From 89a16b1e4294e3664667a151c2f70c84dfac6fd9 Mon Sep 17 00:00:00 2001 From: Sergey Fedorov Date: Fri, 15 Jul 2016 20:58:43 +0300 Subject: tcg: Prepare safe tb_jmp_cache lookup out of tb_lock MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Ensure atomicity of CPU's 'tb_jmp_cache' access for future translation block lookup out of 'tb_lock'. Note that this patch does *not* make CPU's TLB invalidation safe if it is done from some other thread while the CPU is in its execution loop. Signed-off-by: Alex Bennée Signed-off-by: Sergey Fedorov Signed-off-by: Sergey Fedorov Reviewed-by: Alex Bennée Message-Id: <20160715175852.30749-4-sergey.fedorov@linaro.org> Signed-off-by: Paolo Bonzini --- cpu-exec.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'cpu-exec.c') diff --git a/cpu-exec.c b/cpu-exec.c index cf511f1b9a..32b58edb31 100644 --- a/cpu-exec.c +++ b/cpu-exec.c @@ -315,7 +315,7 @@ static TranslationBlock *tb_find_slow(CPUState *cpu, found: /* we add the TB in the virtual pc hash table */ - cpu->tb_jmp_cache[tb_jmp_cache_hash_func(pc)] = tb; + atomic_set(&cpu->tb_jmp_cache[tb_jmp_cache_hash_func(pc)], tb); return tb; } @@ -333,7 +333,7 @@ static inline TranslationBlock *tb_find_fast(CPUState *cpu, is executed. */ cpu_get_tb_cpu_state(env, &pc, &cs_base, &flags); tb_lock(); - tb = cpu->tb_jmp_cache[tb_jmp_cache_hash_func(pc)]; + tb = atomic_rcu_read(&cpu->tb_jmp_cache[tb_jmp_cache_hash_func(pc)]); if (unlikely(!tb || tb->pc != pc || tb->cs_base != cs_base || tb->flags != flags)) { tb = tb_find_slow(cpu, pc, cs_base, flags); -- cgit v1.2.3