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2013-06-28sched/debug: Remove CONFIG_FAIR_GROUP_SCHED maskAlex Shi1-4/+6
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 <alex.shi@intel.com> 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 <mingo@kernel.org>
2013-06-28sched/debug: Fix formatting of /proc/<PID>/schedKamalesh Babulal1-8/+9
This patch alters format string's width, to align all statistics at par with the longest struct sched_statistic member name under /proc/<PID>/sched. Signed-off-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com> Cc: peterz@infradead.org Link: http://lkml.kernel.org/r/20130627165005.GA15583@linux.vnet.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-27sched: Fix typo in struct sched_avg member descriptionKamalesh Babulal1-1/+1
Remove extra 'for' from the description about member of struct sched_avg. Signed-off-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com> Cc: pjt@google.com Cc: peterz@infradead.org Link: http://lkml.kernel.org/r/20130627060409.GB18582@linux.vnet.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-27sched/fair: Fix typo describing flags in enqueue_entityKamalesh Babulal1-1/+1
Fix spelling of 'calling' in description of se flags in enqueue_entity(). Signed-off-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com> Cc: peterz@infradead.org Link: http://lkml.kernel.org/r/20130627055418.GA18582@linux.vnet.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-27sched/debug: Add load-tracking statistics to taskKamalesh Babulal1-0/+6
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/<PID>/sched. Signed-off-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20130625080336.GA20175@linux.vnet.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-27sched: Change get_rq_runnable_load() to static and inlineAlex Shi1-2/+2
Based-on-patch-by: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: Alex Shi <alex.shi@intel.com> Tested-by: Vincent Guittot <vincent.guittot@linaro.org> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1371694737-29336-14-git-send-email-alex.shi@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-27sched/tg: Remove tg.load_weightAlex Shi1-1/+0
Since no one use it. Signed-off-by: Alex Shi <alex.shi@intel.com> Reviewed-by: Paul Turner <pjt@google.com> Tested-by: Vincent Guittot <vincent.guittot@linaro.org> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1371694737-29336-13-git-send-email-alex.shi@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-27sched/cfs_rq: Change atomic64_t removed_load to atomic_long_tAlex Shi2-5/+8
Similar to runnable_load_avg, blocked_load_avg variable, long type is enough for removed_load in 64 bit or 32 bit machine. Then we avoid the expensive atomic64 operations on 32 bit machine. Signed-off-by: Alex Shi <alex.shi@intel.com> Reviewed-by: Paul Turner <pjt@google.com> Tested-by: Vincent Guittot <vincent.guittot@linaro.org> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1371694737-29336-12-git-send-email-alex.shi@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-27sched/tg: Use 'unsigned long' for load variable in task groupAlex Shi3-11/+11
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 <alex.shi@intel.com> Tested-by: Vincent Guittot <vincent.guittot@linaro.org> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1371694737-29336-11-git-send-email-alex.shi@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-27sched: Change cfs_rq load avg to unsigned longAlex Shi3-8/+5
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 <alex.shi@intel.com> Reviewed-by: Paul Turner <pjt@google.com> Tested-by: Vincent Guittot <vincent.guittot@linaro.org> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1371694737-29336-10-git-send-email-alex.shi@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-27sched: Consider runnable load average in move_tasks()Alex Shi1-9/+9
Aside from using runnable load average in background, move_tasks is also the key function in load balance. We need consider the runnable load average in it in order to make it an apple to apple load comparison. Morten had caught a div u64 bug on ARM, thanks! Thanks-to: Morten Rasmussen <morten.rasmussen@arm.com> Signed-off-by: Alex Shi <alex.shi@intel.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1371694737-29336-8-git-send-email-alex.shi@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-27sched: Compute runnable load avg in cpu_load and cpu_avg_load_per_taskAlex Shi2-4/+18
They are the base values in load balance, update them with rq runnable load average, then the load balance will consider runnable load avg naturally. We also try to include the blocked_load_avg as cpu load in balancing, but that cause kbuild performance drop 6% on every Intel machine, and aim7/oltp drop on some of 4 CPU sockets machines. Or only add blocked_load_avg into get_rq_runable_load, hackbench still drop a little on NHM EX. Signed-off-by: Alex Shi <alex.shi@intel.com> Reviewed-by: Gu Zheng <guz.fnst@cn.fujitsu.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1371694737-29336-7-git-send-email-alex.shi@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-27sched: Update cpu load after task_tickAlex Shi1-1/+1
To get the latest runnable info, we need do this cpuload update after task_tick. Signed-off-by: Alex Shi <alex.shi@intel.com> Reviewed-by: Paul Turner <pjt@google.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1371694737-29336-6-git-send-email-alex.shi@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-27sched: Fix sleep time double accounting in enqueue entityAlex Shi1-1/+7
The woken migrated task will __synchronize_entity_decay(se); in migrate_task_rq_fair, then it needs to set `se->avg.last_runnable_update -= (-se->avg.decay_count) << 20' before update_entity_load_avg, in order to avoid sleep time is updated twice for se.avg.load_avg_contrib in both __syncchronize and update_entity_load_avg. However if the sleeping task is woken up from the same cpu, it miss the last_runnable_update before update_entity_load_avg(se, 0, 1), then the sleep time was used twice in both functions. So we need to remove the double sleep time accounting. Paul also contributed some code comments in this commit. Signed-off-by: Alex Shi <alex.shi@intel.com> Reviewed-by: Paul Turner <pjt@google.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1371694737-29336-5-git-send-email-alex.shi@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-27sched: Set an initial value of runnable avg for new forked taskAlex Shi3-4/+28
We need to initialize the se.avg.{decay_count, load_avg_contrib} for a new forked task. Otherwise random values of above variables cause a mess when a new task is enqueued: enqueue_task_fair enqueue_entity enqueue_entity_load_avg and make fork balancing imbalance due to incorrect load_avg_contrib. Further more, Morten Rasmussen notice some tasks were not launched at once after created. So Paul and Peter suggest giving a start value for new task runnable avg time same as sched_slice(). PeterZ said: > So the 'problem' is that our running avg is a 'floating' average; ie. it > decays with time. Now we have to guess about the future of our newly > spawned task -- something that is nigh impossible seeing these CPU > vendors keep refusing to implement the crystal ball instruction. > > So there's two asymptotic cases we want to deal well with; 1) the case > where the newly spawned program will be 'nearly' idle for its lifetime; > and 2) the case where its cpu-bound. > > Since we have to guess, we'll go for worst case and assume its > cpu-bound; now we don't want to make the avg so heavy adjusting to the > near-idle case takes forever. We want to be able to quickly adjust and > lower our running avg. > > Now we also don't want to make our avg too light, such that it gets > decremented just for the new task not having had a chance to run yet -- > even if when it would run, it would be more cpu-bound than not. > > So what we do is we make the initial avg of the same duration as that we > guess it takes to run each task on the system at least once -- aka > sched_slice(). > > Of course we can defeat this with wakeup/fork bombs, but in the 'normal' > case it should be good enough. Paul also contributed most of the code comments in this commit. Signed-off-by: Alex Shi <alex.shi@intel.com> Reviewed-by: Gu Zheng <guz.fnst@cn.fujitsu.com> Reviewed-by: Paul Turner <pjt@google.com> [peterz; added explanation of sched_slice() usage] Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1371694737-29336-4-git-send-email-alex.shi@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-27sched: Move a few runnable tg variables into CONFIG_SMPAlex Shi1-0/+2
The following 2 variables are only used under CONFIG_SMP, so its better to move their definiation into CONFIG_SMP too. atomic64_t load_avg; atomic_t runnable_avg; Signed-off-by: Alex Shi <alex.shi@intel.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1371694737-29336-3-git-send-email-alex.shi@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-27Revert "sched: Introduce temporary FAIR_GROUP_SCHED dependency for ↵Alex Shi4-42/+8
load-tracking" Remove CONFIG_FAIR_GROUP_SCHED that covers the runnable info, then we can use runnable load variables. Also remove 2 CONFIG_FAIR_GROUP_SCHED setting which is not in reverted patch(introduced in 9ee474f), but also need to revert. Signed-off-by: Alex Shi <alex.shi@intel.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/51CA76A3.3050207@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-19sched: Don't mix use of typedef ctl_table and struct ctl_tableJoe Perches1-1/+1
Just use struct ctl_table. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1371063336.2069.22.camel@joe-AO722 Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-19sched: Remove WARN_ON(!sd) from init_sched_groups_power()Viresh Kumar1-1/+1
sd can't be NULL in init_sched_groups_power() and so checking it for NULL isn't useful. In case it is required, then also we need to rearrange the code a bit as we already accessed invalid pointer sd to get sg: sg = sd->groups. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/2bbe633cd74b431c05253a8ce61fdfd5066a531b.1370948150.git.viresh.kumar@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-19sched: Fix memory leakage in build_sched_groups()Viresh Kumar1-2/+2
In build_sched_groups() we don't need to call get_group() for cpus which are already covered in previous iterations. Calling get_group() would mark the group used and eventually leak it since we wouldn't connect it and not find it again to free it. This will happen only in cases where sg->cpumask contained more than one cpu (For any topology level). This patch would free sg's memory for all cpus leaving the group leader as the group isn't marked used now. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/7a61e955abdcbb1dfa9fe493f11a5ec53a11ddd3.1370948150.git.viresh.kumar@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-19sched: Use cached value of span instead of calling sched_domain_span()Viresh Kumar1-1/+1
In the beginning of build_sched_groups() we called sched_domain_span() and cached its return value in span. Few statements later we are calling it again to get the same pointer. Lets use the cached value instead as it hasn't changed in between. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/834ecd507071ad88aff039352dbc7e063dd996a7.1370948150.git.viresh.kumar@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-19sched: Create for_each_sd_topology()Viresh Kumar1-3/+6
For loop for traversing sched_domain_topology was used at multiple placed in core.c. This patch removes code redundancy by creating for_each_sd_topology(). Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/e0e04542f54e9464bd9da54f5ccfe62ec6c4c0bc.1370861520.git.viresh.kumar@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-19sched: Don't set sd->child to NULL when it is already NULLViresh Kumar1-1/+1
Memory for sd is allocated with kzalloc_node() which will initialize its fields with zero. In build_sched_domain() we are setting sd->child to child even if child is NULL, which isn't required. Lets do it only if child isn't NULL. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/f4753a1730051341003ad2ad29a3229c7356678e.1370861520.git.viresh.kumar@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-19sched: Don't initialize alloc_state in build_sched_domains()Viresh Kumar1-1/+1
alloc_state will be overwritten by __visit_domain_allocation_hell() and so we don't actually need to initialize alloc_state. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/df57734a075cc5ad130e1ae498702e24f2529ab8.1370861520.git.viresh.kumar@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-19sched: Optimize build_sched_domains() for saving first SD node for a cpuViresh Kumar1-5/+2
We are saving first scheduling domain for a cpu in build_sched_domains() by iterating over the nested sd->child list. We don't actually need to do it this way. tl will be equal to sched_domain_topology for the first iteration and so we can set *per_cpu_ptr(d.sd, i) based on that. So, save pointer to first SD while running the iteration loop over tl's. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/fc473527cbc4dfa0b8eeef2a59db74684eb59a83.1370436120.git.viresh.kumar@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-19sched: Remove unused params of build_sched_domain()Viresh Kumar1-4/+3
build_sched_domain() never uses parameter struct s_data *d and so passing it is useless. Remove it. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/545e0b4536166a15b4475abcafe5ed0db4ad4a2c.1370436120.git.viresh.kumar@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-19sched: Rename sched.c as sched/core.c in comments and DocumentationViresh Kumar21-26/+27
Most of the stuff from kernel/sched.c was moved to kernel/sched/core.c long time back and the comments/Documentation never got updated. I figured it out when I was going through sched-domains.txt and so thought of fixing it globally. I haven't crossed check if the stuff that is referenced in sched/core.c by all these files is still present and hasn't changed as that wasn't the motive behind this patch. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/cdff76a265326ab8d71922a1db5be599f20aad45.1370329560.git.viresh.kumar@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-19sched: Femove the useless declaration in kernel/sched/fair.cMichael Wang1-4/+0
default_cfs_period(), do_sched_cfs_period_timer(), do_sched_cfs_slack_timer() already defined previously, no need to declare again. Signed-off-by: Michael Wang <wangyun@linux.vnet.ibm.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/51AD8808.7020608@linux.vnet.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-19sched: Refine the code in unthrottle_cfs_rq()Michael Wang1-1/+1
Directly use rq to save some code. Signed-off-by: Michael Wang <wangyun@linux.vnet.ibm.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/51AD87EB.1070605@linux.vnet.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-19sched/rt: Simplify pull_rt_task() logic and remove .leaf_rt_rq_listKirill Tkhai2-67/+16
[ Peter, this is based off of some of my work, I ran it though a few tests and it passed. I also reviewed it, and added my SOB as I am somewhat a co-author to it. ] Based on the patch by Steven Rostedt from previous year: https://lkml.org/lkml/2012/4/18/517 1)Simplify pull_rt_task() logic: search in pushable tasks of dest runqueue. The only pullable tasks are the tasks which are pushable in their local rq, and no others. 2)Remove .leaf_rt_rq_list member of struct rt_rq and functions connected with it: nobody uses it since now. Signed-off-by: Kirill Tkhai <tkhai@yandex.ru> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/287571370557898@web7d.yandex.ru Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-19Merge branch 'sched/urgent' into sched/coreIngo Molnar2751-44689/+126641
Merge in fixes before applying ongoing new work. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-19tracing/context-tracking: Add preempt_schedule_context() for tracingSteven Rostedt2-1/+57
Dave Jones hit the following bug report: =============================== [ INFO: suspicious RCU usage. ] 3.10.0-rc2+ #1 Not tainted ------------------------------- include/linux/rcupdate.h:771 rcu_read_lock() used illegally while idle! other info that might help us debug this: RCU used illegally from idle CPU! rcu_scheduler_active = 1, debug_locks = 0 RCU used illegally from extended quiescent state! 2 locks held by cc1/63645: #0: (&rq->lock){-.-.-.}, at: [<ffffffff816b39fd>] __schedule+0xed/0x9b0 #1: (rcu_read_lock){.+.+..}, at: [<ffffffff8109d645>] cpuacct_charge+0x5/0x1f0 CPU: 1 PID: 63645 Comm: cc1 Not tainted 3.10.0-rc2+ #1 [loadavg: 40.57 27.55 13.39 25/277 64369] Hardware name: Gigabyte Technology Co., Ltd. GA-MA78GM-S2H/GA-MA78GM-S2H, BIOS F12a 04/23/2010 0000000000000000 ffff88010f78fcf8 ffffffff816ae383 ffff88010f78fd28 ffffffff810b698d ffff88011c092548 000000000023d073 ffff88011c092500 0000000000000001 ffff88010f78fd60 ffffffff8109d7c5 ffffffff8109d645 Call Trace: [<ffffffff816ae383>] dump_stack+0x19/0x1b [<ffffffff810b698d>] lockdep_rcu_suspicious+0xfd/0x130 [<ffffffff8109d7c5>] cpuacct_charge+0x185/0x1f0 [<ffffffff8109d645>] ? cpuacct_charge+0x5/0x1f0 [<ffffffff8108dffc>] update_curr+0xec/0x240 [<ffffffff8108f528>] put_prev_task_fair+0x228/0x480 [<ffffffff816b3a71>] __schedule+0x161/0x9b0 [<ffffffff816b4721>] preempt_schedule+0x51/0x80 [<ffffffff816b4800>] ? __cond_resched_softirq+0x60/0x60 [<ffffffff816b6824>] ? retint_careful+0x12/0x2e [<ffffffff810ff3cc>] ftrace_ops_control_func+0x1dc/0x210 [<ffffffff816be280>] ftrace_call+0x5/0x2f [<ffffffff816b681d>] ? retint_careful+0xb/0x2e [<ffffffff816b4805>] ? schedule_user+0x5/0x70 [<ffffffff816b4805>] ? schedule_user+0x5/0x70 [<ffffffff816b6824>] ? retint_careful+0x12/0x2e ------------[ cut here ]------------ What happened was that the function tracer traced the schedule_user() code that tells RCU that the system is coming back from userspace, and to add the CPU back to the RCU monitoring. Because the function tracer does a preempt_disable/enable_notrace() calls the preempt_enable_notrace() checks the NEED_RESCHED flag. If it is set, then preempt_schedule() is called. But this is called before the user_exit() function can inform the kernel that the CPU is no longer in user mode and needs to be accounted for by RCU. The fix is to create a new preempt_schedule_context() that checks if the kernel is still in user mode and if so to switch it to kernel mode before calling schedule. It also switches back to user mode coming back from schedule in need be. The only user of this currently is the preempt_enable_notrace(), which is only used by the tracing subsystem. Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1369423420.6828.226.camel@gandalf.local.home Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-19sched: Fix clear NOHZ_BALANCE_KICKVincent Guittot1-4/+17
I have faced a sequence where the Idle Load Balance was sometime not triggered for a while on my platform, in the following scenario: CPU 0 and CPU 1 are running tasks and CPU 2 is idle CPU 1 kicks the Idle Load Balance CPU 1 selects CPU 2 as the new Idle Load Balancer CPU 2 sets NOHZ_BALANCE_KICK for CPU 2 CPU 2 sends a reschedule IPI to CPU 2 While CPU 3 wakes up, CPU 0 or CPU 1 migrates a waking up task A on CPU 2 CPU 2 finally wakes up, runs task A and discards the Idle Load Balance task A quickly goes back to sleep (before a tick occurs on CPU 2) CPU 2 goes back to idle with NOHZ_BALANCE_KICK set Whenever CPU 2 will be selected as the ILB, no reschedule IPI will be sent because NOHZ_BALANCE_KICK is already set and no Idle Load Balance will be performed. We must wait for the sched softirq to be raised on CPU 2 thanks to another part the kernel to come back to clear NOHZ_BALANCE_KICK. The proposed solution clears NOHZ_BALANCE_KICK in schedule_ipi if we can't raise the sched_softirq for the Idle Load Balance. Change since V1: - move the clear of NOHZ_BALANCE_KICK in got_nohz_idle_kick if the ILB can't run on this CPU (as suggested by Peter) Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1370419991-13870-1-git-send-email-vincent.guittot@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-05-31sched/x86: Construct all sibling maps if smtAndrew Jones1-4/+4
Commit 316ad248307fb ("sched/x86: Rewrite set_cpu_sibling_map()") broke the construction of sibling maps, which also broke the booted_cores accounting. Before the rewrite, if smt was present, then each map was updated for each smt sibling. After the rewrite only cpu_sibling_mask gets updated, as the llc and core maps depend on 'has_mc = x86_max_cores > 1' instead. This leads to problems with topologies like the following (qemu -smp sockets=2,cores=1,threads=2) processor : 0 physical id : 0 siblings : 1 <= should be 2 core id : 0 cpu cores : 1 processor : 1 physical id : 0 siblings : 1 <= should be 2 core id : 0 cpu cores : 0 <= should be 1 processor : 2 physical id : 1 siblings : 1 <= should be 2 core id : 0 cpu cores : 1 processor : 3 physical id : 1 siblings : 1 <= should be 2 core id : 0 cpu cores : 0 <= should be 1 This patch restores the former construction by defining has_mc as (has_smt || x86_max_cores > 1). This should be fine as there were no (has_smt && !has_mc) conditions in the context. Aso rename has_mc to has_mp now that it's not just for cores. Signed-off-by: Andrew Jones <drjones@redhat.com> Acked-by: Peter Zijlstra <peterz@infradead.org> Cc: a.p.zijlstra@chello.nl Cc: fenghua.yu@intel.com Link: http://lkml.kernel.org/r/1369831695-11970-1-git-send-email-drjones@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-05-31sched/fair: Remove unused variable from expire_cfs_rq_runtime()Kamalesh Babulal1-1/+0
Commit 78becc2709 ("sched: Use an accessor to read the rq clock") introduces rq_clock(), which obsoletes the use of the "rq" variable in expire_cfs_rq_runtime() and triggers this build warning: kernel/sched/fair.c: In function 'expire_cfs_rq_runtime': kernel/sched/fair.c:2159:13: warning: unused variable 'rq' [-Wunused-variable] Signed-off-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Acked-by: Paul Turner <pjt@google.com> Cc: peterz@infradead.org Link: http://lkml.kernel.org/r/1369904660-14169-1-git-send-email-kamalesh@linux.vnet.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-05-30Merge branch 'mn10300' (mn10300 fixes from David Howells)Linus Torvalds3-13/+9
Merge mn10300 fixes from David Howells. * emailed patches from David Howells <dhowells@redhat.com>: MN10300: Need pci_iomap() and __pci_ioport_map() defining MN10300: ASB2305's PCI code needs the definition of XIRQ1 MN10300: Enable IRQs more in system call exit work path MN10300: Fix ret_from_kernel_thread
2013-05-30MN10300: Need pci_iomap() and __pci_ioport_map() definingDavid Howells1-0/+2
Include the generic definitions of pci_iomap() and __pci_ioport_map() otherwise we can get errors like: lib/pci_iomap.c: In function 'pci_iomap': lib/pci_iomap.c:37: error: implicit declaration of function '__pci_ioport_map' lib/pci_iomap.c:37: warning: return makes pointer from integer without a cast and: drivers/pci/quirks.c: In function 'disable_igfx_irq': drivers/pci/quirks.c:2893: error: implicit declaration of function 'pci_iomap' drivers/pci/quirks.c:2893: warning: initialization makes pointer from integer without a cast drivers/pci/quirks.c: In function 'reset_ivb_igd': drivers/pci/quirks.c:3133: warning: assignment makes pointer from integer without a cast Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Ken Cox <jkc@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-05-30MN10300: ASB2305's PCI code needs the definition of XIRQ1David Howells1-0/+1
The code for PCI in the ASB2305 needs the definition of XIRQ1 from proc/irq.h otherwise the following error appears: arch/mn10300/unit-asb2305/pci.c: In function 'unit_pci_init': arch/mn10300/unit-asb2305/pci.c:481: error: 'XIRQ1' undeclared (first use in this function) arch/mn10300/unit-asb2305/pci.c:481: error: (Each undeclared identifier is reported only once arch/mn10300/unit-asb2305/pci.c:481: error: for each function it appears in.) Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Ken Cox <jkc@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-05-30MN10300: Enable IRQs more in system call exit work pathDavid Howells1-13/+5
Enable IRQs when calling schedule() for TIF_NEED_RESCHED and do_notify_resume(). If interrupts are enabled during do_notify_resume(), a warning can be seen (see lower down). Whilst we're at it, resume_userspace can be made local to entry.S as it is not called outside of there and it can be merged with the part of work_resched that occurs after schedule() is called. WARNING: at kernel/softirq.c:160 local_bh_enable+0x42/0xa0() Call Trace: local_bh_enable+0x42/0xa0 unix_release_sock+0x86/0x23c unix_release+0x20/0x28 sock_release+0x17/0x88 sock_close+0x20/0x28 __fput+0xc9/0x1fc ____fput+0xb/0x10 task_work_run+0x64/0x78 do_notify_resume+0x53d/0x544 work_notifysig+0xa/0xc Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Ken Cox <jkc@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-05-30MN10300: Fix ret_from_kernel_threadDavid Howells1-0/+1
ret_from_kernel_thread needs to set A2 to the thread_info pointer before jumping to syscall_exit. Without this, we never correctly start userspace. This was caused by the rejuggling of the fork/exec paths in commit ddf23e87a804 ("mn10300: switch to saner kernel_execve() semantics") Reported-by: Ken Cox <jkc@redhat.com> Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Ken Cox <jkc@redhat.com> Acked-by: Al Viro <viro@ZenIV.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-05-30Merge tag 'pinctrl-fixes-v3.10-3' of ↵Linus Torvalds9-11/+323
git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl Pull pin-control fixes from Linus Walleij: - Six patches fixing up the suspend/resume and wakeup handling of the Samsung and Exynos drivers. - Errorpath fixes for four different drivers. All on the probe() errorpath. - Make the debugfs code for pin config take the right mutex. * tag 'pinctrl-fixes-v3.10-3' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl: pinctrl: pinconf: take the right mutex pinctrl: sunxi: fix error return code in sunxi_pinctrl_probe() pinctrl: exynos: Handle suspend/resume of GPIO EINT registers pinctrl: samsung: Allow per-bank SoC-specific private data pinctrl: samsung: Add support for SoC-specific suspend/resume callbacks pinctrl: Don't override the error code in probe error handling ARM: EXYNOS: Fix EINT wake-up mask configuration when pinctrl is used pinctrl: exynos: Add support for set_irq_wake of wake-up EINTs pinctrl: samsung: fix suspend/resume functionality
2013-05-29Merge tag 'fixes-for-linus' of ↵Linus Torvalds7-17/+107
git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc Pull ARM Exynos fixes from Olof Johansson: "Here's a shorter set of fixes for 3.10, all for Samsung Exynos platforms. It also includes a defconfig update so that exynos_defconfig provides a meaningful set of drivers to boot an unmodified kernel on the Samsung ARM-based Chromebooks." * tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: ARM: exynos: defconfig update ARM: SAMSUNG: Add names to fimd0 IRQ resources ARM: EXYNOS: fix software reset logic for EXYNOS5440 SOC ARM: EXYNOS: Fix support of Exynos4210 rev0 SoC ARM: dts: Enabling samsung-usb2phy driver for exynos5250
2013-05-29ARM: exynos: defconfig updateOlof Johansson1-8/+46
This turns on a number of configs that are useful on the Chromebook, but also good to have on in general: * USB host and MMC drivers(!) * I2C GPIO arbitration driver * CYAPA trackpad driver * simplefb * CROS EC and keyboard drivers * S5M8767 driver * MAX77686 drivers * MAX8997 driver * DEVTMPFS + mount * DM_CRYPT (as module) * CRYPTOLOOP * HIGHMEM * PRINTK timestamps This also turns off DEBUG_LL, and switches the hardcoded Samsung lowlevel uart to uart 3 (which is only used to show the "uncompressing kernel" message at boot, it seems). Signed-off-by: Olof Johansson <olof@lixom.net> Reviewed-by: Doug Anderson <dianders@chromium.org> Tested-by: Tushar Behera <tushar.behera@linaro.org> Acked-by: Kukjin Kim <kgene.kim@samsung.com>
2013-05-28Merge branch 'drm-fixes' of git://people.freedesktop.org/~airlied/linuxLinus Torvalds23-164/+163
Pull drm fixes from Dave Airlie: "This is mostly exynos and intel fixes, along with some vblank patches I lost from Rob a few months ago that make wayland work better on lots of GPUs, also a qxl kconfig fix." * 'drm-fixes' of git://people.freedesktop.org/~airlied/linux: (22 commits) qxl: fix Kconfig deps - select FB_DEFERRED_IO drm/exynos: replace request_threaded_irq with devm function drm/exynos: remove unnecessary devm_kfree drm/exynos: fix build warnings from ipp fimc drm/exynos: cleanup device pointer usages drm/exynos: wait for the completion of pending page flip drm/exynos: use drm_send_vblank_event() helper drm/i915: avoid premature DP AUX timeouts drm/i915: avoid premature timeouts in __wait_seqno() drm/i915: use msecs_to_jiffies_timeout instead of open coding the same drm/i915: add msecs_to_jiffies_timeout to guarantee minimum duration drm/i915: force full modeset if the connector is in DPMS OFF mode drm/exynos: page flip fixes drm/exynos: exynos_hdmi: Pass correct pointer to free_irq() drm/exynos: exynos_drm_ipp: Fix incorrect usage of IS_ERR_OR_NULL drm/exynos: exynos_drm_fbdev: Fix incorrect usage of IS_ERR_OR_NULL drm/imx: use drm_send_vblank_event() helper drm/shmob: use drm_send_vblank_event() helper drm/radeon: use drm_send_vblank_event() helper drm/nouveau: use drm_send_vblank_event() helper ...
2013-05-28Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6Linus Torvalds3-4/+4
Pull crypto fixes from Herbert Xu: "This push fixes a crash in the new sha256_ssse3 driver as well as a DMA setup/teardown bug in caam" * git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: crypto: sha256_ssse3 - fix stack corruption with SSSE3 and AVX implementations crypto: caam - fix inconsistent assoc dma mapping direction
2013-05-28Merge branch 'for-3.10' of git://git.samba.org/sfrench/cifs-2.6Linus Torvalds4-83/+88
Pull CIFS fixes from Steve French: "Fixes for a couple of DFS problems, a problem with extended security negotiation and two other small cifs fixes" * 'for-3.10' of git://git.samba.org/sfrench/cifs-2.6: cifs: fix composing of mount options for DFS referrals cifs: stop printing the unc= option in /proc/mounts cifs: fix error handling when calling cifs_parse_devname cifs: allow sec=none mounts to work against servers that don't support extended security cifs: fix potential buffer overrun when composing a new options string cifs: only set ops for inodes in I_NEW state
2013-05-28Merge tag 'trace-fixes-v3.10-rc3' of ↵Linus Torvalds2-2/+10
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing fixes from Steven Rostedt: "Two more fixes: The first one was reported by Mauro Carvalho Chehab, where if a poll() is done against a trace buffer for a CPU that has never been online, it will crash the kernel, as buffers are only created when a CPU comes on line, but the trace files are for all possible CPUs. This fix is to check if the buffer was allocated and if not return -EINVAL. That was the simple fix, the real fix is a bit more complex and not for a -rc release. We could have the files created when the CPUs come online. That would require some design changes. The second one was reported by Peter Zijlstra. If the kernel command line has ftrace=nop, it will lock up the system on boot up. This is because the new design for 3.10 has the nop tracer bootstrap the tracing subsystem. When ftrace=<trace> is defined, when a that tracer is registered, it starts the tracing, but uses the nop tracer to clear things out. What happened here was that ftrace=nop caused the registering of nop to start it and use nop before it was initialized. The only thing nop needs to have done to initialize it is to have the tracer point its current_tracer structure member to the nop tracer. Doing that before registering the nop tracer makes everything work." * tag 'trace-fixes-v3.10-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: ring-buffer: Do not poll non allocated cpu buffers tracing: Fix crash when ftrace=nop on the kernel command line
2013-05-28Merge branch 'for-linus' of ↵Linus Torvalds14-699/+2076
git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k Pull m68k fixes from Geert Uytterhoeven: - futex support that I had missed before, - A long-overdue update of the m68k defconfigs. * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k: m68k: Update defconfigs for v3.9 m68k: implement futex.h to support userspace robust futexes and PI mutexes
2013-05-28Merge branch 'next' of git://git.monstr.eu/linux-2.6-microblazeLinus Torvalds3-5/+5
Pull microblaze fixes from Michal Simek: "One patch fix futex support and my patches fix warnings which were reported by Geert's regression testing" * 'next' of git://git.monstr.eu/linux-2.6-microblaze: microblaze: Reversed logic in futex cmpxchg microblaze: Use proper casting for inb/inw/inl in io.h microblaze: Initialize temp variable to remove compilation warning
2013-05-28ring-buffer: Do not poll non allocated cpu buffersSteven Rostedt (Red Hat)1-0/+3
The tracing infrastructure sets up for possible CPUs, but it uses the ring buffer polling, it is possible to call the ring buffer polling code with a CPU that hasn't been allocated. This will cause a kernel oops when it access a ring buffer cpu buffer that is part of the possible cpus but hasn't been allocated yet as the CPU has never been online. Reported-by: Mauro Carvalho Chehab <mchehab@redhat.com> Tested-by: Mauro Carvalho Chehab <mchehab@redhat.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>