Changeset 635 for trunk/kernel/libk/remote_mutex.c

Timestamp:

Jun 26, 2019, 11:42:37 AM (5 years ago)

Author:

alain

Message:

This version is a major evolution: The physical memory allocators,
defined in the kmem.c, ppm.c, and kcm.c files have been modified
to support remote accesses. The RPCs that were previously user
to allocate physical memory in a remote cluster have been removed.
This has been done to cure a dead-lock in case of concurrent page-faults.

This version 2.2 has been tested on a (4 clusters / 2 cores per cluster)
TSAR architecture, for both the "sort" and the "fft" applications.

File:

• trunk/kernel/libk/remote_mutex.c (modified) (5 diffs)

trunk/kernel/libk/remote_mutex.c

@@ -2 +2 @@
  * remote_mutex.c - POSIX mutex implementation.
  * 
- * Authors   Alain   Greiner (2016,2017,2018)
+ * Authors   Alain   Greiner (2016,2017,2018,2019)
  *
  * Copyright (c) UPMC Sorbonne Universites
@@ -84 +84 @@
 error_t remote_mutex_create( intptr_t ident )
 { 
-    xptr_t           mutex_xp;
     remote_mutex_t * mutex_ptr;
+    kmem_req_t       req;   
 
     // get pointer on local process descriptor
@@ -97 +97 @@
     process_t * ref_ptr = (process_t *)GET_PTR( ref_xp );
 
-    // allocate memory for mutex descriptor
-    if( ref_cxy == local_cxy )                  // local cluster is the reference 
-    {
-        kmem_req_t req;   
-        req.type    = KMEM_MUTEX;
-        req.flags   = AF_ZERO;
-        mutex_ptr   = kmem_alloc( &req );
-        mutex_xp    = XPTR( local_cxy , mutex_ptr );
-    }
-    else                                       // reference is remote
-    {
-        rpc_kcm_alloc_client( ref_cxy , KMEM_MUTEX , &mutex_xp );
-        mutex_ptr = GET_PTR( mutex_xp );
-    }
-
-    if( mutex_ptr == NULL ) return 0xFFFFFFFF;
+    // allocate memory for mutex descriptor in reference cluster
+    req.type    = KMEM_KCM;
+    req.order   = bits_log2( sizeof(remote_mutex_t) );
+    req.flags   = AF_ZERO | AF_KERNEL;
+    mutex_ptr   = kmem_remote_alloc( ref_cxy , &req );
+
+    if( mutex_ptr == NULL )
+    {
+       printk("\n[ERROR] in %s : cannot create mutex\n", __FUNCTION__);
+       return -1;
+    }
 
     // initialise mutex
@@ -150 +145 @@
 void remote_mutex_destroy( xptr_t mutex_xp )
 {
+    kmem_req_t  req;
+
     // get pointer on local process descriptor
     process_t * process = CURRENT_THREAD->process;
@@ -174 +171 @@
 
     // release memory allocated for mutex descriptor
-    if( mutex_cxy == local_cxy )                            // reference is local
-    {
-        kmem_req_t  req;
-        req.type = KMEM_MUTEX;
-        req.ptr  = mutex_ptr;
-        kmem_free( &req );
-    }
-    else                                                  // reference is remote
-    {
-        rpc_kcm_free_client( mutex_cxy , mutex_ptr , KMEM_MUTEX );
-    }
+    req.type = KMEM_KCM;
+    req.ptr  = mutex_ptr;
+    kmem_remote_free( mutex_cxy , &req );
 
 }  // end remote_mutex_destroy()