Hi Alex,
On Wed, Jun 14, 2017 at 10:02 AM, Alex Bennée <alex.ben...@linaro.org> wrote:
> Just a little precursor re-factoring before I was going to add a trace
> point:
>
> - single return point, defaulting to tcg_ctx.code_gen_epilogue
> - move cs_base, pc and flags inside the jump cache hit scope
> - calculate the tb_jmp_cache hash once
>
> Signed-off-by: Alex Bennée <alex.ben...@linaro.org>
> ---
> tcg-runtime.c | 35 +++++++++++++++++++----------------
> 1 file changed, 19 insertions(+), 16 deletions(-)
Phew, glad you got this figured out! I tested it on the images I have
and it works. Please add:
Tested-by: Pranith Kumar <bobby.pr...@gmail.com>
>
> diff --git a/tcg-runtime.c b/tcg-runtime.c
> index 7fa90ce508..f4bfa9cea6 100644
> --- a/tcg-runtime.c
> +++ b/tcg-runtime.c
> @@ -147,30 +147,33 @@ uint64_t HELPER(ctpop_i64)(uint64_t arg)
> void *HELPER(lookup_tb_ptr)(CPUArchState *env, target_ulong addr)
> {
> CPUState *cpu = ENV_GET_CPU(env);
> + unsigned int addr_hash = tb_jmp_cache_hash_func(addr);
> + void *code_ptr = NULL;
> TranslationBlock *tb;
> - target_ulong cs_base, pc;
> - uint32_t flags;
>
> - tb = atomic_rcu_read(&cpu->tb_jmp_cache[tb_jmp_cache_hash_func(addr)]);
> + tb = atomic_rcu_read(&cpu->tb_jmp_cache[addr_hash]);
> if (likely(tb)) {
> + target_ulong cs_base, pc;
> + uint32_t flags;
> +
> cpu_get_tb_cpu_state(env, &pc, &cs_base, &flags);
> +
> if (likely(tb->pc == addr && tb->cs_base == cs_base &&
> tb->flags == flags)) {
> - goto found;
> - }
> - tb = tb_htable_lookup(cpu, addr, cs_base, flags);
> - if (likely(tb)) {
> - atomic_set(&cpu->tb_jmp_cache[tb_jmp_cache_hash_func(addr)], tb);
> - goto found;
> + code_ptr = tb->tc_ptr;
> + } else {
> + /* If we didn't find it in the jmp_cache we still might
> + * find it in the global tb_htable
> + */
> + tb = tb_htable_lookup(cpu, addr, cs_base, flags);
> + if (likely(tb)) {
> + atomic_set(&cpu->tb_jmp_cache[addr_hash], tb);
> + code_ptr = tb->tc_ptr;
> + }
> }
> }
> - return tcg_ctx.code_gen_epilogue;
> - found:
> - qemu_log_mask_and_addr(CPU_LOG_EXEC, addr,
> - "Chain %p [%d: " TARGET_FMT_lx "] %s\n",
> - tb->tc_ptr, cpu->cpu_index, addr,
> - lookup_symbol(addr));
> - return tb->tc_ptr;
> +
> + return code_ptr ? code_ptr : tcg_ctx.code_gen_epilogue;
> }
>
> void HELPER(exit_atomic)(CPUArchState *env)
> --
> 2.13.0
>
>
