Revert "Revert "[scudo] Fix the calculating of memory group usage""
This reverts commit 69fe7abb393ba7d6ee9c8ff1429316845b5bad37.
Fixed the arguments order while calling batchGroupBase()
Differential Revision: https://reviews.llvm.org/D136995
GitOrigin-RevId: 9dc5b322d591ff01499a06c95f0caaf14b59f2f3
diff --git a/lib/scudo/standalone/primary32.h b/lib/scudo/standalone/primary32.h
index 6e791a1..a3d908c 100644
--- a/lib/scudo/standalone/primary32.h
+++ b/lib/scudo/standalone/primary32.h
@@ -708,8 +708,10 @@
if (AllocatedGroupSize == 0)
continue;
+ // TransferBatches are pushed in front of BG.Batches. The first one may
+ // not have all caches used.
const uptr NumBlocks = (BG.Batches.size() - 1) * BG.MaxCachedPerBatch +
- BG.Batches.back()->getCount();
+ BG.Batches.front()->getCount();
const uptr BytesInBG = NumBlocks * BlockSize;
// Given the randomness property, we try to release the pages only if the
// bytes used by free blocks exceed certain proportion of allocated
diff --git a/lib/scudo/standalone/primary64.h b/lib/scudo/standalone/primary64.h
index a3684c9..d06a047 100644
--- a/lib/scudo/standalone/primary64.h
+++ b/lib/scudo/standalone/primary64.h
@@ -369,7 +369,7 @@
}
static uptr compactPtrGroup(CompactPtrT CompactPtr) {
- return CompactPtr >> (GroupSizeLog - CompactPtrScale);
+ return static_cast<uptr>(CompactPtr) >> (GroupSizeLog - CompactPtrScale);
}
static uptr batchGroupBase(uptr Base, uptr GroupId) {
return (GroupId << GroupSizeLog) + Base;
@@ -702,16 +702,49 @@
BG.PushedBlocks - BG.PushedBlocksAtLastCheckpoint;
if (PushedBytesDelta * BlockSize < PageSize)
continue;
+
+ // Group boundary does not necessarily have the same alignment as Region.
+ // It may sit across a Region boundary. Which means that we may have the
+ // following two cases,
+ //
+ // 1. Group boundary sits before RegionBeg.
+ //
+ // (BatchGroupBeg)
+ // batchGroupBase RegionBeg BatchGroupEnd
+ // | | |
+ // v v v
+ // +------------+----------------+
+ // \ /
+ // ------ GroupSize ------
+ //
+ // 2. Group boundary sits after RegionBeg.
+ //
+ // (BatchGroupBeg)
+ // RegionBeg batchGroupBase BatchGroupEnd
+ // | | |
+ // v v v
+ // +-----------+-----------------------------+
+ // \ /
+ // ------ GroupSize ------
+ //
+ // Note that in the first case, the group range before RegionBeg is never
+ // used. Therefore, while calculating the used group size, we should
+ // exclude that part to get the correct size.
+ const uptr BatchGroupBeg =
+ Max(batchGroupBase(CompactPtrBase, BG.GroupId), Region->RegionBeg);
+ DCHECK_GE(AllocatedUserEnd, BatchGroupBeg);
const uptr BatchGroupEnd =
- batchGroupBase(BG.GroupId, CompactPtrBase) + GroupSize;
+ batchGroupBase(CompactPtrBase, BG.GroupId) + GroupSize;
const uptr AllocatedGroupSize = AllocatedUserEnd >= BatchGroupEnd
- ? GroupSize
- : AllocatedUserEnd - BatchGroupEnd;
+ ? BatchGroupEnd - BatchGroupBeg
+ : AllocatedUserEnd - BatchGroupBeg;
if (AllocatedGroupSize == 0)
continue;
+ // TransferBatches are pushed in front of BG.Batches. The first one may
+ // not have all caches used.
const uptr NumBlocks = (BG.Batches.size() - 1) * BG.MaxCachedPerBatch +
- BG.Batches.back()->getCount();
+ BG.Batches.front()->getCount();
const uptr BytesInBG = NumBlocks * BlockSize;
// Given the randomness property, we try to release the pages only if the
// bytes used by free blocks exceed certain proportion of group size. Note
