linux/kernel/sched/debug.c, branch v3.12.14

sched: Avoid throttle_cfs_rq() racing with period_timer stopping

2013-12-20T15:49:07Z

commit f9f9ffc237dd924f048204e8799da74f9ecf40cf upstream. throttle_cfs_rq() doesn't check to make sure that period_timer is running, and while update_curr/assign_cfs_runtime does, a concurrently running period_timer on another cpu could cancel itself between this cpu's update_curr and throttle_cfs_rq(). If there are no other cfs_rqs running in the tg to restart the timer, this causes the cfs_rq to be stranded forever. Fix this by calling __start_cfs_bandwidth() in throttle if the timer is inactive. (Also add some sched_debug lines for cfs_bandwidth.) Tested: make a run/sleep task in a cgroup, loop switching the cgroup between 1ms/100ms quota and unlimited, checking for timer_active=0 and throttled=1 as a failure. With the throttle_cfs_rq() change commented out this fails, with the full patch it passes. Signed-off-by: Ben Segall Signed-off-by: Peter Zijlstra Cc: pjt@google.com Link: http://lkml.kernel.org/r/20131016181632.22647.84174.stgit@sword-of-the-dawn.mtv.corp.google.com Signed-off-by: Ingo Molnar Cc: Chris J Arges Signed-off-by: Greg Kroah-Hartman

sched/debug: Take PID namespace into account

2013-09-12T17:14:16Z

Emmanuel reported that /proc/sched_debug didn't report the right PIDs when using namespaces, cure this. Reported-by: Emmanuel Deloget Signed-off-by: Peter Zijlstra Link: http://lkml.kernel.org/r/20130909110141.GM31370@twins.programming.kicks-ass.net Signed-off-by: Ingo Molnar

sched/debug: Remove CONFIG_FAIR_GROUP_SCHED mask

2013-06-28T11:17:17Z

Now that we are using runnable load avg in sched balance, we don't need to keep it under CONFIG_FAIR_GROUP_SCHED. Also align the code style to #ifdef instead of #if defined() and reorder the tg output info. Signed-off-by: Alex Shi Cc: pjt@google.com Cc: kamalesh@linux.vnet.ibm.com Cc: peterz@infradead.org Link: http://lkml.kernel.org/r/1372417835-4698-1-git-send-email-alex.shi@intel.com Signed-off-by: Ingo Molnar

sched/debug: Fix formatting of /proc//sched

2013-06-28T09:13:35Z

This patch alters format string's width, to align all statistics at par with the longest struct sched_statistic member name under /proc//sched. Signed-off-by: Kamalesh Babulal Cc: peterz@infradead.org Link: http://lkml.kernel.org/r/20130627165005.GA15583@linux.vnet.ibm.com Signed-off-by: Ingo Molnar

sched/debug: Add load-tracking statistics to task

2013-06-27T08:07:46Z

At present we print per-entity load-tracking statistics for cfs_rq of cgroups/runqueues. Given that per task statistics is maintained, it can be used to know the contribution made by the task to its parenting cfs_rq level. This patch adds per-task load-tracking statistics to /proc//sched. Signed-off-by: Kamalesh Babulal Signed-off-by: Peter Zijlstra Link: http://lkml.kernel.org/r/20130625080336.GA20175@linux.vnet.ibm.com Signed-off-by: Ingo Molnar

sched/tg: Use 'unsigned long' for load variable in task group

2013-06-27T08:07:40Z

Since tg->load_avg is smaller than tg->load_weight, we don't need a atomic64_t variable for load_avg in 32 bit machine. The same reason for cfs_rq->tg_load_contrib. The atomic_long_t/unsigned long variable type are more efficient and convenience for them. Signed-off-by: Alex Shi Tested-by: Vincent Guittot Signed-off-by: Peter Zijlstra Link: http://lkml.kernel.org/r/1371694737-29336-11-git-send-email-alex.shi@intel.com Signed-off-by: Ingo Molnar

sched: Change cfs_rq load avg to unsigned long

2013-06-27T08:07:38Z

Since the 'u64 runnable_load_avg, blocked_load_avg' in cfs_rq struct are smaller than 'unsigned long' cfs_rq->load.weight. We don't need u64 vaiables to describe them. unsigned long is more efficient and convenience. Signed-off-by: Alex Shi Reviewed-by: Paul Turner Tested-by: Vincent Guittot Signed-off-by: Peter Zijlstra Link: http://lkml.kernel.org/r/1371694737-29336-10-git-send-email-alex.shi@intel.com Signed-off-by: Ingo Molnar

Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2013-02-27T03:42:08Z

Pull scheduler fixes from Ingo Molnar. * 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: cputime: Use local_clock() for full dynticks cputime accounting cputime: Constify timeval_to_cputime(timeval) argument sched: Move RR_TIMESLICE from sysctl.h to rt.h sched: Fix /proc/sched_debug failure on very very large systems sched: Fix /proc/sched_stat failure on very very large systems sched/core: Remove the obsolete and unused nr_uninterruptible() function

sched: Fix /proc/sched_debug failure on very very large systems

2013-02-22T09:27:25Z

On systems with 4096 cores attemping to read /proc/sched_debug fails because we are trying to push all the data into a single kmalloc buffer. The issue is on these very large machines all the data will not fit in 4mb. A better solution is to not us the single_open mechanism but to provide our own seq_operations and treat each cpu as an individual record. The output should be identical to the previous version. Reported-by: Dave Jones Signed-off-by: Nathan Zimmer Cc: Peter Zijlstra ) [ Whitespace fixlet] [ Fix spello in comment] Signed-off-by: Andrew Morton Signed-off-by: Ingo Molnar

Merge branch 'for-3.9' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup

2013-02-20T17:16:21Z

Pull cgroup changes from Tejun Heo: "Nothing too drastic. - Removal of synchronize_rcu() from userland visible paths. - Various fixes and cleanups from Li. - cgroup_rightmost_descendant() added which will be used by cpuset changes (it will be a separate pull request)." * 'for-3.9' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: cgroup: fail if monitored file and event_control are in different cgroup cgroup: fix cgroup_rmdir() vs close(eventfd) race cpuset: fix cpuset_print_task_mems_allowed() vs rename() race cgroup: fix exit() vs rmdir() race cgroup: remove bogus comments in cgroup_diput() cgroup: remove synchronize_rcu() from cgroup_diput() cgroup: remove duplicate RCU free on struct cgroup sched: remove redundant NULL cgroup check in task_group_path() sched: split out css_online/css_offline from tg creation/destruction cgroup: initialize cgrp->dentry before css_alloc() cgroup: remove a NULL check in cgroup_exit() cgroup: fix bogus kernel warnings when cgroup_create() failed cgroup: remove synchronize_rcu() from rebind_subsystems() cgroup: remove synchronize_rcu() from cgroup_attach_{task|proc}() cgroup: use new hashtable implementation cgroups: fix cgroup_event_listener error handling cgroups: move cgroup_event_listener.c to tools/cgroup cgroup: implement cgroup_rightmost_descendant() cgroup: remove unused dummy cgroup_fork_callbacks()