summaryrefslogtreecommitdiff
path: root/kernel
AgeCommit message (Collapse)Author
2012-03-12Merge branch 'perf/urgent' into perf/coreIngo Molnar
Merge reason: We are going to queue up a dependent patch. Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-03-12sched: Fix nohz load accounting -- again!Peter Zijlstra
Various people reported nohz load tracking still being wrecked, but Doug spotted the actual problem. We fold the nohz remainder in too soon, causing us to loose samples and under-account. So instead of playing catch-up up-front, always do a single load-fold with whatever state we encounter and only then fold the nohz remainder and play catch-up. Reported-by: Doug Smythies <dsmythies@telus.net> Reported-by: LesÅ=82aw Kope=C4=87 <leslaw.kopec@nasza-klasa.pl> Reported-by: Aman Gupta <aman@tmm1.net> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/n/tip-4v31etnhgg9kwd6ocgx3rxl8@git.kernel.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-03-12sched: Update yield() docsPeter Zijlstra
Suggested-by: Joe Perches <joe@perches.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1331056466.11248.327.camel@twins Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-03-12printk/sched: Introduce special printk_sched() for those awkward momentsPeter Zijlstra
There's a few awkward printk()s inside of scheduler guts that people prefer to keep but really are rather deadlock prone. Fudge around it by storing the text in a per-cpu buffer and poll it using the existing printk_tick() handler. This will drop output when its more frequent than once a tick, however only the affinity thing could possible go that fast and for that just one should suffice to notify the admin he's done something silly.. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Link: http://lkml.kernel.org/n/tip-wua3lmkt3dg8nfts66o6brne@git.kernel.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-03-12sched/nohz: Correctly initialize 'next_balance' in 'nohz' idle balancerDiwakar Tundlam
The 'next_balance' field of 'nohz' idle balancer must be initialized to jiffies. Since jiffies is initialized to negative 300 seconds the 'nohz' idle balancer does not run for the first 300s (5mins) after bootup. If no new processes are spawed or no idle cycles happen, the load on the cpus will remain unbalanced for that duration. Signed-off-by: Diwakar Tundlam <dtundlam@nvidia.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1DD7BFEDD3147247B1355BEFEFE4665237994F30EF@HQMAIL04.nvidia.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-03-12sched: Cleanup cpu_active madnessPeter Zijlstra
Stepan found: CPU0 CPUn _cpu_up() __cpu_up() boostrap() notify_cpu_starting() set_cpu_online() while (!cpu_active()) cpu_relax() <PREEMPT-out> smp_call_function(.wait=1) /* we find cpu_online() is true */ arch_send_call_function_ipi_mask() /* wait-forever-more */ <PREEMPT-in> local_irq_enable() cpu_notify(CPU_ONLINE) sched_cpu_active() set_cpu_active() Now the purpose of cpu_active is mostly with bringing down a cpu, where we mark it !active to avoid the load-balancer from moving tasks to it while we tear down the cpu. This is required because we only update the sched_domain tree after we brought the cpu-down. And this is needed so that some tasks can still run while we bring it down, we just don't want new tasks to appear. On cpu-up however the sched_domain tree doesn't yet include the new cpu, so its invisible to the load-balancer, regardless of the active state. So instead of setting the active state after we boot the new cpu (and consequently having to wait for it before enabling interrupts) set the cpu active before we set it online and avoid the whole mess. Reported-by: Stepan Moskovchenko <stepanm@codeaurora.org> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1323965362.18942.71.camel@twins Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-03-12sched: Fix load-balance wreckagePeter Zijlstra
Commit 367456c ("sched: Ditch per cgroup task lists for load-balancing") completely wrecked load-balancing due to a few silly mistakes. Correct those and remove more pointless code. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/n/tip-zk04ihygwxn7qqrlpaf73b0r@git.kernel.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-03-12workqueue: use percpu allocator for cwq on UPLai Jiangshan
I notice that the commit bbddff makes percpu allocator can work on UP, So we don't need the magic way for UP. Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2012-03-09Merge commit 'v3.3-rc6' into nextDmitry Torokhov
2012-03-09genirq: Get rid of unnecessary IRQTF_DIED flagAlexander Gordeev
Currently IRQTF_DIED flag is set when a IRQ thread handler calls do_exit() But also PF_EXITING per process flag gets set when a thread exits. This fix eliminates the duplicate by using PF_EXITING flag. Also, there is a race condition in exit_irq_thread(). In case a thread's bit is cleared in desc->threads_oneshot (and the IRQ line gets unmasked), but before IRQTF_DIED flag is set, a new interrupt might come in and set just cleared bit again, this time forever. This fix throws IRQTF_DIED flag away, eliminating the race as a result. [ tglx: Test THREAD_EXITING first as suggested by Oleg ] Reported-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Alexander Gordeev <agordeev@redhat.com> Link: http://lkml.kernel.org/r/20120309135958.GD2114@dhcp-26-207.brq.redhat.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-03-09genirq: No need to check IRQTF_DIED before stopping a thread handlerAlexander Gordeev
Since 63706172f332fd3f6e7458ebfb35fa6de9c21dc5 kthread_stop() is not afraid of dead kernel threads. So no need to check if a thread is alive before stopping it. These checks still were racy. Reported-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Alexander Gordeev <agordeev@redhat.com> Link: http://lkml.kernel.org/r/20120309135939.GC2114@dhcp-26-207.brq.redhat.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-03-09genirq: Get rid of unnecessary irqaction field in task_structAlexander Gordeev
When a new thread handler is created, an irqaction is passed to it as data. Not only that irqaction is stored in task_struct by the handler for later use, but also a structure associated with the kernel thread keeps this value as long as the thread exists. This fix kicks irqaction out off task_struct. Yes, I introduce new bit field. But it allows not only to eliminate the duplicate, but also shortens size of task_struct. Reported-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Alexander Gordeev <agordeev@redhat.com> Link: http://lkml.kernel.org/r/20120309135925.GB2114@dhcp-26-207.brq.redhat.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-03-09genirq: Fix incorrect check for forced IRQ thread handlerAlexander Gordeev
We do not want a bitwise AND between boolean operands Signed-off-by: Alexander Gordeev <agordeev@redhat.com> Cc: Oleg Nesterov <oleg@redhat.com> Link: http://lkml.kernel.org/r/20120309135912.GA2114@dhcp-26-207.brq.redhat.com Cc: stable@vger.kernel.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-03-07Revert "CPU hotplug, cpusets, suspend: Don't touch cpusets during ↵Linus Torvalds
suspend/resume" This reverts commit 8f2f748b0656257153bcf0941df8d6060acc5ca6. It causes some odd regression that we have not figured out, and it's too late in the -rc series to try to figure it out now. As reported by Konstantin Khlebnikov, it causes consistent hangs on his laptop (Thinkpad x220: 2x cores + HT). They can be avoided by adding calls to "rebuild_sched_domains();" in cpuset_cpu_[in]active() for the CPU_{ONLINE/DOWN_FAILED/DOWN_PREPARE}_FROZEN cases, but it's not at all clear why, and it makes no sense. Konstantin's config doesn't even have CONFIG_CPUSETS enabled, just to make things even more interesting. So it's not the cpusets, it's just the scheduling domains. So until this is understood, revert. Bisected-reported-and-tested-by: Konstantin Khlebnikov <khlebnikov@openvz.org> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Ingo Molnar <mingo@elte.hu> Acked-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-06genirq: Clear action->thread_mask if IRQ_ONESHOT is not setThomas Gleixner
Xommit ac5637611(genirq: Unmask oneshot irqs when thread was not woken) fails to unmask when a !IRQ_ONESHOT threaded handler is handled by handle_level_irq. This happens because thread_mask is or'ed unconditionally in irq_wake_thread(), but for !IRQ_ONESHOT interrupts never cleared. So the check for !desc->thread_active fails and keeps the interrupt disabled. Keep the thread_mask zero for !IRQ_ONESHOT interrupts. Document the thread_mask magic while at it. Reported-and-tested-by: Sven Joachim <svenjoac@gmx.de> Reported-and-tested-by: Stefan Lippers-Hollmann <s.l-h@gmx.de> Cc: stable@vger.kernel.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-06softirq: Reduce invoke_softirq() code duplicationHeiko Carstens
The two invoke_softirq() variants are identical except for a single line. So move the #ifdef __ARCH_IRQ_EXIT_IRQS_DISABLED inside one of the functions and get rid of the other one. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-03-06genirq: Fix long-term regression in genirq irq_set_irq_type() handlingRussell King
In 2008, commit 0c5d1eb77a8be ("genirq: record trigger type") modified the way set_irq_type() handles the 'no trigger' condition. However, this has an adverse effect on PCMCIA support on Intel StrongARM and probably PXA platforms. PCMCIA has several status signals on the socket which can trigger interrupts; some of these status signals depend on the card's mode (whether it is configured in memory or IO mode). For example, cards have a 'Ready/IRQ' signal: in memory mode, this provides an indication to PCMCIA that the card has finished its power up initialization. In IO mode, it provides the device interrupt signal. Other status signals switch between on-board battery status and loud speaker output. In classical PCMCIA implementations, where you have a specific socket controller, the controller provides a method to mask interrupts from the socket, and importantly ignore any state transitions on the pins which correspond with interrupts once masked. This masking prevents unwanted events caused by the removal and application of socket power being forwarded. However, on platforms where there is no socket controller, the PCMCIA status and interrupt signals are routed to standard edge-triggered GPIOs. These GPIOs can be configured to interrupt on rising edge, falling edge, or never. This is where the problems start. Edge triggered interrupts are required to record events while disabled via the usual methods of {free,request,disable,enable}_irq() to prevent problems with dropped interrupts (eg, the 8390 driver uses disable_irq() to defer the delivery of interrupts). As a result, these interfaces can not be used to implement the desired behaviour. The side effect of this is that if the 'Ready/IRQ' GPIO is disabled via disable_irq() on suspend, and enabled via enable_irq() after resume, we will record the state transitions caused by powering events as valid interrupts, and foward them to the card driver, which may attempt to access a card which is not powered up. This leads delays resume while drivers spin in their interrupt handlers, and complaints from drivers before they realize what's happened. Moreover, in the case of the 'Ready/IRQ' signal, this is requested and freed by the card driver itself; the PCMCIA core has no idea whether the interrupt is requested, and, therefore, whether a call to disable_irq() would be valid. (We tried this around 2.4.17 / 2.5.1 kernel era, and ended up throwing it out because of this problem.) Therefore, it was decided back in around 2002 to disable the edge triggering instead, resulting in all state transitions on the GPIO being ignored. That's what we actually need the hardware to do. The commit above changes this behaviour; it explicitly prevents the 'no trigger' state being selected. The reason that request_irq() does not accept the 'no trigger' state is for compatibility with existing drivers which do not provide their desired triggering configuration. The set_irq_type() function is 'new' and not used by non-trigger aware drivers. Therefore, revert this change, and restore previously working platforms back to their former state. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Cc: linux@arm.linux.org.uk Cc: Ingo Molnar <mingo@elte.hu> Cc: stable@vger.kernel.org Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-03-05hung_task: fix the broken rcu_lock_break() logicOleg Nesterov
check_hung_uninterruptible_tasks()->rcu_lock_break() introduced by "softlockup: check all tasks in hung_task" commit ce9dbe24 looks absolutely wrong. - rcu_lock_break() does put_task_struct(). If the task has exited it is not safe to even read its ->state, nothing protects this task_struct. - The TASK_DEAD checks are wrong too. Contrary to the comment, we can't use it to check if the task was unhashed. It can be unhashed without TASK_DEAD, or it can be valid with TASK_DEAD. For example, an autoreaping task can do release_task(current) long before it sets TASK_DEAD in do_exit(). Or, a zombie task can have ->state == TASK_DEAD but release_task() was not called, and in this case we must not break the loop. Change this code to check pid_alive() instead, and do this before we drop the reference to the task_struct. Note: while_each_thread() under rcu_read_lock() is not really safe, it can livelock. This will be fixed later, but fortunately in this case the "max_count" logic saves us anyway. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Acked-by: Mandeep Singh Baines <msb@google.com> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-05vfork: kill PF_STARTINGOleg Nesterov
Previously it was (ab)used by utrace. Then it was wrongly used by the scheduler code. Currently it is not used, kill it before it finds the new erroneous user. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-05coredump_wait: don't call complete_vfork_done()Oleg Nesterov
Now that CLONE_VFORK is killable, coredump_wait() no longer needs complete_vfork_done(). zap_threads() should find and kill all tasks with the same ->mm, this includes our parent if ->vfork_done is set. mm_release() becomes the only caller, unexport complete_vfork_done(). Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-05vfork: make it killableOleg Nesterov
Make vfork() killable. Change do_fork(CLONE_VFORK) to do wait_for_completion_killable(). If it fails we do not return to the user-mode and never touch the memory shared with our child. However, in this case we should clear child->vfork_done before return, we use task_lock() in do_fork()->wait_for_vfork_done() and complete_vfork_done() to serialize with each other. Note: now that we use task_lock() we don't really need completion, we could turn task->vfork_done into "task_struct *wake_up_me" but this needs some complications. NOTE: this and the next patches do not affect in-kernel users of CLONE_VFORK, kernel threads run with all signals ignored including SIGKILL/SIGSTOP. However this is obviously the user-visible change. Not only a fatal signal can kill the vforking parent, a sub-thread can do execve or exit_group() and kill the thread sleeping in vfork(). Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-05vfork: introduce complete_vfork_done()Oleg Nesterov
No functional changes. Move the clear-and-complete-vfork_done code into the new trivial helper, complete_vfork_done(). Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-05kprobes: return proper error code from register_kprobe()Prashanth Nageshappa
register_kprobe() aborts if the address of the new request falls in a prohibited area (such as ftrace pouch, __kprobes annotated functions, non-kernel text addresses, jump label text). We however don't return the right error on this abort, resulting in a silent failure - incorrect adding/reporting of kprobes ('perf probe do_fork+18' or 'perf probe mcount' for instance). In V2 we are incorporating Masami Hiramatsu's feedback. This patch fixes it by returning -EINVAL upon failure. While we are here, rename the label used for exit to be more appropriate. Signed-off-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Signed-off-by: Prashanth K Nageshappa <prashanth@linux.vnet.ibm.com> Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Jason Baron <jbaron@redhat.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-05kmsg_dump: don't run on non-error paths by defaultMatthew Garrett
Since commit 04c6862c055f ("kmsg_dump: add kmsg_dump() calls to the reboot, halt, poweroff and emergency_restart paths"), kmsg_dump() gets run on normal paths including poweroff and reboot. This is less than ideal given pstore implementations that can only represent single backtraces, since a reboot may overwrite a stored oops before it's been picked up by userspace. In addition, some pstore backends may have low performance and provide a significant delay in reboot as a result. This patch adds a printk.always_kmsg_dump kernel parameter (which can also be changed from userspace). Without it, the code will only be run on failure paths rather than on normal paths. The option can be enabled in environments where there's a desire to attempt to audit whether or not a reboot was cleanly requested or not. Signed-off-by: Matthew Garrett <mjg@redhat.com> Acked-by: Seiji Aguchi <seiji.aguchi@hds.com> Cc: Seiji Aguchi <seiji.aguchi@hds.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Marco Stornelli <marco.stornelli@gmail.com> Cc: Artem Bityutskiy <Artem.Bityutskiy@nokia.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Don Zickus <dzickus@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-05perf: Add callback to flush branch_stack on context switchStephane Eranian
With branch stack sampling, it is possible to filter by priv levels. In system-wide mode, that means it is possible to capture only user level branches. The builtin SW LBR filter needs to disassemble code based on LBR captured addresses. For that, it needs to know the task the addresses are associated with. Because of context switches, the content of the branch stack buffer may contain addresses from different tasks. We need a callback on context switch to either flush the branch stack or save it. This patch adds a new callback in struct pmu which is called during context switches. The callback is called only when necessary. That is when a system-wide context has, at least, one event which uses PERF_SAMPLE_BRANCH_STACK. The callback is never called for per-thread context. In this version, the Intel x86 code simply flushes (resets) the LBR on context switches (fills it with zeroes). Those zeroed branches are then filtered out by the SW filter. Signed-off-by: Stephane Eranian <eranian@google.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1328826068-11713-11-git-send-email-eranian@google.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-03-05perf: Disable PERF_SAMPLE_BRANCH_* when not supportedStephane Eranian
PERF_SAMPLE_BRANCH_* is disabled for: - SW events (sw counters, tracepoints) - HW breakpoints - ALL but Intel x86 architecture - AMD64 processors Signed-off-by: Stephane Eranian <eranian@google.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1328826068-11713-10-git-send-email-eranian@google.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-03-05perf: Add generic taken branch sampling supportStephane Eranian
This patch adds the ability to sample taken branches to the perf_event interface. The ability to capture taken branches is very useful for all sorts of analysis. For instance, basic block profiling, call counts, statistical call graph. This new capability requires hardware assist and as such may not be available on all HW platforms. On Intel x86 it is implemented on top of the Last Branch Record (LBR) facility. To enable taken branches sampling, the PERF_SAMPLE_BRANCH_STACK bit must be set in attr->sample_type. Sampled taken branches may be filtered by type and/or priv levels. The patch adds a new field, called branch_sample_type, to the perf_event_attr structure. It contains a bitmask of filters to apply to the sampled taken branches. Filters may be implemented in HW. If the HW filter does not exist or is not good enough, some arch may also implement a SW filter. The following generic filters are currently defined: - PERF_SAMPLE_USER only branches whose targets are at the user level - PERF_SAMPLE_KERNEL only branches whose targets are at the kernel level - PERF_SAMPLE_HV only branches whose targets are at the hypervisor level - PERF_SAMPLE_ANY any type of branches (subject to priv levels filters) - PERF_SAMPLE_ANY_CALL any call branches (may incl. syscall on some arch) - PERF_SAMPLE_ANY_RET any return branches (may incl. syscall returns on some arch) - PERF_SAMPLE_IND_CALL indirect call branches Obviously filter may be combined. The priv level bits are optional. If not provided, the priv level of the associated event are used. It is possible to collect branches at a priv level different from the associated event. Use of kernel, hv priv levels is subject to permissions and availability (hv). The number of taken branch records present in each sample may vary based on HW, the type of sampled branches, the executed code. Therefore each sample contains the number of taken branches it contains. Signed-off-by: Stephane Eranian <eranian@google.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1328826068-11713-2-git-send-email-eranian@google.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-03-05Merge branch 'perf/urgent' into perf/coreIngo Molnar
Conflicts: tools/perf/builtin-record.c tools/perf/builtin-top.c tools/perf/perf.h tools/perf/util/top.h Merge reason: resolve these cherry-picking conflicts. Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-03-04Merge branch 'pm-qos'Rafael J. Wysocki
* pm-qos: PM / QoS: unconditionally build the feature PM / QoS: Simplify PM QoS expansion/merge
2012-03-04Merge branch 'pm-sleep'Rafael J. Wysocki
* pm-sleep: PM / Freezer: Remove references to TIF_FREEZE in comments PM / Sleep: Add more wakeup source initialization routines PM / Hibernate: Enable usermodehelpers in hibernate() error path PM / Sleep: Make __pm_stay_awake() delete wakeup source timers PM / Sleep: Fix race conditions related to wakeup source timer function PM / Sleep: Fix possible infinite loop during wakeup source destruction PM / Hibernate: print physical addresses consistently with other parts of kernel PM: Add comment describing relationships between PM callbacks to pm.h PM / Sleep: Drop suspend_stats_update() PM / Sleep: Make enter_state() in kernel/power/suspend.c static PM / Sleep: Unify kerneldoc comments in kernel/power/suspend.c PM / Sleep: Remove unnecessary label from suspend_freeze_processes() PM / Sleep: Do not check wakeup too often in try_to_freeze_tasks() PM / Sleep: Initialize wakeup source locks in wakeup_source_add() PM / Hibernate: Refactor and simplify freezer_test_done PM / Hibernate: Thaw kernel threads in hibernation_snapshot() in error/test path PM / Freezer / Docs: Document the beauty of freeze/thaw semantics PM / Suspend: Avoid code duplication in suspend statistics update PM / Sleep: Introduce generic callbacks for new device PM phases PM / Sleep: Introduce "late suspend" and "early resume" of devices
2012-03-04PM / Freezer: Remove references to TIF_FREEZE in commentsMarcos Paulo de Souza
This patch removes all the references in the code about the TIF_FREEZE flag removed by commit a3201227f803ad7fd43180c5195dbe5a2bf998aa freezer: make freezing() test freeze conditions in effect instead of TIF_FREEZE There still are some references to TIF_FREEZE in Documentation/power/freezing-of-tasks.txt, but it looks like that documentation needs more thorough work to reflect how the new freezer works, and hence merely removing the references to TIF_FREEZE won't really help. So I have not touched that part in this patch. Suggested-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Signed-off-by: Marcos Paulo de Souza <marcos.mage@gmail.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-03-04PM / Hibernate: Enable usermodehelpers in hibernate() error pathSrivatsa S. Bhat
If create_basic_memory_bitmaps() fails, usermodehelpers are not re-enabled before returning. Fix this. And while at it, reword the goto labels so that they look more meaningful. Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Cc: stable@vger.kernel.org Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-03-02Merge branches 'core-urgent-for-linus', 'perf-urgent-for-linus' and ↵Linus Torvalds
'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pulling latest branches from Ingo: * 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: memblock: Fix size aligning of memblock_alloc_base_nid() * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf probe: Ensure offset provided is not greater than function length without DWARF info too perf tools: Ensure comm string is properly terminated perf probe: Ensure offset provided is not greater than function length perf evlist: Return first evsel for non-sample event on old kernel perf/hwbp: Fix a possible memory leak * 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: CPU hotplug, cpusets, suspend: Don't touch cpusets during suspend/resume
2012-03-02sched: Clean up parameter passing of proc_sched_autogroup_set_nice()Hiroshi Shimamoto
Pass nice as a value to proc_sched_autogroup_set_nice(). No side effect is expected, and the variable err will be overwritten with the return value. Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/4F45FBB7.5090607@ct.jp.nec.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-03-02Block: use a freezable workqueue for disk-event pollingAlan Stern
This patch (as1519) fixes a bug in the block layer's disk-events polling. The polling is done by a work routine queued on the system_nrt_wq workqueue. Since that workqueue isn't freezable, the polling continues even in the middle of a system sleep transition. Obviously, polling a suspended drive for media changes and such isn't a good thing to do; in the case of USB mass-storage devices it can lead to real problems requiring device resets and even re-enumeration. The patch fixes things by creating a new system-wide, non-reentrant, freezable workqueue and using it for disk-events polling. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> CC: <stable@kernel.org> Acked-by: Tejun Heo <tj@kernel.org> Acked-by: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-03-01tracing: Keep NMI watchdog from triggering when dumping traceSteven Rostedt
As ftrace_dump() (called by ftrace_dump_on_oops) disables interrupts as it dumps its output to the console, it can keep interrupts disabled for long periods of time. This is likely to trigger the NMI watchdog, and it can disrupt the output of critical data. Add a touch_nmi_watchdog() to each event that is written to the screen to keep the NMI watchdog from affecting the output. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-03-01sched: Ditch per cgroup task lists for load-balancingPeter Zijlstra
Per cgroup load-balance has numerous problems, chief amongst them that there is no real sane order in them. So stop pretending it makes sense and enqueue all tasks on a single list. This also allows us to more easily fix the fwd progress issue uncovered by the lock-break stuff. Rotate the list on failure to migreate and limit the total iterations to nr_running (which with releasing the lock isn't strictly accurate but close enough). Also add a filter that skips very light tasks on the first attempt around the list, this attempts to avoid shooting whole cgroups around without affecting over balance. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: pjt@google.com Link: http://lkml.kernel.org/n/tip-tx8yqydc7eimgq7i4rkc3a4g@git.kernel.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-03-01sched: Rename load-balancing fieldsPeter Zijlstra
s/env->this_/env->dst_/g s/env->busiest_/env->src_/g s/pull_task/move_task/g Makes everything clearer. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: pjt@google.com Link: http://lkml.kernel.org/n/tip-0yvgms8t8x962drpvl0fu0kk@git.kernel.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-03-01sched: Move load-balancing arguments into helper structPeter Zijlstra
Passing large sets of similar arguments all around the load-balancer gets tiresom when you want to modify something. Stick them all in a helper structure and pass the structure around. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: pjt@google.com Link: http://lkml.kernel.org/n/tip-5slqz0vhsdzewrfk9eza1aon@git.kernel.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-03-01sched/rt: Do not submit new work when PI-blockedThomas Gleixner
When we are PI-blocked then we want to get things done ASAP. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/n/tip-vw8et3445km5b8mpihf4trae@git.kernel.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-03-01sched/rt: Prevent idle task boostingThomas Gleixner
Idle task boosting is a nono in general. There is one exception, when PREEMPT_RT and NOHZ is active: The idle task calls get_next_timer_interrupt() and holds the timer wheel base->lock on the CPU and another CPU wants to access the timer (probably to cancel it). We can safely ignore the boosting request, as the idle CPU runs this code with interrupts disabled and will complete the lock protected section without being interrupted. So there is no real need to boost. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/n/tip-755rvsosz7sdzot12a3gbha6@git.kernel.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-03-01sched/wait: Add __wake_up_all_locked() APIThomas Gleixner
For code which protects the waitqueue itself with another lock it makes no sense to acquire the waitqueue lock for wakeup all. Provide __wake_up_all_locked(). This is an optimization on the vanilla kernel (to be used by the PCI code) and an important semantic distinction on -rt. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/n/tip-ux6m4b8jonb9inx8xafh77ds@git.kernel.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-03-01sched/rt: Document scheduler related skip-resched-check sitesThomas Gleixner
Create a distinction between scheduler related preempt_enable_no_resched() calls and the nearly one hundred other places in the kernel that do not want to reschedule, for one reason or another. This distinction matters for -rt, where the scheduler and the non-scheduler preempt models (and checks) are different. For upstream it's purely documentational. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/n/tip-gs88fvx2mdv5psnzxnv575ke@git.kernel.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-03-01sched/rt: Use schedule_preempt_disabled()Thomas Gleixner
Coccinelle based conversion. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/n/tip-24swm5zut3h9c4a6s46x8rws@git.kernel.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-03-01sched/rt: Add schedule_preempt_disabled()Thomas Gleixner
Add helper to get rid of the ever repeating: preempt_enable_no_resched(); schedule(); preempt_disable(); patterns. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/n/tip-wxx7btox7coby6ifv5vzhzgp@git.kernel.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-03-01sched/rt: Do not throttle when PI boostingPeter Zijlstra
When a runqueue has rt_runtime_us = 0 then the only way it can accumulate rt_time is via PI boosting. That causes the runqueue to be throttled and replenishing does not change anything due to rt_runtime_us = 0. So avoid that situation by clearing rt_time and skip the throttling alltogether. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> [ Changelog ] Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/n/tip-7x70cypsotjb4jvcor3edctk@git.kernel.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-03-01sched/rt: Keep period timer ticking when rt throttling is activePeter Zijlstra
When a runqueue is throttled we cannot disable the period timer because that timer is the only way to undo the throttling. We got stale throttling entries when a rq was throttled and then the global sysctl was disabled, which stopped the timer. Signed-off-by: Peter Zijlstra <peterz@infradead.org> [ Added changelog ] Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/n/tip-nuj34q52p6ro7szapuz84i0v@git.kernel.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-03-01Merge branch 'linus' into sched/coreIngo Molnar
Merge reason: we'll queue up dependent patches. Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-02-28includecheck: delete any duplicate instances of module.hPaul Gortmaker
Different tree maintainers picked up independently generated trivial compile fixes based on linux-next testing, resulting in some cases where a file would have got more than one addition of module.h once everything was all merged together. Delete any duplicates so includecheck isn't complaining about anything related to module.h/export.h changes. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2012-02-28static keys: Inline the static_key_enabled() functionJason Baron
In the jump label enabled case, calling static_key_enabled() results in a function call. The function returns the results of a compare, so it really doesn't need the overhead of a full function call. Let's make it 'static inline' for both the jump label enabled and disabled cases. Signed-off-by: Jason Baron <jbaron@redhat.com> Cc: a.p.zijlstra@chello.nl Cc: rostedt@goodmis.org Cc: mathieu.desnoyers@polymtl.ca Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/201202281849.q1SIn1p2023270@int-mx10.intmail.prod.int.phx2.redhat.com Signed-off-by: Ingo Molnar <mingo@elte.hu>