From 241f72a438a75754171b82e9cb81aafc8886d327 Mon Sep 17 00:00:00 2001
From: Florian Engelhardt <florian.engelhardt@datadoghq.com>
Date: Mon, 27 Jul 2026 16:39:30 +0200
Subject: [PATCH] perf(profiling): avoid FFI call on allocation hot path

Read executor_globals.current_execute_data directly on NTS builds instead of calling through the C FFI wrapper for every allocation and reallocation. Keep the existing wrapper on ZTS builds.

A 60-second macOS sample reduced get_current_execute_data self time from 0.412% (207/50,210 main-thread samples) to 0.002% (1/49,737). Known allocation-hook self time fell from 4.184% to 3.601%, a 13.9% relative reduction. Repeated end-to-end throughput remained within system scheduling noise.

Validation: cargo test (22 passed); allocation sampling-distance, memory-peak, and GC PHPTs passed.
---
 profiling/src/allocation/allocation_ge84.rs | 7 ++++---
 profiling/src/allocation/allocation_le83.rs | 7 ++++---
 profiling/src/allocation/mod.rs             | 9 +++++++++
 3 files changed, 17 insertions(+), 6 deletions(-)

diff --git a/profiling/src/allocation/allocation_ge84.rs b/profiling/src/allocation/allocation_ge84.rs
index 606f32df14..80670585aa 100644
--- a/profiling/src/allocation/allocation_ge84.rs
+++ b/profiling/src/allocation/allocation_ge84.rs
@@ -1,5 +1,6 @@
 use crate::allocation::{
-    allocation_profiling_stats_should_collect, collect_allocation, untrack_allocation,
+    allocation_profiling_stats_should_collect, collect_allocation, current_execute_data,
+    untrack_allocation,
 };
 use crate::bindings as zend;
 use crate::PROFILER_NAME;
@@ -306,7 +307,7 @@ unsafe fn alloc_prof_malloc_impl(len: size_t) -> *mut c_void {
 
     // during startup, minit, rinit, ... current_execute_data is null
     // we are only interested in allocations during userland operations
-    if zend::ddog_php_prof_get_current_execute_data().is_null() {
+    if current_execute_data().is_null() {
         return ptr;
     }
 
@@ -505,7 +506,7 @@ unsafe fn alloc_prof_realloc_no_untrack_impl(prev_ptr: *mut c_void, len: size_t)
 unsafe fn alloc_prof_realloc_sample(ptr: *mut c_void, len: size_t) -> *mut c_void {
     // during startup, minit, rinit, ... current_execute_data is null
     // we are only interested in allocations during userland operations
-    if zend::ddog_php_prof_get_current_execute_data().is_null() {
+    if current_execute_data().is_null() {
         return ptr;
     }
 
diff --git a/profiling/src/allocation/allocation_le83.rs b/profiling/src/allocation/allocation_le83.rs
index c36de739e9..12a1b37c58 100644
--- a/profiling/src/allocation/allocation_le83.rs
+++ b/profiling/src/allocation/allocation_le83.rs
@@ -1,5 +1,6 @@
 use crate::allocation::{
-    allocation_profiling_stats_should_collect, collect_allocation, untrack_allocation,
+    allocation_profiling_stats_should_collect, collect_allocation, current_execute_data,
+    untrack_allocation,
 };
 use crate::bindings::{
     self as zend, datadog_php_install_handler, datadog_php_zif_handler,
@@ -300,7 +301,7 @@ unsafe extern "C" fn alloc_prof_malloc(len: size_t) -> *mut c_void {
 
     // during startup, minit, rinit, ... current_execute_data is null
     // we are only interested in allocations during userland operations
-    if zend::ddog_php_prof_get_current_execute_data().is_null() {
+    if current_execute_data().is_null() {
         return ptr;
     }
 
@@ -431,7 +432,7 @@ unsafe fn alloc_prof_realloc_no_untrack_impl(prev_ptr: *mut c_void, len: size_t)
 unsafe fn alloc_prof_realloc_sample(ptr: *mut c_void, len: size_t) -> *mut c_void {
     // during startup, minit, rinit, ... current_execute_data is null
     // we are only interested in allocations during userland operations
-    if zend::ddog_php_prof_get_current_execute_data().is_null() {
+    if current_execute_data().is_null() {
         return ptr;
     }
 
diff --git a/profiling/src/allocation/mod.rs b/profiling/src/allocation/mod.rs
index 9d4f46d53c..20f4d2280a 100644
--- a/profiling/src/allocation/mod.rs
+++ b/profiling/src/allocation/mod.rs
@@ -39,6 +39,15 @@ pub(crate) unsafe fn get_zend_mm_state() -> *mut Cell<ZendMMState> {
     ptr::addr_of_mut!((*globals).zend_mm_state)
 }
 
+#[inline(always)]
+pub(crate) unsafe fn current_execute_data() -> *mut zend::zend_execute_data {
+    #[cfg(not(php_zts))]
+    return ptr::addr_of!(zend::executor_globals.current_execute_data).read();
+
+    #[cfg(php_zts)]
+    zend::ddog_php_prof_get_current_execute_data()
+}
+
 /// Macros for accessing ZendMMState from PHP globals.
 /// These are shared between PHP 8.3- and 8.4+ implementations.
 /// They are exported at the crate root and can be used in submodules.