Configure experiment for TCMALLOC_COARSE_LFR_TRACKERS

PiperOrigin-RevId: 769162986
Change-Id: Iebc8743324797b4c03219ae26d2eaf44f0d00eb2

Author: nilayvaish

tcmalloc/experiment_config.h

@@ -23,6 +23,7 @@ namespace tcmalloc {
 enum class Experiment : int {
   // clang-format off
   // go/keep-sorted start
+  TCMALLOC_COARSE_LFR_TRACKERS, // TODO(b/368054442): Complete experiment.
   TCMALLOC_USERMODE_HUGEPAGE_COLLAPSE,  // TODO(b/287498389): Complete experiment.
   TEST_ONLY_L3_AWARE,  // TODO(b/239977380): Complete experiment.
   TEST_ONLY_TCMALLOC_COARSE_LFR_TRACKERS,  // TODO(b/368054442): Complete experiment.
@@ -42,6 +43,7 @@ struct ExperimentConfig {
 // clang-format off
 inline constexpr ExperimentConfig experiments[] = {
     // go/keep-sorted start
+    {Experiment::TCMALLOC_COARSE_LFR_TRACKERS, "TCMALLOC_COARSE_LFR_TRACKERS"},
     {Experiment::TCMALLOC_USERMODE_HUGEPAGE_COLLAPSE, "TCMALLOC_USERMODE_HUGEPAGE_COLLAPSE"},
     {Experiment::TEST_ONLY_L3_AWARE, "TEST_ONLY_L3_AWARE"},
     {Experiment::TEST_ONLY_TCMALLOC_COARSE_LFR_TRACKERS, "TEST_ONLY_TCMALLOC_COARSE_LFR_TRACKERS"},

tcmalloc/parameters.cc

@@ -293,9 +293,10 @@ bool Parameters::sparse_trackers_coarse_longest_free_range() {
   ABSL_CONST_INIT static absl::once_flag flag;
   ABSL_CONST_INIT static std::atomic<bool> v{false};
   absl::base_internal::LowLevelCallOnce(&flag, [&]() {
-    v.store(
-        IsExperimentActive(Experiment::TEST_ONLY_TCMALLOC_COARSE_LFR_TRACKERS),
-        std::memory_order_relaxed);
+    v.store(IsExperimentActive(
+                Experiment::TEST_ONLY_TCMALLOC_COARSE_LFR_TRACKERS) ||
+                IsExperimentActive(Experiment::TCMALLOC_COARSE_LFR_TRACKERS),
+            std::memory_order_relaxed);
   });
   return v;
 }

tcmalloc/variants.bzl

@@ -142,12 +142,20 @@ test_variants = [
         "tags": ["noubsan"],
     },
     {
-        "name": "sparse_trackers_coarse_longest_free_range",
+        "name": "sparse_trackers_coarse_longest_free_range_test",
         "malloc": "//tcmalloc",
         "deps": [
             "//tcmalloc:common_8k_pages",
         ],
-        "env": {"TEST_ONLY_TCMALLOC_COARSE_LFR_TRACKERS": "1"},
+        "env": {"BORG_EXPERIMENTS": "TEST_ONLY_TCMALLOC_COARSE_LFR_TRACKERS"},
+    },
+    {
+        "name": "sparse_trackers_coarse_longest_free_range_exp",
+        "malloc": "//tcmalloc",
+        "deps": [
+            "//tcmalloc:common_8k_pages",
+        ],
+        "env": {"BORG_EXPERIMENTS": "TCMALLOC_COARSE_LFR_TRACKERS"},
     },
     {
         "name": "256k_pages_pow2_sharded_transfer_cache",