From 0a51de094da6fc523d141de4e8b8f42a18a0a73b Mon Sep 17 00:00:00 2001
From: Ryan Fleury <ryan.j.fleury@gmail.com>
Date: Sun, 18 May 2025 12:58:44 -0700
Subject: [PATCH] switch to stripe-cv-based waiting mechanism on nonzero scope
 touches

---
 src/ctrl/ctrl_core.c |  6 ++----
 src/dbgi/dbgi.c      | 20 +++++++++-----------
 src/dbgi/dbgi.h      |  3 ++-
 3 files changed, 13 insertions(+), 16 deletions(-)

diff --git a/src/ctrl/ctrl_core.c b/src/ctrl/ctrl_core.c
index bf855bf1..8e92c34e 100644
--- a/src/ctrl/ctrl_core.c
+++ b/src/ctrl/ctrl_core.c
@@ -1434,10 +1434,8 @@ ctrl_scope_close(CTRL_Scope *scope)
   for(CTRL_ScopeCallStackTouch *t = scope->first_call_stack_touch, *next = 0; t != 0; t = next)
   {
     next = t->next;
-    if(!ins_atomic_u64_dec_eval(&t->node->scope_touch_count))
-    {
-      os_condition_variable_broadcast(t->stripe->cv);
-    }
+    ins_atomic_u64_dec_eval(&t->node->scope_touch_count);
+    os_condition_variable_broadcast(t->stripe->cv);
     SLLStackPush(ctrl_tctx->free_call_stack_touch, t);
   }
   SLLStackPush(ctrl_tctx->free_scope, scope);
diff --git a/src/dbgi/dbgi.c b/src/dbgi/dbgi.c
index b4afa856..96f0b480 100644
--- a/src/dbgi/dbgi.c
+++ b/src/dbgi/dbgi.c
@@ -279,6 +279,7 @@ di_scope_close(DI_Scope *scope)
     if(t->node != 0)
     {
       ins_atomic_u64_dec_eval(&t->node->touch_count);
+      os_condition_variable_broadcast(t->stripe->cv);
     }
     if(t->search_node != 0)
     {
@@ -291,7 +292,7 @@ di_scope_close(DI_Scope *scope)
 }
 
 internal void
-di_scope_touch_node__stripe_mutex_r_guarded(DI_Scope *scope, DI_Node *node)
+di_scope_touch_node__stripe_mutex_r_guarded(DI_Scope *scope, DI_Stripe *stripe, DI_Node *node)
 {
   if(node != 0)
   {
@@ -309,6 +310,7 @@ di_scope_touch_node__stripe_mutex_r_guarded(DI_Scope *scope, DI_Node *node)
   MemoryZeroStruct(touch);
   SLLQueuePush(scope->first_touch, scope->last_touch, touch);
   touch->node = node;
+  touch->stripe = stripe;
 }
 
 internal void
@@ -529,6 +531,7 @@ di_close(DI_Key *key)
     DI_Slot *slot = &di_shared->slots[slot_idx];
     DI_Stripe *stripe = &di_shared->stripes[stripe_idx];
     log_infof("close_debug_info: {\"%S\", 0x%I64x}\n", key_normalized.path, key_normalized.min_timestamp);
+    B32 closed = 0;
     OS_MutexScopeW(stripe->rw_mutex)
     {
       //- rjf: find existing node
@@ -540,16 +543,8 @@ di_close(DI_Key *key)
         node->ref_count -= 1;
         if(node->ref_count == 0) for(;;)
         {
-          //- rjf: wait for touch count to go to 0
-          if(ins_atomic_u64_eval(&node->touch_count) != 0)
-          {
-            os_rw_mutex_drop_w(stripe->rw_mutex);
-            for(U64 start_t = os_now_microseconds(); os_now_microseconds() <= start_t + 250;);
-            os_rw_mutex_take_w(stripe->rw_mutex);
-          }
-          
           //- rjf: release
-          if(node->ref_count == 0 && ins_atomic_u64_eval(&node->touch_count) == 0)
+          if(ins_atomic_u64_eval(&node->touch_count) == 0)
           {
             di_string_release__stripe_mutex_w_guarded(stripe, node->key.path);
             if(node->file_base != 0)
@@ -572,6 +567,9 @@ di_close(DI_Key *key)
             SLLStackPush(stripe->free_node, node);
             break;
           }
+          
+          //- rjf: wait for touch count to go to 0
+          os_condition_variable_wait_rw_w(stripe->cv, stripe->rw_mutex, max_U64);
         }
       }
     }
@@ -617,7 +615,7 @@ di_rdi_from_key(DI_Scope *scope, DI_Key *key, U64 endt_us)
       //- rjf: parse done -> touch, grab result
       if(node != 0 && node->parse_done)
       {
-        di_scope_touch_node__stripe_mutex_r_guarded(scope, node);
+        di_scope_touch_node__stripe_mutex_r_guarded(scope, stripe, node);
         result = &node->rdi;
         break;
       }
diff --git a/src/dbgi/dbgi.h b/src/dbgi/dbgi.h
index c663c3e7..ca8b8e77 100644
--- a/src/dbgi/dbgi.h
+++ b/src/dbgi/dbgi.h
@@ -218,6 +218,7 @@ struct DI_Touch
 {
   DI_Touch *next;
   DI_Node *node;
+  DI_Stripe *stripe;
   DI_SearchNode *search_node;
   DI_SearchStripe *search_stripe;
 };
@@ -410,7 +411,7 @@ internal void di_init(void);
 
 internal DI_Scope *di_scope_open(void);
 internal void di_scope_close(DI_Scope *scope);
-internal void di_scope_touch_node__stripe_mutex_r_guarded(DI_Scope *scope, DI_Node *node);
+internal void di_scope_touch_node__stripe_mutex_r_guarded(DI_Scope *scope, DI_Stripe *stripe, DI_Node *node);
 internal void di_scope_touch_search_node__stripe_mutex_r_guarded(DI_Scope *scope, DI_SearchStripe *stripe, DI_SearchNode *node);
 
 ////////////////////////////////