Remove the unified alloc feature from the HugePageFiller

PiperOrigin-RevId: 662669066 Change-Id: I6aa7b178b717f8eec658fb27ad57ca0e96fb41f4
google · Aug 13, 2024 · a40d2c7 · a40d2c7
1 parent ff292bc
commit a40d2c7
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Showing 8 changed files with 51 additions and 144 deletions.
diff --git a/tcmalloc/global_stats.cc b/tcmalloc/global_stats.cc
@@ -550,10 +550,6 @@ void DumpStats(Printer* out, int level) {
                 Parameters::huge_region_demand_based_release() ? 1 : 0);
     out->printf("PARAMETER tcmalloc_release_pages_from_huge_region %d\n",
                 Parameters::release_pages_from_huge_region() ? 1 : 0);
-    out->printf(
-        "PARAMETER tcmalloc_separate_allocs_for_few_and_many_objects_spans "
-        "%d\n",
-        Parameters::separate_allocs_for_few_and_many_objects_spans());
     out->printf("PARAMETER tcmalloc_use_wider_slabs %d\n",
                 tc_globals.cpu_cache().UseWiderSlabs() ? 1 : 0);
     out->printf("PARAMETER tcmalloc_configure_size_class_max_capacity %d\n",
@@ -756,9 +752,6 @@ void DumpStatsInPbtxt(Printer* out, int level) {
                   Parameters::profile_sampling_interval());
   region.PrintRaw("percpu_vcpu_type",
                   PerCpuTypeString(subtle::percpu::GetRseqVcpuMode()));
-  region.PrintBool(
-      "separate_allocs_for_few_and_many_objects_spans",
-      Parameters::separate_allocs_for_few_and_many_objects_spans());
   region.PrintBool("tcmalloc_use_wider_slabs",
                    tc_globals.cpu_cache().UseWiderSlabs());
   region.PrintBool("tcmalloc_configure_size_class_max_capacity",

diff --git a/tcmalloc/huge_page_aware_allocator.h b/tcmalloc/huge_page_aware_allocator.h
@@ -122,10 +122,6 @@ class StaticForwarder {
 struct HugePageAwareAllocatorOptions {
   MemoryTag tag;
   HugeRegionUsageOption use_huge_region_more_often = huge_region_option();
-  HugePageFillerAllocsOption allocs_for_sparse_and_dense_spans =
-      Parameters::separate_allocs_for_few_and_many_objects_spans()
-          ? HugePageFillerAllocsOption::kSeparateAllocs
-          : HugePageFillerAllocsOption::kUnifiedAllocs;
   absl::Duration huge_cache_time = Parameters::huge_cache_release_time();
 };
 
@@ -400,8 +396,7 @@ inline HugePageAwareAllocator<Forwarder>::HugePageAwareAllocator(
     : PageAllocatorInterface("HugePageAware", options.tag),
       unback_(*this),
       unback_without_lock_(*this),
-      filler_(options.allocs_for_sparse_and_dense_spans, unback_,
-              unback_without_lock_),
+      filler_(unback_, unback_without_lock_),
       regions_(options.use_huge_region_more_often),
       vm_allocator_(*this),
       metadata_allocator_(*this),

diff --git a/tcmalloc/huge_page_aware_allocator_fuzz.cc b/tcmalloc/huge_page_aware_allocator_fuzz.cc
@@ -85,8 +85,7 @@ void FuzzHPAA(const std::string& s) {
   // [1] - HugeRegionsMode.
   // [2] - HugeCache release time
   // [3:4] - Reserved.
-  // [5] - Determine if we use separate filler allocs based on number of
-  // objects per span.
+  // [5] - (available)
   // [6:12] - Reserved.
   //
   // TODO(b/271282540): Convert these to strongly typed fuzztest parameters.
@@ -115,11 +114,6 @@ void FuzzHPAA(const std::string& s) {
           ? HugeRegionUsageOption::kDefault
           : HugeRegionUsageOption::kUseForAllLargeAllocs;
 
-  const HugePageFillerAllocsOption allocs_option =
-      static_cast<uint8_t>(data[5]) >= 128
-          ? HugePageFillerAllocsOption::kUnifiedAllocs
-          : HugePageFillerAllocsOption::kSeparateAllocs;
-
   const int32_t huge_cache_release_s = std::max<int32_t>(data[2], 1);
 
   // data[6:12] - Reserve additional bytes for any features we might want to add
@@ -134,7 +128,6 @@ void FuzzHPAA(const std::string& s) {
   HugePageAwareAllocatorOptions options;
   options.tag = tag;
   options.use_huge_region_more_often = huge_region_option;
-  options.allocs_for_sparse_and_dense_spans = allocs_option;
   options.huge_cache_time = absl::Seconds(huge_cache_release_s);
   HugePageAwareAllocator<FakeStaticForwarderWithUnback>* allocator;
   allocator =

diff --git a/tcmalloc/huge_page_filler.h b/tcmalloc/huge_page_filler.h
@@ -262,13 +262,11 @@ template <class TrackerType>
 class HugePageFiller {
  public:
   explicit HugePageFiller(
-      HugePageFillerAllocsOption allocs_option,
       MemoryModifyFunction& unback ABSL_ATTRIBUTE_LIFETIME_BOUND,
       MemoryModifyFunction& unback_without_lock ABSL_ATTRIBUTE_LIFETIME_BOUND);
-  HugePageFiller(Clock clock, HugePageFillerAllocsOption allocs_options,
-                 MemoryModifyFunction& unback ABSL_ATTRIBUTE_LIFETIME_BOUND,
-                 MemoryModifyFunction& unback_without_lock
-                     ABSL_ATTRIBUTE_LIFETIME_BOUND);
+  HugePageFiller(
+      Clock clock, MemoryModifyFunction& unback ABSL_ATTRIBUTE_LIFETIME_BOUND,
+      MemoryModifyFunction& unback_without_lock ABSL_ATTRIBUTE_LIFETIME_BOUND);
 
   typedef TrackerType Tracker;
 
@@ -446,8 +444,6 @@ class HugePageFiller {
   // n_used_partial_released_ is the number of pages which have been allocated
   // from the hugepages in the set regular_alloc_partial_released.
   Length n_used_partial_released_[AccessDensityPrediction::kPredictionCounts];
-  const HugePageFillerAllocsOption allocs_for_sparse_and_dense_spans_ =
-      HugePageFillerAllocsOption::kUnifiedAllocs;
 
   // RemoveFromFillerList pt from the appropriate PageTrackerList.
   void RemoveFromFillerList(TrackerType* pt);
@@ -639,19 +635,17 @@ inline Length PageTracker::free_pages() const {
 
 template <class TrackerType>
 inline HugePageFiller<TrackerType>::HugePageFiller(
-    HugePageFillerAllocsOption allocs_option, MemoryModifyFunction& unback,
-    MemoryModifyFunction& unback_without_lock)
+    MemoryModifyFunction& unback, MemoryModifyFunction& unback_without_lock)
     : HugePageFiller(Clock{.now = absl::base_internal::CycleClock::Now,
                            .freq = absl::base_internal::CycleClock::Frequency},
-                     allocs_option, unback, unback_without_lock) {}
+                     unback, unback_without_lock) {}
 
 // For testing with mock clock
 template <class TrackerType>
 inline HugePageFiller<TrackerType>::HugePageFiller(
-    Clock clock, HugePageFillerAllocsOption allocs_option,
-    MemoryModifyFunction& unback, MemoryModifyFunction& unback_without_lock)
-    : allocs_for_sparse_and_dense_spans_(allocs_option),
-      size_(NHugePages(0)),
+    Clock clock, MemoryModifyFunction& unback,
+    MemoryModifyFunction& unback_without_lock)
+    : size_(NHugePages(0)),
       fillerstats_tracker_(clock, absl::Minutes(10), absl::Minutes(5)),
       clock_(clock),
       unback_(unback),
@@ -731,8 +725,6 @@ HugePageFiller<TrackerType>::TryGet(Length n, SpanAllocInfo span_alloc_info) {
 
   bool was_released = false;
   const AccessDensityPrediction type =
-      ABSL_PREDICT_TRUE(allocs_for_sparse_and_dense_spans_ ==
-                        HugePageFillerAllocsOption::kSeparateAllocs) &&
               IsDenseSpan(span_alloc_info.density)
           ? AccessDensityPrediction::kDense
           : AccessDensityPrediction::kSparse;
@@ -858,8 +850,6 @@ inline void HugePageFiller<TrackerType>::Contribute(
   TC_ASSERT_EQ(pt->released_pages(), Length(0));
 
   const AccessDensityPrediction type =
-      ABSL_PREDICT_TRUE(allocs_for_sparse_and_dense_spans_ ==
-                        HugePageFillerAllocsOption::kSeparateAllocs) &&
               IsDenseSpan(span_alloc_info.density)
           ? AccessDensityPrediction::kDense
           : AccessDensityPrediction::kSparse;
@@ -1924,8 +1914,6 @@ inline void HugePageFiller<TrackerType>::RemoveFromFillerList(TrackerType* pt) {
   size_t chunk = IndexFor(pt);
   size_t i = ListFor(longest, chunk);
   const AccessDensityPrediction type =
-      ABSL_PREDICT_TRUE(allocs_for_sparse_and_dense_spans_ ==
-                        HugePageFillerAllocsOption::kSeparateAllocs) &&
               pt->HasDenseSpans()
           ? AccessDensityPrediction::kDense
           : AccessDensityPrediction::kSparse;
@@ -1957,8 +1945,6 @@ inline void HugePageFiller<TrackerType>::AddToFillerList(TrackerType* pt) {
 
   size_t i = ListFor(longest, chunk);
   const AccessDensityPrediction type =
-      ABSL_PREDICT_TRUE(allocs_for_sparse_and_dense_spans_ ==
-                        HugePageFillerAllocsOption::kSeparateAllocs) &&
               pt->HasDenseSpans()
           ? AccessDensityPrediction::kDense
           : AccessDensityPrediction::kSparse;

diff --git a/tcmalloc/huge_page_filler_fuzz.cc b/tcmalloc/huge_page_filler_fuzz.cc
@@ -105,7 +105,7 @@ void FuzzFiller(const std::string& s) {
   // HugePageFiller.
   //
   // [0] - (available)
-  // [1] - We choose the separate_allocs_for_few_and_many_objects_spans
+  // [1] - (available)
   // [2] - (available)
   //
   // Afterwards, we read 5 bytes at a time until the buffer is exhausted.
@@ -116,16 +116,10 @@ void FuzzFiller(const std::string& s) {
   //                  For example, this input can provide a Length to
   //                  allocate, or the index of the previous allocation to
   //                  deallocate.
-
-  const HugePageFillerAllocsOption allocs_for_few_and_many_objects_spans =
-      static_cast<uint8_t>(data[1]) >= 128
-          ? HugePageFillerAllocsOption::kSeparateAllocs
-          : HugePageFillerAllocsOption::kUnifiedAllocs;
   data += kInitBytes;
   size -= kInitBytes;
 
   HugePageFiller<PageTracker> filler(Clock{.now = mock_clock, .freq = freq},
-                                     allocs_for_few_and_many_objects_spans,
                                      unback, unback);
 
   struct Alloc {