mem-cache: Optimize sector valid and secure check

Previously a loop was being done to check whether the
block was valid/secure or not. Variables have been
added to skip this loop and save and update sector
block state when sub-blocks are validated, invalidated
and secured.

Change-Id: Ie1734f7dfda9698c7bf22a1fcbfc47ffb9239cea
Signed-off-by: Daniel R. Carvalho <odanrc@yahoo.com.br>
Reviewed-on: https://gem5-review.googlesource.com/c/14363
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>

1 files changed, 50 insertions, 12 deletions

diff --git a/src/mem/cache/tags/sector_blk.cc b/src/mem/cache/tags/sector_blk.cc
index de9153639..93b1961d8 100644
--- a/src/mem/cache/tags/sector_blk.cc
+++ b/src/mem/cache/tags/sector_blk.cc
@@ -72,6 +72,27 @@ SectorSubBlk::getTag() const
 }
 
 void
+SectorSubBlk::setValid()
+{
+    CacheBlk::setValid();
+    _sectorBlk->validateSubBlk();
+}
+
+void
+SectorSubBlk::setSecure()
+{
+    CacheBlk::setSecure();
+    _sectorBlk->setSecure();
+}
+
+void
+SectorSubBlk::invalidate()
+{
+    CacheBlk::invalidate();
+    _sectorBlk->invalidateSubBlk();
+}
+
+void
 SectorSubBlk::insert(const Addr tag, const bool is_secure,
                      const int src_master_ID, const uint32_t task_ID)
 {
@@ -94,28 +115,23 @@ SectorSubBlk::print() const
                     getSectorOffset());
 }
 
+SectorBlk::SectorBlk()
+    : ReplaceableEntry(), _tag(MaxAddr), _validCounter(0), _secureBit(false)
+{
+}
+
 bool
 SectorBlk::isValid() const
 {
     // If any of the blocks in the sector is valid, so is the sector
-    for (const auto& blk : blks) {
-        if (blk->isValid()) {
-            return true;
-        }
-    }
-    return false;
+    return _validCounter > 0;
 }
 
 bool
 SectorBlk::isSecure() const
 {
     // If any of the valid blocks in the sector is secure, so is the sector
-    for (const auto& blk : blks) {
-        if (blk->isValid()) {
-            return blk->isSecure();
-        }
-    }
-    return false;
+    return _secureBit;
 }
 
 void
@@ -129,3 +145,25 @@ SectorBlk::getTag() const
 {
     return _tag;
 }
+
+void
+SectorBlk::validateSubBlk()
+{
+    _validCounter++;
+}
+
+void
+SectorBlk::invalidateSubBlk()
+{
+    // If all sub-blocks have been invalidated, the sector becomes invalid,
+    // so clear secure bit
+    if (--_validCounter == 0) {
+        _secureBit = false;
+    }
+}
+
+void
+SectorBlk::setSecure()
+{
+    _secureBit = true;
+}