Re: [Qemu-devel] [PATCH v1 7/7] target-arm: Call the pmccntr_sync function when swapping ELs

[Peter Crosthwaite]

On Tue, Jun 24, 2014 at 11:12 AM, Alistair Francis
<address@hidden> wrote:
> Call the new pmccntr_sync() function when there is a possibility
> of swapping ELs (I.E. when there is an exception)
>
> Signed-off-by: Alistair Francis <address@hidden>
> ---
>
>  target-arm/helper-a64.c |    5 +++++
>  target-arm/helper.c     |    7 +++++++
>  target-arm/op_helper.c  |    6 ++++++
>  3 files changed, 18 insertions(+), 0 deletions(-)
>
> diff --git a/target-arm/helper-a64.c b/target-arm/helper-a64.c
> index 2b4ce6a..b61174f 100644
> --- a/target-arm/helper-a64.c
> +++ b/target-arm/helper-a64.c
> @@ -446,6 +446,8 @@ void aarch64_cpu_do_interrupt(CPUState *cs)
>      target_ulong addr = env->cp15.vbar_el[1];
>      int i;
>
> +    pmccntr_sync(env);
> +
>      if (arm_current_pl(env) == 0) {
>          if (env->aarch64) {
>              addr += 0x400;
> @@ -484,6 +486,7 @@ void aarch64_cpu_do_interrupt(CPUState *cs)
>          addr += 0x100;
>          break;
>      default:
> +        pmccntr_sync(env);

Can you localise just the one sync->sync pair around the el change
logic itself to avoid having to catch all the return paths?

Regards,
Peter

>          cpu_abort(cs, "Unhandled exception 0x%x\n", cs->exception_index);
>      }
>
> @@ -511,4 +514,6 @@ void aarch64_cpu_do_interrupt(CPUState *cs)
>
>      env->pc = addr;
>      cs->interrupt_request |= CPU_INTERRUPT_EXITTB;
> +
> +    pmccntr_sync(env);
>  }
> diff --git a/target-arm/helper.c b/target-arm/helper.c
> index 3e0a9a1..7c0a57f 100644
> --- a/target-arm/helper.c
> +++ b/target-arm/helper.c
> @@ -3417,6 +3417,8 @@ void arm_cpu_do_interrupt(CPUState *cs)
>
>      assert(!IS_M(env));
>
> +    pmccntr_sync(env);
> +
>      arm_log_exception(cs->exception_index);
>
>      /* TODO: Vectored interrupt controller.  */
> @@ -3447,6 +3449,7 @@ void arm_cpu_do_interrupt(CPUState *cs)
>                    && (env->uncached_cpsr & CPSR_M) != ARM_CPU_MODE_USR) {
>                  env->regs[0] = do_arm_semihosting(env);
>                  qemu_log_mask(CPU_LOG_INT, "...handled as semihosting 
> call\n");
> +                pmccntr_sync(env);
>                  return;
>              }
>          }
> @@ -3465,6 +3468,7 @@ void arm_cpu_do_interrupt(CPUState *cs)
>                  env->regs[15] += 2;
>                  env->regs[0] = do_arm_semihosting(env);
>                  qemu_log_mask(CPU_LOG_INT, "...handled as semihosting 
> call\n");
> +                pmccntr_sync(env);
>                  return;
>              }
>          }
> @@ -3508,6 +3512,7 @@ void arm_cpu_do_interrupt(CPUState *cs)
>          offset = 4;
>          break;
>      default:
> +        pmccntr_sync(env);
>          cpu_abort(cs, "Unhandled exception 0x%x\n", cs->exception_index);
>          return; /* Never happens.  Keep compiler happy.  */
>      }
> @@ -3540,6 +3545,8 @@ void arm_cpu_do_interrupt(CPUState *cs)
>      env->regs[14] = env->regs[15] + offset;
>      env->regs[15] = addr;
>      cs->interrupt_request |= CPU_INTERRUPT_EXITTB;
> +
> +    pmccntr_sync(env);
>  }
>
>  /* Check section/page access permissions.
> diff --git a/target-arm/op_helper.c b/target-arm/op_helper.c
> index 9c1ef52..07ab30b 100644
> --- a/target-arm/op_helper.c
> +++ b/target-arm/op_helper.c
> @@ -376,6 +376,8 @@ void HELPER(exception_return)(CPUARMState *env)
>      uint32_t spsr = env->banked_spsr[spsr_idx];
>      int new_el, i;
>
> +    pmccntr_sync(env);
> +
>      if (env->pstate & PSTATE_SP) {
>          env->sp_el[cur_el] = env->xregs[31];
>      } else {
> @@ -418,6 +420,8 @@ void HELPER(exception_return)(CPUARMState *env)
>          env->pc = env->elr_el[cur_el];
>      }
>
> +    pmccntr_sync(env);
> +
>      return;
>
>  illegal_return:
> @@ -433,6 +437,8 @@ illegal_return:
>      spsr &= PSTATE_NZCV | PSTATE_DAIF;
>      spsr |= pstate_read(env) & ~(PSTATE_NZCV | PSTATE_DAIF);
>      pstate_write(env, spsr);
> +
> +    pmccntr_sync(env);
>  }
>
>  /* ??? Flag setting arithmetic is awkward because we need to do comparisons.
> --
> 1.7.1
>
>