BLOCKED_IO );
-
-            // get the lock protecting the waiting queue
-            remote_busylock_acquire( lock_xp );
-
-            // remove this client thread from chdev waiting queue
-            xlist_unlink( XPTR( client_cxy , &client_ptr->wait_list ) );
-
-            // release lock protecting the waiting queue
-            remote_busylock_release( lock_xp );
 
 #if DEBUG_CHDEV_SERVER_RX