Changeset 635 for trunk/kernel/libk/xhtab.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/xhtab.c (modified) (6 diffs)

trunk/kernel/libk/xhtab.c

@@ -2 +2 @@
  * xhtab.c - Remote access embedded hash table implementation.
  * 
- * Author     Alain Greiner          (2016,2017)
+ * Author     Alain Greiner   (2016,2017,2018,2019)
  *
  * Copyright (c) UPMC Sorbonne Universites
@@ -134 +134 @@
         uint32_t i;
 
-    // initialize readlock
+    // initialize lock
     remote_busylock_init( XPTR( local_cxy , &xhtab->lock), LOCK_XHTAB_STATE );
 
@@ -153 +153 @@
     }
 
-        for( i=0 ; i < XHASHTAB_SIZE ; i++ )
-    {
-                xlist_root_init( XPTR( local_cxy , &xhtab->roots[i] ) );
-    }  
-
-#if DEBUG_XHTAB
-printk("\n@@@ %s for xhtab (%x,%x)\n"
+#if DEBUG_XHTAB
+printk("\n[%s] for xhtab (%x,%x)\n"
 " - index_from_key  = %x (@ %x)\n"
 " - item_match_key  = %x (@ %x)\n"
@@ -169 +164 @@
 #endif
 
+        for( i=0 ; i < XHASHTAB_SIZE ; i++ )
+    {
+                xlist_root_init( XPTR( local_cxy , &xhtab->roots[i] ) );
+
+#if (DEBUG_XHTAB & 1)
+printk("\n - initialize root[%d] / %x\n", i , &xhtab->roots[i] ); 
+#endif
+
+    }  
+
 }  // end xhtab_init()
 
-//////////////////////////////////////
-xptr_t xhtab_scan( xptr_t    xhtab_xp,
-                   uint32_t  index,
-                   void    * key )
+/////////////////////////////////////////////////////////////////////////////////////////////
+// This static function traverse the subset identified by the <index> argument
+// to find an item identified by the <key> argument.
+/////////////////////////////////////////////////////////////////////////////////////////////
+// @ xhtab_xp  : extended pointer on the xhtab descriptor.
+// @ index     : subset index.
+// @ key       : searched key value.
+// @ return  extended pointer on the found item if success / return XPTR_NULL if not found.
+/////////////////////////////////////////////////////////////////////////////////////////////
+static xptr_t xhtab_scan( xptr_t    xhtab_xp,
+                          uint32_t  index,
+                          void    * key )
 {
     xptr_t              xlist_xp;           // xlist_entry_t (iterator)
@@ -220 +233 @@
     index_from_key_t * index_from_key;     // function pointer
     
-#if DEBUG_XHTAB
-printk("\n[%s] enter / key %s\n", __FUNCTION__, key );
-#endif
-
-    // get xhtab cluster and local pointer 
-    xhtab_cxy = GET_CXY( xhtab_xp );
-    xhtab_ptr = GET_PTR( xhtab_xp );
+    // get xhtab cluster and local pointer 
+    xhtab_cxy = GET_CXY( xhtab_xp );
+    xhtab_ptr = GET_PTR( xhtab_xp );
+
+#if DEBUG_XHTAB
+printk("\n[%s] enter / xhtab (%x,%x) / key = <%s> / cycle %d\n",
+__FUNCTION__, xhtab_cxy, xhtab_ptr, key, (uint32_t)hal_get_cycles() );
+#endif
+
+    // build extended pointer on xhtab lock
+    xptr_t lock_xp = XPTR( xhtab_cxy , &xhtab_ptr->lock );
 
     // get pointer on "index_from_key" function
     index_from_key = (index_from_key_t *)hal_remote_lpt( XPTR( xhtab_cxy , 
                                                          &xhtab_ptr->index_from_key ) );
+#if DEBUG_XHTAB
+printk("\n[%s] remote = %x / direct = %x / @ = %x\n",
+__FUNCTION__, index_from_key, xhtab_ptr->index_from_key, &xhtab_ptr->index_from_key );
+#endif
+
     // compute index from key
         index = index_from_key( key );
 
+#if DEBUG_XHTAB
+printk("\n[%s] index = %x\n", __FUNCTION__, index );
+#endif
+
     // take the lock protecting hash table
-    remote_busylock_acquire( XPTR( xhtab_cxy , &xhtab_ptr->lock ) );
-
-    // search a matching item 
+    remote_busylock_acquire( lock_xp );
+
+    // search a matching item in subset
     item_xp = xhtab_scan( xhtab_xp , index , key );
 
-    if( item_xp != XPTR_NULL )    // error if found
+    if( item_xp != XPTR_NULL )    // error if item already registered
     {
         // release the lock protecting hash table
-        remote_busylock_release( XPTR( xhtab_cxy , &xhtab_ptr->lock ) );
+        remote_busylock_release( lock_xp );
 
         return -1;
@@ -256 +282 @@
 
         // release the lock protecting hash table
-        remote_busylock_release( XPTR( xhtab_cxy , &xhtab_ptr->lock ) );
+        remote_busylock_release( lock_xp );
     
 #if DEBUG_XHTAB
-printk("\n[%s] success / %s\n", __FUNCTION__, key );
+printk("\n[%s] success / <%s>\n", __FUNCTION__, key );
 #endif