Bug fixes in the TLB

Make our replacement algorithm same as legion (although not same as the spec)
itb should be 64 entries not 48

src/arch/sparc/tlb.cc:
    Bug fixes in the TLB
    Make our replacement algorithm same as legion (although not same as the spec)
src/arch/sparc/tlb.hh:
    Make our replacement algorithm same as legion (although not same as the spec)
src/python/m5/objects/SparcTLB.py:
    itb should be 64 entries too

--HG--
extra : convert_revision : 1b5cb3597091e3cfe293e94f6f2219b1e621c35f

src/arch/sparc/tlb.cc

@@ -45,7 +45,8 @@ namespace SparcISA
 {
 
 TLB::TLB(const std::string &name, int s)
-    : SimObject(name), size(s), usedEntries(0), cacheValid(false)
+    : SimObject(name), size(s), usedEntries(0), lastReplaced(0),
+      cacheValid(false)
 {
     // To make this work you'll have to change the hypervisor and OS
     if (size > 64)
@@ -53,13 +54,16 @@ TLB::TLB(const std::string &name, int s)
 
     tlb = new TlbEntry[size];
     memset(tlb, 0, sizeof(TlbEntry) * size);
+
+    for (int x = 0; x < size; x++)
+        freeList.push_back(&tlb[x]);
 }
 
 void
 TLB::clearUsedBits()
 {
     MapIter i;
-    for (i = lookupTable.begin(); i != lookupTable.end();) {
+    for (i = lookupTable.begin(); i != lookupTable.end(); i++) {
         TlbEntry *t = i->second;
         if (!t->pte.locked()) {
             t->used = false;
@@ -77,32 +81,76 @@ TLB::insert(Addr va, int partition_id, int context_id, bool real,
 
     MapIter i;
     TlbEntry *new_entry = NULL;
+    TlbRange tr;
     int x;
 
     cacheValid = false;
+    tr.va = va;
+    tr.size = PTE.size() - 1;
+    tr.contextId = context_id;
+    tr.partitionId = partition_id;
+    tr.real = real;
+
+
+    DPRINTF(TLB, "TLB: Inserting TLB Entry; va=%#x pa=%#x pid=%d cid=%d r=%d entryid=%d\n",
+            va, PTE.paddr(), partition_id, context_id, (int)real, entry);
+
+    // Demap any entry that conflicts
+    i = lookupTable.find(tr);
+    if (i != lookupTable.end()) {
+        i->second->valid = false;
+        if (i->second->used) {
+            i->second->used = false;
+            usedEntries--;
+        }
+        freeList.push_front(i->second);
+        DPRINTF(TLB, "TLB: Found conflicting entry %#X , deleting it\n",
+                i->second);
+        lookupTable.erase(i);
+    }
 
-    DPRINTF(TLB, "TLB: Inserting TLB Entry; va=%#x pa=%#x pid=%d cid=%d r=%d\n",
-            va, PTE.paddr(), partition_id, context_id, (int)real);
 
     if (entry != -1) {
         assert(entry < size && entry >= 0);
         new_entry = &tlb[entry];
     } else {
+        if (!freeList.empty()) {
+            new_entry = freeList.front();
+        } else {
+            x = lastReplaced;
+            do {
+                ++x;
+                if (x == size)
+                    x = 0;
+                if (x == lastReplaced)
+                    goto insertAllLocked;
+            } while (tlb[x].pte.locked());
+            lastReplaced = x;
+            new_entry = &tlb[x];
+            lookupTable.erase(new_entry->range);
+        }
+        /*
         for (x = 0; x < size; x++) {
             if (!tlb[x].valid || !tlb[x].used)  {
                 new_entry = &tlb[x];
                 break;
             }
-        }
+        }*/
     }
 
+insertAllLocked:
     // Update the last ently if their all locked
-    if (!new_entry)
+    if (!new_entry) {
         new_entry = &tlb[size-1];
+        lookupTable.erase(new_entry->range);
+    }
+
+    freeList.remove(new_entry);
+    DPRINTF(TLB, "Using entry: %#X\n", new_entry);
 
     assert(PTE.valid());
     new_entry->range.va = va;
-    new_entry->range.size = PTE.size();
+    new_entry->range.size = PTE.size() - 1;
     new_entry->range.partitionId = partition_id;
     new_entry->range.contextId = context_id;
     new_entry->range.real = real;
@@ -112,17 +160,6 @@ TLB::insert(Addr va, int partition_id, int context_id, bool real,
     usedEntries++;
 
 
-    // Demap any entry that conflicts
-    i = lookupTable.find(new_entry->range);
-    if (i != lookupTable.end()) {
-        i->second->valid = false;
-        if (i->second->used) {
-            i->second->used = false;
-            usedEntries--;
-        }
-        DPRINTF(TLB, "TLB: Found conflicting entry, deleting it\n");
-        lookupTable.erase(i);
-    }
 
     i = lookupTable.insert(new_entry->range, new_entry);
     assert(i != lookupTable.end());
@@ -219,6 +256,8 @@ TLB::demapPage(Addr va, int partition_id, bool real, int context_id)
             i->second->used = false;
             usedEntries--;
         }
+        freeList.push_front(i->second);
+        DPRINTF(TLB, "Freeing TLB entry : %#X\n", i->second);
         lookupTable.erase(i);
     }
 }
@@ -233,6 +272,10 @@ TLB::demapContext(int partition_id, int context_id)
     for (x = 0; x < size; x++) {
         if (tlb[x].range.contextId == context_id &&
             tlb[x].range.partitionId == partition_id) {
+            if (tlb[x].valid == true) {
+                freeList.push_front(&tlb[x]);
+                DPRINTF(TLB, "Freeing TLB entry : %#X\n", &tlb[x]);
+            }
             tlb[x].valid = false;
             if (tlb[x].used) {
                 tlb[x].used = false;
@@ -251,6 +294,10 @@ TLB::demapAll(int partition_id)
     cacheValid = false;
     for (x = 0; x < size; x++) {
         if (!tlb[x].pte.locked() && tlb[x].range.partitionId == partition_id) {
+            if (tlb[x].valid == true){
+                freeList.push_front(&tlb[x]);
+                DPRINTF(TLB, "Freeing TLB entry : %#X\n", &tlb[x]);
+            }
             tlb[x].valid = false;
             if (tlb[x].used) {
                 tlb[x].used = false;
@@ -267,7 +314,10 @@ TLB::invalidateAll()
     int x;
     cacheValid = false;
 
+    freeList.clear();
     for (x = 0; x < size; x++) {
+        if (tlb[x].valid == true)
+            freeList.push_back(&tlb[x]);
         tlb[x].valid = false;
     }
     usedEntries = 0;
@@ -275,17 +325,26 @@ TLB::invalidateAll()
 
 uint64_t
 TLB::TteRead(int entry) {
+    if (entry >= size)
+        panic("entry: %d\n", entry);
+
     assert(entry < size);
+    if (tlb[entry].valid)
         return tlb[entry].pte();
+    else
+        return (uint64_t)-1ll;
 }
 
 uint64_t
 TLB::TagRead(int entry) {
     assert(entry < size);
     uint64_t tag;
+    if (!tlb[entry].valid)
+        return (uint64_t)-1ll;
 
-    tag = tlb[entry].range.contextId | tlb[entry].range.va |
+    tag = tlb[entry].range.contextId;
-          (uint64_t)tlb[entry].range.partitionId << 61;
+    tag |= tlb[entry].range.va;
+    tag |= (uint64_t)tlb[entry].range.partitionId << 61;
     tag |= tlb[entry].range.real ? ULL(1) << 60 : 0;
     tag |= (uint64_t)~tlb[entry].pte._size() << 56;
     return tag;
@@ -501,13 +560,13 @@ DTB::translate(RequestPtr &req, ThreadContext *tc, bool write)
     // Be fast if we can!
     if (cacheValid &&  cacheState == tlbdata) {
         if (cacheEntry[0] && cacheAsi[0] == asi && cacheEntry[0]->range.va < vaddr + size &&
-            cacheEntry[0]->range.va + cacheEntry[0]->range.size >= vaddr) {
+            cacheEntry[0]->range.va + cacheEntry[0]->range.size > vaddr) {
                 req->setPaddr(cacheEntry[0]->pte.paddr() & ~(cacheEntry[0]->pte.size()-1) |
                               vaddr & cacheEntry[0]->pte.size()-1 );
                 return NoFault;
         }
         if (cacheEntry[1] && cacheAsi[1] == asi && cacheEntry[1]->range.va < vaddr + size &&
-            cacheEntry[1]->range.va + cacheEntry[1]->range.size >= vaddr) {
+            cacheEntry[1]->range.va + cacheEntry[1]->range.size > vaddr) {
                 req->setPaddr(cacheEntry[1]->pte.paddr() & ~(cacheEntry[1]->pte.size()-1) |
                               vaddr & cacheEntry[1]->pte.size()-1 );
                 return NoFault;
@@ -667,8 +726,12 @@ continueDtbFlow:
     }
 
     // cache translation date for next translation
-    cacheValid = true;
     cacheState = tlbdata;
+    if (!cacheValid) {
+        cacheEntry[1] = NULL;
+        cacheEntry[0] = NULL;
+    }
+
     if (cacheEntry[0] != e && cacheEntry[1] != e) {
         cacheEntry[1] = cacheEntry[0];
         cacheEntry[0] = e;
@@ -677,7 +740,7 @@ continueDtbFlow:
         if (implicit)
             cacheAsi[0] = (ASI)0;
     }
-
+    cacheValid = true;
     req->setPaddr(e->pte.paddr() & ~(e->pte.size()-1) |
                   vaddr & e->pte.size()-1);
     DPRINTF(TLB, "TLB: %#X -> %#X\n", vaddr, req->getPaddr());
@@ -696,7 +759,7 @@ handleQueueRegAccess:
         writeSfr(tc, vaddr, write, Primary, true, IllegalAsi, asi);
         return new PrivilegedAction;
     }
-    if (priv && vaddr & 0xF || vaddr > 0x3f8 || vaddr < 0x3c0) {
+    if (!hpriv && vaddr & 0xF || vaddr > 0x3f8 || vaddr < 0x3c0) {
         writeSfr(tc, vaddr, write, Primary, true, IllegalAsi, asi);
         return new DataAccessException;
     }

src/arch/sparc/tlb.hh

@@ -54,10 +54,13 @@ class TLB : public SimObject
 
     int size;
     int usedEntries;
+    int lastReplaced;
 
     uint64_t cacheState;
     bool cacheValid;
 
+    std::list<TlbEntry*> freeList;
+
     enum FaultTypes {
         OtherFault = 0,
         PrivViolation = 0x1,
@@ -93,9 +96,6 @@ class TLB : public SimObject
     /** Given an entry id, read that tlb entries' tag. */
     uint64_t TagRead(int entry);
 
-    /** Give an entry id, read that tlb entries' tte */
-    uint64_t TteRead(int entry);
-
     /** Remove all entries from the TLB */
     void invalidateAll();
 
@@ -128,6 +128,10 @@ class TLB : public SimObject
     // Checkpointing
     virtual void serialize(std::ostream &os);
     virtual void unserialize(Checkpoint *cp, const std::string &section);
+
+    /** Give an entry id, read that tlb entries' tte */
+    uint64_t TteRead(int entry);
+
 };
 
 class ITB : public TLB

src/python/m5/objects/SparcTLB.py

@@ -11,4 +11,4 @@ class SparcDTB(SparcTLB):
 
 class SparcITB(SparcTLB):
     type = 'SparcITB'
-    size = 48
+    size = 64