Changeset 03427d0 in mainline for arch/ia64/src/proc/scheduler.c

Timestamp:

2006-03-02T17:57:45Z (19 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

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

Children:

9459255

Parents:

9ad03fe

Message:

ia64 work.
Add code needed for running multiple address spaces and location of kernel stack
after switch from userspace.

File:

• arch/ia64/src/proc/scheduler.c (modified) (2 diffs)

arch/ia64/src/proc/scheduler.c

@@ -34 +34 @@
 #include <align.h>
 
-/** Ensure that thread's kernel stack is locked in TLB. */
+/** Record kernel stack address in ar.k7 and make sure it is mapped in DTR. */
 void before_thread_runs_arch(void)
 {
@@ -43 +43 @@
         if ((__address) THREAD->kstack < base || (__address) THREAD->kstack > base + (1<<KERNEL_PAGE_WIDTH)) {
                 /*
-                 * Kernel stack of this thread is not locked in DTLB.
-                 * First, make sure it is not mapped already.
-                 * If not, fill respective tranlsation register.
+                 * Kernel stack of this thread is not mapped by DTR[TR_KERNEL].
+                 * Use DTR[TR_KSTACK] to map it.
                  */
                  dtlb_kernel_mapping_insert((__address) THREAD->kstack, KA2PA(THREAD->kstack), true, DTR_KSTACK);
         }
+        
+        /*
+         * Record address of kernel stack to ar.k7
+         * where it will be found after switch
+         * from userspace.
+         */
+        __asm__ volatile ("mov ar.k7 = %0\n" : : "r" (THREAD->kstack));
 }