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2013-08-14nohz: Optimize full dynticks's sched hooks with static keysFrederic Weisbecker
Scheduler IPIs and task context switches are serious fast path. Let's try to hide as much as we can the impact of full dynticks APIs' off case that are called on these sites through the use of static keys. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Li Zhong <zhong@linux.vnet.ibm.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Kevin Hilman <khilman@linaro.org>
2013-08-14nohz: Optimize full dynticks state checks with static keysFrederic Weisbecker
These APIs are frequenctly accessed and priority is given to optimize the full dynticks off-case in order to let distros enable this feature without suffering from significant performance regressions. Let's inline these APIs and optimize them with static keys. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Li Zhong <zhong@linux.vnet.ibm.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Kevin Hilman <khilman@linaro.org>
2013-08-14nohz: Rename a few state variablesFrederic Weisbecker
Rename the full dynticks's cpumask and cpumask state variables to some more exportable names. These will be used later from global headers to optimize the main full dynticks APIs in conjunction with static keys. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Li Zhong <zhong@linux.vnet.ibm.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Kevin Hilman <khilman@linaro.org>
2013-08-14vtime: Always debug check snapshot source _before_ updating itFrederic Weisbecker
The vtime delta update performed by get_vtime_delta() always check that the source of the snapshot is valid. Meanhile the snapshot updaters that rely on get_vtime_delta() also set the new snapshot origin. But some of them do this right before the call to get_vtime_delta(), making its debug check useless. This is easily fixable by moving the snapshot origin update after the call to get_vtime_delta(). The order doesn't matter there. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Li Zhong <zhong@linux.vnet.ibm.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Kevin Hilman <khilman@linaro.org>
2013-08-14vtime: Always scale generic vtime accounting resultsFrederic Weisbecker
The cputime accounting in full dynticks can be a subtle mixup of CPUs using tick based accounting and others using generic vtime. As long as the tick can have a share on producing these stats, we want to scale the result against CFS precise accounting as the tick can miss some task hiding between the periodic interrupt. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Li Zhong <zhong@linux.vnet.ibm.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Kevin Hilman <khilman@linaro.org>
2013-08-14vtime: Optimize full dynticks accounting off case with static keysFrederic Weisbecker
If no CPU is in the full dynticks range, we can avoid the full dynticks cputime accounting through generic vtime along with its overhead and use the traditional tick based accounting instead. Let's do this and nope the off case with static keys. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Li Zhong <zhong@linux.vnet.ibm.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Kevin Hilman <khilman@linaro.org>
2013-08-14vtime: Describe overriden functions in dedicated arch headersFrederic Weisbecker
If the arch overrides some generic vtime APIs, let it describe these on a dedicated and standalone header. This way it becomes convenient to include it in vtime generic headers without irrelevant stuff in such a low level header. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Li Zhong <zhong@linux.vnet.ibm.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Kevin Hilman <khilman@linaro.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
2013-08-14m68k: hardirq_count() only need preempt_mask.hFrederic Weisbecker
The m68k irqflags implementation needs to check hardirq context in some cases. As it is a very low level header file, it's better to include preempt_mask.h rather than hardirq.h when the only purpose is to use irq context APIs. This way we can avoid future header circular dependencies when vtime.h will expand to use static keys. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Li Zhong <zhong@linux.vnet.ibm.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Kevin Hilman <khilman@linaro.org> Cc: Geert Uytterhoeven <geert@linux-m68k.org>
2013-08-14hardirq: Split preempt count mask definitionsFrederic Weisbecker
In order to use static keys with vtime APIs, we'll need to add static keys headers to vtime.h hardirq.h then becomes a problem because it needs vtime.h for irqtime accounting in irq_enter/irq_exit, but it's often included just to get the irq mask definitions in the task preempt_count field and the APIs that come along: in_interrupt(), in_hardirq(), etc... Some very low level arch headers sometimes need these masks and APIs such as arch/m68k/include/asm/irqflags.h for example. But they don't want to include hardirq.h if vtime.h, jump_label.h and even workqueue.h come along. Including such bloated high level header from arch headers can quickly result in circular headers dependency that crash the build. So let's split hardirq.h in two parts: * preempt_mask.h that gathers all the preempt_count definitions and the APIs associated. This one is considered low level and can be safely included anywhere. * hardirq.h that includes the previous one. It defines the irq entry/exit APIs. To avoid future circular headers dependencies, the preempt_mask.h inclusion can replace hardirq.h on files that don't implement irq low level handlers but just need the atomic/context check APIs. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Li Zhong <zhong@linux.vnet.ibm.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Kevin Hilman <khilman@linaro.org>
2013-08-14context_tracking: Split low level state headersFrederic Weisbecker
We plan to use the context tracking static key on inline vtime APIs. For this we need to include the context tracking headers from those of vtime. However vtime headers need to stay low level because they are included in hardirq.h that mostly contains standalone definitions. But context_tracking.h includes sched.h for a few task_struct references, therefore it wouldn't be sensible to include it from vtime.h To solve this, lets split the context tracking headers and move out the pure state definitions that only require a few low level headers. We can safely include that small part in vtime.h later. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Li Zhong <zhong@linux.vnet.ibm.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Kevin Hilman <khilman@linaro.org>
2013-08-14vtime: Fix racy cputime delta updateFrederic Weisbecker
get_vtime_delta() must be called under the task vtime_seqlock with the code that does the cputime accounting flush. Otherwise the cputime reader can be fooled and run into a race where it sees the snapshot update but misses the cputime flush. As a result it can report a cputime that is way too short. Fix vtime_account_user() that wasn't complying to that rule. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Li Zhong <zhong@linux.vnet.ibm.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Kevin Hilman <khilman@linaro.org>
2013-08-14vtime: Remove a few unneeded generic vtime state checksFrederic Weisbecker
Some generic vtime APIs check if the vtime accounting is enabled on the local CPU before doing their work. Some of these are not needed because all their callers already take care of that. Let's remove the checks on these. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Li Zhong <zhong@linux.vnet.ibm.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Kevin Hilman <khilman@linaro.org>
2013-08-14context_tracking: User/kernel broundary cross trace eventsFrederic Weisbecker
This can be useful to track all kernel/user round trips. And it's also helpful to debug the context tracking subsystem. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Li Zhong <zhong@linux.vnet.ibm.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Kevin Hilman <khilman@linaro.org>
2013-08-14context_tracking: Optimize context switch off case with static keysFrederic Weisbecker
No need for syscall slowpath if no CPU is full dynticks, rather nop this in this case. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Li Zhong <zhong@linux.vnet.ibm.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Kevin Hilman <khilman@linaro.org>
2013-08-14context_tracking: Optimize guest APIs off case with static keyFrederic Weisbecker
Optimize guest entry/exit APIs with static keys. This minimize the overhead for those who enable CONFIG_NO_HZ_FULL without always using it. Having no range passed to nohz_full= should result in the probes overhead to be minimized. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Li Zhong <zhong@linux.vnet.ibm.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Kevin Hilman <khilman@linaro.org>
2013-08-14context_tracking: Optimize main APIs off case with static keyFrederic Weisbecker
Optimize user and exception entry/exit APIs with static keys. This minimize the overhead for those who enable CONFIG_NO_HZ_FULL without always using it. Having no range passed to nohz_full= should result in the probes to be nopped (at least we hope so...). If this proves not be enough in the long term, we'll need to bring an exception slow path by re-routing the exception handlers. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Li Zhong <zhong@linux.vnet.ibm.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Kevin Hilman <khilman@linaro.org>
2013-08-14context_tracking: Ground setup for static key useFrederic Weisbecker
Prepare for using a static key in the context tracking subsystem. This will help optimizing the off case on its many users: * user_enter, user_exit, exception_enter, exception_exit, guest_enter, guest_exit, vtime_*() Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Li Zhong <zhong@linux.vnet.ibm.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Kevin Hilman <khilman@linaro.org>
2013-08-13context_tracking: Remove full dynticks' hacky dependency on wide context ↵Frederic Weisbecker
tracking Now that the full dynticks subsystem only enables the context tracking on full dynticks CPUs, lets remove the dependency on CONTEXT_TRACKING_FORCE This dependency was a hack to enable the context tracking widely for the full dynticks susbsystem until the latter becomes able to enable it in a more CPU-finegrained fashion. Now CONTEXT_TRACKING_FORCE only stands for testing on archs that work on support for the context tracking while full dynticks can't be used yet due to unmet dependencies. It simulates a system where all CPUs are full dynticks so that RCU user extended quiescent states and dynticks cputime accounting can be tested on the given arch. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Li Zhong <zhong@linux.vnet.ibm.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Kevin Hilman <khilman@linaro.org>
2013-08-13nohz: Only enable context tracking on full dynticks CPUsFrederic Weisbecker
The context tracking subsystem has the ability to selectively enable the tracking on any defined subset of CPU. This means that we can define a CPU range that doesn't run the context tracking and another range that does. Now what we want in practice is to enable the tracking on full dynticks CPUs only. In order to perform this, we just need to pass our full dynticks CPU range selection from the full dynticks subsystem to the context tracking. This way we can spare the overhead of RCU user extended quiescent state and vtime maintainance on the CPUs that are outside the full dynticks range. Just keep in mind the raw context tracking itself is still necessary everywhere. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Li Zhong <zhong@linux.vnet.ibm.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Kevin Hilman <khilman@linaro.org>
2013-08-13context_tracking: Fix runtime CPU off-caseFrederic Weisbecker
As long as the context tracking is enabled on any CPU, even a single one, all other CPUs need to keep track of their user <-> kernel boundaries cross as well. This is because a task can sleep while servicing an exception that happened in the kernel or in userspace. Then when the task eventually wakes up and return from the exception, the CPU needs to know if we resume in userspace or in the kernel. exception_exit() get this information from exception_enter() that saved the previous state. If the CPU where the exception happened didn't keep track of these informations, exception_exit() doesn't know which state tracking to restore on the CPU where the task got migrated and we may return to userspace with the context tracking subsystem thinking that we are in kernel mode. This can be fixed in the long term if we move our context tracking probes on very low level arch fast path user <-> kernel boundary, although even that is worrisome as an exception can still happen in the few instructions between the probe and the actual iret. Also we are not yet ready to set these probes in the fast path given the potential overhead problem it induces. So let's fix this by always enable context tracking even on CPUs that are not in the full dynticks range. OTOH we can spare the rcu_user_*() and vtime_user_*() calls there because the tick runs on these CPUs and we can handle RCU state machine and cputime accounting through it. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Li Zhong <zhong@linux.vnet.ibm.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Kevin Hilman <khilman@linaro.org>
2013-08-13vtime: Update a few commentsFrederic Weisbecker
Update a stale comment from the old vtime era and document some locking that might be non obvious. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Li Zhong <zhong@linux.vnet.ibm.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Kevin Hilman <khilman@linaro.org>
2013-08-13context_tracing: Fix guest accounting with native vtimeFrederic Weisbecker
1) If context tracking is enabled with native vtime accounting (which combo is useless except for dev testing), we call vtime_guest_enter() and vtime_guest_exit() on host <-> guest switches. But those are stubs in this configurations. As a result, cputime is not correctly flushed on kvm context switches. 2) If context tracking runs but is disabled on some CPUs, those CPUs end up calling __guest_enter/__guest_exit which in turn call vtime_account_system(). We don't want to call this because we run in tick based accounting for these CPUs. Refactor the guest_enter/guest_exit code such that all combinations finally work. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Li Zhong <zhong@linux.vnet.ibm.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Kevin Hilman <khilman@linaro.org>
2013-08-13sched: Consolidate open coded preemptible() checksFrederic Weisbecker
preempt_schedule() and preempt_schedule_context() open code their preemptability checks. Use the standard API instead for consolidation. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Li Zhong <zhong@linux.vnet.ibm.com> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Alex Shi <alex.shi@intel.com> Cc: Paul Turner <pjt@google.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Vincent Guittot <vincent.guittot@linaro.org>
2013-08-12Merge branch 'fortglx/3.11/time' of ↵Ingo Molnar
git://git.linaro.org/people/jstultz/linux into timers/urgent Pull small fix for v3.11 from John Stultz. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-07-25Merge branch 'timers/urgent' of ↵Ingo Molnar
git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks into timers/urgent Pull nohz fixes from Frederic Weisbecker. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-07-24nohz: fix compile warning in tick_nohz_init()Li Zhong
cpu is not used after commit 5b8621a68fdcd2baf1d3b413726f913a5254d46a Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Li Zhong <zhong@linux.vnet.ibm.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Kevin Hilman <khilman@linaro.org> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2013-07-24nohz: Do not warn about unstable tsc unless user uses nohz_fullSteven Rostedt
If the user enables CONFIG_NO_HZ_FULL and runs the kernel on a machine with an unstable TSC, it will produce a WARN_ON dump as well as taint the kernel. This is a bit extreme for a kernel that just enables a feature but doesn't use it. The warning should only happen if the user tries to use the feature by either adding nohz_full to the kernel command line, or by enabling CONFIG_NO_HZ_FULL_ALL that makes nohz used on all CPUs at boot up. Note, this second feature should not (yet) be used by distros or anyone that doesn't care if NO_HZ is used or not. Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Li Zhong <zhong@linux.vnet.ibm.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Kevin Hilman <khilman@linaro.org> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2013-07-22Merge tag 'trace-3.11-rc2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing fixes and cleanups from Steven Rostedt: "This contains fixes, optimizations and some clean ups Some of the fixes need to go back to 3.10. They are minor, and deal mostly with incorrect ref counting in accessing event files. There was a couple of optimizations that should have perf perform a bit better when accessing trace events. And some various clean ups. Some of the clean ups are necessary to help in a fix to a theoretical race between opening a event file and deleting that event" * tag 'trace-3.11-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: tracing: Kill the unbalanced tr->ref++ in tracing_buffers_open() tracing: Kill trace_array->waiter tracing: Do not (ab)use trace_seq in event_id_read() tracing: Simplify the iteration logic in f_start/f_next tracing: Add ref_data to function and fgraph tracer structs tracing: Miscellaneous fixes for trace_array ref counting tracing: Fix error handling to ensure instances can always be removed tracing/kprobe: Wait for disabling all running kprobe handlers tracing/perf: Move the PERF_MAX_TRACE_SIZE check into perf_trace_buf_prepare() tracing/syscall: Avoid perf_trace_buf_*() if sys_data->perf_events is empty tracing/function: Avoid perf_trace_buf_*() if event_function.perf_events is empty tracing: Typo fix on ring buffer comments tracing: Use trace_seq_puts()/trace_seq_putc() where possible tracing: Use correct config guard CONFIG_STACK_TRACER
2013-07-22Merge branch 'next' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux Pull thermal management fixes from Zhang Rui: "These are fixes collected over the last week, they fixes several problems caused by the x86_pkg_temp_thermal introduced in 3.11-rc1. Specifics: - the x86_pkg_temp_thermal driver causes crash on systems with no package MSR support as there is a bug in the logic to check presence of DTHERM and PTS feature together. Added a change so that when there is no PTS support, module doesn't get loaded. - fix krealloc() misuse in pkg_temp_thermal_device_add(). If krealloc() returns NULL, it doesn't free the original. Thus if we want to exit because of the krealloc() failure, we must make sure the original one is freed. - The error code path of the x86 package temperature thermal driver's initialization routine makes an unbalanced call to get_online_cpus(), which causes subsequent CPU offline operations, and consequently system suspend, to permanently block in cpu_hotplug_begin() on systems where get_core_online() returns an error code. Remove the extra get_online_cpus() to fix the problem" * 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux: Thermal: Fix lockup of cpu_down() Thermal: x86_pkg_temp: Limit number of pkg temp zones Thermal: x86_pkg_temp: fix krealloc() misuse in in pkg_temp_thermal_device_add() Thermal: x86 package temp thermal crash
2013-07-22Merge tag 'gpio-for-v3.11-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio Pull gpio fixes from Linus Walleij: "A first round of GPIO fixes for the v3.11 series: - OMAP device tree boot fix - Handle an error condition in the MSM driver The OMAP patches have been around since around the merge window, but since they first caused more breakage I let them boil in -next for a while. These should be fine now" * tag 'gpio-for-v3.11-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: drivers: gpio: msm: Fix the error condition for reading ngpio gpio/omap: fix build error when OF_GPIO is not defined. gpio/omap: auto request GPIO as input if used as IRQ via DT gpio/omap: don't create an IRQ mapping for every GPIO on DT
2013-07-22Merge branch 'for-3.11/drivers' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull block IO driver bits from Jens Axboe: "As I mentioned in the core block pull request, due to real life circumstances the driver pull request would be late. Now it looks like -rc2 late... On the plus side, apart form the rsxx update, these are all things that I could argue could go in later in the cycle as they are fixes and not features. So even though things are late, it's not ALL bad. The pull request contains: - Updates to bcache, all bug fixes, from Kent. - A pile of drbd bug fixes (no big features this time!). - xen blk front/back fixes. - rsxx driver updates, some of them deferred form 3.10. So should be well cooked by now" * 'for-3.11/drivers' of git://git.kernel.dk/linux-block: (63 commits) bcache: Allocation kthread fixes bcache: Fix GC_SECTORS_USED() calculation bcache: Journal replay fix bcache: Shutdown fix bcache: Fix a sysfs splat on shutdown bcache: Advertise that flushes are supported bcache: check for allocation failures bcache: Fix a dumb race bcache: Use standard utility code bcache: Update email address bcache: Delete fuzz tester bcache: Document shrinker reserve better bcache: FUA fixes drbd: Allow online change of al-stripes and al-stripe-size drbd: Constants should be UPPERCASE drbd: Ignore the exit code of a fence-peer handler if it returns too late drbd: Fix rcu_read_lock balance on error path drbd: fix error return code in drbd_init() drbd: Do not sleep inside rcu bcache: Refresh usage docs ...
2013-07-22sched_clock: Fix integer overflowBaruch Siach
The expression '(1 << 32)' happens to evaluate as 0 on ARM, but it evaluates as 1 on xtensa and x86_64. This zeros sched_clock_mask, and breaks sched_clock(). Set the type of 1 to 'unsigned long long' to get the value we need. Reported-by: Max Filippov <jcmvbkbc@gmail.com> Tested-by: Max Filippov <jcmvbkbc@gmail.com> Acked-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Baruch Siach <baruch@tkos.co.il> Signed-off-by: John Stultz <john.stultz@linaro.org>
2013-07-22Thermal: Fix lockup of cpu_down()Steven Rostedt
Commit f1a18a105 "Thermal: CPU Package temperature thermal" had code that did a get_online_cpus(), run a loop and then do a put_online_cpus(). The problem is that the loop had an error exit that would skip the put_online_cpus() part. In the error exit part of the function, it also did a get_online_cpus(), run a loop and then put_online_cpus(). The only way to get to the error exit part is with get_online_cpus() already performed. If this error condition is hit, the system will be prevented from taking CPUs offline. The process taking the CPU offline will lock up hard. Removing the get_online_cpus() removes the lockup as the hotplug CPU refcount is back to zero. This was bisected with ktest. Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Zhang Rui <rui.zhang@intel.com>
2013-07-21Linux 3.11-rc2Linus Torvalds
2013-07-21Merge tag 'acpi-video-3.11' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull ACPI video support fixes from Rafael Wysocki: "I'm sending a separate pull request for this as it may be somewhat controversial. The breakage addressed here is not really new and the fixes may not satisfy all users of the affected systems, but we've had so much back and forth dance in this area over the last several weeks that I think it's time to actually make some progress. The source of the problem is that about a year ago we started to tell BIOSes that we're compatible with Windows 8, which we really need to do, because some systems shipping with Windows 8 are tested with it and nothing else, so if we tell their BIOSes that we aren't compatible with Windows 8, we expose our users to untested BIOS/AML code paths. However, as it turns out, some Windows 8-specific AML code paths are not tested either, because Windows 8 actually doesn't use the ACPI methods containing them, so if we declare Windows 8 compatibility and attempt to use those ACPI methods, things break. That occurs mostly in the backlight support area where in particular the _BCM and _BQC methods are plain unusable on some systems if the OS declares Windows 8 compatibility. [ The additional twist is that they actually become usable if the OS says it is not compatible with Windows 8, but that may cause problems to show up elsewhere ] Investigation carried out by Matthew Garrett indicates that what Windows 8 does about backlight is to leave backlight control up to individual graphics drivers. At least there's evidence that it does that if the Intel graphics driver is used, so we've decided to follow Windows 8 in that respect and allow i915 to control backlight (Daniel likes that part). The first commit from Aaron Lu makes ACPICA export the variable from which we can infer whether or not the BIOS believes that we are compatible with Windows 8. The second commit from Matthew Garrett prepares the ACPI video driver by making it initialize the ACPI backlight even if it is not going to be used afterward (that is needed for backlight control to work on Thinkpads). The third commit implements the actual workaround making i915 take over backlight control if the firmware thinks it's dealing with Windows 8 and is based on the work of multiple developers, including Matthew Garrett, Chun-Yi Lee, Seth Forshee, and Aaron Lu. The final commit from Aaron Lu makes us follow Windows 8 by informing the firmware through the _DOS method that it should not carry out automatic brightness changes, so that brightness can be controlled by GUI. Hopefully, this approach will allow us to avoid using blacklists of systems that should not declare Windows 8 compatibility just to avoid backlight control problems in the future. - Change from Aaron Lu makes ACPICA export a variable which can be used by driver code to determine whether or not the BIOS believes that we are compatible with Windows 8. - Change from Matthew Garrett makes the ACPI video driver initialize the ACPI backlight even if it is not going to be used afterward (that is needed for backlight control to work on Thinkpads). - Fix from Rafael J Wysocki implements Windows 8 backlight support workaround making i915 take over bakclight control if the firmware thinks it's dealing with Windows 8. Based on the work of multiple developers including Matthew Garrett, Chun-Yi Lee, Seth Forshee, and Aaron Lu. - Fix from Aaron Lu makes the kernel follow Windows 8 by informing the firmware through the _DOS method that it should not carry out automatic brightness changes, so that brightness can be controlled by GUI" * tag 'acpi-video-3.11' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: ACPI / video: no automatic brightness changes by win8-compatible firmware ACPI / video / i915: No ACPI backlight if firmware expects Windows 8 ACPI / video: Always call acpi_video_init_brightness() on init ACPICA: expose OSI version
2013-07-20Merge tag 'ext4_for_linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 Pull ext[34] tmpfile bugfix from Ted Ts'o: "Fix regression caused by commit af51a2ac36d1f which added ->tmpfile() support (along with a similar fix for ext3)" * tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: ext3: fix a BUG when opening a file with O_TMPFILE flag ext4: fix a BUG when opening a file with O_TMPFILE flag
2013-07-20ext3: fix a BUG when opening a file with O_TMPFILE flagZheng Liu
When we try to open a file with O_TMPFILE flag, we will trigger a bug. The root cause is that in ext4_orphan_add() we check ->i_nlink == 0 and this check always fails because we set ->i_nlink = 1 in inode_init_always(). We can use the following program to trigger it: int main(int argc, char *argv[]) { int fd; fd = open(argv[1], O_TMPFILE, 0666); if (fd < 0) { perror("open "); return -1; } close(fd); return 0; } The oops message looks like this: kernel: kernel BUG at fs/ext3/namei.c:1992! kernel: invalid opcode: 0000 [#1] SMP kernel: Modules linked in: ext4 jbd2 crc16 cpufreq_ondemand ipv6 dm_mirror dm_region_hash dm_log dm_mod parport_pc parport serio_raw sg dcdbas pcspkr i2c_i801 ehci_pci ehci_hcd button acpi_cpufreq mperf e1000e ptp pps_core ttm drm_kms_helper drm hwmon i2c_algo_bit i2c_core ext3 jbd sd_mod ahci libahci libata scsi_mod uhci_hcd kernel: CPU: 0 PID: 2882 Comm: tst_tmpfile Not tainted 3.11.0-rc1+ #4 kernel: Hardware name: Dell Inc. OptiPlex 780 /0V4W66, BIOS A05 08/11/2010 kernel: task: ffff880112d30050 ti: ffff8801124d4000 task.ti: ffff8801124d4000 kernel: RIP: 0010:[<ffffffffa00db5ae>] [<ffffffffa00db5ae>] ext3_orphan_add+0x6a/0x1eb [ext3] kernel: RSP: 0018:ffff8801124d5cc8 EFLAGS: 00010202 kernel: RAX: 0000000000000000 RBX: ffff880111510128 RCX: ffff8801114683a0 kernel: RDX: 0000000000000000 RSI: ffff880111510128 RDI: ffff88010fcf65a8 kernel: RBP: ffff8801124d5d18 R08: 0080000000000000 R09: ffffffffa00d3b7f kernel: R10: ffff8801114683a0 R11: ffff8801032a2558 R12: 0000000000000000 kernel: R13: ffff88010fcf6800 R14: ffff8801032a2558 R15: ffff8801115100d8 kernel: FS: 00007f5d172b5700(0000) GS:ffff880117c00000(0000) knlGS:0000000000000000 kernel: CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b kernel: CR2: 00007f5d16df15d0 CR3: 0000000110b1d000 CR4: 00000000000407f0 kernel: Stack: kernel: 000000000000000c ffff8801048a7dc8 ffff8801114685a8 ffffffffa00b80d7 kernel: ffff8801124d5e38 ffff8801032a2558 ffff88010ce24d68 0000000000000000 kernel: ffff88011146b300 ffff8801124d5d44 ffff8801124d5d78 ffffffffa00db7e1 kernel: Call Trace: kernel: [<ffffffffa00b80d7>] ? journal_start+0x8c/0xbd [jbd] kernel: [<ffffffffa00db7e1>] ext3_tmpfile+0xb2/0x13b [ext3] kernel: [<ffffffff821076f8>] path_openat+0x11f/0x5e7 kernel: [<ffffffff821c86b4>] ? list_del+0x11/0x30 kernel: [<ffffffff82065fa2>] ? __dequeue_entity+0x33/0x38 kernel: [<ffffffff82107cd5>] do_filp_open+0x3f/0x8d kernel: [<ffffffff82112532>] ? __alloc_fd+0x50/0x102 kernel: [<ffffffff820f9296>] do_sys_open+0x13b/0x1cd kernel: [<ffffffff820f935c>] SyS_open+0x1e/0x20 kernel: [<ffffffff82398c02>] system_call_fastpath+0x16/0x1b kernel: Code: 39 c7 0f 85 67 01 00 00 0f b7 03 25 00 f0 00 00 3d 00 40 00 00 74 18 3d 00 80 00 00 74 11 3d 00 a0 00 00 74 0a 83 7b 48 00 74 04 <0f> 0b eb fe 49 8b 85 50 03 00 00 4c 89 f6 48 c7 c7 c0 99 0e a0 kernel: RIP [<ffffffffa00db5ae>] ext3_orphan_add+0x6a/0x1eb [ext3] kernel: RSP <ffff8801124d5cc8> Here we couldn't call clear_nlink() directly because in d_tmpfile() we will call inode_dec_link_count() to decrease ->i_nlink. So this commit tries to call d_tmpfile() before ext4_orphan_add() to fix this problem. Signed-off-by: Zheng Liu <wenqing.lz@taobao.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Cc: Jan Kara <jack@suse.cz> Cc: Al Viro <viro@zeniv.linux.org.uk>
2013-07-20ext4: fix a BUG when opening a file with O_TMPFILE flagZheng Liu
When we try to open a file with O_TMPFILE flag, we will trigger a bug. The root cause is that in ext4_orphan_add() we check ->i_nlink == 0 and this check always fails because we set ->i_nlink = 1 in inode_init_always(). We can use the following program to trigger it: int main(int argc, char *argv[]) { int fd; fd = open(argv[1], O_TMPFILE, 0666); if (fd < 0) { perror("open "); return -1; } close(fd); return 0; } The oops message looks like this: kernel BUG at fs/ext4/namei.c:2572! invalid opcode: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC Modules linked in: dlci bridge stp hidp cmtp kernelcapi l2tp_ppp l2tp_netlink l2tp_core sctp libcrc32c rfcomm tun fuse nfnetli nk can_raw ipt_ULOG can_bcm x25 scsi_transport_iscsi ipx p8023 p8022 appletalk phonet psnap vmw_vsock_vmci_transport af_key vmw_vmci rose vsock atm can netrom ax25 af_rxrpc ir da pppoe pppox ppp_generic slhc bluetooth nfc rfkill rds caif_socket caif crc_ccitt af_802154 llc2 llc snd_hda_codec_realtek snd_hda_intel snd_hda_codec serio_raw snd_pcm pcsp kr edac_core snd_page_alloc snd_timer snd soundcore r8169 mii sr_mod cdrom pata_atiixp radeon backlight drm_kms_helper ttm CPU: 1 PID: 1812571 Comm: trinity-child2 Not tainted 3.11.0-rc1+ #12 Hardware name: Gigabyte Technology Co., Ltd. GA-MA78GM-S2H/GA-MA78GM-S2H, BIOS F12a 04/23/2010 task: ffff88007dfe69a0 ti: ffff88010f7b6000 task.ti: ffff88010f7b6000 RIP: 0010:[<ffffffff8125ce69>] [<ffffffff8125ce69>] ext4_orphan_add+0x299/0x2b0 RSP: 0018:ffff88010f7b7cf8 EFLAGS: 00010202 RAX: 0000000000000000 RBX: ffff8800966d3020 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffff88007dfe70b8 RDI: 0000000000000001 RBP: ffff88010f7b7d40 R08: ffff880126a3c4e0 R09: ffff88010f7b7ca0 R10: 0000000000000000 R11: 0000000000000000 R12: ffff8801271fd668 R13: ffff8800966d2f78 R14: ffff88011d7089f0 R15: ffff88007dfe69a0 FS: 00007f70441a3740(0000) GS:ffff88012a800000(0000) knlGS:00000000f77c96c0 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000002834000 CR3: 0000000107964000 CR4: 00000000000007e0 DR0: 0000000000780000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Stack: 0000000000002000 00000020810b6dde 0000000000000000 ffff88011d46db00 ffff8800966d3020 ffff88011d7089f0 ffff88009c7f4c10 ffff88010f7b7f2c ffff88007dfe69a0 ffff88010f7b7da8 ffffffff8125cfac ffff880100000004 Call Trace: [<ffffffff8125cfac>] ext4_tmpfile+0x12c/0x180 [<ffffffff811cba78>] path_openat+0x238/0x700 [<ffffffff8100afc4>] ? native_sched_clock+0x24/0x80 [<ffffffff811cc647>] do_filp_open+0x47/0xa0 [<ffffffff811db73f>] ? __alloc_fd+0xaf/0x200 [<ffffffff811ba2e4>] do_sys_open+0x124/0x210 [<ffffffff81010725>] ? syscall_trace_enter+0x25/0x290 [<ffffffff811ba3ee>] SyS_open+0x1e/0x20 [<ffffffff816ca8d4>] tracesys+0xdd/0xe2 [<ffffffff81001001>] ? start_thread_common.constprop.6+0x1/0xa0 Code: 04 00 00 00 89 04 24 31 c0 e8 c4 77 04 00 e9 43 fe ff ff 66 25 00 d0 66 3d 00 80 0f 84 0e fe ff ff 83 7b 48 00 0f 84 04 fe ff ff <0f> 0b 49 8b 8c 24 50 07 00 00 e9 88 fe ff ff 0f 1f 84 00 00 00 Here we couldn't call clear_nlink() directly because in d_tmpfile() we will call inode_dec_link_count() to decrease ->i_nlink. So this commit tries to call d_tmpfile() before ext4_orphan_add() to fix this problem. Reported-by: Dave Jones <davej@redhat.com> Signed-off-by: Zheng Liu <wenqing.lz@taobao.com> Tested-by: Darrick J. Wong <darrick.wong@oracle.com> Tested-by: Dave Jones <davej@redhat.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Acked-by: Al Viro <viro@zeniv.linux.org.uk>
2013-07-20Merge tag 'staging-3.11-rc2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging Pull staging tree fixes from Greg KH: "Here are a few iio driver fixes for 3.11-rc2. They are still spread across drivers/iio and drivers/staging/iio so they are coming in through this tree. I've also removed the drivers/staging/csr/ driver as the developers who originally sent it to me have moved on to other companies, and CSR still will not send us the specs for the device, making the driver pretty much obsolete and impossible to fix up. Deleting it now prevents people from sending in lots of tiny codingsyle fixes that will never go anywhere. It also helps to offset the large lustre filesystem merge that happened in 3.11-rc1 in the overall 3.11.0 diffstat. :)" * tag 'staging-3.11-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: staging: csr: remove driver iio: lps331ap: Fix wrong in_pressure_scale output value iio staging: fix lis3l02dq, read error handling staging:iio:ad7291: add missing .driver_module to struct iio_info iio: ti_am335x_adc: add missing .driver_module to struct iio_info iio: mxs-lradc: Remove useless check in read_raw iio: mxs-lradc: Fix misuse of iio->trig iio: inkern: fix iio_convert_raw_to_processed_unlocked iio: Fix iio_channel_has_info iio:trigger: device_unregister->device_del to avoid double free iio: dac: ad7303: fix error return code in ad7303_probe()
2013-07-20drivers: gpio: msm: Fix the error condition for reading ngpioRohit Vaswani
of_property_read_u32 return 0 on success. The check was using a ! to return error. Fix the if condition. Signed-off-by: Rohit Vaswani <rvaswani@codeaurora.org> Acked-by: Linus Walleij <linus.walleij@linaro.org> Reviewed-by: Pankaj Jangra <jangra.pankaj9@gmail.com> Cc: "Bird, Tim" <Tim.Bird@sonymobile.com> Signed-off-by: David Brown <davidb@codeaurora.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-07-20Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs fixes from Al Viro: "The sget() one is a long-standing bug and will need to go into -stable (in fact, it had been originally caught in RHEL6), the other two are 3.11-only" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: vfs: constify dentry parameter in d_count() livelock avoidance in sget() allow O_TMPFILE to work with O_WRONLY
2013-07-20Merge tag 'ext4_for_linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 Pull ext4 bugfixes from Ted Ts'o: "Fixes for 3.11-rc2, sent at 5pm, in the professoinal style. :-)" I'm not sure I like this new level of "professionalism". 9-5, people, 9-5. * tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: ext4: call ext4_es_lru_add() after handling cache miss ext4: yield during large unlinks ext4: make the extent_status code more robust against ENOMEM failures ext4: simplify calculation of blocks to free on error ext4: fix error handling in ext4_ext_truncate()
2013-07-20Merge tag 'nfs-for-3.11-3' of git://git.linux-nfs.org/projects/trondmy/linux-nfsLinus Torvalds
Pull NFS client bugfixes from Trond Myklebust: - Fix a regression against NFSv4 FreeBSD servers when creating a new file - Fix another regression in rpc_client_register() * tag 'nfs-for-3.11-3' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: NFSv4: Fix a regression against the FreeBSD server SUNRPC: Fix another issue with rpc_client_register()
2013-07-20Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/josef/btrfs-next Pull btrfs fixes from Josef Bacik: "I'm playing the role of Chris Mason this week while he's on vacation. There are a few critical fixes for btrfs here, all regressions and have been tested well" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/josef/btrfs-next: Btrfs: fix wrong write offset when replacing a device Btrfs: re-add root to dead root list if we stop dropping it Btrfs: fix lock leak when resuming snapshot deletion Btrfs: update drop progress before stopping snapshot dropping
2013-07-20gpio/omap: fix build error when OF_GPIO is not defined.Javier Martinez Canillas
The OMAP GPIO driver check if the chip has an associated Device Tree node using the struct gpio_chip of_node member. But this is only build if CONFIG_OF_GPIO is defined which leads to the following error when using omap1_defconfig: linux/drivers/gpio/gpio-omap.c: In function 'omap_gpio_chip_init': linux/drivers/gpio/gpio-omap.c:1080:17: error: 'struct gpio_chip' has no member named 'of_node' linux/drivers/gpio/gpio-omap.c: In function 'omap_gpio_irq_map': linux/drivers/gpio/gpio-omap.c:1116:16: error: 'struct gpio_chip' has no member named 'of_node' Reported-by: Kevin Hilman <khilman@linaro.org> Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-07-20gpio/omap: auto request GPIO as input if used as IRQ via DTJavier Martinez Canillas
When an OMAP GPIO is used as an IRQ line, a call to gpio_request() has to be made to initialize the OMAP GPIO bank before a driver request the IRQ. Otherwise the call to request_irq() fails. Drives should not be aware of this neither care wether an IRQ line is a GPIO or not. They should just request the IRQ and this has to be handled by the irq_chip driver. With the current OMAP GPIO DT binding, if we define: gpio6: gpio@49058000 { compatible = "ti,omap3-gpio"; reg = <0x49058000 0x200>; interrupts = <34>; ti,hwmods = "gpio6"; gpio-controller; #gpio-cells = <2>; interrupt-controller; #interrupt-cells = <2>; }; interrupt-parent = <&gpio6>; interrupts = <16 8>; The GPIO is correctly mapped as an IRQ but a call to gpio_request() is never made. Since a call to the custom IRQ domain .map function handler is made for each GPIO used as an IRQ, the GPIO can be setup and configured as input there automatically. Changes since v3: - Use bank->chip.of_node instead of_have_populated_dt() to check DT or legacy boot as suggested by Jean-Christophe PLAGNIOL-VILLARD - Add a comment that this is just a temporary solution until and that it has to be removed once is handled by the IRQ core. Changes since v2: - Only make the call to gpio_request_one() conditional in the DT case as suggested by Grant Likely. Changes since v1: - Split the irq domain mapping function handler and the GPIO request in two different patches. Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk> Tested-by: Enric Balletbo i Serra <eballetbo@gmail.com> Acked-by: Grant Likely <grant.likely@secretlab.ca> Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com> Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-07-20gpio/omap: don't create an IRQ mapping for every GPIO on DTJavier Martinez Canillas
When a GPIO is defined as an interrupt line using Device Tree, a call to irq_create_of_mapping() is made that calls irq_create_mapping(). So, is not necessary to do the mapping for all OMAP GPIO lines and explicitly call irq_create_mapping() on the driver probe() when booting with Device Tree. Add a custom IRQ domain .map function handler that will be called by irq_create_mapping() to map the GPIO lines used as IRQ. This also allows to execute needed setup code such as configuring a GPIO as input and enabling the GPIO bank. Changes since v3: - Use bank->chip.of_node instead of_have_populated_dt() to check DT or legacy boot as suggested by Jean-Christophe PLAGNIOL-VILLARD Changes since v2: - Unconditionally do the IRQ setup in the .map() function and only call irq_create_mapping() in the gpio chip init to avoid code duplication as suggested by Grant Likely. Changes since v1: - Split the addition of the .map function handler and the automatic gpio request in two different patches. - Add GPIO IRQ setup logic to the irq domain mapping function. - Only call irq_create_mapping for every GPIO on legacy boot. - Only setup a GPIO IRQ on the .map function for DeviceTree boot. Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk> Tested-by: Enric Balletbo i Serra <eballetbo@gmail.com> Acked-by: Grant Likely <grant.likely@secretlab.ca> Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com> Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-07-20vfs: constify dentry parameter in d_count()Peng Tao
so that it can be used in places like d_compare/d_hash without causing a compiler warning. Signed-off-by: Peng Tao <tao.peng@emc.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-07-20livelock avoidance in sget()Al Viro
Eric Sandeen has found a nasty livelock in sget() - take a mount(2) about to fail. The superblock is on ->fs_supers, ->s_umount is held exclusive, ->s_active is 1. Along comes two more processes, trying to mount the same thing; sget() in each is picking that superblock, bumping ->s_count and trying to grab ->s_umount. ->s_active is 3 now. Original mount(2) finally gets to deactivate_locked_super() on failure; ->s_active is 2, superblock is still ->fs_supers because shutdown will *not* happen until ->s_active hits 0. ->s_umount is dropped and now we have two processes chasing each other: s_active = 2, A acquired ->s_umount, B blocked A sees that the damn thing is stillborn, does deactivate_locked_super() s_active = 1, A drops ->s_umount, B gets it A restarts the search and finds the same superblock. And bumps it ->s_active. s_active = 2, B holds ->s_umount, A blocked on trying to get it ... and we are in the earlier situation with A and B switched places. The root cause, of course, is that ->s_active should not grow until we'd got MS_BORN. Then failing ->mount() will have deactivate_locked_super() shut the damn thing down. Fortunately, it's easy to do - the key point is that grab_super() is called only for superblocks currently on ->fs_supers, so it can bump ->s_count and grab ->s_umount first, then check MS_BORN and bump ->s_active; we must never increment ->s_count for superblocks past ->kill_sb(), but grab_super() is never called for those. The bug is pretty old; we would've caught it by now, if not for accidental exclusion between sget() for block filesystems; the things like cgroup or e.g. mtd-based filesystems don't have anything of that sort, so they get bitten. The right way to deal with that is obviously to fix sget()... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-07-20allow O_TMPFILE to work with O_WRONLYAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>