Changeset 7c98874 in mainline

Timestamp:

2009-01-31T12:37:31Z (15 years ago)

Author:

Martin Decky <martin@…>

Branches:

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

Children:

896ad9f

Parents:

ee79df74

Message:

use secondary hash for kernel identity mapping to avoid livelocks on colliding PHT addresses

File:

• kernel/arch/ppc32/src/mm/tlb.c (modified) (6 diffs)

kernel/arch/ppc32/src/mm/tlb.c

@@ -152 +152 @@
         bool found = false;
         
-        /* Find unused or colliding
-           PTE in PTEG */
+        /* Find unused or colliding PTE in PTEG */
         for (i = 0; i < 8; i++) {
-                if ((!phte[base + i].v) || ((phte[base + i].vsid == vsid) &&
-                    (phte[base + i].api == api))) {
+                if ((!phte[base + i].v) ||
+                    ((phte[base + i].vsid == vsid)
+                    && (phte[base + i].api == api)
+                    && (phte[base + i].h == 0))) {
                         found = true;
                         break;
@@ -166 +167 @@
                 uint32_t base2 = (~hash & 0x3ff) << 3;
                 
-                /* Find unused or colliding
-                   PTE in PTEG */
+                /* Find unused or colliding PTE in PTEG */
                 for (i = 0; i < 8; i++) {
                         if ((!phte[base2 + i].v) ||
-                            ((phte[base2 + i].vsid == vsid) &&
-                            (phte[base2 + i].api == api))) {
+                            ((phte[base2 + i].vsid == vsid)
+                            && (phte[base2 + i].api == api)
+                            && (phte[base2 + i].h == 1))) {
                                 found = true;
                                 base = base2;
@@ -179 +180 @@
                 }
                 
-                if (!found) {
-                        // TODO: A/C precedence groups
+                if (!found)
                         i = page % 8;
-                }
-        }
+        }
+        
+        
         
         phte[base + i].v = 1;
@@ -223 +224 @@
         bool found = false;
         
-        /* Find unused or colliding
-           PTE in PTEG */
+        /* Find unused or colliding PTE in PTEG */
         for (i = 0; i < 8; i++) {
                 if ((!phte_physical[base + i].v) ||
-                    ((phte_physical[base + i].vsid == vsid) &&
-                    (phte_physical[base + i].api == api))) {
+                    ((phte_physical[base + i].vsid == vsid)
+                    && (phte_physical[base + i].api == api)
+                    && (phte_physical[base + i].h == 0))) {
                         found = true;
                         break;
@@ -238 +239 @@
                 uint32_t base2 = (~hash & 0x3ff) << 3;
                 
-                /* Find unused or colliding
-                   PTE in PTEG */
+                /* Find unused or colliding PTE in PTEG */
                 for (i = 0; i < 8; i++) {
                         if ((!phte_physical[base2 + i].v) ||
-                            ((phte_physical[base2 + i].vsid == vsid) &&
-                            (phte_physical[base2 + i].api == api))) {
+                            ((phte_physical[base2 + i].vsid == vsid)
+                            && (phte_physical[base2 + i].api == api)
+                            && (phte_physical[base2 + i].h == 1))) {
                                 found = true;
                                 base = base2;
@@ -252 +253 @@
                 
                 if (!found) {
-                        // TODO: A/C precedence groups
                         i = page % 8;
+                        base = base2;
+                        h = 1;
                 }
         }