[hwasan] Switch to 64 allocator with a dense size class map.

Summary:
Replace the 32-bit allocator with a 64-bit one with a non-constant
base address, and reduce both the number of size classes and the maximum
size of per-thread caches.

As measured on [1], this reduces average weighted memory overhead
(MaxRSS) from 26% to 12% over stock android allocator. These numbers
include overhead from code instrumentation and hwasan shadow (i.e. not a
pure allocator benchmark).

This switch also enables release-to-OS functionality, which is not
implemented in the 32-bit allocator. I have not seen any effect from
that on the benchmark.

[1] https://android.googlesource.com/platform/system/extras/+/master/memory_replay/

Reviewers: vitalybuka, kcc

Subscribers: kubamracek, cryptoad, llvm-commits

Differential Revision: https://reviews.llvm.org/D56239

llvm-svn: 350370
This commit is contained in:
Evgeniy Stepanov 2019-01-03 23:19:02 +00:00
parent ef4afca2ad
commit d398471a63
5 changed files with 11 additions and 15 deletions

View File

@ -45,28 +45,22 @@ struct HwasanMapUnmapCallback {
};
static const uptr kMaxAllowedMallocSize = 2UL << 30; // 2G
static const uptr kRegionSizeLog = 20;
static const uptr kNumRegions = SANITIZER_MMAP_RANGE_SIZE >> kRegionSizeLog;
typedef TwoLevelByteMap<(kNumRegions >> 12), 1 << 12> ByteMap;
struct AP32 {
static const uptr kSpaceBeg = 0;
static const u64 kSpaceSize = SANITIZER_MMAP_RANGE_SIZE;
struct AP64 {
static const uptr kSpaceBeg = ~0ULL;
static const uptr kSpaceSize = 0x2000000000ULL;
static const uptr kMetadataSize = sizeof(Metadata);
typedef __sanitizer::CompactSizeClassMap SizeClassMap;
static const uptr kRegionSizeLog = __hwasan::kRegionSizeLog;
typedef __sanitizer::VeryDenseSizeClassMap SizeClassMap;
using AddressSpaceView = LocalAddressSpaceView;
using ByteMap = __hwasan::ByteMap;
typedef HwasanMapUnmapCallback MapUnmapCallback;
static const uptr kFlags = 0;
};
typedef SizeClassAllocator32<AP32> PrimaryAllocator;
typedef SizeClassAllocator64<AP64> PrimaryAllocator;
typedef SizeClassAllocatorLocalCache<PrimaryAllocator> AllocatorCache;
typedef LargeMmapAllocator<HwasanMapUnmapCallback> SecondaryAllocator;
typedef CombinedAllocator<PrimaryAllocator, AllocatorCache,
SecondaryAllocator> Allocator;
void AllocatorSwallowThreadLocalCache(AllocatorCache *cache);
class HwasanChunkView {

View File

@ -34,15 +34,15 @@ class CombinedAllocator {
"SecondaryAllocator is using wrong AddressSpaceView");
void InitLinkerInitialized(s32 release_to_os_interval_ms) {
stats_.InitLinkerInitialized();
primary_.Init(release_to_os_interval_ms);
secondary_.InitLinkerInitialized();
stats_.InitLinkerInitialized();
}
void Init(s32 release_to_os_interval_ms) {
stats_.Init();
primary_.Init(release_to_os_interval_ms);
secondary_.Init();
stats_.Init();
}
void *Allocate(AllocatorCache *cache, uptr size, uptr alignment) {

View File

@ -237,3 +237,6 @@ typedef SizeClassMap<2, 5, 9, 16, 64, 14> VeryCompactSizeClassMap;
// allowing for denser per-class arrays, smaller memory footprint and usually
// better performances in threaded environments.
typedef SizeClassMap<3, 4, 8, 17, 8, 10> DenseSizeClassMap;
// Similar to VeryCompact map above, this one has a small number of different
// size classes, and also reduced thread-local caches.
typedef SizeClassMap<2, 5, 9, 16, 8, 10> VeryDenseSizeClassMap;

View File

@ -43,7 +43,6 @@ int main(int argc, char **argv) {
// CHECK80-RIGHT: allocated heap chunk; size: 32 offset:
// CHECK80-RIGHT: is located 50 bytes to the right of 30-byte region
//
// CHECKm30: allocated heap chunk; size: 32 offset: 2
// CHECKm30: is located 30 bytes to the left of 30-byte region
//
// CHECKMm30: is a large allocated heap chunk; size: 1003520 offset: -30

View File

@ -23,7 +23,7 @@ int main() {
// CHECK: [[TYPE]] of size 1 at {{.*}} tags: [[PTR_TAG:[0-9a-f][0-9a-f]]]/[[MEM_TAG:[0-9a-f][0-9a-f]]] (ptr/mem)
// CHECK: #0 {{.*}} in main {{.*}}use-after-free.c:[[@LINE-2]]
// Offset is 5 or 11 depending on left/right alignment.
// CHECK: is a small unallocated heap chunk; size: 16 offset: {{5|11}}
// CHECK: is a small unallocated heap chunk; size: 32 offset: {{5|11}}
// CHECK: is located 5 bytes inside of 10-byte region
//
// CHECK: freed by thread {{.*}} here: