GitHub pull request #2562 of commit b0667492e677b71531b3e1de523baa9eae69fda6, no merge conflicts.sha1origin/pr/2562/mergeghprbActualCommitb0667492e677b71531b3e1de523baa9eae69fda6ghprbActualCommitAuthorghprbActualCommitAuthorEmailghprbAuthorRepoGitUrlhttps://github.com/iovisor/bcc.gitghprbTriggerAuthorghprbTriggerAuthorEmailghprbTriggerAuthorLoginyonghong-songghprbTriggerAuthorLoginMention@yonghong-songghprbPullId2562ghprbTargetBranchmasterghprbSourceBranchyhs_devGIT_BRANCHyhs_devghprbPullAuthorEmailghprbPullAuthorLoginyonghong-songghprbPullAuthorLoginMention@yonghong-songghprbPullDescriptionGitHub pull request #2562 of commit b0667492e677b71531b3e1de523baa9eae69fda6, no merge conflicts.ghprbPullTitlesupport cgroup level tracing in trace.pyghprbPullLinkhttps://github.com/iovisor/bcc/pull/2562ghprbPullLongDescriptionThis patch added cgroup based filtering in trace.py.\r\n\r\nIf a cgroup path is specified by the user, one cgroup\r\narray map will be added to the program:\r\n```\r\n BPF_CGROUP_ARRAY(__cgroup, 1);\r\n```\r\nEach probe will have a filter like below:\r\n```\r\n if (__cgroup.check_current_task(0) <= 0) { return 0; }\r\n```\r\nto filter out any events not happening in the cgroup\r\nhierarchy as specified by the user.\r\n\r\nThe trace.py updated the `__cgroup` map with user provided\r\ncgroup path information before attaching bpf functions\r\nto events for probe function(s).\r\n\r\nAn example like below:\r\n```\r\n $ trace.py -v -c /sys/fs/cgroup/system.slice/workload.service \\r\n '__x64_sys_nanosleep' '__x64_sys_clone'\r\n PID TID COMM FUNC\r\n 3191578 3191583 BaseAgentEvents __x64_sys_nanosleep\r\n 3191578 3191579 FutureTimekeepr __x64_sys_clone\r\n 3191578 3191583 BaseAgentEvents __x64_sys_nanosleep\r\n 3191578 3191583 BaseAgentEvents __x64_sys_nanosleep\r\n```\r\nsince workload.service only contains one process 3191578.\r\n\r\nGoing up the hierarchy to system.slice will have more processes\r\nand hence more results:\r\n```\r\n $ trace.py -v -c /sys/fs/cgroup/system.slice \\r\n '__x64_sys_nanosleep' '__x64_sys_clone'\r\n PID TID COMM FUNC\r\n 591542 591677 dynoScribe __x64_sys_nanosleep\r\n 591610 591613 mcreplay2 __x64_sys_nanosleep\r\n 553252 553252 sleeperagent __x64_sys_nanosleep\r\n 591610 591613 mcreplay2 __x64_sys_nanosleep\r\n 553252 553252 sleeperagent __x64_sys_nanosleep\r\n```\r\nSigned-off-by: Yonghong Song <yhs@fb.com>ghprbCommentBody[buildbot, test this please]ghprbGhRepositoryiovisor/bccghprbCredentialsId6d3daf13-69b8-48b1-9c8f-ec5353264113false<a title="support cgroup level tracing in trace.py" href="https://github.com/iovisor/bcc/pull/2562">PR #2562</a>: support cgroup level tracin...#9711806277460664bcc-pr #9797false97804SUCCESS1571587186254https://buildbot.iovisor.org/jenkins/user/dalehamel/my-views/view/all/job/bcc-pr/97/git97https://buildbot.iovisor.org/jenkins/user/dalehamel/my-views/view/all/job/bcc-pr/label=fc25/97/97https://buildbot.iovisor.org/jenkins/user/dalehamel/my-views/view/all/job/bcc-pr/label=fc26/97/97https://buildbot.iovisor.org/jenkins/user/dalehamel/my-views/view/all/job/bcc-pr/label=fc27/97/97https://buildbot.iovisor.org/jenkins/user/dalehamel/my-views/view/all/job/bcc-pr/label=fc28/97/97https://buildbot.iovisor.org/jenkins/user/dalehamel/my-views/view/all/job/bcc-pr/label=ubuntu1604/97/97https://buildbot.iovisor.org/jenkins/user/dalehamel/my-views/view/all/job/bcc-pr/label=ubuntu1710/97/97https://buildbot.iovisor.org/jenkins/user/dalehamel/my-views/view/all/job/bcc-pr/label=ubuntu1804/97/