[Qemu-devel] [RFC v4 21/28] tcg: enable tb_lock() for SoftMMU

["Alex Bennée" <alex.bennee@linaro.org>]

tb_lock() has long been used for linux-user mode to protect code
generation. By enabling it now we prepare for MTTCG and ensure all code
generation is serialised by this lock. The other major structure that
needs protecting is the l1_map and its PageDesc structures. For the
SoftMMU case we also use tb_lock() to protect these structures instead
of linux-user mmap_lock() which as the name suggests serialises updates
to the structure as a result of guest mmap operations.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>

---
v4
  - split from main tcg: enable thread-per-vCPU patch
---
 translate-all.c | 18 +++++-------------
 1 file changed, 5 insertions(+), 13 deletions(-)

diff --git a/translate-all.c b/translate-all.c
index c53ae8c..cfb009a 100644
--- a/translate-all.c
+++ b/translate-all.c
@@ -82,7 +82,11 @@
 #endif
 
 #ifdef CONFIG_SOFTMMU
-#define assert_memory_lock() do { /* nothing */ } while (0)
+#define assert_memory_lock() do {           \
+        if (DEBUG_MEM_LOCKS) {              \
+            g_assert(have_tb_lock);         \
+        }                                   \
+    } while (0)
 #else
 #define assert_memory_lock() do {               \
         if (DEBUG_MEM_LOCKS) {                  \
@@ -146,36 +150,28 @@ static void *l1_map[V_L1_SIZE];
 TCGContext tcg_ctx;
 
 /* translation block context */
-#ifdef CONFIG_USER_ONLY
 __thread int have_tb_lock;
-#endif
 
 void tb_lock(void)
 {
-#ifdef CONFIG_USER_ONLY
     assert(!have_tb_lock);
     qemu_mutex_lock(&tcg_ctx.tb_ctx.tb_lock);
     have_tb_lock++;
-#endif
 }
 
 void tb_unlock(void)
 {
-#ifdef CONFIG_USER_ONLY
     assert(have_tb_lock);
     have_tb_lock--;
     qemu_mutex_unlock(&tcg_ctx.tb_ctx.tb_lock);
-#endif
 }
 
 void tb_lock_reset(void)
 {
-#ifdef CONFIG_USER_ONLY
     if (have_tb_lock) {
         qemu_mutex_unlock(&tcg_ctx.tb_ctx.tb_lock);
         have_tb_lock = 0;
     }
-#endif
 }
 
 #ifdef DEBUG_LOCKING
@@ -184,15 +180,11 @@ void tb_lock_reset(void)
 #define DEBUG_TB_LOCKS 0
 #endif
 
-#ifdef CONFIG_SOFTMMU
-#define assert_tb_lock() do { /* nothing */ } while (0)
-#else
 #define assert_tb_lock() do {               \
         if (DEBUG_TB_LOCKS) {               \
             g_assert(have_tb_lock);         \
         }                                   \
     } while (0)
-#endif
 
 
 static TranslationBlock *tb_find_pc(uintptr_t tc_ptr);
-- 
2.7.4