Add helper to print malloc_stats()

The `malloc_stats()` API has been useful to debug issues with memory fragmentation (see <DataDog/libdatadog#293>) so let's keep a helper to make it easy to access.
DataDog · Jan 31, 2024 · 0fa8b1e · 0fa8b1e
1 parent 482021c
commit 0fa8b1e
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Showing 2 changed files with 12 additions and 0 deletions.
diff --git a/ext/ddtrace_profiling_native_extension/extconf.rb b/ext/ddtrace_profiling_native_extension/extconf.rb
@@ -130,6 +130,8 @@ def add_compiler_flag(flag)
   $defs << '-DHAVE_PTHREAD_GETCPUCLOCKID'
 end
 
+have_func 'malloc_stats'
+
 # On older Rubies, rb_postponed_job_preregister/rb_postponed_job_trigger did not exist
 $defs << '-DNO_POSTPONED_TRIGGER' if RUBY_VERSION < '3.3'
 

diff --git a/ext/ddtrace_profiling_native_extension/profiling.c b/ext/ddtrace_profiling_native_extension/profiling.c
@@ -1,6 +1,7 @@
 #include <ruby.h>
 #include <ruby/thread.h>
 #include <errno.h>
+#include <malloc.h>
 
 #include "clock_id.h"
 #include "helpers.h"
@@ -32,6 +33,7 @@ static void holding_the_gvl_signal_handler(DDTRACE_UNUSED int _signal, DDTRACE_U
 static VALUE _native_trigger_holding_the_gvl_signal_handler_on(DDTRACE_UNUSED VALUE _self, VALUE background_thread);
 static VALUE _native_enforce_success(DDTRACE_UNUSED VALUE _self, VALUE syserr_errno, VALUE with_gvl);
 static void *trigger_enforce_success(void *trigger_args);
+static VALUE _native_malloc_stats(DDTRACE_UNUSED VALUE _self);
 
 void DDTRACE_EXPORT Init_ddtrace_profiling_native_extension(void) {
   VALUE datadog_module = rb_define_module("Datadog");
@@ -65,6 +67,7 @@ void DDTRACE_EXPORT Init_ddtrace_profiling_native_extension(void) {
   rb_define_singleton_method(testing_module, "_native_install_holding_the_gvl_signal_handler", _native_install_holding_the_gvl_signal_handler, 0);
   rb_define_singleton_method(testing_module, "_native_trigger_holding_the_gvl_signal_handler_on", _native_trigger_holding_the_gvl_signal_handler_on, 1);
   rb_define_singleton_method(testing_module, "_native_enforce_success", _native_enforce_success, 2);
+  rb_define_singleton_method(testing_module, "_native_malloc_stats", _native_malloc_stats, 0);
 }
 
 static VALUE native_working_p(DDTRACE_UNUSED VALUE _self) {
@@ -249,3 +252,10 @@ static void *trigger_enforce_success(void *trigger_args) {
   ENFORCE_SUCCESS_NO_GVL(syserr_errno);
   return NULL;
 }
+
+static VALUE _native_malloc_stats(DDTRACE_UNUSED VALUE _self) {
+  #ifdef HAVE_MALLOC_STATS
+    malloc_stats();
+  #endif
+  return Qnil;
+}