Re: [PATCH v3 08/12] hw/tpm: Make TRACE_TPM_UTIL_SHOW_BUFFER check local to tpm_util.c

[Stefan Berger]

On 6/12/20 4:54 AM, Philippe Mathieu-Daudé wrote:
> The trace_event_get_state_backends() call is useful to avoid
> making extensive calls (usually preparing arguments passed to
> the tracing framework. In this case, the extensive work is
> done in tpm_util_show_buffer(), and the arguments used to
> call it don't involve extra processing. Simplify by moving
> the TRACE_TPM_UTIL_SHOW_BUFFER check to tpm_util_show_buffer.
>
> Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>

Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>


> ---
>   hw/tpm/tpm_tis_common.c | 8 ++------
>   hw/tpm/tpm_util.c       | 3 +++
>   2 files changed, 5 insertions(+), 6 deletions(-)
>
> diff --git a/hw/tpm/tpm_tis_common.c b/hw/tpm/tpm_tis_common.c
> index 94704870f6..1779b4fc1e 100644
> --- a/hw/tpm/tpm_tis_common.c
> +++ b/hw/tpm/tpm_tis_common.c
> @@ -78,9 +78,7 @@ static void tpm_tis_sts_set(TPMLocality *l, uint32_t flags)
>    */
>   static void tpm_tis_tpm_send(TPMState *s, uint8_t locty)
>   {
> -    if (trace_event_get_state_backends(TRACE_TPM_UTIL_SHOW_BUFFER)) {
> -        tpm_util_show_buffer(s->buffer, s->be_buffer_size, "To TPM");
> -    }
> +    tpm_util_show_buffer(s->buffer, s->be_buffer_size, "To TPM");
>   
>       /*
>        * rw_offset serves as length indicator for length of data;
> @@ -246,9 +244,7 @@ void tpm_tis_request_completed(TPMState *s, int ret)
>       s->loc[locty].state = TPM_TIS_STATE_COMPLETION;
>       s->rw_offset = 0;
>   
> -    if (trace_event_get_state_backends(TRACE_TPM_UTIL_SHOW_BUFFER)) {
> -        tpm_util_show_buffer(s->buffer, s->be_buffer_size, "From TPM");
> -    }
> +    tpm_util_show_buffer(s->buffer, s->be_buffer_size, "From TPM");
>   
>       if (TPM_TIS_IS_VALID_LOCTY(s->next_locty)) {
>           tpm_tis_abort(s);
> diff --git a/hw/tpm/tpm_util.c b/hw/tpm/tpm_util.c
> index c0a0f3d71f..12f19465c5 100644
> --- a/hw/tpm/tpm_util.c
> +++ b/hw/tpm/tpm_util.c
> @@ -357,6 +357,9 @@ void tpm_util_show_buffer(const unsigned char *buffer,
>       size_t len, i;
>       char *line_buffer, *p;
>   
> +    if (!trace_event_get_state_backends(TRACE_TPM_UTIL_SHOW_BUFFER)) {
> +        return;
> +    }
>       len = MIN(tpm_cmd_get_size(buffer), buffer_size);
>   
>       /*