From mboxrd@z Thu Jan 1 00:00:00 1970 From: jarkko.sakkinen@linux.intel.com (Jarkko Sakkinen) Date: Tue, 24 Apr 2018 19:27:52 +0300 Subject: [PATCH v2 1/2] tpm: reduce poll sleep time in tpm_transmit() In-Reply-To: <20180417131246.434-2-nayna@linux.vnet.ibm.com> References: <20180417131246.434-1-nayna@linux.vnet.ibm.com> <20180417131246.434-2-nayna@linux.vnet.ibm.com> Message-ID: <20180424162752.GC5119@linux.intel.com> To: linux-security-module@vger.kernel.org List-Id: linux-security-module.vger.kernel.org On Tue, Apr 17, 2018 at 09:12:45AM -0400, Nayna Jain wrote: > The TPM polling code in tpm_transmit sleeps in each loop iteration for > 5 msecs. However, the TPM might return earlier, and thus waiting for > 5 msecs adds an unnecessary delay. This patch reduces the polling sleep > time in tpm_transmit() from 5 msecs to 1 msecs. I'm not sure what TPM returning earlier has to do with this. TPM probably never returns exactly in the spec defined timeout/duration. I just don't understand reasoning in this paragraph. > Additionally, this patch renames TPM_POLL_SLEEP and moves it to tpm.h as > an enum value. > > After this change, performance on a TPM 1.2 with an 8 byte burstcount > for 1000 extends improved from ~14 sec to ~10.7 sec. You cannot give absolute numbers without a context (platform, software). > Signed-off-by: Nayna Jain /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