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2015-10-26timeconst: Update path in commentJason A. Donenfeld
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Cc: hofrat@osadl.org Link: http://lkml.kernel.org/r/1436894685-5868-1-git-send-email-Jason@zx2c4.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-10-23Merge branch 'sched-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler fixes from Ingo Molnar: "Misc fixes all around the map: an instrumentation fix, a nohz usability fix, a lockdep annotation fix and two task group scheduling fixes" * 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched/core: Add missing lockdep_unpin() annotations sched/deadline: Fix migration of SCHED_DEADLINE tasks nohz: Revert "nohz: Set isolcpus when nohz_full is set" sched/fair: Update task group's load_avg after task migration sched/fair: Fix overly small weight for interactive group entities sched, tracing: Stop/start critical timings around the idle=poll idle loop
2015-10-23Merge branch 'akpm' (patches from Andrew)Linus Torvalds
Merge fixes from Andrew Morton: "9 fixes" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: ocfs2/dlm: unlock lockres spinlock before dlm_lockres_put fault-inject: fix inverted interval/probability values in printk lib/Kconfig.debug: disable -Wframe-larger-than warnings with KASAN=y mm: make sendfile(2) killable thp: use is_zero_pfn() only after pte_present() check mailmap: update Javier Martinez Canillas' email MAINTAINERS: add Sergey as zsmalloc reviewer mm: cma: fix incorrect type conversion for size during dma allocation kmod: don't run async usermode helper as a child of kworker thread
2015-10-23sched/core: Add missing lockdep_unpin() annotationsPeter Zijlstra
Luca and Wanpeng reported two missing annotations that led to false lockdep complaints. Add the missing annotations. Reported-by: Luca Abeni <luca.abeni@unitn.it> Reported-by: Wanpeng Li <wanpeng.li@hotmail.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Juri Lelli <juri.lelli@arm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Fixes: cbce1a686700 ("sched,lockdep: Employ lock pinning") Link: http://lkml.kernel.org/r/20151023095008.GY17308@twins.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-10-23kmod: don't run async usermode helper as a child of kworker threadOleg Nesterov
call_usermodehelper_exec_sync() does fork() + wait() with "unignored" SIGCHLD. What we have missed is that this worker thread can have other children previously forked by call_usermodehelper_exec_work() without UMH_WAIT_PROC. If such a child exits in between it becomes a zombie because auto-reaping only works if SIGCHLD is ignored, and nobody can reap it (unless/until this worker thread exits too). Change the !UMH_WAIT_PROC case to use CLONE_PARENT. Note: this is only first step. All PF_KTHREAD tasks, even created by kernel_thread() should have ->parent == kthreadd by default. Fixes: bb304a5c6fc63d8506c ("kmod: handle UMH_WAIT_PROC from system unbound workqueue") Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Rik van Riel <riel@redhat.com> Cc: Christoph Lameter <cl@linux.com> Cc: Tejun Heo <tj@kernel.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-10-22Merge branch 'irq/for-arm' of ↵Catalin Marinas
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip This is an incremental fix for a patch previously pulled from tip irq/for-arm. * 'irq/for-arm' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: genirq: Make the cpuhotplug migration code less noisy
2015-10-22pstore: add pstore unregisterGeliang Tang
pstore doesn't support unregistering yet. It was marked as TODO. This patch adds some code to fix it: 1) Add functions to unregister kmsg/console/ftrace/pmsg. 2) Add a function to free compression buffer. 3) Unmap the memory and free it. 4) Add a function to unregister pstore filesystem. Signed-off-by: Geliang Tang <geliangtang@163.com> Acked-by: Kees Cook <keescook@chromium.org> [Removed __exit annotation from ramoops_remove(). Reported by Arnd Bergmann] Signed-off-by: Tony Luck <tony.luck@intel.com>
2015-10-22bpf: introduce bpf_perf_event_output() helperAlexei Starovoitov
This helper is used to send raw data from eBPF program into special PERF_TYPE_SOFTWARE/PERF_COUNT_SW_BPF_OUTPUT perf_event. User space needs to perf_event_open() it (either for one or all cpus) and store FD into perf_event_array (similar to bpf_perf_event_read() helper) before eBPF program can send data into it. Today the programs triggered by kprobe collect the data and either store it into the maps or print it via bpf_trace_printk() where latter is the debug facility and not suitable to stream the data. This new helper replaces such bpf_trace_printk() usage and allows programs to have dedicated channel into user space for post-processing of the raw data collected. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-22perf: pad raw data samples automaticallyAlexei Starovoitov
Instead of WARN_ON in perf_event_output() on unpaded raw samples, pad them automatically. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-22genirq: Make the cpuhotplug migration code less noisyThomas Gleixner
The original arm code has a pr_debug() statement for the case where the irq chip has no set_affinity() callback. That's sufficient for debugging and we really don't want to spam dmesg with useless warnings for the normal case. Fixes: f1e0bb0ad473: "genirq: Introduce generic irq migration for cpu hotunplug" Reported-by: Geert Uytterhoeven <geert@linux-m68k.org> Requested-by: Russell King <linux@arm.linux.org.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Yang Yingliang <yangyingliang@huawei.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Hanjun Guo <hanjun.guo@linaro.org> Cc: Jiang Liu <jiang.liu@linux.intel.com>
2015-10-21KEYS: Merge the type-specific data with the payload dataDavid Howells
Merge the type-specific data with the payload data into one four-word chunk as it seems pointless to keep them separate. Use user_key_payload() for accessing the payloads of overloaded user-defined keys. Signed-off-by: David Howells <dhowells@redhat.com> cc: linux-cifs@vger.kernel.org cc: ecryptfs@vger.kernel.org cc: linux-ext4@vger.kernel.org cc: linux-f2fs-devel@lists.sourceforge.net cc: linux-nfs@vger.kernel.org cc: ceph-devel@vger.kernel.org cc: linux-ima-devel@lists.sourceforge.net
2015-10-21certs: add .gitignore to stop git nagging about x509_certificate_listPaul Gortmaker
Currently we see this in "git status" if we build in the source dir: Untracked files: (use "git add <file>..." to include in what will be committed) certs/x509_certificate_list It looks like it used to live in kernel/ so we squash that .gitignore entry at the same time. I didn't bother to dig through git history to see when it moved, since it is just a minor annoyance at most. Cc: David Woodhouse <dwmw2@infradead.org> Cc: keyrings@linux-nfs.org Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: David Howells <dhowells@redhat.com>
2015-10-21tracing: Remove {start,stop}_branch_traceDmitry Safonov
Both start_branch_trace() and stop_branch_trace() are used in only one location, and are both static. As they are small functions there is no need to keep them separated out. Link: http://lkml.kernel.org/r/1445000689-32596-1-git-send-email-0x7f454c46@gmail.com Signed-off-by: Dmitry Safonov <0x7f454c46@gmail.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2015-10-21kexec/crash: Say which char is the unrecognizedBorislav Petkov
It is helpful when the crashkernel cmdline parsing routines actually say which character is the unrecognized one. Make them do so. Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Dave Young <dyoung@redhat.com> Reviewed-by: Joerg Roedel <jroedel@suse.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Baoquan He <bhe@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Juergen Gross <jgross@suse.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mark Salter <msalter@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: WANG Chao <chaowang@redhat.com> Cc: jerry_hoemann@hp.com Link: http://lkml.kernel.org/r/1445246268-26285-8-git-send-email-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-10-20tracing: gpio: Add Kconfig option for enabling/disabling trace eventsTal Shorer
Add a new options to trace Kconfig, CONFIG_TRACING_EVENTS_GPIO, that is used for enabling/disabling compilation of gpio function trace events. Link: http://lkml.kernel.org/r/1438432079-11704-4-git-send-email-tal.shorer@gmail.com Acked-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Tal Shorer <tal.shorer@gmail.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2015-10-20tracing: Do not allow stack_tracer to record stack in NMISteven Rostedt (Red Hat)
The code in stack tracer should not be executed within an NMI as it grabs spinlocks and stack tracing an NMI gives the possibility of causing a deadlock. Although this is safe on x86_64, because it does not perform stack traces when the task struct stack is not in use (interrupts and NMIs), it may be an issue for NMIs on i386 and other archs that use the same stack as the NMI. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2015-10-20ftrace: add module globbingDmitry Safonov
Extend module command for function filter selection with globbing. It uses the same globbing as function filter. sh# echo '*alloc*:mod:*' > set_ftrace_filter Will trace any function with the letters 'alloc' in the name in any module but not in kernel. sh# echo '!*alloc*:mod:ipv6' >> set_ftrace_filter Will prevent from tracing functions with 'alloc' in the name from module ipv6 (do not forget to append to set_ftrace_filter file). sh# echo '*alloc*:mod:!ipv6' > set_ftrace_filter Will trace functions with 'alloc' in the name from kernel and any module except ipv6. sh# echo '*alloc*:mod:!*' > set_ftrace_filter Will trace any function with the letters 'alloc' in the name only from kernel, but not from any module. sh# echo '*:mod:!*' > set_ftrace_filter or sh# echo ':mod:!' > set_ftrace_filter Will trace every function in the kernel, but will not trace functions from any module. sh# echo '*:mod:*' > set_ftrace_filter or sh# echo ':mod:' > set_ftrace_filter As the opposite will trace all functions from all modules, but not from kernel. sh# echo '*:mod:*snd*' > set_ftrace_filter Will trace your sound drivers only (if any). Link: http://lkml.kernel.org/r/1443545176-3215-4-git-send-email-0x7f454c46@gmail.com Signed-off-by: Dmitry Safonov <0x7f454c46@gmail.com> [ Made format changes ] Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2015-10-20ftrace: Introduce ftrace_glob structureDmitry Safonov
ftrace_match parameters are very related and I reduce the number of local variables & parameters with it. This is also preparation for module globbing as it would introduce more realated variables & parameters. Link: http://lkml.kernel.org/r/1443545176-3215-3-git-send-email-0x7f454c46@gmail.com Signed-off-by: Dmitry Safonov <0x7f454c46@gmail.com> [ Made some formatting changes ] Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2015-10-20tracing: Have stack tracer force RCU to be watchingSteven Rostedt (Red Hat)
The stack tracer was triggering the WARN_ON() in module.c: static void module_assert_mutex_or_preempt(void) { #ifdef CONFIG_LOCKDEP if (unlikely(!debug_locks)) return; WARN_ON(!rcu_read_lock_sched_held() && !lockdep_is_held(&module_mutex)); #endif } The reason is that the stack tracer traces all function calls, and some of those calls happen while exiting or entering user space and idle. Some of these functions are called after RCU had already stopped watching, as RCU does not watch userspace or idle CPUs. If a max stack is hit, then the save_stack_trace() is called, which will check module addresses and call module_assert_mutex_or_preempt(), and then trigger the warning. Sad part is, the warning itself will also do a stack trace and tigger the same warning. That probably should be fixed. The warning was added by 0be964be0d45 "module: Sanitize RCU usage and locking" but this bug has probably been around longer. But it's unlikely to cause much harm, but the new warning causes the system to lock up. Cc: stable@vger.kernel.org # 4.2+ Cc: Peter Zijlstra <peterz@infradead.org> Cc:"Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2015-10-20Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Conflicts: drivers/net/usb/asix_common.c net/ipv4/inet_connection_sock.c net/switchdev/switchdev.c In the inet_connection_sock.c case the request socket hashing scheme is completely different in net-next. The other two conflicts were overlapping changes. Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-20Merge branch 'fortglx/4.4/time' of ↵Thomas Gleixner
https://git.linaro.org/people/john.stultz/linux into timers/core Time updates from John Stultz: - More 2038 work from Arnd Bergmann around ntp and pps
2015-10-20sched: Don't scan all-offline ->cpus_allowed twice if !CONFIG_CPUSETSOleg Nesterov
If CONFIG_CPUSETS=n then "case cpuset" changes the state and runs the already failed for_each_cpu() loop again for no reason. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Tejun Heo <tj@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: heiko.carstens@de.ibm.com Link: http://lkml.kernel.org/r/20151010185315.GA24100@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-10-20sched: Move cpu_active() tests from stop_two_cpus() into migrate_swap_stop()Peter Zijlstra
The cpu_active() tests are not fundamentally part of stop_two_cpus(), move then into the scheduler where they belong. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-10-20sched: Start stopper earlyPeter Zijlstra
Ensure the stopper thread is active 'early', because the load balancer pretty much assumes that its available. And when 'online && active' the load-balancer is fully available. Not only the numa balancing stop_two_cpus() caller relies on it, but also the self migration stuff does, and at CPU_ONLINE time the cpu really is 'free' to run anything. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Tejun Heo <tj@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: heiko.carstens@de.ibm.com Link: http://lkml.kernel.org/r/20151009160054.GA10176@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-10-20stop_machine: Kill cpu_stop_threads->setup() and cpu_stop_unpark()Oleg Nesterov
Now that we always use stop_machine_unpark() to wake the stopper threas up, we can kill ->setup() and fold cpu_stop_unpark() into stop_machine_unpark(). And we do not need stopper->lock to set stopper->enabled = true. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Tejun Heo <tj@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: heiko.carstens@de.ibm.com Link: http://lkml.kernel.org/r/20151009160051.GA10169@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-10-20stop_machine: Kill smp_hotplug_thread->pre_unpark, introduce ↵Oleg Nesterov
stop_machine_unpark() 1. Change smpboot_unpark_thread() to check ->selfparking, just like smpboot_park_thread() does. 2. Introduce stop_machine_unpark() which sets ->enabled and calls kthread_unpark(). 3. Change smpboot_thread_call() and cpu_stop_init() to call stop_machine_unpark() by hand. This way: - IMO the ->selfparking logic becomes more consistent. - We can kill the smp_hotplug_thread->pre_unpark() method. - We can easily unpark the stopper thread earlier. Say, we can move stop_machine_unpark() from smpboot_thread_call() to sched_cpu_active() as Peter suggests. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Tejun Heo <tj@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: heiko.carstens@de.ibm.com Link: http://lkml.kernel.org/r/20151009160049.GA10166@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-10-20stop_machine: Change cpu_stop_queue_two_works() to rely on stopper->enabledOleg Nesterov
Change cpu_stop_queue_two_works() to ensure that both CPU's have stopper->enabled == T or fail otherwise. This way stop_two_cpus() no longer needs to check cpu_active() to avoid the deadlock. This patch doesn't remove these checks, we will do this later. Note: we need to take both stopper->lock's at the same time, but this will also help to remove lglock from stop_machine.c, so I hope this is fine. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Tejun Heo <tj@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: heiko.carstens@de.ibm.com Link: http://lkml.kernel.org/r/20151008170141.GA25537@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-10-20stop_machine: Introduce __cpu_stop_queue_work() and cpu_stop_queue_two_works()Oleg Nesterov
Preparation to simplify the review of the next change. Add two simple helpers, __cpu_stop_queue_work() and cpu_stop_queue_two_works() which simply take a bit of code from their callers. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Tejun Heo <tj@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: heiko.carstens@de.ibm.com Link: http://lkml.kernel.org/r/20151008145134.GA18146@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-10-20stop_machine: Ensure that a queued callback will be called before ↵Oleg Nesterov
cpu_stop_park() cpu_stop_queue_work() checks stopper->enabled before it queues the work, but ->enabled == T can only guarantee cpu_stop_signal_done() if we race with cpu_down(). This is not enough for stop_two_cpus() or stop_machine(), they will deadlock if multi_cpu_stop() won't be called by one of the target CPU's. stop_machine/stop_cpus are fine, they rely on stop_cpus_mutex. But stop_two_cpus() has to check cpu_active() to avoid the same race with hotplug, and this check is very unobvious and probably not even correct if we race with cpu_up(). Change cpu_down() pass to clear ->enabled before cpu_stopper_thread() flushes the pending ->works and returns with KTHREAD_SHOULD_PARK set. Note also that smpboot_thread_call() calls cpu_stop_unpark() which sets enabled == T at CPU_ONLINE stage, so this CPU can't go away until cpu_stopper_thread() is called at least once. This all means that if cpu_stop_queue_work() succeeds, we know that work->fn() will be called. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Tejun Heo <tj@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: heiko.carstens@de.ibm.com Link: http://lkml.kernel.org/r/20151008145131.GA18139@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-10-20Merge branch 'sched/urgent' into sched/core, to pick up fixes and resolve ↵Ingo Molnar
conflicts Conflicts: kernel/sched/fair.c Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-10-20Merge tag 'v4.3-rc6' into locking/core, to pick up fixes before applying new ↵Ingo Molnar
changes Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-10-20sched/deadline: Fix migration of SCHED_DEADLINE tasksLuca Abeni
Commit: 9d5142624256 ("sched/deadline: Reduce rq lock contention by eliminating locking of non-feasible target") broke select_task_rq_dl() and find_lock_later_rq(), because it introduced a comparison between the local task's deadline and dl.earliest_dl.curr of the remote queue. However, if the remote runqueue does not contain any SCHED_DEADLINE task its earliest_dl.curr is 0 (always smaller than the deadline of the local task) and the remote runqueue is not selected for pushing. As a result, if an application creates multiple SCHED_DEADLINE threads, they will never be pushed to runqueues that do not already contain SCHED_DEADLINE tasks. This patch fixes the issue by checking if dl.dl_nr_running == 0. Signed-off-by: Luca Abeni <luca.abeni@unitn.it> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Juri Lelli <juri.lelli@arm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Wanpeng Li <wanpeng.li@linux.intel.com> Fixes: 9d5142624256 ("sched/deadline: Reduce rq lock contention by eliminating locking of non-feasible target") Link: http://lkml.kernel.org/r/1444982781-15608-1-git-send-email-luca.abeni@unitn.it Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-10-20nohz: Revert "nohz: Set isolcpus when nohz_full is set"Frederic Weisbecker
This reverts: 8cb9764fc88b ("nohz: Set isolcpus when nohz_full is set") We assumed that full-nohz users always want scheduler isolation on full dynticks CPUs, therefore we included full-nohz CPUs on cpu_isolated_map. This means that tasks run by default on CPUs outside the nohz_full range unless their affinity is explicity overwritten. This suits pure isolation workloads but when the machine is needed to run common workloads, the available sets of CPUs to run common tasks becomes reduced. We reach an extreme case when CONFIG_NO_HZ_FULL_ALL is enabled as it leaves only CPU 0 for non-isolation tasks, which makes people think that their supercomputer regressed to 90's UP - which is true in a sense. Some full-nohz users appear to be interested in running normal workloads either before or after an isolation workload. Full-nohz isn't optimized toward normal workloads but it's still better than UP performance. We are reaching a limitation in kernel presets here. Lets revert this cpu_isolated_map inclusion and let userspace do its own scheduler isolation using cpusets or explicit affinity settings. Reported-by: Ingo Molnar <mingo@kernel.org> Reported-by: Mike Galbraith <umgwanakikbuti@gmail.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Chris Metcalf <cmetcalf@ezchip.com> Cc: Christoph Lameter <cl@linux.com> Cc: Dave Jones <davej@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Paul E . McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Link: http://lkml.kernel.org/r/1444663283-30068-1-git-send-email-fweisbec@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-10-20sched/fair: Update task group's load_avg after task migrationYuyang Du
When cfs_rq has cfs_rq->removed_load_avg set (when a task migrates from this cfs_rq), we need to update its contribution to the group's load_avg. This should not increase tg's update too much, because in most cases, the cfs_rq has already decayed its load_avg. Tested-by: Dietmar Eggemann <dietmar.eggemann@arm.com> Signed-off-by: Yuyang Du <yuyang.du@intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Dietmar Eggemann <dietmar.eggemann@arm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1444699103-20272-2-git-send-email-yuyang.du@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-10-20sched/fair: Fix overly small weight for interactive group entitiesYuyang Du
Commit: 9d89c257dfb9 ("sched/fair: Rewrite runnable load and utilization average tracking") led to an overly small weight for interactive group entities. The bad case can be easily reproduced when a number of CPU hogs compete for the CPUs at the same time (thanks to Mike). This is largly because the task group's load average tracking cross CPUs lags behind the real changes. To fix this we accelerate the group share distribution process by using the load.weight of the cfs_rq. This may increase the entire group's share, but we have to do so to protect the (fragile) interactive tasks, especially from CPU hogs. Reported-by: Mike Galbraith <umgwanakikbuti@gmail.com> Tested-by: Dietmar Eggemann <dietmar.eggemann@arm.com> Tested-by: Mike Galbraith <umgwanakikbuti@gmail.com> Signed-off-by: Yuyang Du <yuyang.du@intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Dietmar Eggemann <dietmar.eggemann@arm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1444699103-20272-1-git-send-email-yuyang.du@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-10-19Merge branch 'for-mingo' of ↵Ingo Molnar
git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu Pull RCU updates from Paul E. McKenney: - Miscellaneous fixes. (Paul E. McKenney, Boqun Feng, Oleg Nesterov, Patrick Marlier) - Improvements to expedited grace periods. (Paul E. McKenney) - Performance improvements to and locktorture tests for percpu-rwsem. (Oleg Nesterov, Paul E. McKenney) - Torture-test changes. (Paul E. McKenney, Davidlohr Bueso) - Documentation updates. (Paul E. McKenney) Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-10-17Merge branches 'irq-urgent-for-linus' and 'timers-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq/timer fixes from Thomas Gleixner: "irq: a fix for the new hierarchical MSI interrupt handling which unbreaks PCI=n configurations. timers: a fix for the new hrtimer clock offset update mechanism to ensure that the boot time offset is respected" * 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: genirq/msi: Do not use pci_msi_[un]mask_irq as default methods * 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: timekeeping: Increment clock_was_set_seq in timekeeping_init()
2015-10-16ftrace: Clarify code for mod commandDmitry Safonov
"Not" is too abstract variable name - changed to clear_filter. Removed ftrace_match_module_records function: comparison with !* or * not does the general code in filter_parse_regex() as it works without mod command for sh# echo '!*' > /sys/kernel/debug/tracing/set_ftrace_filter Link: http://lkml.kernel.org/r/1443545176-3215-2-git-send-email-0x7f454c46@gmail.com Signed-off-by: Dmitry Safonov <0x7f454c46@gmail.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2015-10-16timekeeping: Increment clock_was_set_seq in timekeeping_init()Thomas Gleixner
timekeeping_init() can set the wall time offset, so we need to increment the clock_was_set_seq counter. That way hrtimers will pick up the early offset immediately. Otherwise on a machine which does not set wall time later in the boot process the hrtimer offset is stale at 0 and wall time timers are going to expire with a delay of 45 years. Fixes: 868a3e915f7f "hrtimer: Make offset update smarter" Reported-and-tested-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Stefan Liebler <stli@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: John Stultz <john.stultz@linaro.org>
2015-10-16genirq/msi: Do not use pci_msi_[un]mask_irq as default methodsMarc Zyngier
When we create a generic MSI domain, that MSI_FLAG_USE_DEF_CHIP_OPS is set, and that any of .mask or .unmask are NULL in the irq_chip structure, we set them to pci_msi_[un]mask_irq. This is a bad idea for at least two reasons: - PCI_MSI might not be selected, kernel fails to build (yes, this is legitimate, at least on arm64!) - This may not be a PCI/MSI domain at all (platform MSI, for example) Either way, this looks wrong. Move the overriding of mask/unmask to the PCI counterpart, and panic is any of these two methods is not set in the core code (they really should be present). Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Cc: Jiang Liu <jiang.liu@linux.intel.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Link: http://lkml.kernel.org/r/1444760085-27857-1-git-send-email-marc.zyngier@arm.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-10-16bpf: Need to call bpf_prog_uncharge_memlock from bpf_prog_putTom Herbert
Currently, is only called from __prog_put_rcu in the bpf_prog_release path. Need this to call this from bpf_prog_put also to get correct accounting. Fixes: aaac3ba95e4c8b49 ("bpf: charge user for creation of BPF maps and programs") Signed-off-by: Tom Herbert <tom@herbertland.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-15cgroup: drop cgroup__DEVEL__legacy_files_on_dflTejun Heo
Now that interfaces for the major three controllers - cpu, memory, io - are shaping up, there's no reason to have an option to force legacy files to show up on the unified hierarchy for testing. Drop it. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Li Zefan <lizefan@huawei.com> Cc: Johannes Weiner <hannes@cmpxchg.org>
2015-10-15cgroup: replace error handling in cgroup_init() with WARN_ON()sTejun Heo
The init sequence shouldn't fail short of bugs and even when it does it's better to continue with the rest of initialization and we were silently ignoring /proc/cgroups creation failure. Drop the explicit error handling and wrap sysfs_create_mount_point(), register_filesystem() and proc_create() with WARN_ON()s. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com> Cc: Johannes Weiner <hannes@cmpxchg.org>
2015-10-15cgroup: add cgroup_subsys->free() method and use it to fix pids controllerTejun Heo
pids controller is completely broken in that it uncharges when a task exits allowing zombies to escape resource control. With the recent updates, cgroup core now maintains cgroup association till task free and pids controller can be fixed by uncharging on free instead of exit. This patch adds cgroup_subsys->free() method and update pids controller to use it instead of ->exit() for uncharging. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Aleksa Sarai <cyphar@cyphar.com>
2015-10-15cgroup: keep zombies associated with their original cgroupsTejun Heo
cgroup_exit() is called when a task exits and disassociates the exiting task from its cgroups and half-attach it to the root cgroup. This is unnecessary and undesirable. No controller actually needs an exiting task to be disassociated with non-root cgroups. Both cpu and perf_event controllers update the association to the root cgroup from their exit callbacks just to keep consistent with the cgroup core behavior. Also, this disassociation makes it difficult to track resources held by zombies or determine where the zombies came from. Currently, pids controller is completely broken as it uncharges on exit and zombies always escape the resource restriction. With cgroup association being reset on exit, fixing it is pretty painful. There's no reason to reset cgroup membership on exit. The zombie can be removed from its css_set so that it doesn't show up on "cgroup.procs" and thus can't be migrated or interfere with cgroup removal. It can still pin and point to the css_set so that its cgroup membership is maintained. This patch makes cgroup core keep zombies associated with their cgroups at the time of exit. * Previous patches decoupled populated_cnt tracking from css_set lifetime, so a dying task can be simply unlinked from its css_set while pinning and pointing to the css_set. This keeps css_set association from task side alive while hiding it from "cgroup.procs" and populated_cnt tracking. The css_set reference is dropped when the task_struct is freed. * ->exit() callback no longer needs the css arguments as the associated css never changes once PF_EXITING is set. Removed. * cpu and perf_events controllers no longer need ->exit() callbacks. There's no reason to explicitly switch away on exit. The final schedule out is enough. The callbacks are removed. * On traditional hierarchies, nothing changes. "/proc/PID/cgroup" still reports "/" for all zombies. On the default hierarchy, "/proc/PID/cgroup" keeps reporting the cgroup that the task belonged to at the time of exit. If the cgroup gets removed before the task is reaped, " (deleted)" is appended. v2: Build brekage due to missing dummy cgroup_free() when !CONFIG_CGROUP fixed. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
2015-10-15cgroup: make css_set_rwsem a spinlock and rename it to css_set_lockTejun Heo
css_set_rwsem is the inner lock protecting css_sets and is accessed from hot paths such as fork and exit. Internally, it has no reason to be a rwsem or even mutex. There are no internal blocking operations while holding it. This was rwsem because css task iteration used to expose it to external iterator users. As the previous patch updated css task iteration such that the locking is not leaked to its users, there's no reason to keep it a rwsem. This patch converts css_set_rwsem to a spinlock and rename it to css_set_lock. It uses bh-safe operations as a planned usage needs to access it from RCU callback context. Signed-off-by: Tejun Heo <tj@kernel.org>
2015-10-15cgroup: don't hold css_set_rwsem across css task iterationTejun Heo
css_sets are synchronized through css_set_rwsem but the locking scheme is kinda bizarre. The hot paths - fork and exit - have to write lock the rwsem making the rw part pointless; furthermore, many readers already hold cgroup_mutex. One of the readers is css task iteration. It read locks the rwsem over the entire duration of iteration. This leads to silly locking behavior. When cpuset tries to migrate processes of a cgroup to a different NUMA node, css_set_rwsem is held across the entire migration attempt which can take a long time locking out forking, exiting and other cgroup operations. This patch updates css task iteration so that it locks css_set_rwsem only while the iterator is being advanced. css task iteration involves two levels - css_set and task iteration. As css_sets in use are practically immutable, simply pinning the current one is enough for resuming iteration afterwards. Task iteration is tricky as tasks may leave their css_set while iteration is in progress. This is solved by keeping track of active iterators and advancing them if their next task leaves its css_set. v2: put_task_struct() in css_task_iter_next() moved outside css_set_rwsem. A later patch will add cgroup operations to task_struct free path which may grab the same lock and this avoids deadlock possibilities. css_set_move_task() updated to use list_for_each_entry_safe() when walking task_iters and advancing them. This is necessary as advancing an iter may remove it from the list. Signed-off-by: Tejun Heo <tj@kernel.org>
2015-10-15cgroup: reorganize css_task_iter functionsTejun Heo
* Rename css_advance_task_iter() to css_task_iter_advance_css_set() and make it clear it->task_pos too at the end of the iteration. * Factor out css_task_iter_advance() from css_task_iter_next(). The new function whines if called on a terminated iterator. Except for the termination check, this is pure reorganization and doesn't introduce any behavior changes. This will help the planned locking update for css_task_iter. Signed-off-by: Tejun Heo <tj@kernel.org>
2015-10-15cgroup: factor out css_set_move_task()Tejun Heo
A task is associated and disassociated with its css_set in three places - during migration, after a new task is created and when a task exits. The first is handled by cgroup_task_migrate() and the latter two are open-coded. These are similar operations and spreading them over multiple places makes it harder to follow and update. This patch collects all task css_set [dis]association operations into css_set_move_task(). While css_set_move_task() may check whether populated state needs to be updated when not strictly necessary, the behavior is essentially equivalent before and after this patch. Signed-off-by: Tejun Heo <tj@kernel.org>
2015-10-15cgroup: keep css_set and task lists in chronological orderTejun Heo
css task iteration will be updated to not leak cgroup internal locking to iterator users. In preparation, update css_set and task lists to be in chronological order. For tasks, as migration path is already using list_splice_tail_init(), only cgroup_enable_task_cg_lists() and cgroup_post_fork() need updating. For css_sets, link_css_set() is the only place which needs to be updated. Signed-off-by: Tejun Heo <tj@kernel.org>