> -----Original Message----- > From: dev [mailto:dev-bounces at dpdk.org] On Behalf Of Jerin Jacob > Sent: Thursday, August 18, 2016 5:22 PM > To: dev at dpdk.org > Cc: thomas.monjalon at 6wind.com; jianbo.liu at linaro.org; > viktorin at rehivetech.com; Jerin Jacob <jerin.jacob at caviumnetworks.com> > Subject: [dpdk-dev] [PATCH] eal/armv8: high-resolution cycle counter > > Existing cntvct_el0 based rte_rdtsc() provides portable means to get wall > clock > counter at user space. Typically it runs at <= 100MHz. > > The alternative method to enable rte_rdtsc() for high resolution wall clock > counter is through armv8 PMU subsystem. > The PMU cycle counter runs at CPU frequency, However, access to PMU cycle > counter from user space is not enabled by default in the arm64 linux kernel. > It is possible to enable cycle counter at user space access by configuring the > PMU from the privileged mode (kernel space). > > by default rte_rdtsc() implementation uses portable > cntvct_el0 scheme. Application can choose the PMU based implementation with > CONFIG_RTE_ARM_EAL_RDTSC_USE_PMU > > Signed-off-by: Jerin Jacob <jerin.jacob at caviumnetworks.com>
Acked-by: Hemant Agrawal <hemant.agrawal at nxp.com>
