Commit 2f169606 authored by Alex Bennée's avatar Alex Bennée
Browse files

tcg: enable tb_lock() for SoftMMU 



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: default avatarAlex Bennée <alex.bennee@linaro.org>
Reviewed-by: default avatarRichard Henderson <rth@twiddle.net>
parent e5143e30

translate-all.c

+1 −14
Original line number Diff line number Diff line
@@ -75,7 +75,7 @@ 
 * mmap_lock.

 */

#ifdef CONFIG_SOFTMMU

#define assert_memory_lock() do { /* nothing */ } while (0)

#define assert_memory_lock() tcg_debug_assert(have_tb_lock)

#else

#define assert_memory_lock() tcg_debug_assert(have_mmap_lock())

#endif
@@ -135,9 +135,7 @@ TCGContext tcg_ctx; 
bool parallel_cpus;



/* translation block context */

#ifdef CONFIG_USER_ONLY

__thread int have_tb_lock;

#endif



static void page_table_config_init(void)

{
@@ -159,40 +157,29 @@ static void page_table_config_init(void) 
    assert(v_l2_levels >= 0);

}



#ifdef CONFIG_USER_ONLY

#define assert_tb_locked() tcg_debug_assert(have_tb_lock)

#define assert_tb_unlocked() tcg_debug_assert(!have_tb_lock)

#else

#define assert_tb_locked()  do { /* nothing */ } while (0)

#define assert_tb_unlocked()  do { /* nothing */ } while (0)

#endif



void tb_lock(void)

{

#ifdef CONFIG_USER_ONLY

    assert_tb_unlocked();

    qemu_mutex_lock(&tcg_ctx.tb_ctx.tb_lock);

    have_tb_lock++;

#endif

}



void tb_unlock(void)

{

#ifdef CONFIG_USER_ONLY

    assert_tb_locked();

    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

}



static TranslationBlock *tb_find_pc(uintptr_t tc_ptr);