On 10/08/2015 17:27, address@hidden wrote:
From: KONRAD Frederic <address@hidden>
This protects TBContext with tb_lock to make tb_* thread safe.
We can still have issue with tb_flush in case of multithread TCG:
An other CPU can be executing code during a flush.
This can be fixed later by making all other TCG thread exiting before calling
tb_flush().
tb_find_slow is separated into tb_find_slow and tb_find_physical as the whole
tb_find_slow doesn't require to lock the tb.
Signed-off-by: KONRAD Frederic <address@hidden>
Changes:
[...]
@@ -675,6 +710,7 @@ static inline void code_gen_alloc(size_t tb_size)
CODE_GEN_AVG_BLOCK_SIZE;
tcg_ctx.tb_ctx.tbs =
g_malloc(tcg_ctx.code_gen_max_blocks * sizeof(TranslationBlock));
+ qemu_mutex_init(&tcg_ctx.tb_ctx.tb_lock);
}
/* Must be called before using the QEMU cpus. 'tb_size' is the size
@@ -699,16 +735,22 @@ bool tcg_enabled(void)
return tcg_ctx.code_gen_buffer != NULL;
}
-/* Allocate a new translation block. Flush the translation buffer if
- too many translation blocks or too much generated code. */
+/*
+ * Allocate a new translation block. Flush the translation buffer if
+ * too many translation blocks or too much generated code.
+ * tb_alloc is not thread safe but tb_gen_code is protected by a mutex so this
+ * function is called only by one thread.
+ */
static TranslationBlock *tb_alloc(target_ulong pc)
{
- TranslationBlock *tb;
+ TranslationBlock *tb = NULL;
if (tcg_ctx.tb_ctx.nb_tbs >= tcg_ctx.code_gen_max_blocks ||
(tcg_ctx.code_gen_ptr - tcg_ctx.code_gen_buffer) >=
tcg_ctx.code_gen_buffer_max_size) {
- return NULL;
+ tb = &tcg_ctx.tb_ctx.tbs[tcg_ctx.tb_ctx.nb_tbs++];
+ tb->pc = pc;
+ tb->cflags = 0;
Missed this wrong unreverted part which in the end doesn't do a tb_flush
when required and crashes!
Fixing that allows me to boot with jessie and virt.