Note: This bug is displayed in read-only format because
the product is no longer active in Red Hat Bugzilla.
RHEL Engineering is moving the tracking of its product development work on RHEL 6 through RHEL 9 to Red Hat Jira (issues.redhat.com). If you're a Red Hat customer, please continue to file support cases via the Red Hat customer portal. If you're not, please head to the "RHEL project" in Red Hat Jira and file new tickets here. Individual Bugzilla bugs in the statuses "NEW", "ASSIGNED", and "POST" are being migrated throughout September 2023. Bugs of Red Hat partners with an assigned Engineering Partner Manager (EPM) are migrated in late September as per pre-agreed dates. Bugs against components "kernel", "kernel-rt", and "kpatch" are only migrated if still in "NEW" or "ASSIGNED". If you cannot log in to RH Jira, please consult article #7032570. That failing, please send an e-mail to the RH Jira admins at rh-issues@redhat.com to troubleshoot your issue as a user management inquiry. The email creates a ServiceNow ticket with Red Hat. Individual Bugzilla bugs that are migrated will be moved to status "CLOSED", resolution "MIGRATED", and set with "MigratedToJIRA" in "Keywords". The link to the successor Jira issue will be found under "Links", have a little "two-footprint" icon next to it, and direct you to the "RHEL project" in Red Hat Jira (issue links are of type "https://issues.redhat.com/browse/RHEL-XXXX", where "X" is a digit). This same link will be available in a blue banner at the top of the page informing you that that bug has been migrated.
`cgroup` values can now be correctly displayed for threads under a parent process by using "ps -o thcgr"
Previously, the "ps" command displayed only the control group (`cgroup`) of the parent process. Consequently, `cgroup` values of the threads under a parent process were identical to the `cgroup` value of the parent process. This update introduces a new option, "thcgr", to maintain compatibility with current `cgroup` listing. When the "thcgr" option is used, the correct individual `cgroup` values are displayed for threads under the parent process.
This needs to be forward-ported from RHEL6. The problem here is that the procps-ng-3.3.10 has a support for cgroups in the library and drops '/' cgroups. We need to avoid touching the library to keep the interface compatible and re-implement the filtering logic in order to stay consistent with the recent code.
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.
For information on the advisory, and where to find the updated
files, follow the link below.
If the solution does not work for you, open a new bug report.
https://rhn.redhat.com/errata/RHBA-2016-2447.html
Description of problem: ps is showing all threads in the same cgroup/cpuset when they are on different cgroup/cpuset. Version-Release number of selected component (if applicable): procps-ng-3.3.10-3.el7.x86_64 How reproducible: Always Steps to Reproduce: On a RHEL7 minimal install (I am using auditd just as an example of multi-thread app). 1. Create a cpuset: # cd /sys/fs/cgroup/cpuset # mkdir app # cd app/ # echo 0 > cpuset.cpus # echo 0 > cpuset.mems 3. select a multi-threaded proc (e.g auditd): # ps -eLo pid,lwp,comm,cgroup | grep audit 108 108 kauditd - 596 596 auditd 1:name=systemd:/system.slice/auditd.service 596 602 auditd 1:name=systemd:/system.slice/auditd.service 4. Insert the thread with the same pid/lwp in this new cgroup/cpuset: # echo 596 > tasks # cat tasks 596 5. List the threads showing its cgroup/cpuset: # ps -eLo pid,lwp,comm,cgroup | grep audit 108 108 kauditd - 596 596 auditd 2:cpuset:/app,1:name=systemd:/system.slice/auditd.service 596 602 auditd 2:cpuset:/app,1:name=systemd:/system.slice/auditd.service Actual results: ps shows all threads in the same cgroup/cpuset, but they are not in the same cgroup/cpuset. Expected results: ps showing the correct cgroup/cpuset for threads. Additional info: Stracing ps: It opens the proc/PID/ dir and checks the status of the proc. stat("/proc/596", {st_mode=S_IFDIR|0555, st_size=0, ...}) = 0 open("/proc/596/stat", O_RDONLY) = 6 read(6, "596 (auditd) S 1 596 596 0 -1 42"..., 2048) = 359 close(6) = 0 open("/proc/596/status", O_RDONLY) = 6 read(6, "Name:\tauditd\nState:\tS (sleeping)"..., 2048) = 1039 close(6) = 0 It reads the proc cgroup (but never the threads cgroup file): open("/proc/596/cgroup", O_RDONLY) = 6 read(6, "10:hugetlb:/\n9:perf_event:/\n8:bl"..., 131072) = 159 read(6, "", 130913) = 0 close(6) = 0 openat(AT_FDCWD, "/proc/596/task", O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC) = 6 getdents(6, /* 4 entries */, 32768) = 96 stat("/proc/596/task/596", {st_mode=S_IFDIR|0555, st_size=0, ...}) = 0 open("/proc/596/task/596/stat", O_RDONLY) = 7 read(7, "596 (auditd) S 1 596 596 0 -1 42"..., 1024) = 359 close(7) = 0 open("/proc/596/task/596/status", O_RDONLY) = 7 read(7, "Name:\tauditd\nState:\tS (sleeping)"..., 1024) = 1024 read(7, "t_switches:\t15\n", 1024) = 15 close(7) = 0 write(1, " 596 596 auditd 2:cp"..., 86) = 86 stat("/proc/596/task/602", {st_mode=S_IFDIR|0555, st_size=0, ...}) = 0 open("/proc/596/task/602/stat", O_RDONLY) = 7 read(7, "602 (auditd) S 1 596 596 0 -1 10"..., 2048) = 364 close(7) = 0 open("/proc/596/task/602/status", O_RDONLY) = 7 read(7, "Name:\tauditd\nState:\tS (sleeping)"..., 2048) = 1040 close(7) = 0 write(1, " 596 602 auditd 2:cp"..., 86) = 86 getdents(6, /* 0 entries */, 32768) = 0 Additional info 2: I opened a similar BUG Report for RHEL6 (BZ1284076), but ps behaves differently.