How to read and interpret /dev/cpu_dma_latency?

Solution Verified - Updated -

Issue

  • Reading /dev/cpu_dma_latency from userspace / user mode is not clarified in kernel sources in 'Documentation/power/pm_qos_interface.txt'

  • reading /dev/cpu_dma_latency prints gibberish

# cat /dev/cpu_dma_latency
�5w

Environment

Red Hat Enterprise Linux 7

Subscriber exclusive content

A Red Hat subscription provides unlimited access to our knowledgebase of over 48,000 articles and solutions.

Current Customers and Partners

Log in for full access

Log In