From c67a13020247055e072eff259f1cd41857dc4226 Mon Sep 17 00:00:00 2001
From: John Hawthorn <john@hawthorn.email>
Date: Wed, 27 Nov 2024 12:57:17 -0800
Subject: [PATCH] Categorize as GC

---
 ext/vernier/vernier.cc        | 20 ++++++++++++--------
 lib/vernier/output/firefox.rb |  2 +-
 2 files changed, 13 insertions(+), 9 deletions(-)

diff --git a/ext/vernier/vernier.cc b/ext/vernier/vernier.cc
index 9f232680..0621229a 100644
--- a/ext/vernier/vernier.cc
+++ b/ext/vernier/vernier.cc
@@ -234,12 +234,8 @@ class RawSample {
             return;
         }
 
-        if (rb_during_gc()) {
-          gc = true;
-        } else {
-          len = rb_profile_frames(0, MAX_LEN, frames, lines);
-          this->offset = std::min(offset, len);
-        }
+        len = rb_profile_frames(0, MAX_LEN, frames, lines);
+        this->offset = std::min(offset, len);
     }
 
     void clear() {
@@ -858,7 +854,8 @@ class GCMarkerTable: public MarkerTable {
 enum Category{
     CATEGORY_NORMAL,
     CATEGORY_IDLE,
-    CATEGORY_STALLED
+    CATEGORY_STALLED,
+    CATEGORY_GC
 };
 
 class ObjectSampleList {
@@ -1552,6 +1549,8 @@ class TimeCollector : public BaseCollector {
     unsigned int allocation_interval;
     unsigned int allocation_tick = 0;
 
+    atomic_bool gc_running;
+
     VALUE tp_newobj = Qnil;
 
     static void newobj_i(VALUE tpval, void *data) {
@@ -1589,7 +1588,10 @@ class TimeCollector : public BaseCollector {
         BaseCollector::write_meta(meta, result);
         rb_hash_aset(meta, sym("interval"), ULL2NUM(interval.microseconds()));
         rb_hash_aset(meta, sym("allocation_interval"), ULL2NUM(allocation_interval));
+    }
 
+    void set_gc_running(bool value) {
+        gc_running = value;
     }
 
     private:
@@ -1652,7 +1654,7 @@ class TimeCollector : public BaseCollector {
                     } else if (sample.sample.empty()) {
                         // fprintf(stderr, "skipping GC sample\n");
                     } else {
-                        record_sample(sample.sample, sample_start, thread, CATEGORY_NORMAL);
+                        record_sample(sample.sample, sample_start, thread, gc_running ? CATEGORY_GC : CATEGORY_NORMAL);
                     }
                 } else if (thread.state == Thread::State::SUSPENDED) {
                     thread.samples.record_sample(
@@ -1725,9 +1727,11 @@ class TimeCollector : public BaseCollector {
                 collector->gc_markers.record_gc_end_sweep();
                 break;
             case RUBY_INTERNAL_EVENT_GC_ENTER:
+                collector->set_gc_running(true);
                 collector->gc_markers.record_gc_entered();
                 break;
             case RUBY_INTERNAL_EVENT_GC_EXIT:
+                collector->set_gc_running(false);
                 collector->gc_markers.record_gc_leave();
                 break;
         }
diff --git a/lib/vernier/output/firefox.rb b/lib/vernier/output/firefox.rb
index f8ac3dce..2d6d6dd2 100644
--- a/lib/vernier/output/firefox.rb
+++ b/lib/vernier/output/firefox.rb
@@ -34,7 +34,7 @@ def initialize
           add_category(name: "Idle", color: "transparent")
           add_category(name: "Stalled", color: "transparent")
 
-          add_category(name: "GC", color: "red")
+          add_category(name: "GC", color: "orange")
           add_category(name: "cfunc", color: "yellow", matcher: "<cfunc>")
 
           add_category(name: "Thread", color: "grey")