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2016-05-05sched/core: Move task_rq_lock() out of linePeter Zijlstra
Its a rather large function, inline doesn't seems to make much sense: $ size defconfig-build/kernel/sched/core.o{.orig,} text data bss dec hex filename 56533 21037 2320 79890 13812 defconfig-build/kernel/sched/core.o.orig 55733 21037 2320 79090 134f2 defconfig-build/kernel/sched/core.o The 'perf bench sched messaging' micro-benchmark shows a visible improvement of 4-5%: $ for i in /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor ; do echo performance > $i ; done $ perf stat --null --repeat 25 -- perf bench sched messaging -g 40 -l 5000 pre: 4.582798193 seconds time elapsed ( +- 1.41% ) 4.733374877 seconds time elapsed ( +- 2.10% ) 4.560955136 seconds time elapsed ( +- 1.43% ) 4.631062303 seconds time elapsed ( +- 1.40% ) post: 4.364765213 seconds time elapsed ( +- 0.91% ) 4.454442734 seconds time elapsed ( +- 1.18% ) 4.448893817 seconds time elapsed ( +- 1.41% ) 4.424346872 seconds time elapsed ( +- 0.97% ) Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-05-05Merge branch 'sched/urgent' into sched/core, to pick up fixes before ↵Ingo Molnar
applying new changes Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-28sched/core: Add switch_mm_irqs_off() and use it in the schedulerAndy Lutomirski
By default, this is the same thing as switch_mm(). x86 will override it as an optimization. Signed-off-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Borislav Petkov <bp@suse.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/df401df47bdd6be3e389c6f1e3f5310d70e81b2c.1461688545.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-28sched/cpufreq: Optimize cpufreq update kicker to avoid update multiple timesWanpeng Li
Sometimes delta_exec is 0 due to update_curr() is called multiple times, this is captured by: u64 delta_exec = rq_clock_task(rq) - curr->se.exec_start; This patch optimizes the cpufreq update kicker by bailing out when nothing changed, it will benefit the upcoming schedutil, since otherwise it will (over)react to the special util/max combination. Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1461316044-9520-1-git-send-email-wanpeng.li@hotmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-28nohz/full, sched/rt: Fix missed tick-reenabling bug in sched_can_stop_tick()Peter Zijlstra
Chris Metcalf reported a that sched_can_stop_tick() sometimes fails to re-enable the tick. His observed problem is that rq->cfs.nr_running can be 1 even though there are multiple runnable CFS tasks. This happens in the cgroup case, in which case cfs.nr_running is the number of runnable entities for that level. If there is a single runnable cgroup (which can have an arbitrary number of runnable child entries itself) rq->cfs.nr_running will be 1. However, looking at that function I think there's more problems with it. It seems to assume that if there's FIFO tasks, those will run. This is incorrect. The FIFO task can have a lower prio than an RR task, in which case the RR task will run. So the whole fifo_nr_running test seems misplaced, it should go after the rr_nr_running tests. That is, only if !rr_nr_running, can we use fifo_nr_running like this. Reported-by: Chris Metcalf <cmetcalf@mellanox.com> Tested-by: Chris Metcalf <cmetcalf@mellanox.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Christoph Lameter <cl@linux.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Luiz Capitulino <lcapitulino@redhat.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: Viresh Kumar <viresh.kumar@linaro.org> Cc: Wanpeng Li <kernellwp@gmail.com> Fixes: 76d92ac305f2 ("sched: Migrate sched to use new tick dependency mask model") Link: http://lkml.kernel.org/r/20160421160315.GK24771@twins.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-23Merge branches 'perf-urgent-for-linus', 'smp-urgent-for-linus' and ↵Linus Torvalds
'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf, cpu hotplug and timer fixes from Ingo Molnar: "perf: - A single tooling fix for a user-triggerable segfault. CPU hotplug: - Fix a CPU hotplug corner case regression, introduced by the recent hotplug rework timers: - Fix a boot hang in the ARM based Tango SoC clocksource driver" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf intel-pt: Fix segfault tracing transactions * 'smp-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: cpu/hotplug: Fix rollback during error-out in __cpu_disable() * 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: clocksource/drivers/tango-xtal: Fix boot hang due to incorrect test
2016-04-23Merge branch 'locking-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull locking fixes from Ingo Molnar: "Misc fixes: pvqspinlocks: - an instrumentation fix futexes: - preempt-count vs pagefault_disable decouple corner case fix - futex requeue plist race window fix - futex UNLOCK_PI transaction fix for a corner case" * 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: asm-generic/futex: Re-enable preemption in futex_atomic_cmpxchg_inatomic() futex: Acknowledge a new waiter in counter before plist futex: Handle unlock_pi race gracefully locking/pvqspinlock: Fix division by zero in qstat_read()
2016-04-23Merge branch 'irq-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq fixes from Ingo Molnar: "A core irq affinity masks related fix and a MIPS irqchip driver fix" * 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: irqchip/mips-gic: Don't overrun pcpu_masks array genirq: Dont allow affinity mask to be updated on IPIs
2016-04-23sched/deadline: Fix a bug in dl_overflow()Xunlei Pang
I got a minus(very big) dl_b->total_bw during my deadline tests. # grep dl /proc/sched_debug dl_rq[0]: .dl_nr_running : 0 .dl_bw->bw : 996147 .dl_bw->total_bw : -222297900 Something unusual must have happened. After some digging, I finally noticed that when changing a deadline task to normal(cfs), and changing it back to deadline immediately, after it died, we will got the wrong dl_bw->total_bw. The root cause is in dl_overflow(), it has: if (new_bw == p->dl.dl_bw) return 0; 1) When a deadline task is changed to !deadline task, it will start dl timer in switched_from_dl(), and retain previous deadline parameter till the timer expires. 2) If we change it back to deadline with the same bandwidth parameter before the timer expires, as it keeps the old bandwidth although it is not a deadline task. dl_overflow() simply returns success without updating the right data, and got the wrong dl_bw->total_bw. The solution is simple, if @p is not deadline, don't return. Signed-off-by: Xunlei Pang <xlpang@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Juri Lelli <juri.lelli@arm.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1460636368-1993-1-git-send-email-xlpang@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-23sched/fair: Optimize !CONFIG_NO_HZ_COMMON CPU load updatesFrederic Weisbecker
Some code in CPU load update only concern NO_HZ configs but it is built on all configurations. When NO_HZ isn't built, that code is harmless but just happens to take some useless ressources in CPU and memory: 1) one useless field in struct rq 2) jiffies record on every tick that is never used (cpu_load_update_periodic) 3) decay_load_missed is called two times on every tick to eventually return immediately with no action taken. And that function is dead code. For pure optimization purposes, lets conditionally build the NO_HZ related code. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Byungchul Park <byungchul.park@lge.com> Cc: Chris Metcalf <cmetcalf@ezchip.com> Cc: Christoph Lameter <cl@linux.com> Cc: Luiz Capitulino <lcapitulino@redhat.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul E . McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1461080211-16271-1-git-send-email-fweisbec@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-23sched/fair: Correctly handle nohz ticks CPU load accountingFrederic Weisbecker
Ticks can happen while the CPU is in dynticks-idle or dynticks-singletask mode. In fact "nohz" or "dynticks" only mean that we exit the periodic mode and we try to minimize the ticks as much as possible. The nohz subsystem uses a confusing terminology with the internal state "ts->tick_stopped" which is also available through its public interface with tick_nohz_tick_stopped(). This is a misnomer as the tick is instead reduced with the best effort rather than stopped. In the best case the tick can indeed be actually stopped but there is no guarantee about that. If a timer needs to fire one second later, a tick will fire while the CPU is in nohz mode and this is a very common scenario. Now this confusion happens to be a problem with CPU load updates: cpu_load_update_active() doesn't handle nohz ticks correctly because it assumes that ticks are completely stopped in nohz mode and that cpu_load_update_active() can't be called in dynticks mode. When that happens, the whole previous tickless load is ignored and the function just records the load for the current tick, ignoring potentially long idle periods behind. In order to solve this, we could account the current load for the previous nohz time but there is a risk that we account the load of a task that got freshly enqueued for the whole nohz period. So instead, lets record the dynticks load on nohz frame entry so we know what to record in case of nohz ticks, then use this record to account the tickless load on nohz ticks and nohz frame end. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Byungchul Park <byungchul.park@lge.com> Cc: Chris Metcalf <cmetcalf@ezchip.com> Cc: Christoph Lameter <cl@linux.com> Cc: Luiz Capitulino <lcapitulino@redhat.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul E . McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1460555812-25375-3-git-send-email-fweisbec@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-23sched/fair: Gather CPU load functions under a more conventional namespaceFrederic Weisbecker
The CPU load update related functions have a weak naming convention currently, starting with update_cpu_load_*() which isn't ideal as "update" is a very generic concept. Since two of these functions are public already (and a third is to come) that's enough to introduce a more conventional naming scheme. So let's do the following rename instead: update_cpu_load_*() -> cpu_load_update_*() Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Byungchul Park <byungchul.park@lge.com> Cc: Chris Metcalf <cmetcalf@ezchip.com> Cc: Christoph Lameter <cl@linux.com> Cc: Luiz Capitulino <lcapitulino@redhat.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul E . McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1460555812-25375-2-git-send-email-fweisbec@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-23sched/fair: Call cpufreq hook in additional pathsSteve Muckle
The cpufreq hook should be called any time the root CFS rq utilization changes. This can occur when a task is switched to or from the fair class, or a task moves between groups or CPUs, but these paths currently do not call the cpufreq hook. Fix this by adding the hook to attach_entity_load_avg() and detach_entity_load_avg(). Suggested-by: Vincent Guittot <vincent.guittot@linaro.org> Signed-off-by: Steve Muckle <smuckle@linaro.org> [ Added the .update_freq argument to update_cfs_rq_load_avg() to avoid a double cpufreq call. ] Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Byungchul Park <byungchul.park@lge.com> Cc: Dietmar Eggemann <dietmar.eggemann@arm.com> Cc: Juri Lelli <Juri.Lelli@arm.com> Cc: Michael Turquette <mturquette@baylibre.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Morten Rasmussen <morten.rasmussen@arm.com> Cc: Patrick Bellasi <patrick.bellasi@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rafael J. Wysocki <rafael@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1458858367-2831-1-git-send-email-smuckle@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-23sched/fair: Do not call cpufreq hook unless util changedSteve Muckle
There's no reason to call the cpufreq hook if the root cfs_rq utilization has not been modified. Signed-off-by: Steve Muckle <smuckle@linaro.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Dietmar Eggemann <dietmar.eggemann@arm.com> Cc: Juri Lelli <Juri.Lelli@arm.com> Cc: Michael Turquette <mturquette@baylibre.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Morten Rasmussen <morten.rasmussen@arm.com> Cc: Patrick Bellasi <patrick.bellasi@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rafael J. Wysocki <rafael@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vincent Guittot <vincent.guittot@linaro.org> Link: http://lkml.kernel.org/r/1458606068-7476-2-git-send-email-smuckle@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-23sched/fair: Move cpufreq hook to update_cfs_rq_load_avg()Steve Muckle
The cpufreq hook should be called whenever the root cfs_rq utilization changes so update_cfs_rq_load_avg() is a better place for it. The current location is not invoked in the enqueue_entity() or update_blocked_averages() paths. Suggested-by: Vincent Guittot <vincent.guittot@linaro.org> Signed-off-by: Steve Muckle <smuckle@linaro.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Dietmar Eggemann <dietmar.eggemann@arm.com> Cc: Juri Lelli <Juri.Lelli@arm.com> Cc: Michael Turquette <mturquette@baylibre.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Morten Rasmussen <morten.rasmussen@arm.com> Cc: Patrick Bellasi <patrick.bellasi@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rafael J. Wysocki <rafael@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1458606068-7476-1-git-send-email-smuckle@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-23sched/fair: Fix asym packing to select correct CPUSrikar Dronamraju
When asymmetric packing is set in the sched_domain and target CPU is busy, update_sd_pick_busiest() may not select the busiest runqueue. When target CPU is busy, find_busiest_group() will ignore checks for asym packing and may continue to load balance using the currently selected not-the-busiest runqueue as source runqueue. Selecting the busiest runqueue as source when the target CPU is busy, should result in achieving much better load balance. Also when target CPU is not busy and asymmetric packing is set in sd, select higher CPU as source CPU for load balancing. While doing this change, move the check to see if target CPU is busy into check_asym_packing(). The extent of performance benefit from this change decreases with the increasing load. However there is benefit in undercommit as well as overcommit conditions. 1. Record per second ebizzy (32 threads) on a 64 CPU power 7 box. (5 iterations) 4.6.0-rc2 Testcase: Min Max Avg StdDev ebizzy: 5223767.00 10368236.00 7946971.00 1753094.76 4.6.0-rc2+asym-changes Testcase: Min Max Avg StdDev %Change ebizzy: 8617191.00 13872356.00 11383980.00 1783400.89 +24.78% 2. Record per second ebizzy (64 threads) on a 64 CPU power 7 box. (5 iterations) 4.6.0-rc2 Testcase: Min Max Avg StdDev ebizzy: 6497666.00 18399783.00 10818093.20 4051452.08 4.6.0-rc2+asym-changes Testcase: Min Max Avg StdDev %Change ebizzy: 7567365.00 19456937.00 11674063.60 4295407.48 +4.40% 3. Record per second ebizzy (128 threads) on a 64 CPU power 7 box. (5 iterations) 4.6.0-rc2 Testcase: Min Max Avg StdDev ebizzy: 37073983.00 40341911.00 38776241.80 1259766.82 4.6.0-rc2+asym-changes Testcase: Min Max Avg StdDev %Change ebizzy: 38030399.00 41333378.00 39827404.40 1255001.86 +2.54% Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Gautham R Shenoy <ego@linux.vnet.ibm.com> Cc: Michael Neuling <mikey@neuling.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com> Link: http://lkml.kernel.org/r/1459948660-16073-1-git-send-email-srikar@linux.vnet.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-23Merge tag 'v4.6-rc4' into sched/core, to refresh the treeIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-22cpu/hotplug: Fix rollback during error-out in __cpu_disable()Sebastian Andrzej Siewior
The recent introduction of the hotplug thread which invokes the callbacks on the plugged cpu, cased the following regression: If takedown_cpu() fails, then we run into several issues: 1) The rollback of the target cpu states is not invoked. That leaves the smp threads and the hotplug thread in disabled state. 2) notify_online() is executed due to a missing skip_onerr flag. That causes that both CPU_DOWN_FAILED and CPU_ONLINE notifications are invoked which confuses quite some notifiers. 3) The CPU_DOWN_FAILED notification is not invoked on the target CPU. That's not an issue per se, but it is inconsistent and in consequence blocks the patches which rely on these states being invoked on the target CPU and not on the controlling cpu. It also does not preserve the strict call order on rollback which is problematic for the ongoing state machine conversion as well. To fix this we add a rollback flag to the remote callback machinery and invoke the rollback including the CPU_DOWN_FAILED notification on the remote cpu. Further mark the notify online state with 'skip_onerr' so we don't get a double invokation. This workaround will go away once we moved the unplug invocation to the target cpu itself. [ tglx: Massaged changelog and moved the CPU_DOWN_FAILED notifiaction to the target cpu ] Fixes: 4cb28ced23c4 ("cpu/hotplug: Create hotplug threads") Reported-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: linux-s390@vger.kernel.org Cc: rt@linutronix.de Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Anna-Maria Gleixner <anna-maria@linutronix.de> Link: http://lkml.kernel.org/r/20160408124015.GA21960@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-04-21Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netLinus Torvalds
Pull networking fixes from David Miller: 1) Fix memory leak in iwlwifi, from Matti Gottlieb. 2) Add missing registration of netfilter arp_tables into initial namespace, from Florian Westphal. 3) Fix potential NULL deref in DecNET routing code. 4) Restrict NETLINK_URELEASE to truly bound sockets only, from Dmitry Ivanov. 5) Fix dst ref counting in VRF, from David Ahern. 6) Fix TSO segmenting limits in i40e driver, from Alexander Duyck. 7) Fix heap leak in PACKET_DIAG_MCLIST, from Mathias Krause. 8) Ravalidate IPV6 datagram socket cached routes properly, particularly with UDP, from Martin KaFai Lau. 9) Fix endian bug in RDS dp_ack_seq handling, from Qing Huang. 10) Fix stats typing in bcmgenet driver, from Eric Dumazet. 11) Openvswitch needs to orphan SKBs before ipv6 fragmentation handing, from Joe Stringer. 12) SPI device reference leak in spi_ks8895 PHY driver, from Mark Brown. 13) atl2 doesn't actually support scatter-gather, so don't advertise the feature. From Ben Hucthings. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (72 commits) openvswitch: use flow protocol when recalculating ipv6 checksums Driver: Vmxnet3: set CHECKSUM_UNNECESSARY for IPv6 packets atl2: Disable unimplemented scatter/gather feature net/mlx4_en: Split SW RX dropped counter per RX ring net/mlx4_core: Don't allow to VF change global pause settings net/mlx4_core: Avoid repeated calls to pci enable/disable net/mlx4_core: Implement pci_resume callback net: phy: spi_ks8895: Don't leak references to SPI devices net: ethernet: davinci_emac: Fix platform_data overwrite net: ethernet: davinci_emac: Fix Unbalanced pm_runtime_enable qede: Fix single MTU sized packet from firmware GRO flow qede: Fix setting Skb network header qede: Fix various memory allocation error flows for fastpath tcp: Merge tx_flags and tskey in tcp_shifted_skb tcp: Merge tx_flags and tskey in tcp_collapse_retrans drivers: net: cpsw: fix wrong regs access in cpsw_ndo_open tcp: Fix SOF_TIMESTAMPING_TX_ACK when handling dup acks openvswitch: Orphan skbs before IPv6 defrag Revert "Prevent NUll pointer dereference with two PHYs on cpsw" VSOCK: Only check error on skb_recv_datagram when skb is NULL ...
2016-04-21genirq: Dont allow affinity mask to be updated on IPIsMatt Redfearn
The IPI domain re-purposes the IRQ affinity to signify the mask of CPUs that this IPI will deliver to. This must not be modified before the IPI is destroyed again, so set the IRQ_NO_BALANCING flag to prevent the affinity being overwritten by setup_affinity(). Without this, if an IPI is reserved for a single target CPU, then allocated using __setup_irq(), the affinity is overwritten with cpu_online_mask. When ipi_destroy() is subsequently called on a multi-cpu system, it will attempt to free cpumask_weight() IRQs that were never allocated, and crash. Fixes: d17bf24e6952 ("genirq: Add a new generic IPI reservation code to irq core") Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com> Cc: linux-mips@linux-mips.org Cc: jason@lakedaemon.net Cc: marc.zyngier@arm.com Cc: ralf@linux-mips.org Cc: Qais Yousef <qsyousef@gmail.com> Cc: lisa.parratt@imgtec.com Link: http://lkml.kernel.org/r/1461229712-13057-1-git-send-email-matt.redfearn@imgtec.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-04-21futex: Acknowledge a new waiter in counter before plistDavidlohr Bueso
Otherwise an incoming waker on the dest hash bucket can miss the waiter adding itself to the plist during the lockless check optimization (small window but still the correct way of doing this); similarly to the decrement counterpart. Suggested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Davidlohr Bueso <dbueso@suse.de> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: bigeasy@linutronix.de Cc: dvhart@infradead.org Cc: stable@kernel.org Link: http://lkml.kernel.org/r/1461208164-29150-1-git-send-email-dave@stgolabs.net Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-04-20futex: Handle unlock_pi race gracefullySebastian Andrzej Siewior
If userspace calls UNLOCK_PI unconditionally without trying the TID -> 0 transition in user space first then the user space value might not have the waiters bit set. This opens the following race: CPU0 CPU1 uval = get_user(futex) lock(hb) lock(hb) futex |= FUTEX_WAITERS .... unlock(hb) cmpxchg(futex, uval, newval) So the cmpxchg fails and returns -EINVAL to user space, which is wrong because the futex value is valid. To handle this (yes, yet another) corner case gracefully, check for a flag change and retry. [ tglx: Massaged changelog and slightly reworked implementation ] Fixes: ccf9e6a80d9e ("futex: Make unlock_pi more robust") Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: stable@vger.kernel.org Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Darren Hart <dvhart@linux.intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1460723739-5195-1-git-send-email-bigeasy@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-04-19locking/pvqspinlock: Fix division by zero in qstat_read()Davidlohr Bueso
While playing with the qstat statistics (in <debugfs>/qlockstat/) I ran into the following splat on a VM when opening pv_hash_hops: divide error: 0000 [#1] SMP ... RIP: 0010:[<ffffffff810b61fe>] [<ffffffff810b61fe>] qstat_read+0x12e/0x1e0 ... Call Trace: [<ffffffff811cad7c>] ? mem_cgroup_commit_charge+0x6c/0xd0 [<ffffffff8119750c>] ? page_add_new_anon_rmap+0x8c/0xd0 [<ffffffff8118d3b9>] ? handle_mm_fault+0x1439/0x1b40 [<ffffffff811937a9>] ? do_mmap+0x449/0x550 [<ffffffff811d3de3>] ? __vfs_read+0x23/0xd0 [<ffffffff811d4ab2>] ? rw_verify_area+0x52/0xd0 [<ffffffff811d4bb1>] ? vfs_read+0x81/0x120 [<ffffffff811d5f12>] ? SyS_read+0x42/0xa0 [<ffffffff815720f6>] ? entry_SYSCALL_64_fastpath+0x1e/0xa8 Fix this by verifying that qstat_pv_kick_unlock is in fact non-zero, similarly to what the qstat_pv_latency_wake case does, as if nothing else, this can come from resetting the statistics, thus having 0 kicks should be quite valid in this context. Signed-off-by: Davidlohr Bueso <dbueso@suse.de> Reviewed-by: Waiman Long <Waiman.Long@hpe.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: dave@stgolabs.net Cc: waiman.long@hpe.com Link: http://lkml.kernel.org/r/1460961103-24953-1-git-send-email-dave@stgolabs.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-16Merge branch 'locking-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull locking fixlet from Ingo Molnar: "Fixes a build warning on certain Kconfig combinations" * 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: locking/lockdep: Fix print_collision() unused warning
2016-04-14/proc/iomem: only expose physical resource addresses to privileged usersLinus Torvalds
In commit c4004b02f8e5b ("x86: remove the kernel code/data/bss resources from /proc/iomem") I was hoping to remove the phyiscal kernel address data from /proc/iomem entirely, but that had to be reverted because some system programs actually use it. This limits all the detailed resource information to properly credentialed users instead. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-14bpf/verifier: reject invalid LD_ABS | BPF_DW instructionAlexei Starovoitov
verifier must check for reserved size bits in instruction opcode and reject BPF_LD | BPF_ABS | BPF_DW and BPF_LD | BPF_IND | BPF_DW instructions, otherwise interpreter will WARN_RATELIMIT on them during execution. Fixes: ddd872bc3098 ("bpf: verifier: add checks for BPF_ABS | BPF_IND instructions") Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-13sched/cpuacct: Check for NULL when using task_pt_regs()Anton Blanchard
task_pt_regs() can return NULL for kernel threads, so add a check. This fixes an oops at boot on ppc64. Reported-and-Tested-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Tested-by: Zhao Lei <zhaolei@cn.fujitsu.com> Signed-off-by: Anton Blanchard <anton@samba.org> Acked-by: Zhao Lei <zhaolei@cn.fujitsu.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: efault@gmx.de Cc: htejun@gmail.com Cc: linuxppc-dev@lists.ozlabs.org Cc: tj@kernel.org Cc: yangds.fnst@cn.fujitsu.com Link: http://lkml.kernel.org/r/20160406215950.04bc3f0b@kryten Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-13sched/clock: Make local_clock()/cpu_clock() inlineDaniel Lezcano
The local_clock/cpu_clock functions were changed to prevent a double identical test with sched_clock_cpu() when HAVE_UNSTABLE_SCHED_CLOCK is set. That resulted in one line functions. As these functions are in all the cases one line functions and in the hot path, it is useful to specify them as static inline in order to give a strong hint to the compiler. After verification, it appears the compiler does not inline them without this hint. Change those functions to static inline. sched_clock_cpu() is called via the inlined local_clock()/cpu_clock() functions from sched.h. So any module code including sched.h will reference sched_clock_cpu(). Thus it must be exported with the EXPORT_SYMBOL_GPL macro. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1460385514-14700-2-git-send-email-daniel.lezcano@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-13sched/clock: Remove pointless test in cpu_clock/local_clockDaniel Lezcano
In case the HAVE_UNSTABLE_SCHED_CLOCK config is set, the cpu_clock() version checks if sched_clock_stable() is not set and calls sched_clock_cpu(), otherwise it calls sched_clock(). sched_clock_cpu() checks also if sched_clock_stable() is set and, if true, calls sched_clock(). sched_clock() will be called in sched_clock_cpu() if sched_clock_stable() is true. Remove the duplicate test by directly calling sched_clock_cpu() and let the static key act in this function instead. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1460385514-14700-1-git-send-email-daniel.lezcano@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-13sched/debug: Don't dump sched debug info in SysRq-WRabin Vincent
sysrq_sched_debug_show() can dump a lot of information. Don't print out all that if we're just trying to get a list of blocked tasks (SysRq-W). The information is still accessible with SysRq-T. Signed-off-by: Rabin Vincent <rabinv@axis.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1459777322-30902-1-git-send-email-rabin.vincent@axis.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-04Merge branch 'PAGE_CACHE_SIZE-removal'Linus Torvalds
Merge PAGE_CACHE_SIZE removal patches from Kirill Shutemov: "PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time ago with promise that one day it will be possible to implement page cache with bigger chunks than PAGE_SIZE. This promise never materialized. And unlikely will. Let's stop pretending that pages in page cache are special. They are not. The first patch with most changes has been done with coccinelle. The second is manual fixups on top. The third patch removes macros definition" [ I was planning to apply this just before rc2, but then I spaced out, so here it is right _after_ rc2 instead. As Kirill suggested as a possibility, I could have decided to only merge the first two patches, and leave the old interfaces for compatibility, but I'd rather get it all done and any out-of-tree modules and patches can trivially do the converstion while still also working with older kernels, so there is little reason to try to maintain the redundant legacy model. - Linus ] * PAGE_CACHE_SIZE-removal: mm: drop PAGE_CACHE_* and page_cache_{get,release} definition mm, fs: remove remaining PAGE_CACHE_* and page_cache_{get,release} usage mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros
2016-04-04mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macrosKirill A. Shutemov
PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time ago with promise that one day it will be possible to implement page cache with bigger chunks than PAGE_SIZE. This promise never materialized. And unlikely will. We have many places where PAGE_CACHE_SIZE assumed to be equal to PAGE_SIZE. And it's constant source of confusion on whether PAGE_CACHE_* or PAGE_* constant should be used in a particular case, especially on the border between fs and mm. Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much breakage to be doable. Let's stop pretending that pages in page cache are special. They are not. The changes are pretty straight-forward: - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN}; - page_cache_get() -> get_page(); - page_cache_release() -> put_page(); This patch contains automated changes generated with coccinelle using script below. For some reason, coccinelle doesn't patch header files. I've called spatch for them manually. The only adjustment after coccinelle is revert of changes to PAGE_CAHCE_ALIGN definition: we are going to drop it later. There are few places in the code where coccinelle didn't reach. I'll fix them manually in a separate patch. Comments and documentation also will be addressed with the separate patch. virtual patch @@ expression E; @@ - E << (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ expression E; @@ - E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ @@ - PAGE_CACHE_SHIFT + PAGE_SHIFT @@ @@ - PAGE_CACHE_SIZE + PAGE_SIZE @@ @@ - PAGE_CACHE_MASK + PAGE_MASK @@ expression E; @@ - PAGE_CACHE_ALIGN(E) + PAGE_ALIGN(E) @@ expression E; @@ - page_cache_get(E) + get_page(E) @@ expression E; @@ - page_cache_release(E) + put_page(E) Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-04locking/lockdep: Fix print_collision() unused warningBorislav Petkov
Fix this: kernel/locking/lockdep.c:2051:13: warning: ‘print_collision’ defined but not used [-Wunused-function] static void print_collision(struct task_struct *curr, ^ Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1459759327-2880-1-git-send-email-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-03Merge branch 'perf-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf fixes from Ingo Molnar: "Misc kernel side fixes: - fix event leak - fix AMD PMU driver bug - fix core event handling bug - fix build bug on certain randconfigs Plus misc tooling fixes" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf/x86/amd/ibs: Fix pmu::stop() nesting perf/core: Don't leak event in the syscall error path perf/core: Fix time tracking bug with multiplexing perf jit: genelf makes assumptions about endian perf hists: Fix determination of a callchain node's childlessness perf tools: Add missing initialization of perf_sample.cpumode in synthesized samples perf tools: Fix build break on powerpc perf/x86: Move events_sysfs_show() outside CPU_SUP_INTEL perf bench: Fix detached tarball building due to missing 'perf bench memcpy' headers perf tests: Fix tarpkg build test error output redirection
2016-04-03Merge branch 'core-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull core kernel fixes from Ingo Molnar: "This contains the nohz/atomic cleanup/fix for the fetch_or() ugliness you noted during the original nohz pull request, plus there's also misc fixes: - fix liblockdep build bug - fix uapi header build bug - print more lockdep hash collision info to help debug recent reports of hash collisions - update MAINTAINERS email address" * 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: MAINTAINERS: Update my email address locking/lockdep: Print chain_key collision information uapi/linux/stddef.h: Provide __always_inline to userspace headers tools/lib/lockdep: Fix unsupported 'basename -s' in run_tests.sh locking/atomic, sched: Unexport fetch_or() timers/nohz: Convert tick dependency mask to atomic_t locking/atomic: Introduce atomic_fetch_or()
2016-04-01Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netLinus Torvalds
Pull networking fixes from David Miller: 1) Missing device reference in IPSEC input path results in crashes during device unregistration. From Subash Abhinov Kasiviswanathan. 2) Per-queue ISR register writes not being done properly in macb driver, from Cyrille Pitchen. 3) Stats accounting bugs in bcmgenet, from Patri Gynther. 4) Lightweight tunnel's TTL and TOS were swapped in netlink dumps, from Quentin Armitage. 5) SXGBE driver has off-by-one in probe error paths, from Rasmus Villemoes. 6) Fix race in save/swap/delete options in netfilter ipset, from Vishwanath Pai. 7) Ageing time of bridge not set properly when not operating over a switchdev device. Fix from Haishuang Yan. 8) Fix GRO regression wrt nested FOU/GUE based tunnels, from Alexander Duyck. 9) IPV6 UDP code bumps wrong stats, from Eric Dumazet. 10) FEC driver should only access registers that actually exist on the given chipset, fix from Fabio Estevam. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (73 commits) net: mvneta: fix changing MTU when using per-cpu processing stmmac: fix MDIO settings Revert "stmmac: Fix 'eth0: No PHY found' regression" stmmac: fix TX normal DESC net: mvneta: use cache_line_size() to get cacheline size net: mvpp2: use cache_line_size() to get cacheline size net: mvpp2: fix maybe-uninitialized warning tun, bpf: fix suspicious RCU usage in tun_{attach, detach}_filter net: usb: cdc_ncm: adding Telit LE910 V2 mobile broadband card rtnl: fix msg size calculation in if_nlmsg_size() fec: Do not access unexisting register in Coldfire net: mvneta: replace MVNETA_CPU_D_CACHE_LINE_SIZE with L1_CACHE_BYTES net: mvpp2: replace MVPP2_CPU_D_CACHE_LINE_SIZE with L1_CACHE_BYTES net: dsa: mv88e6xxx: Clear the PDOWN bit on setup net: dsa: mv88e6xxx: Introduce _mv88e6xxx_phy_page_{read, write} bpf: make padding in bpf_tunnel_key explicit ipv6: udp: fix UDP_MIB_IGNOREDMULTI updates bnxt_en: Fix ethtool -a reporting. bnxt_en: Fix typo in bnxt_hwrm_set_pause_common(). bnxt_en: Implement proper firmware message padding. ...
2016-03-31locking/lockdep: Print chain_key collision informationAlfredo Alvarez Fernandez
A sequence of pairs [class_idx -> corresponding chain_key iteration] is printed for both the current held_lock chain and the cached chain. That exposes the two different class_idx sequences that led to that particular hash value. This helps with debugging hash chain collision reports. Signed-off-by: Alfredo Alvarez Fernandez <alfredoalvarezfernandez@gmail.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-fsdevel@vger.kernel.org Cc: sedat.dilek@gmail.com Cc: tytso@mit.edu Link: http://lkml.kernel.org/r/1459357416-19190-1-git-send-email-alfredoalvarezernandez@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-31sched/fair: Initiate a new task's util avg to a bounded valueYuyang Du
A new task's util_avg is set to full utilization of a CPU (100% time running). This accelerates a new task's utilization ramp-up, useful to boost its execution in early time. However, it may result in (insanely) high utilization for a transient time period when a flood of tasks are spawned. Importantly, it violates the "fundamentally bounded" CPU utilization, and its side effect is negative if we don't take any measure to bound it. This patch proposes an algorithm to address this issue. It has two methods to approach a sensible initial util_avg: (1) An expected (or average) util_avg based on its cfs_rq's util_avg: util_avg = cfs_rq->util_avg / (cfs_rq->load_avg + 1) * se.load.weight (2) A trajectory of how successive new tasks' util develops, which gives 1/2 of the left utilization budget to a new task such that the additional util is noticeably large (when overall util is low) or unnoticeably small (when overall util is high enough). In the meantime, the aggregate utilization is well bounded: util_avg_cap = (1024 - cfs_rq->avg.util_avg) / 2^n where n denotes the nth task. If util_avg is larger than util_avg_cap, then the effective util is clamped to the util_avg_cap. Reported-by: Andrey Ryabinin <aryabinin@virtuozzo.com> Signed-off-by: Yuyang Du <yuyang.du@intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: bsegall@google.com Cc: morten.rasmussen@arm.com Cc: pjt@google.com Cc: steve.muckle@linaro.org Link: http://lkml.kernel.org/r/1459283456-21682-1-git-send-email-yuyang.du@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-31sched/fair: Update comments after a variable renameYuyang Du
The following commit: ed82b8a1ff76 ("sched/core: Move the sched_to_prio[] arrays out of line") renamed prio_to_weight to sched_prio_to_weight, but the old name was not updated in comments. Signed-off-by: Yuyang Du <yuyang.du@intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1459292871-22531-1-git-send-email-yuyang.du@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-31sched/core: Add preempt checks in preempt_schedule() codeSteven Rostedt
While testing the tracer preemptoff, I hit this strange trace: <...>-259 0...1 0us : schedule <-worker_thread <...>-259 0d..1 0us : rcu_note_context_switch <-__schedule <...>-259 0d..1 0us : rcu_sched_qs <-rcu_note_context_switch <...>-259 0d..1 0us : rcu_preempt_qs <-rcu_note_context_switch <...>-259 0d..1 0us : _raw_spin_lock <-__schedule <...>-259 0d..1 0us : preempt_count_add <-_raw_spin_lock <...>-259 0d..2 0us : do_raw_spin_lock <-_raw_spin_lock <...>-259 0d..2 1us : deactivate_task <-__schedule <...>-259 0d..2 1us : update_rq_clock.part.84 <-deactivate_task <...>-259 0d..2 1us : dequeue_task_fair <-deactivate_task <...>-259 0d..2 1us : dequeue_entity <-dequeue_task_fair <...>-259 0d..2 1us : update_curr <-dequeue_entity <...>-259 0d..2 1us : update_min_vruntime <-update_curr <...>-259 0d..2 1us : cpuacct_charge <-update_curr <...>-259 0d..2 1us : __rcu_read_lock <-cpuacct_charge <...>-259 0d..2 1us : __rcu_read_unlock <-cpuacct_charge <...>-259 0d..2 1us : clear_buddies <-dequeue_entity <...>-259 0d..2 1us : account_entity_dequeue <-dequeue_entity <...>-259 0d..2 2us : update_min_vruntime <-dequeue_entity <...>-259 0d..2 2us : update_cfs_shares <-dequeue_entity <...>-259 0d..2 2us : hrtick_update <-dequeue_task_fair <...>-259 0d..2 2us : wq_worker_sleeping <-__schedule <...>-259 0d..2 2us : kthread_data <-wq_worker_sleeping <...>-259 0d..2 2us : pick_next_task_fair <-__schedule <...>-259 0d..2 2us : check_cfs_rq_runtime <-pick_next_task_fair <...>-259 0d..2 2us : pick_next_entity <-pick_next_task_fair <...>-259 0d..2 2us : clear_buddies <-pick_next_entity <...>-259 0d..2 2us : pick_next_entity <-pick_next_task_fair <...>-259 0d..2 2us : clear_buddies <-pick_next_entity <...>-259 0d..2 2us : set_next_entity <-pick_next_task_fair <...>-259 0d..2 3us : put_prev_entity <-pick_next_task_fair <...>-259 0d..2 3us : check_cfs_rq_runtime <-put_prev_entity <...>-259 0d..2 3us : set_next_entity <-pick_next_task_fair gnome-sh-1031 0d..2 3us : finish_task_switch <-__schedule gnome-sh-1031 0d..2 3us : _raw_spin_unlock_irq <-finish_task_switch gnome-sh-1031 0d..2 3us : do_raw_spin_unlock <-_raw_spin_unlock_irq gnome-sh-1031 0...2 3us!: preempt_count_sub <-_raw_spin_unlock_irq gnome-sh-1031 0...1 582us : do_raw_spin_lock <-_raw_spin_lock gnome-sh-1031 0...1 583us : _raw_spin_unlock <-drm_gem_object_lookup gnome-sh-1031 0...1 583us : do_raw_spin_unlock <-_raw_spin_unlock gnome-sh-1031 0...1 583us : preempt_count_sub <-_raw_spin_unlock gnome-sh-1031 0...1 584us : _raw_spin_unlock <-drm_gem_object_lookup gnome-sh-1031 0...1 584us+: trace_preempt_on <-drm_gem_object_lookup gnome-sh-1031 0...1 603us : <stack trace> => preempt_count_sub => _raw_spin_unlock => drm_gem_object_lookup => i915_gem_madvise_ioctl => drm_ioctl => do_vfs_ioctl => SyS_ioctl => entry_SYSCALL_64_fastpath As I'm tracing preemption disabled, it seemed incorrect that the trace would go across a schedule and report not being in the scheduler. Looking into this I discovered the problem. schedule() calls preempt_disable() but the preempt_schedule() calls preempt_enable_notrace(). What happened above was that the gnome-shell task was preempted on another CPU, migrated over to the idle cpu. The tracer stared with idle calling schedule(), which called preempt_disable(), but then gnome-shell finished, and it enabled preemption with preempt_enable_notrace() that does stop the trace, even though preemption was enabled. The purpose of the preempt_disable_notrace() in the preempt_schedule() is to prevent function tracing from going into an infinite loop. Because function tracing can trace the preempt_enable/disable() calls that are traced. The problem with function tracing is: NEED_RESCHED set preempt_schedule() preempt_disable() preempt_count_inc() function trace (before incrementing preempt count) preempt_disable_notrace() preempt_enable_notrace() sees NEED_RESCHED set preempt_schedule() (repeat) Now by breaking out the preempt off/on tracing into their own code: preempt_disable_check() and preempt_enable_check(), we can add these to the preempt_schedule() code. As preemption would then be disabled, even if they were to be traced by the function tracer, the disabled preemption would prevent the recursion. Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20160321112339.6dc78ad6@gandalf.local.home Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-31sched/numa: Remove unnecessary NUMA dequeue update from non-SMP kernelsTim Chen
In account_entity_enqueue(), we do not do account_numa_enqueue() as NUMA balancing is not needed for UP kernels. Hence, we should remove the account_numa_dequeue() call from account_entity_dequeue() for UP kernels. Signed-off-by: Tim Chen <tim.c.chen@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1454366879.21738.29.camel@schen9-desk2.jf.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-31sched/fair: Reset nr_balance_failed after active balancingSrikar Dronamraju
To force a task migration during active balancing, nr_balance_failed is set to cache_nice_tries + 1. However nr_balance_failed is not reset. As a side effect, the next regular load balance under the same sd, a cache hot task might be migrated, just because nr_balance_failed count is high. Resetting nr_balance_failed after a successful active balance ensures that a hot task is not unreasonably migrated. This can be verified by looking at othe number of hot task migrations reported by /proc/schedstat. Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1458735884-30105-1-git-send-email-srikar@linux.vnet.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-31sched/cpuacct: Split usage accounting into user_usage and sys_usageDongsheng Yang
Sometimes, cpuacct.usage is not detailed enough to see how much CPU usage a group had. We want to know how much time it used in user mode and how much in kernel mode. This patch introduces more files to give this information: # ls /sys/fs/cgroup/cpuacct/cpuacct.usage* /sys/fs/cgroup/cpuacct/cpuacct.usage /sys/fs/cgroup/cpuacct/cpuacct.usage_percpu /sys/fs/cgroup/cpuacct/cpuacct.usage_user /sys/fs/cgroup/cpuacct/cpuacct.usage_percpu_user /sys/fs/cgroup/cpuacct/cpuacct.usage_sys /sys/fs/cgroup/cpuacct/cpuacct.usage_percpu_sys ... while keeping the ABI with the existing counter. Signed-off-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com> [ Ported to newer kernels. ] Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Tejun Heo <tj@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Tejun Heo <htejun@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/aa171da036b520b51c79549e9b3215d29473f19d.1458635566.git.zhaolei@cn.fujitsu.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-31sched/cpuacct: Show all possible CPUs in cpuacct outputZhao Lei
Current code show stats of online CPUs in cpuacct.statcpus, show stats of present cpus in cpuacct.usage(_percpu), and using present CPUs for setting cpuacct.usage. It will cause inconsistent result when a CPU is online or offline or hotpluged. We should always use possible CPUs to avoid above problem. Here are the contents of a cpuacct.usage_percpu sysfs file, on a 4 CPU system with maxcpus=32: Before the patch: # cat cpuacct.usage_percpu 2456565 411435 1052897 832584 After the patch: # cat cpuacct.usage_percpu 2456565 411435 1052897 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Suggested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Tejun Heo <htejun@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/a11d56cef12d0b4807f8be3a46bf9798c3014d59.1458635566.git.zhaolei@cn.fujitsu.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-31perf/core: Don't leak event in the syscall error pathAlexander Shishkin
In the error path, event_file not being NULL is used to determine whether the event itself still needs to be free'd, so fix it up to avoid leaking. Reported-by: Leon Yu <chianglungyu@gmail.com> Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Fixes: 130056275ade ("perf: Do not double free") Link: http://lkml.kernel.org/r/87twk06yxp.fsf@ashishki-desk.ger.corp.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-31perf/core: Fix time tracking bug with multiplexingPeter Zijlstra
Stephane reported that commit: 3cbaa5906967 ("perf: Fix ctx time tracking by introducing EVENT_TIME") introduced a regression wrt. time tracking, as easily observed by: > This patch introduce a bug in the time tracking of events when > multiplexing is used. > > The issue is easily reproducible with the following perf run: > > $ perf stat -a -C 0 -e branches,branches,branches,branches,branches,branches -I 1000 > 1.000730239 652,394 branches (66.41%) > 1.000730239 597,809 branches (66.41%) > 1.000730239 593,870 branches (66.63%) > 1.000730239 651,440 branches (67.03%) > 1.000730239 656,725 branches (66.96%) > 1.000730239 <not counted> branches > > One branches event is shown as not having run. Yet, with > multiplexing, all events should run especially with a 1s (-I 1000) > interval. The delta for time_running comes out to 0. Yet, the event > has run because the kernel is actually multiplexing the events. The > problem is that the time tracking is the kernel and especially in > ctx_sched_out() is wrong now. > > The problem is that in case that the kernel enters ctx_sched_out() with the > following state: > ctx->is_active=0x7 event_type=0x1 > Call Trace: > [<ffffffff813ddd41>] dump_stack+0x63/0x82 > [<ffffffff81182bdc>] ctx_sched_out+0x2bc/0x2d0 > [<ffffffff81183896>] perf_mux_hrtimer_handler+0xf6/0x2c0 > [<ffffffff811837a0>] ? __perf_install_in_context+0x130/0x130 > [<ffffffff810f5818>] __hrtimer_run_queues+0xf8/0x2f0 > [<ffffffff810f6097>] hrtimer_interrupt+0xb7/0x1d0 > [<ffffffff810509a8>] local_apic_timer_interrupt+0x38/0x60 > [<ffffffff8175ca9d>] smp_apic_timer_interrupt+0x3d/0x50 > [<ffffffff8175ac7c>] apic_timer_interrupt+0x8c/0xa0 > > In that case, the test: > if (is_active & EVENT_TIME) > > will be false and the time will not be updated. Time must always be updated on > sched out. Fix this by always updating time if EVENT_TIME was set, as opposed to only updating time when EVENT_TIME changed. Reported-by: Stephane Eranian <eranian@google.com> Tested-by: Stephane Eranian <eranian@google.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: kan.liang@intel.com Cc: namhyung@kernel.org Fixes: 3cbaa5906967 ("perf: Fix ctx time tracking by introducing EVENT_TIME") Link: http://lkml.kernel.org/r/20160329072644.GB3408@twins.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-29locking/atomic, sched: Unexport fetch_or()Frederic Weisbecker
This patch functionally reverts: 5fd7a09cfb8c ("atomic: Export fetch_or()") During the merge Linus observed that the generic version of fetch_or() was messy: " This makes the ugly "fetch_or()" macro that the scheduler used internally a new generic helper, and does a bad job at it. " e23604edac2a Merge branch 'timers-nohz-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Now that we have introduced atomic_fetch_or(), fetch_or() is only used by the scheduler in order to deal with thread_info flags which type can vary across architectures. Lets confine fetch_or() back to the scheduler so that we encourage future users to use the more robust and well typed atomic_t version instead. While at it, fetch_or() gets robustified, pasting improvements from a previous patch by Ingo Molnar that avoids needless expression re-evaluations in the loop. Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1458830281-4255-4-git-send-email-fweisbec@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-29timers/nohz: Convert tick dependency mask to atomic_tFrederic Weisbecker
The tick dependency mask was intially unsigned long because this is the type on which clear_bit() operates on and fetch_or() accepts it. But now that we have atomic_fetch_or(), we can instead use atomic_andnot() to clear the bit. This consolidates the type of our tick dependency mask, reduce its size on structures and benefit from possible architecture optimizations on atomic_t operations. Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1458830281-4255-3-git-send-email-fweisbec@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-25arch, ftrace: for KASAN put hard/soft IRQ entries into separate sectionsAlexander Potapenko
KASAN needs to know whether the allocation happens in an IRQ handler. This lets us strip everything below the IRQ entry point to reduce the number of unique stack traces needed to be stored. Move the definition of __irq_entry to <linux/interrupt.h> so that the users don't need to pull in <linux/ftrace.h>. Also introduce the __softirq_entry macro which is similar to __irq_entry, but puts the corresponding functions to the .softirqentry.text section. Signed-off-by: Alexander Potapenko <glider@google.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Andrey Konovalov <adech.fo@gmail.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: Konstantin Serebryany <kcc@google.com> Cc: Dmitry Chernenkov <dmitryc@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-25oom: clear TIF_MEMDIE after oom_reaper managed to unmap the address spaceMichal Hocko
When oom_reaper manages to unmap all the eligible vmas there shouldn't be much of the freable memory held by the oom victim left anymore so it makes sense to clear the TIF_MEMDIE flag for the victim and allow the OOM killer to select another task. The lack of TIF_MEMDIE also means that the victim cannot access memory reserves anymore but that shouldn't be a problem because it would get the access again if it needs to allocate and hits the OOM killer again due to the fatal_signal_pending resp. PF_EXITING check. We can safely hide the task from the OOM killer because it is clearly not a good candidate anymore as everyhing reclaimable has been torn down already. This patch will allow to cap the time an OOM victim can keep TIF_MEMDIE and thus hold off further global OOM killer actions granted the oom reaper is able to take mmap_sem for the associated mm struct. This is not guaranteed now but further steps should make sure that mmap_sem for write should be blocked killable which will help to reduce such a lock contention. This is not done by this patch. Note that exit_oom_victim might be called on a remote task from __oom_reap_task now so we have to check and clear the flag atomically otherwise we might race and underflow oom_victims or wake up waiters too early. Signed-off-by: Michal Hocko <mhocko@suse.com> Suggested-by: Johannes Weiner <hannes@cmpxchg.org> Suggested-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Andrea Argangeli <andrea@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Hugh Dickins <hughd@google.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>