Messages in this thread | | | Date | Tue, 12 Sep 2017 18:00:11 -0700 | From | Jarkko Sakkinen <> | Subject | Re: [PATCH v2 3/4] tpm: reduce tpm_msleep() time in get_burstcount() |
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On Wed, Sep 06, 2017 at 08:56:38AM -0400, Nayna Jain wrote: > Currently, get_burstcount() function sleeps for 5msec in a loop > before retrying for next query to burstcount. However, if it takes > lesser time for TPM to return, this 5 msec delay is longer > than necessary. > > This patch replaces the tpm_msleep time from 5msec to 1msec. > > After this change, performance on a TPM 1.2 with an 8 byte > burstcount for 1000 extends improved from ~10sec to ~9sec. > > Signed-off-by: Nayna Jain <nayna@linux.vnet.ibm.com> > Acked-by: Mimi Zohar <zohar@linux.vnet.ibm.com> > --- > drivers/char/tpm/tpm_tis_core.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c > index d1eab29cb447..d710bbc4608b 100644 > --- a/drivers/char/tpm/tpm_tis_core.c > +++ b/drivers/char/tpm/tpm_tis_core.c > @@ -169,7 +169,7 @@ static int get_burstcount(struct tpm_chip *chip) > burstcnt = (value >> 8) & 0xFFFF; > if (burstcnt) > return burstcnt; > - tpm_msleep(TPM_TIMEOUT); > + tpm_msleep(1); > } while (time_before(jiffies, stop)); > return -EBUSY; > } > -- > 2.13.3
How did you pick 1 ms delay? Should there be a constant defining it?
/Jarkko
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