From 171c3c551a5aea02871d322493361d66c4d9815d Mon Sep 17 00:00:00 2001
From: Yonggang Luo <luoyonggang@gmail.com>
Date: Sat, 24 Sep 2022 15:28:52 +0800
Subject: [PATCH] util: Fixes debug_get_option_* thread safety by set
 initialized=true after the value get
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Signed-off-by: Yonggang Luo <luoyonggang@gmail.com>
Acked-by: Marek Olšák <marek.olsak@amd.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/18764>
---
 src/util/u_debug.h | 17 +++++++++--------
 1 file changed, 9 insertions(+), 8 deletions(-)

diff --git a/src/util/u_debug.h b/src/util/u_debug.h
index 43b2a41e19d19..a2afd86643940 100644
--- a/src/util/u_debug.h
+++ b/src/util/u_debug.h
@@ -46,6 +46,7 @@
 #endif
 
 #include "util/os_misc.h"
+#include "util/u_atomic.h"
 #include "util/detect_os.h"
 #include "util/macros.h"
 
@@ -374,9 +375,9 @@ debug_get_option_ ## suffix (void) \
 { \
    static bool initialized = false; \
    static const char * value; \
-   if (!initialized) { \
-      initialized = true; \
+   if (unlikely(!p_atomic_read_relaxed(&initialized))) { \
       value = debug_get_option(name, dfault); \
+      p_atomic_set(&initialized, true); \
    } \
    return value; \
 }
@@ -397,9 +398,9 @@ debug_get_option_ ## sufix (void) \
 { \
    static bool initialized = false; \
    static bool value; \
-   if (!initialized) { \
-      initialized = true; \
+   if (unlikely(!p_atomic_read_relaxed(&initialized))) { \
       value = debug_get_bool_option(name, dfault); \
+      p_atomic_set(&initialized, true); \
    } \
    return value; \
 }
@@ -410,9 +411,9 @@ debug_get_option_ ## sufix (void) \
 { \
    static bool initialized = false; \
    static long value; \
-   if (!initialized) { \
-      initialized = true; \
+   if (unlikely(!p_atomic_read_relaxed(&initialized))) { \
       value = debug_get_num_option(name, dfault); \
+      p_atomic_set(&initialized, true); \
    } \
    return value; \
 }
@@ -423,9 +424,9 @@ debug_get_option_ ## sufix (void) \
 { \
    static bool initialized = false; \
    static unsigned long value; \
-   if (!initialized) { \
-      initialized = true; \
+   if (unlikely(!p_atomic_read_relaxed(&initialized))) { \
       value = debug_get_flags_option(name, flags, dfault); \
+      p_atomic_set(&initialized, true); \
    } \
    return value; \
 }