Re: [PATCH v4 3/4] tpm: reduce tpm polling delay in tpm_tis_core

[Jarkko Sakkinen]

On Wed, Oct 18, 2017 at 06:24:47PM +0300, Jarkko Sakkinen wrote:
> On Tue, Oct 17, 2017 at 04:32:31PM -0400, Nayna Jain wrote:
> > The existing wait_for_tpm_stat() polls for the chip status after
> > 5msec sleep. As per TCG ddwg input, it is expected that tpm might
> > return status in few usec. So, reducing the delay in polling to
> > 1msec.
> > Similarly, get_burstcount() function sleeps for 5msec before
> > retrying for next query to burstcount in a loop. If it takes
> > lesser time for TPM to return, this 5msec delay is longer than
> > necessary.
> > 
> > After this change, performance on a TPM 1.2 with an 8 byte
> > burstcount for 1000 extends improved from ~14sec to ~9sec.
> > 
> > Signed-off-by: Nayna Jain <nayna@xxxxxxxxxxxxxxxxxx>
> 
> Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@xxxxxxxxxxxxxxx>

Tested-by: Jarkko Sakkinen <jarkkko.sakkinen@xxxxxxxxxxxxxxx>

/Jarkko