We acquire mmap lock and tb lock in one order and release them in a different order. This does not need to be that way.
This patch was inspired by a previous patch by Emilio G. Cota (https://lists.gnu.org/archive/html/qemu-devel/2016-08/msg03785.html). Signed-off-by: Pranith Kumar <bobby.pr...@gmail.com> --- cpu-exec.c | 12 +++--------- 1 file changed, 3 insertions(+), 9 deletions(-) diff --git a/cpu-exec.c b/cpu-exec.c index aa8318d864..f4a00f5047 100644 --- a/cpu-exec.c +++ b/cpu-exec.c @@ -318,7 +318,6 @@ static inline TranslationBlock *tb_find(CPUState *cpu, TranslationBlock *tb; target_ulong cs_base, pc; uint32_t flags; - bool have_tb_lock = false; /* we record a subset of the CPU state. It will always be the same before a given translated block @@ -336,7 +335,6 @@ static inline TranslationBlock *tb_find(CPUState *cpu, */ mmap_lock(); tb_lock(); - have_tb_lock = true; /* There's a chance that our desired tb has been translated while * taking the locks so we check again inside the lock. @@ -347,6 +345,7 @@ static inline TranslationBlock *tb_find(CPUState *cpu, tb = tb_gen_code(cpu, pc, cs_base, flags, 0); } + tb_unlock(); mmap_unlock(); } @@ -364,17 +363,12 @@ static inline TranslationBlock *tb_find(CPUState *cpu, #endif /* See if we can patch the calling TB. */ if (last_tb && !qemu_loglevel_mask(CPU_LOG_TB_NOCHAIN)) { - if (!have_tb_lock) { - tb_lock(); - have_tb_lock = true; - } if (!tb->invalid) { + tb_lock(); tb_add_jump(last_tb, tb_exit, tb); + tb_unlock(); } } - if (have_tb_lock) { - tb_unlock(); - } return tb; } -- 2.11.0
