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* hrtimer: Ignore hrtimer requeue when not in CB.Glenn Elliott2013-10-09
| | | | | | | | | | | | This patch removes a BUG_ON in the hrtimer root callback. Allows the hook to be called when not actually in the callback state. A BUG_ON forbid this state when a timer needed to be rearmed. Instead, we just ignore the rearm gracefully. This feature is needed for budget enforcement under bandwidth-inheritance.
* Protect LITMUS^RT tasks from re-nicingBjoern Brandenburg2013-08-07
| | | | | Assigning a nice value to LITMUS^RT tasks is meaningless. Bail out early.
* Don't call set_tsk_need_resched() on remote LITMUS^RT taskBjoern Brandenburg2013-08-07
| | | | | This patch fixes a BUG_ON() in litmus/preempt.c:33 reported by Felipe Cerqueira & Manohar Vanga.
* Hook into rt scheduling class to protect LITMUS^RT tasksBjoern Brandenburg2013-08-07
| | | | | | The rt scheduling class thinks it's the highest-priority scheduling class around. It is not in LITMUS^RT. Don't go preempting remote cores that run SCHED_LITMUS tasks.
* Don't trigger load balancer in scheduler tick for LITMUS^RTBjoern Brandenburg2013-08-07
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* Cache 'prev' in LITMUS^RT runqueueBjoern Brandenburg2013-08-07
| | | | | | LITMUS^RT plugins like to know who 'prev' is. pick_next_task() doesn't expose that info, so we just cache prev in the runqueue. Could robably be replaced by looking at 'current' instead.
* Hook into finish_switch()Bjoern Brandenburg2013-08-07
| | | | To keep track of stack usage and to notify plugin, if necessary.
* Reset SCHED_LITMUS scheduling class on forkBjoern Brandenburg2013-08-07
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* Block sched_setaffinity() for SCHED_LITMUS tasksBjoern Brandenburg2013-08-07
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* Integrate LITMUS^RT scheduling class with sched_setschedulerBjoern Brandenburg2013-08-07
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* Disable cut-to-CFS optimization in Linux schedulerBjoern Brandenburg2013-08-07
| | | | | Global plugins require that the plugin be called even if there currently is no real-time task executing on the local core.
* Integrate LITMUS^RT with try_to_wake_up() pathBjoern Brandenburg2013-08-07
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* Splice LITMUS^RT scheduling class into scheduler hierarchy above rt classBjoern Brandenburg2013-08-07
| | | | | Below stop_machine tasks, as such tasks never arise during normal operation.
* Call LITMUS^RT tick function from Linux tickBjoern Brandenburg2013-08-07
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* Add LITMUS^RT scheduling class in kernel/sched/MakefileBjoern Brandenburg2013-08-07
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* Introduce LITMUS^RT runqueue dummy into struct rqBjoern Brandenburg2013-08-07
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* Integrate SRP ceiling blocking callback with Linux schedulerBjoern Brandenburg2013-08-07
| | | | Check whether a suspension is required at end of schedule().
* Hookup sched_trace_XXX() tracing in Linux schedulerBjoern Brandenburg2013-08-07
| | | | This patch adds context switch tracing to the main Linux scheduler.
* Augment rt_task() with is_realtime()Bjoern Brandenburg2013-08-07
| | | | | | | | | | | Whenever the kernel checks for rt_task() to avoid delaying real-time tasks, we want it to also not delay LITMUS^RT tasks. Hence, most calls to rt_task() should be matched by an equivalent call to is_realtime(). Notably, this affects the implementations of select() and nanosleep(), which use timer_slack_ns when setting up timers for non-real-time tasks.
* Hook into fork(), exec(), and exit()Felipe Cerqueira2013-08-07
| | | | | Allow LITMUS^RT to do some work when a process is created or terminated.
* Call sched_state_task_picked() from pick_next_task_stop()Bjoern Brandenburg2013-08-07
| | | | | Otherwise, the scheduler state machine becomes confused (and goes into a rescheduling loop) when stop-machine is triggered.
* Integrate preemption state machine with Linux schedulerBjoern Brandenburg2013-08-07
| | | | Track when a processor is going to schedule "soon".
* Add LITMUS^RT core implementationBjoern Brandenburg2013-08-07
| | | | | | | | | | | | | This patch adds the core of LITMUS^RT: - library functionality (heaps, rt_domain, prioritization, etc.) - budget enforcement logic - job management - system call backends - virtual devices (control page, etc.) - scheduler plugin API (and dummy plugin) This code compiles, but is not yet integrated with the rest of Linux.
* Add hrtimer_start_on() supportFelipe Cerqueira2013-08-07
| | | | | | This patch adds hrtimer_start_on(), which allows arming timers on remote CPUs. This is needed to avoided timer interrupts on "shielded" CPUs and is also useful for implementing semi-partitioned schedulers.
* Add TRACE() debug tracing supportBjoern Brandenburg2013-08-07
| | | | This patch adds the infrastructure for the TRACE() debug macro.
* Add quantum aligment codeFelipe Cerqueira2013-08-07
| | | | Enable staggered ticks for PD^2.
* Add SCHED, SCHED2, TICK, and CXS overhead tracepointsBjoern Brandenburg2013-08-07
| | | | | | | This patch integrates the overhead tracepoints into the Linux scheduler that are compatible with plain vanilla Linux (i.e., not specific to LITMUS^RT plugins). This can be used to measure the overheads of an otherwise unmodified kernel.
* Integrate ft_irq_fired() with LinuxBjoern Brandenburg2013-08-07
| | | | | This patch hooks up Feather-Trace's ft_irq_fired() handler with Linux's interrupt handling infrastructure.
* tracing: Remove locking trace_types_lock from tracing_reset_all_online_cpus()Steven Rostedt (Red Hat)2013-08-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 09d8091c024ec88d1541d93eb8ddb2bd5cf10c39 upstream. Commit a82274151af "tracing: Protect ftrace_trace_arrays list in trace_events.c" added taking the trace_types_lock mutex in trace_events.c as there were several locations that needed it for protection. Unfortunately, it also encapsulated a call to tracing_reset_all_online_cpus() which also takes the trace_types_lock, causing a deadlock. This happens when a module has tracepoints and has been traced. When the module is removed, the trace events module notifier will grab the trace_types_lock, do a bunch of clean ups, and also clears the buffer by calling tracing_reset_all_online_cpus. This doesn't happen often which explains why it wasn't caught right away. Commit a82274151af was marked for stable, which means this must be sent to stable too. Link: http://lkml.kernel.org/r/51EEC646.7070306@broadcom.com Reported-by: Arend van Spril <arend@broadcom.com> Tested-by: Arend van Spriel <arend@broadcom.com> Cc: Alexander Z Lam <azl@google.com> Cc: Vaibhav Nagarnaik <vnagarnaik@google.com> Cc: David Sharp <dhsharp@google.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* tracing: Kill the unbalanced tr->ref++ in tracing_buffers_open()Oleg Nesterov2013-08-04
| | | | | | | | | | | | | | | | | | | | | | | | commit e70e78e3c83b536730e31231dd9b979768d8df3c upstream. tracing_buffers_open() does trace_array_get() and then it wrongly inrcements tr->ref again under trace_types_lock. This means that every caller leaks trace_array: # cd /sys/kernel/debug/tracing/ # mkdir instances/X # true < instances/X/per_cpu/cpu0/trace_pipe_raw # rmdir instances/X rmdir: failed to remove `instances/X': Device or resource busy Link: http://lkml.kernel.org/r/20130719153644.GA18899@redhat.com Signed-off-by: Oleg Nesterov <oleg@redhat.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* tracing: Miscellaneous fixes for trace_array ref countingAlexander Z Lam2013-08-04
| | | | | | | | | | | | | | | | | commit f77d09a384676bde6445413949d9d2c508ff3e62 upstream. Some error paths did not handle ref counting properly, and some trace files need ref counting. Link: http://lkml.kernel.org/r/1374171524-11948-1-git-send-email-azl@google.com Signed-off-by: Alexander Z Lam <azl@google.com> Cc: Vaibhav Nagarnaik <vnagarnaik@google.com> Cc: David Sharp <dhsharp@google.com> Cc: Alexander Z Lam <lambchop468@gmail.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* tracing: Fix error handling to ensure instances can always be removedAlexander Z Lam2013-08-04
| | | | | | | | | | | | | | | | | | | | commit 609e85a70bcd0eedf4ec60639dbcfb1ab011e054 upstream. Remove debugfs directories for tracing instances during creation if an error occurs causing the trace_array for that instance to not be added to ftrace_trace_arrays. If the directory continues to exist after the error, it cannot be removed because the respective trace_array is not in ftrace_trace_arrays. Link: http://lkml.kernel.org/r/1373502874-1706-2-git-send-email-azl@google.com Signed-off-by: Alexander Z Lam <azl@google.com> Cc: Vaibhav Nagarnaik <vnagarnaik@google.com> Cc: David Sharp <dhsharp@google.com> Cc: Alexander Z Lam <lambchop468@gmail.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* hrtimers: Move SMP function call to thread contextThomas Gleixner2013-07-28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 5ec2481b7b47a4005bb446d176e5d0257400c77d upstream. smp_call_function_* must not be called from softirq context. But clock_was_set() which calls on_each_cpu() is called from softirq context to implement a delayed clock_was_set() for the timer interrupt handler. Though that almost never gets invoked. A recent change in the resume code uses the softirq based delayed clock_was_set to support Xens resume mechanism. linux-next contains a new warning which warns if smp_call_function_* is called from softirq context which gets triggered by that Xen change. Fix this by moving the delayed clock_was_set() call to a work context. Reported-and-tested-by: Artem Savkov <artem.savkov@gmail.com> Reported-by: Sasha Levin <sasha.levin@oracle.com> Cc: David Vrabel <david.vrabel@citrix.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: H. Peter Anvin <hpa@zytor.com>, Cc: Konrad Wilk <konrad.wilk@oracle.com> Cc: John Stultz <john.stultz@linaro.org> Cc: xen-devel@lists.xen.org Cc: stable@vger.kernel.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* PM / Sleep: avoid 'autosleep' in shutdown progressLiu ShuoX2013-07-28
| | | | | | | | | | | | | | | | | | | | | | | | commit e5248a111bf4048a9f3fab1a9c94c4630a10592a upstream. Prevent automatic system suspend from happening during system shutdown by making try_to_suspend() check system_state and return immediately if it is not SYSTEM_RUNNING. This prevents the following breakage from happening (scenario from Zhang Yanmin): Kernel starts shutdown and calls all device driver's shutdown callback. When a driver's shutdown is called, the last wakelock is released and suspend-to-ram starts. However, as some driver's shut down callbacks already shut down devices and disabled runtime pm, the suspend-to-ram calls driver's suspend callback without noticing that device is already off and causes crash. [rjw: Changelog] Signed-off-by: Liu ShuoX <shuox.liu@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* tracing: Add trace_array_get/put() to event handlingSteven Rostedt (Red Hat)2013-07-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 8e2e2fa47129532a30cff6c25a47078dc97d9260 upstream. Commit a695cb58162 "tracing: Prevent deleting instances when they are being read" tried to fix a race between deleting a trace instance and reading contents of a trace file. But it wasn't good enough. The following could crash the kernel: # cd /sys/kernel/debug/tracing/instances # ( while :; do mkdir foo; rmdir foo; done ) & # ( while :; do echo 1 > foo/events/sched/sched_switch 2> /dev/null; done ) & Luckily this can only be done by root user, but it should be fixed regardless. The problem is that a delete of the file can happen after the write to the event is opened, but before the enabling happens. The solution is to make sure the trace_array is available before succeeding in opening for write, and incerment the ref counter while opened. Now the instance can be deleted when the events are writing to the buffer, but the deletion of the instance will disable all events before the instance is actually deleted. Reported-by: Alexander Lam <azl@google.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* tracing: Fix race between deleting buffer and setting eventsSteven Rostedt (Red Hat)2013-07-25
| | | | | | | | | | | | | | | | | commit 2a6c24afab70dbcfee49f4c76e1511eec1a3298b upstream. While analyzing the code, I discovered that there's a potential race between deleting a trace instance and setting events. There are a few races that can occur if events are being traced as the buffer is being deleted. Mostly the problem comes with freeing the descriptor used by the trace event callback. To prevent problems like this, the events are disabled before the buffer is deleted. The problem with the current solution is that the event_mutex is let go between disabling the events and freeing the files, which means that the events could be enabled again while the freeing takes place. Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* tracing: Get trace_array ref counts when accessing trace filesSteven Rostedt (Red Hat)2013-07-25
| | | | | | | | | | | | commit 7b85af63034818e43aee6c1d7bf1c7c6796a9073 upstream. When a trace file is opened that may access a trace array, it must increment its ref count to prevent it from being deleted. Reported-by: Alexander Lam <azl@google.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* tracing: Add trace_array_get/put() to handle instance refs betterSteven Rostedt (Red Hat)2013-07-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit ff451961a8b2a17667a7bfa39c86fb9b351445db upstream. Commit a695cb58162 "tracing: Prevent deleting instances when they are being read" tried to fix a race between deleting a trace instance and reading contents of a trace file. But it wasn't good enough. The following could crash the kernel: # cd /sys/kernel/debug/tracing/instances # ( while :; do mkdir foo; rmdir foo; done ) & # ( while :; do cat foo/trace &> /dev/null; done ) & Luckily this can only be done by root user, but it should be fixed regardless. The problem is that a delete of the file can happen after the reader starts to open the file but before it grabs the trace_types_mutex. The solution is to validate the trace array before using it. If the trace array does not exist in the list of trace arrays, then it returns -ENODEV. There's a possibility that a trace_array could be deleted and a new one created and the open would open its file instead. But that is very minor as it will just return the data of the new trace array, it may confuse the user but it will not crash the system. As this can only be done by root anyway, the race will only occur if root is deleting what its trying to read at the same time. Reported-by: Alexander Lam <azl@google.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* tracing: Protect ftrace_trace_arrays list in trace_events.cAlexander Z Lam2013-07-25
| | | | | | | | | | | | | | | | | commit a82274151af2b075163e3c42c828529dee311487 upstream. There are multiple places where the ftrace_trace_arrays list is accessed in trace_events.c without the trace_types_lock held. Link: http://lkml.kernel.org/r/1372732674-22726-1-git-send-email-azl@google.com Signed-off-by: Alexander Z Lam <azl@google.com> Cc: Vaibhav Nagarnaik <vnagarnaik@google.com> Cc: David Sharp <dhsharp@google.com> Cc: Alexander Z Lam <lambchop468@gmail.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* tracing: Make trace_marker use the correct per-instance bufferAlexander Z Lam2013-07-25
| | | | | | | | | | | | | | | | | | commit 2d71619c59fac95a5415a326162fa046161b938c upstream. The trace_marker file was present for each new instance created, but it added the trace mark to the global trace buffer instead of to the instance's buffer. Link: http://lkml.kernel.org/r/1372717885-4543-2-git-send-email-azl@google.com Signed-off-by: Alexander Z Lam <azl@google.com> Cc: David Sharp <dhsharp@google.com> Cc: Vaibhav Nagarnaik <vnagarnaik@google.com> Cc: Alexander Z Lam <lambchop468@gmail.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* tracing: Fix irqs-off tag display in syscall tracingzhangwei(Jovi)2013-07-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 11034ae9c20f4057a6127fc965906417978e69b2 upstream. All syscall tracing irqs-off tags are wrong, the syscall enter entry doesn't disable irqs. [root@jovi tracing]#echo "syscalls:sys_enter_open" > set_event [root@jovi tracing]# cat trace # tracer: nop # # entries-in-buffer/entries-written: 13/13 #P:2 # # _-----=> irqs-off # / _----=> need-resched # | / _---=> hardirq/softirq # || / _--=> preempt-depth # ||| / delay # TASK-PID CPU# |||| TIMESTAMP FUNCTION # | | | |||| | | irqbalance-513 [000] d... 56115.496766: sys_open(filename: 804e1a6, flags: 0, mode: 1b6) irqbalance-513 [000] d... 56115.497008: sys_open(filename: 804e1bb, flags: 0, mode: 1b6) sendmail-771 [000] d... 56115.827982: sys_open(filename: b770e6d1, flags: 0, mode: 1b6) The reason is syscall tracing doesn't record irq_flags into buffer. The proper display is: [root@jovi tracing]#echo "syscalls:sys_enter_open" > set_event [root@jovi tracing]# cat trace # tracer: nop # # entries-in-buffer/entries-written: 14/14 #P:2 # # _-----=> irqs-off # / _----=> need-resched # | / _---=> hardirq/softirq # || / _--=> preempt-depth # ||| / delay # TASK-PID CPU# |||| TIMESTAMP FUNCTION # | | | |||| | | irqbalance-514 [001] .... 46.213921: sys_open(filename: 804e1a6, flags: 0, mode: 1b6) irqbalance-514 [001] .... 46.214160: sys_open(filename: 804e1bb, flags: 0, mode: 1b6) <...>-920 [001] .... 47.307260: sys_open(filename: 4e82a0c5, flags: 80000, mode: 0) Link: http://lkml.kernel.org/r/1365564393-10972-3-git-send-email-jovi.zhangwei@huawei.com Signed-off-by: zhangwei(Jovi) <jovi.zhangwei@huawei.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* tracing: Failed to create system directorySteven Rostedt2013-07-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 6e94a780374ed31b280f939d4757e8d7858dff16 upstream. Running the following: # cd /sys/kernel/debug/tracing # echo p:i do_sys_open > kprobe_events # echo p:j schedule >> kprobe_events # cat kprobe_events p:kprobes/i do_sys_open p:kprobes/j schedule # echo p:i do_sys_open >> kprobe_events # cat kprobe_events p:kprobes/j schedule p:kprobes/i do_sys_open # ls /sys/kernel/debug/tracing/events/kprobes/ enable filter j Notice that the 'i' is missing from the kprobes directory. The console produces: "Failed to create system directory kprobes" This is because kprobes passes in a allocated name for the system and the ftrace event subsystem saves off that name instead of creating a duplicate for it. But the kprobes may free the system name making the pointer to it invalid. This bug was introduced by 92edca073c37 "tracing: Use direct field, type and system names" which switched from using kstrdup() on the system name in favor of just keeping apointer to it, as the internal ftrace event system names are static and exist for the life of the computer being booted. Instead of reverting back to duplicating system names again, we can use core_kernel_data() to determine if the passed in name was allocated or static. Then use the MSB of the ref_count to be a flag to keep track if the name was allocated or not. Then we can still save from having to duplicate strings that will always exist, but still copy the ones that may be freed. Reported-by: "zhangwei(Jovi)" <jovi.zhangwei@huawei.com> Reported-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* perf: Fix perf_lock_task_context() vs RCUPeter Zijlstra2013-07-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 058ebd0eba3aff16b144eabf4510ed9510e1416e upstream. Jiri managed to trigger this warning: [] ====================================================== [] [ INFO: possible circular locking dependency detected ] [] 3.10.0+ #228 Tainted: G W [] ------------------------------------------------------- [] p/6613 is trying to acquire lock: [] (rcu_node_0){..-...}, at: [<ffffffff810ca797>] rcu_read_unlock_special+0xa7/0x250 [] [] but task is already holding lock: [] (&ctx->lock){-.-...}, at: [<ffffffff810f2879>] perf_lock_task_context+0xd9/0x2c0 [] [] which lock already depends on the new lock. [] [] the existing dependency chain (in reverse order) is: [] [] -> #4 (&ctx->lock){-.-...}: [] -> #3 (&rq->lock){-.-.-.}: [] -> #2 (&p->pi_lock){-.-.-.}: [] -> #1 (&rnp->nocb_gp_wq[1]){......}: [] -> #0 (rcu_node_0){..-...}: Paul was quick to explain that due to preemptible RCU we cannot call rcu_read_unlock() while holding scheduler (or nested) locks when part of the read side critical section was preemptible. Therefore solve it by making the entire RCU read side non-preemptible. Also pull out the retry from under the non-preempt to play nice with RT. Reported-by: Jiri Olsa <jolsa@redhat.com> Helped-out-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* perf: Remove WARN_ON_ONCE() check in __perf_event_enable() for valid scenarioJiri Olsa2013-07-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 06f417968beac6e6b614e17b37d347aa6a6b1d30 upstream. The '!ctx->is_active' check has a valid scenario, so there's no need for the warning. The reason is that there's a time window between the 'ctx->is_active' check in the perf_event_enable() function and the __perf_event_enable() function having: - IRQs on - ctx->lock unlocked where the task could be killed and 'ctx' deactivated by perf_event_exit_task(), ending up with the warning below. So remove the WARN_ON_ONCE() check and add comments to explain it all. This addresses the following warning reported by Vince Weaver: [ 324.983534] ------------[ cut here ]------------ [ 324.984420] WARNING: at kernel/events/core.c:1953 __perf_event_enable+0x187/0x190() [ 324.984420] Modules linked in: [ 324.984420] CPU: 19 PID: 2715 Comm: nmi_bug_snb Not tainted 3.10.0+ #246 [ 324.984420] Hardware name: Supermicro X8DTN/X8DTN, BIOS 4.6.3 01/08/2010 [ 324.984420] 0000000000000009 ffff88043fce3ec8 ffffffff8160ea0b ffff88043fce3f00 [ 324.984420] ffffffff81080ff0 ffff8802314fdc00 ffff880231a8f800 ffff88043fcf7860 [ 324.984420] 0000000000000286 ffff880231a8f800 ffff88043fce3f10 ffffffff8108103a [ 324.984420] Call Trace: [ 324.984420] <IRQ> [<ffffffff8160ea0b>] dump_stack+0x19/0x1b [ 324.984420] [<ffffffff81080ff0>] warn_slowpath_common+0x70/0xa0 [ 324.984420] [<ffffffff8108103a>] warn_slowpath_null+0x1a/0x20 [ 324.984420] [<ffffffff81134437>] __perf_event_enable+0x187/0x190 [ 324.984420] [<ffffffff81130030>] remote_function+0x40/0x50 [ 324.984420] [<ffffffff810e51de>] generic_smp_call_function_single_interrupt+0xbe/0x130 [ 324.984420] [<ffffffff81066a47>] smp_call_function_single_interrupt+0x27/0x40 [ 324.984420] [<ffffffff8161fd2f>] call_function_single_interrupt+0x6f/0x80 [ 324.984420] <EOI> [<ffffffff816161a1>] ? _raw_spin_unlock_irqrestore+0x41/0x70 [ 324.984420] [<ffffffff8113799d>] perf_event_exit_task+0x14d/0x210 [ 324.984420] [<ffffffff810acd04>] ? switch_task_namespaces+0x24/0x60 [ 324.984420] [<ffffffff81086946>] do_exit+0x2b6/0xa40 [ 324.984420] [<ffffffff8161615c>] ? _raw_spin_unlock_irq+0x2c/0x30 [ 324.984420] [<ffffffff81087279>] do_group_exit+0x49/0xc0 [ 324.984420] [<ffffffff81096854>] get_signal_to_deliver+0x254/0x620 [ 324.984420] [<ffffffff81043057>] do_signal+0x57/0x5a0 [ 324.984420] [<ffffffff8161a164>] ? __do_page_fault+0x2a4/0x4e0 [ 324.984420] [<ffffffff8161665c>] ? retint_restore_args+0xe/0xe [ 324.984420] [<ffffffff816166cd>] ? retint_signal+0x11/0x84 [ 324.984420] [<ffffffff81043605>] do_notify_resume+0x65/0x80 [ 324.984420] [<ffffffff81616702>] retint_signal+0x46/0x84 [ 324.984420] ---[ end trace 442ec2f04db3771a ]--- Reported-by: Vince Weaver <vincent.weaver@maine.edu> Signed-off-by: Jiri Olsa <jolsa@redhat.com> Suggested-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1373384651-6109-2-git-send-email-jolsa@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* perf: Clone child context from parent context pmuJiri Olsa2013-07-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 734df5ab549ca44f40de0f07af1c8803856dfb18 upstream. Currently when the child context for inherited events is created, it's based on the pmu object of the first event of the parent context. This is wrong for the following scenario: - HW context having HW and SW event - HW event got removed (closed) - SW event stays in HW context as the only event and its pmu is used to clone the child context The issue starts when the cpu context object is touched based on the pmu context object (__get_cpu_context). In this case the HW context will work with SW cpu context ending up with following WARN below. Fixing this by using parent context pmu object to clone from child context. Addresses the following warning reported by Vince Weaver: [ 2716.472065] ------------[ cut here ]------------ [ 2716.476035] WARNING: at kernel/events/core.c:2122 task_ctx_sched_out+0x3c/0x) [ 2716.476035] Modules linked in: nfsd auth_rpcgss oid_registry nfs_acl nfs locn [ 2716.476035] CPU: 0 PID: 3164 Comm: perf_fuzzer Not tainted 3.10.0-rc4 #2 [ 2716.476035] Hardware name: AOpen DE7000/nMCP7ALPx-DE R1.06 Oct.19.2012, BI2 [ 2716.476035] 0000000000000000 ffffffff8102e215 0000000000000000 ffff88011fc18 [ 2716.476035] ffff8801175557f0 0000000000000000 ffff880119fda88c ffffffff810ad [ 2716.476035] ffff880119fda880 ffffffff810af02a 0000000000000009 ffff880117550 [ 2716.476035] Call Trace: [ 2716.476035] [<ffffffff8102e215>] ? warn_slowpath_common+0x5b/0x70 [ 2716.476035] [<ffffffff810ab2bd>] ? task_ctx_sched_out+0x3c/0x5f [ 2716.476035] [<ffffffff810af02a>] ? perf_event_exit_task+0xbf/0x194 [ 2716.476035] [<ffffffff81032a37>] ? do_exit+0x3e7/0x90c [ 2716.476035] [<ffffffff810cd5ab>] ? __do_fault+0x359/0x394 [ 2716.476035] [<ffffffff81032fe6>] ? do_group_exit+0x66/0x98 [ 2716.476035] [<ffffffff8103dbcd>] ? get_signal_to_deliver+0x479/0x4ad [ 2716.476035] [<ffffffff810ac05c>] ? __perf_event_task_sched_out+0x230/0x2d1 [ 2716.476035] [<ffffffff8100205d>] ? do_signal+0x3c/0x432 [ 2716.476035] [<ffffffff810abbf9>] ? ctx_sched_in+0x43/0x141 [ 2716.476035] [<ffffffff810ac2ca>] ? perf_event_context_sched_in+0x7a/0x90 [ 2716.476035] [<ffffffff810ac311>] ? __perf_event_task_sched_in+0x31/0x118 [ 2716.476035] [<ffffffff81050dd9>] ? mmdrop+0xd/0x1c [ 2716.476035] [<ffffffff81051a39>] ? finish_task_switch+0x7d/0xa6 [ 2716.476035] [<ffffffff81002473>] ? do_notify_resume+0x20/0x5d [ 2716.476035] [<ffffffff813654f5>] ? retint_signal+0x3d/0x78 [ 2716.476035] ---[ end trace 827178d8a5966c3d ]--- Reported-by: Vince Weaver <vincent.weaver@maine.edu> Signed-off-by: Jiri Olsa <jolsa@redhat.com> Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1373384651-6109-1-git-send-email-jolsa@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* uprobes: Fix return value in error handling pathzhangwei(Jovi)2013-07-25
| | | | | | | | | | | | | | | | | | | | | | | | commit fa44063f9ef163c3a4c8d8c0465bb8a056b42035 upstream. When wrong argument is passed into uprobe_events it does not return an error: [root@jovi tracing]# echo 'p:myprobe /bin/bash' > uprobe_events [root@jovi tracing]# The proper response is: [root@jovi tracing]# echo 'p:myprobe /bin/bash' > uprobe_events -bash: echo: write error: Invalid argument Link: http://lkml.kernel.org/r/51B964FF.5000106@huawei.com Signed-off-by: zhangwei(Jovi) <jovi.zhangwei@huawei.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: <srikar@linux.vnet.ibm.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* printk: Fix rq->lock vs logbuf_lock unlock lock inversionBu, Yitian2013-07-25
| | | | | | | | | | | | | | | | | | | commit dbda92d16f8655044e082930e4e9d244b87fde77 upstream. commit 07354eb1a74d1 ("locking printk: Annotate logbuf_lock as raw") reintroduced a lock inversion problem which was fixed in commit 0b5e1c5255 ("printk: Release console_sem after logbuf_lock"). This happened probably when fixing up patch rejects. Restore the ordering and unlock logbuf_lock before releasing console_sem. Signed-off-by: ybu <ybu@qti.qualcomm.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/E807E903FE6CBE4D95E420FBFCC273B827413C@nasanexd01h.na.qualcomm.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* tick: Prevent uncontrolled switch to oneshot modeThomas Gleixner2013-07-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 1f73a9806bdd07a5106409bbcab3884078bd34fe upstream. When the system switches from periodic to oneshot mode, the broadcast logic causes a possibility that a CPU which has not yet switched to oneshot mode puts its own clock event device into oneshot mode without updating the state and the timer handler. CPU0 CPU1 per cpu tickdev is in periodic mode and switched to broadcast Switch to oneshot mode tick_broadcast_switch_to_oneshot() cpumask_copy(tick_oneshot_broacast_mask, tick_broadcast_mask); broadcast device mode = oneshot Timer interrupt irq_enter() tick_check_oneshot_broadcast() dev->set_mode(ONESHOT); tick_handle_periodic() if (dev->mode == ONESHOT) dev->next_event += period; FAIL. We fail, because dev->next_event contains KTIME_MAX, if the device was in periodic mode before the uncontrolled switch to oneshot happened. We must copy the broadcast bits over to the oneshot mask, because otherwise a CPU which relies on the broadcast would not been woken up anymore after the broadcast device switched to oneshot mode. So we need to verify in tick_check_oneshot_broadcast() whether the CPU has already switched to oneshot mode. If not, leave the device untouched and let the CPU switch controlled into oneshot mode. This is a long standing bug, which was never noticed, because the main user of the broadcast x86 cannot run into that scenario, AFAICT. The nonarchitected timer mess of ARM creates a gazillion of differently broken abominations which trigger the shortcomings of that broadcast code, which better had never been necessary in the first place. Reported-and-tested-by: Stehle Vincent-B46079 <B46079@freescale.com> Reviewed-by: Stephen Boyd <sboyd@codeaurora.org> Cc: John Stultz <john.stultz@linaro.org>, Cc: Mark Rutland <mark.rutland@arm.com> Link: http://lkml.kernel.org/r/alpine.DEB.2.02.1307012153060.4013@ionos.tec.linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* tick: Sanitize broadcast control logicThomas Gleixner2013-07-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 07bd1172902e782f288e4d44b1fde7dec0f08b6f upstream. The recent implementation of a generic dummy timer resulted in a different registration order of per cpu local timers which made the broadcast control logic go belly up. If the dummy timer is the first clock event device which is registered for a CPU, then it is installed, the broadcast timer is initialized and the CPU is marked as broadcast target. If a real clock event device is installed after that, we can fail to take the CPU out of the broadcast mask. In the worst case we end up with two periodic timer events firing for the same CPU. One from the per cpu hardware device and one from the broadcast. Now the problem is that we have no way to distinguish whether the system is in a state which makes broadcasting necessary or the broadcast bit was set due to the nonfunctional dummy timer installment. To solve this we need to keep track of the system state seperately and provide a more detailed decision logic whether we keep the CPU in broadcast mode or not. The old decision logic only clears the broadcast mode, if the newly installed clock event device is not affected by power states. The new logic clears the broadcast mode if one of the following is true: - The new device is not affected by power states. - The system is not in a power state affected mode - The system has switched to oneshot mode. The oneshot broadcast is controlled from the deep idle state. The CPU is not in idle at this point, so it's safe to remove it from the mask. If we clear the broadcast bit for the CPU when a new device is installed, we also shutdown the broadcast device when this was the last CPU in the broadcast mask. If the broadcast bit is kept, then we leave the new device in shutdown state and rely on the broadcast to deliver the timer interrupts via the broadcast ipis. Reported-and-tested-by: Stehle Vincent-B46079 <B46079@freescale.com> Reviewed-by: Stephen Boyd <sboyd@codeaurora.org> Cc: John Stultz <john.stultz@linaro.org>, Cc: Mark Rutland <mark.rutland@arm.com> Link: http://lkml.kernel.org/r/alpine.DEB.2.02.1307012153060.4013@ionos.tec.linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* timer: Fix jiffies wrap behavior of round_jiffies_common()Bart Van Assche2013-07-21
| | | | | | | | | | | | | | | commit 9e04d3804d3ac97d8c03a41d78d0f0674b5d01e1 upstream. Direct compare of jiffies related values does not work in the wrap around case. Replace it with time_is_after_jiffies(). Signed-off-by: Bart Van Assche <bvanassche@acm.org> Cc: Arjan van de Ven <arjan@infradead.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Link: http://lkml.kernel.org/r/519BC066.5080600@acm.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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