From mboxrd@z Thu Jan 1 00:00:00 1970 From: jarkko.sakkinen@linux.intel.com (Jarkko Sakkinen) Date: Thu, 19 Oct 2017 17:22:44 +0300 Subject: [PATCH v4 3/4] tpm: reduce tpm polling delay in tpm_tis_core In-Reply-To: <20171018152447.b6scwbbmulrfzymw@linux.intel.com> References: <20171017203232.2262-1-nayna@linux.vnet.ibm.com> <20171017203232.2262-4-nayna@linux.vnet.ibm.com> <20171018152447.b6scwbbmulrfzymw@linux.intel.com> Message-ID: <20171019142244.7aaqyc3hizzt7n7p@linux.intel.com> To: linux-security-module@vger.kernel.org List-Id: linux-security-module.vger.kernel.org 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 > > Reviewed-by: Jarkko Sakkinen Tested-by: Jarkko Sakkinen /Jarkko -- To unsubscribe from this list: send the line "unsubscribe linux-security-module" in the body of a message to majordomo at vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html