From 15c309b0b84c2ae36feea4220f0ccef28587db63 Mon Sep 17 00:00:00 2001
From: gingerBill <bill@gingerbill.org>
Date: Mon, 13 Sep 2021 01:39:41 +0100
Subject: [PATCH] Make `permanent_allocator()` thread local

---
 src/common_memory.cpp | 24 +++++++++---------------
 src/main.cpp          |  1 -
 src/parser.cpp        |  3 ---
 3 files changed, 9 insertions(+), 19 deletions(-)

diff --git a/src/common_memory.cpp b/src/common_memory.cpp
index 4d9811b4a..2d7a7a246 100644
--- a/src/common_memory.cpp
+++ b/src/common_memory.cpp
@@ -50,17 +50,16 @@ void virtual_memory_init(void) {
 
 
 struct MemoryBlock {
+	MemoryBlock *prev;
 	u8 *         base; 
 	isize        size;
 	isize        used;
-	MemoryBlock *prev;
 };
 
 struct Arena {
 	MemoryBlock *curr_block;
 	isize        minimum_block_size;
-	bool use_local_mutex;
-	BlockingMutex local_mutex;
+	bool         ignore_mutex;
 };
 
 enum { DEFAULT_MINIMUM_BLOCK_SIZE = 8ll*1024ll*1024ll };
@@ -72,10 +71,6 @@ void virtual_memory_dealloc(MemoryBlock *block);
 void *arena_alloc(Arena *arena, isize min_size, isize alignment);
 void arena_free_all(Arena *arena);
 
-void arena_init_local_mutex(Arena *arena) {
-	mutex_init(&arena->local_mutex);
-	arena->use_local_mutex = true;
-}
 
 isize arena_align_forward_offset(Arena *arena, isize alignment) {
 	isize alignment_offset = 0;
@@ -91,11 +86,9 @@ void *arena_alloc(Arena *arena, isize min_size, isize alignment) {
 	GB_ASSERT(gb_is_power_of_two(alignment));
 	
 	BlockingMutex *mutex = &global_memory_allocator_mutex;
-	if (arena->use_local_mutex) {
-		mutex = &arena->local_mutex;
+	if (!arena->ignore_mutex) {
+		mutex_lock(mutex);
 	}
-		
-	mutex_lock(mutex);
 	
 	isize size = 0;
 	if (arena->curr_block != nullptr) {
@@ -122,7 +115,9 @@ void *arena_alloc(Arena *arena, isize min_size, isize alignment) {
 	curr_block->used += size;
 	GB_ASSERT(curr_block->used <= curr_block->size);
 	
-	mutex_unlock(mutex);
+	if (!arena->ignore_mutex) {
+		mutex_unlock(mutex);
+	}
 	
 	// NOTE(bill): memory will be zeroed by default due to virtual memory 
 	return ptr;	
@@ -296,14 +291,13 @@ GB_ALLOCATOR_PROC(arena_allocator_proc) {
 }
 
 
-gb_global Arena permanent_arena = {};
+gb_global gb_thread_local Arena permanent_arena = {nullptr, DEFAULT_MINIMUM_BLOCK_SIZE, true};
 gbAllocator permanent_allocator() {
 	return arena_allocator(&permanent_arena);
 }
 
-gb_global Arena temporary_arena = {};
 gbAllocator temporary_allocator() {
-	return arena_allocator(&temporary_arena);
+	return permanent_allocator();
 }
 
 
diff --git a/src/main.cpp b/src/main.cpp
index dd9882408..9e35062f2 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -2489,7 +2489,6 @@ int main(int arg_count, char const **arg_ptr) {
 	}
 
 	remove_temp_files(gen);
-	arena_free_all(&temporary_arena);
 
 	if (run_output) {
 	#if defined(GB_SYSTEM_WINDOWS)
diff --git a/src/parser.cpp b/src/parser.cpp
index 722df0d90..e33531fad 100644
--- a/src/parser.cpp
+++ b/src/parser.cpp
@@ -4710,9 +4710,6 @@ ParseFileError init_ast_file(AstFile *f, String fullpath, TokenPos *err_pos) {
 	block_size = ((block_size + page_size-1)/page_size) * page_size;
 	block_size = gb_clamp(block_size, page_size, DEFAULT_MINIMUM_BLOCK_SIZE);
 	f->arena.minimum_block_size = block_size;
-	#if 0
-	arena_init_local_mutex(&f->arena);
-	#endif
 
 	array_init(&f->comments, heap_allocator(), 0, 0);
 	array_init(&f->imports,  heap_allocator(), 0, 0);