Re: [RFC v18 08/15] i386: split smm helper (softmmu)

[Claudio Fontana]

On 2/12/21 1:36 PM, Claudio Fontana wrote:
> smm is only really useful for softmmu, split in two modules
> around the CONFIG_USER_ONLY, in order to remove the ifdef
> and use the build system instead.
> 
> Signed-off-by: Claudio Fontana <cfontana@suse.de>
> ---
>  target/i386/helper.h                       |  4 ++++
>  target/i386/tcg/seg_helper.c               |  2 ++
>  target/i386/tcg/{ => softmmu}/smm_helper.c | 19 ++-----------------
>  target/i386/tcg/translate.c                |  2 ++
>  target/i386/tcg/meson.build                |  1 -
>  target/i386/tcg/softmmu/meson.build        |  1 +
>  6 files changed, 11 insertions(+), 18 deletions(-)
>  rename target/i386/tcg/{ => softmmu}/smm_helper.c (98%)
> 
> diff --git a/target/i386/helper.h b/target/i386/helper.h
> index c2ae2f7e61..8ffda4cdc6 100644
> --- a/target/i386/helper.h
> +++ b/target/i386/helper.h
> @@ -70,7 +70,11 @@ DEF_HELPER_1(clac, void, env)
>  DEF_HELPER_1(stac, void, env)
>  DEF_HELPER_3(boundw, void, env, tl, int)
>  DEF_HELPER_3(boundl, void, env, tl, int)
> +
> +#ifndef CONFIG_USER_ONLY
>  DEF_HELPER_1(rsm, void, env)
> +#endif /* !CONFIG_USER_ONLY */
> +
>  DEF_HELPER_2(into, void, env, int)
>  DEF_HELPER_2(cmpxchg8b_unlocked, void, env, tl)
>  DEF_HELPER_2(cmpxchg8b, void, env, tl)
> diff --git a/target/i386/tcg/seg_helper.c b/target/i386/tcg/seg_helper.c
> index 180d47f0e9..f0cb1bffe7 100644
> --- a/target/i386/tcg/seg_helper.c
> +++ b/target/i386/tcg/seg_helper.c
> @@ -1351,7 +1351,9 @@ bool x86_cpu_exec_interrupt(CPUState *cs, int 
> interrupt_request)
>      case CPU_INTERRUPT_SMI:
>          cpu_svm_check_intercept_param(env, SVM_EXIT_SMI, 0, 0);
>          cs->interrupt_request &= ~CPU_INTERRUPT_SMI;
> +#ifndef CONFIG_USER_ONLY
>          do_smm_enter(cpu);
> +#endif
>          break;
>      case CPU_INTERRUPT_NMI:
>          cpu_svm_check_intercept_param(env, SVM_EXIT_NMI, 0, 0);
> diff --git a/target/i386/tcg/smm_helper.c 
> b/target/i386/tcg/softmmu/smm_helper.c
> similarity index 98%
> rename from target/i386/tcg/smm_helper.c
> rename to target/i386/tcg/softmmu/smm_helper.c
> index 62d027abd3..ee53b26629 100644
> --- a/target/i386/tcg/smm_helper.c
> +++ b/target/i386/tcg/softmmu/smm_helper.c
> @@ -1,5 +1,5 @@
>  /*
> - *  x86 SMM helpers
> + *  x86 SMM helpers (softmmu-only)
>   *
>   *  Copyright (c) 2003 Fabrice Bellard
>   *
> @@ -18,27 +18,14 @@
>   */
>  
>  #include "qemu/osdep.h"
> -#include "qemu/main-loop.h"
>  #include "cpu.h"
>  #include "exec/helper-proto.h"
>  #include "exec/log.h"
> -#include "helper-tcg.h"
> +#include "tcg/helper-tcg.h"
>  
>  
>  /* SMM support */
>  
> -#if defined(CONFIG_USER_ONLY)
> -
> -void do_smm_enter(X86CPU *cpu)
> -{
> -}
> -
> -void helper_rsm(CPUX86State *env)
> -{
> -}
> -
> -#else
> -
>  #ifdef TARGET_X86_64
>  #define SMM_REVISION_ID 0x00020064
>  #else
> @@ -330,5 +317,3 @@ void helper_rsm(CPUX86State *env)
>      qemu_log_mask(CPU_LOG_INT, "SMM: after RSM\n");
>      log_cpu_state_mask(CPU_LOG_INT, CPU(cpu), CPU_DUMP_CCOP);
>  }
> -
> -#endif /* !CONFIG_USER_ONLY */
> diff --git a/target/i386/tcg/translate.c b/target/i386/tcg/translate.c
> index af1faf9342..5075ac4830 100644
> --- a/target/i386/tcg/translate.c
> +++ b/target/i386/tcg/translate.c
> @@ -8321,7 +8321,9 @@ static target_ulong disas_insn(DisasContext *s, 
> CPUState *cpu)
>              goto illegal_op;
>          gen_update_cc_op(s);
>          gen_jmp_im(s, s->pc - s->cs_base);
> +#ifndef CONFIG_USER_ONLY
>          gen_helper_rsm(cpu_env);
> +#endif /* CONFIG_USER_ONLY */
>          gen_eob(s);
>          break;

Hello Alex,

this is something I wanted to bring in the foreground:

while before we were generating an empty helper call for CONFIG_USER_ONLY,
now we are not generating anything.



>      case 0x1b8: /* SSE4.2 popcnt */
> diff --git a/target/i386/tcg/meson.build b/target/i386/tcg/meson.build
> index 68fa0c3187..ec5daa1edc 100644
> --- a/target/i386/tcg/meson.build
> +++ b/target/i386/tcg/meson.build
> @@ -8,7 +8,6 @@ i386_ss.add(when: 'CONFIG_TCG', if_true: files(
>    'misc_helper.c',
>    'mpx_helper.c',
>    'seg_helper.c',
> -  'smm_helper.c',
>    'svm_helper.c',
>    'tcg-cpu.c',
>    'translate.c'), if_false: files('tcg-stub.c'))
> diff --git a/target/i386/tcg/softmmu/meson.build 
> b/target/i386/tcg/softmmu/meson.build
> index 4ab30cc32e..35ba16dc3d 100644
> --- a/target/i386/tcg/softmmu/meson.build
> +++ b/target/i386/tcg/softmmu/meson.build
> @@ -1,3 +1,4 @@
>  i386_softmmu_ss.add(when: ['CONFIG_TCG', 'CONFIG_SOFTMMU'], if_true: files(
>    'tcg-cpu.c',
> +  'smm_helper.c',
>  ))
>