From mboxrd@z Thu Jan 1 00:00:00 1970 From: Xiao Yang Date: Tue, 17 Jul 2018 17:41:21 +0800 Subject: [LTP] Question about Cpus_allowed_list Message-ID: <5B4DB9C1.1040209@cn.fujitsu.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: ltp@lists.linux.it Hi, With Intel(R) Core(TM)2 Duo CPU E7500, running cpuset_hotplug_test.sh always got the following error: ------------------------------------------------------------------------------------- cpuset_hotplug 1 TFAIL: task's allowed list isn't expected.(Result: 0-3, Expect: 0-1) ------------------------------------------------------------------------------------- No matter what is the number of cpu processors from /proc/cpuinfo (specify 2 or 1 by offlining cpu), the Cpus_allowed_list from /proc//status is always 0-3. Simple steps to reproduce this issue: # /bin/cat /dev/zero > /dev/null 2>&1 & [1] 15079 # nproc (or cat /proc/cpuinfo | grep processor | wc -l) 2 # cat /proc/15079/status | grep Cpus_allowed_list Cpus_allowed_list: 0-3 We also tested cpuset_hotplug_test.sh with Core(TM) i3 CPU and Core(TM) i5 CPU, it showed the same Cpus_allowed_list as the number of cpu processors as expected. Is this a known issue on Core(TM)2 Duo CPU, should we use taskset command to change Cpus_allowed_list? Thanks, Xiao Yang