From: Mimi Zohar <zohar@linux.vnet.ibm.com>
To: Alexander Steffen <Alexander.Steffen@infineon.com>,
jarkko.sakkinen@linux.intel.com, nayna@linux.vnet.ibm.com,
kgold@linux.vnet.ibm.com, linux-integrity@vger.kernel.org
Subject: Re: [RFC][PATCH 8/9] tpm_tis_spi: add delay between wait state retries
Date: Wed, 17 Jan 2018 12:15:06 -0500 [thread overview]
Message-ID: <1516209306.5820.19.camel@linux.vnet.ibm.com> (raw)
In-Reply-To: <1516055450.6607.91.camel@linux.vnet.ibm.com>
On Mon, 2018-01-15 at 17:30 -0500, Mimi Zohar wrote:
> > What would be a better implementation? No delay and simply retry for
> > five seconds?
> >
> > What TPMs are you using for your tests? At least for the TPMs that I
> > have available for my tests (with a FIFO size of ~256 bytes) I would not
> > expect any wait states for extend commands.
>
> The TPM burstcount is 32. Unfortunately, with this patch set the
> performance on the pi is worse than without it. Without this patch
> set we're seeing ~14 secs for a thousand measurements vs. either ~38s
> or ~23s, depending on the wait sleep length introduced in patch 8/9.
>From my response, it might not have been clear that with all of the
patches, except this one 8/9 calling tpm_msleep(), the performance is
equivalent to without any of the patches. With this patch set, but
with or without the call to tpm_msleep(), it loops 2 or 3 times.
Mimi
next prev parent reply other threads:[~2018-01-17 17:15 UTC|newest]
Thread overview: 35+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-12-08 18:46 [RFC][PATCH 0/9] tpm: fix driver so that burstcount can be safely ignored Alexander Steffen
2017-12-08 18:46 ` [RFC][PATCH 1/9] tpm_tis_core: clean up whitespace Alexander Steffen
2018-01-18 17:11 ` Jarkko Sakkinen
2017-12-08 18:46 ` [RFC][PATCH 2/9] tpm_tis_core: access single TIS registers before doing complex transfers Alexander Steffen
2018-01-18 17:16 ` Jarkko Sakkinen
2017-12-08 18:46 ` [RFC][PATCH 3/9] tpm_tis_core: correctly wait for flags to become zero Alexander Steffen
2018-01-18 17:49 ` Jarkko Sakkinen
2018-01-18 17:58 ` Jarkko Sakkinen
2018-01-18 17:59 ` Jarkko Sakkinen
2017-12-08 18:46 ` [RFC][PATCH 4/9] tpm_tis_core: send all data in single operation Alexander Steffen
2017-12-19 9:01 ` Nayna Jain
2018-01-18 18:04 ` Jarkko Sakkinen
2017-12-08 18:46 ` [RFC][PATCH 5/9] tpm_tis_core: use XDATA_FIFO for transfers if available Alexander Steffen
2018-01-18 18:20 ` Jarkko Sakkinen
2017-12-08 18:46 ` [RFC][PATCH 6/9] tpm_tis_spi: fix sending wrong data during wait state handling Alexander Steffen
2018-01-18 18:26 ` Jarkko Sakkinen
2017-12-08 18:46 ` [RFC][PATCH 7/9] tpm_tis_spi: release CS line when wait state handling fails Alexander Steffen
2018-01-18 18:30 ` Jarkko Sakkinen
2017-12-08 18:46 ` [RFC][PATCH 8/9] tpm_tis_spi: add delay between wait state retries Alexander Steffen
2018-01-11 19:46 ` Mimi Zohar
2018-01-12 8:28 ` Alexander Steffen
2018-01-12 14:53 ` Mimi Zohar
2018-01-15 22:30 ` Mimi Zohar
2018-01-17 17:15 ` Mimi Zohar [this message]
2018-01-17 18:58 ` Alexander Steffen
2018-01-18 18:32 ` Jarkko Sakkinen
2017-12-08 18:46 ` [RFC][PATCH 9/9] tpm: ignore burstcount to improve tpm_tis send() performance Alexander Steffen
2017-12-15 12:04 ` [RFC][PATCH 0/9] tpm: fix driver so that burstcount can be safely ignored Jarkko Sakkinen
2017-12-24 20:41 ` Jarkko Sakkinen
2018-01-04 13:11 ` Alexander.Steffen
2018-01-05 6:46 ` Nayna Jain
2018-01-05 7:38 ` Alexander Steffen
2018-01-08 10:50 ` Jarkko Sakkinen
2018-01-08 10:49 ` Jarkko Sakkinen
2017-12-19 8:53 ` Nayna Jain
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