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    SubjectRe: [PATCH v3 4/5] tpm: reduce tpm_msleep() time in get_burstcount()
    On Wed, Oct 04, 2017 at 06:29:23AM -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 5msec 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 224842e06105..826a0b9c9201 100644
    > --- a/drivers/char/tpm/tpm_tis_core.c
    > +++ b/drivers/char/tpm/tpm_tis_core.c
    > @@ -226,7 +226,7 @@ static int get_burstcount(struct tpm_chip *chip)
    > burstcnt = (value >> 8) & 0xFFFF;
    > if (burstcnt)
    > return burstcnt;
    > - tpm_msleep(TPM_TIMEOUT);
    > + tpm_msleep(TPM_POLL_SLEEP);
    > } while (time_before(jiffies, stop));
    > return -EBUSY;
    > }
    > --
    > 2.13.3
    >

    Would it make sense to squash this to 3/5 and merge the commit
    messages?

    /Jarkko

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