Changeset 879585a3 in mainline for kernel/genarch/src/mm/asid.c

Timestamp:

2007-03-31T22:22:50Z (18 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

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

Children:

31d8e10

Parents:

563c2dd

Message:

Simplify synchronization in as_switch().
The function was oversynchronized, which
was causing deadlocks on the address
space mutex.

Now, address spaces can only be switched
when the asidlock is held. This also protects
stealing of ASIDs. No other synchronization
is necessary.

File:

• kernel/genarch/src/mm/asid.c (modified) (6 diffs)

kernel/genarch/src/mm/asid.c

@@ -63 +63 @@
 #include <synch/spinlock.h>
 #include <synch/mutex.h>
-#include <arch.h>
 #include <adt/list.h>
 #include <debug.h>
-
-/**
- * asidlock protects the asids_allocated counter.
- */
-SPINLOCK_INITIALIZE(asidlock);
 
 static count_t asids_allocated = 0;
@@ -91 +85 @@
          */
         
-        spinlock_lock(&asidlock);
         if (asids_allocated == ASIDS_ALLOCABLE) {
 
@@ -109 +102 @@
                 
                 as = list_get_instance(tmp, as_t, inactive_as_with_asid_link);
-                mutex_lock_active(&as->lock);
 
                 /*
@@ -131 +123 @@
                 as_invalidate_translation_cache(as, 0, (count_t) -1);
                 
-                mutex_unlock(&as->lock);
-
                 /*
                  * Get the system rid of the stolen ASID.
@@ -157 +147 @@
         }
         
-        spinlock_unlock(&asidlock);
-        
         return asid;
 }
@@ -171 +159 @@
 void asid_put(asid_t asid)
 {
-        ipl_t ipl;
-
-        ipl = interrupts_disable();
-        spinlock_lock(&asidlock);
-
         asids_allocated--;
         asid_put_arch(asid);
-        
-        spinlock_unlock(&asidlock);
-        interrupts_restore(ipl);
 }