Changeset 31d8e10 in mainline for kernel/generic/include/mm/as.h

Timestamp:

2007-04-05T16:09:49Z (18 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

547fa39

Parents:

879585a3

Message:

Continue to de-oversynchronize the kernel.

• replace as→refcount with an atomic counter; accesses to this

reference counter are not to be done when the as→lock mutex is held;
this gets us rid of mutex_lock_active();

Remove the possibility of a deadlock between TLB shootdown and asidlock.

• get rid of mutex_lock_active() on as→lock
• when locking the asidlock spinlock, always do it conditionally and with

preemption disabled; in the unsuccessful case, enable interrupts and try again

• there should be no deadlock between TLB shootdown and the as→lock mutexes
• PLEASE REVIEW !!!

Add DEADLOCK_PROBE's to places where we have spinlock_trylock() loops.

File:

• kernel/generic/include/mm/as.h (modified) (2 diffs)

kernel/generic/include/mm/as.h

@@ -102 +102 @@
                 asid_t asid;
                 
+                /** Number of references (i.e tasks that reference this as). */
+                atomic_t refcount;
+
                 mutex_t lock;
-                
-                /** Number of references (i.e tasks that reference this as). */
-                count_t refcount;
                 
                 /** B+tree of address space areas. */
@@ -148 +148 @@
         asid_t asid;
 
+        /** Number of references (i.e tasks that reference this as). */
+        atomic_t refcount;
+
         mutex_t lock;
-
-        /** Number of references (i.e tasks that reference this as). */
-        count_t refcount;
 
         /** B+tree of address space areas. */