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2016-08-24perf/core: Use this_cpu_ptr() when stopping AUX eventsWill Deacon
When tearing down an AUX buf for an event via perf_mmap_close(), __perf_event_output_stop() is called on the event's CPU to ensure that trace generation is halted before the process of unmapping and freeing the buffer pages begins. The callback is performed via cpu_function_call(), which ensures that it runs with interrupts disabled and is therefore not preemptible. Unfortunately, the current code grabs the per-cpu context pointer using get_cpu_ptr(), which unnecessarily disables preemption and doesn't pair the call with put_cpu_ptr(), leading to a preempt_count() imbalance and a BUG when freeing the AUX buffer later on: WARNING: CPU: 1 PID: 2249 at kernel/events/ring_buffer.c:539 __rb_free_aux+0x10c/0x120 Modules linked in: [...] Call Trace: [<ffffffff813379dd>] dump_stack+0x4f/0x72 [<ffffffff81059ff6>] __warn+0xc6/0xe0 [<ffffffff8105a0c8>] warn_slowpath_null+0x18/0x20 [<ffffffff8112761c>] __rb_free_aux+0x10c/0x120 [<ffffffff81128163>] rb_free_aux+0x13/0x20 [<ffffffff8112515e>] perf_mmap_close+0x29e/0x2f0 [<ffffffff8111da30>] ? perf_iterate_ctx+0xe0/0xe0 [<ffffffff8115f685>] remove_vma+0x25/0x60 [<ffffffff81161796>] exit_mmap+0x106/0x140 [<ffffffff8105725c>] mmput+0x1c/0xd0 [<ffffffff8105cac3>] do_exit+0x253/0xbf0 [<ffffffff8105e32e>] do_group_exit+0x3e/0xb0 [<ffffffff81068d49>] get_signal+0x249/0x640 [<ffffffff8101c273>] do_signal+0x23/0x640 [<ffffffff81905f42>] ? _raw_write_unlock_irq+0x12/0x30 [<ffffffff81905f69>] ? _raw_spin_unlock_irq+0x9/0x10 [<ffffffff81901896>] ? __schedule+0x2c6/0x710 [<ffffffff810022a4>] exit_to_usermode_loop+0x74/0x90 [<ffffffff81002a56>] prepare_exit_to_usermode+0x26/0x30 [<ffffffff81906d1b>] retint_user+0x8/0x10 This patch uses this_cpu_ptr() instead of get_cpu_ptr(), since preemption is already disabled by the caller. Signed-off-by: Will Deacon <will.deacon@arm.com> Reviewed-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Fixes: 95ff4ca26c49 ("perf/core: Free AUX pages in unmap path") Link: http://lkml.kernel.org/r/20160824091905.GA16944@arm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-18perf/core: Check return value of the perf_event_read() IPIDavid Carrillo-Cisneros
The call to smp_call_function_single in perf_event_read() may fail if an invalid or not online CPU index is passed. Warn user if such bug is present and return error. Signed-off-by: David Carrillo-Cisneros <davidcc@google.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Kan Liang <kan.liang@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul Turner <pjt@google.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vegard Nossum <vegard.nossum@gmail.com> Cc: Vince Weaver <vincent.weaver@maine.edu> Link: http://lkml.kernel.org/r/1471467307-61171-2-git-send-email-davidcc@google.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-18perf/core: Enable mapping of the stop filtersMathieu Poirier
At this time the perf_addr_filter_needs_mmap() function will _not_ return true on a user space 'stop' filter. But stop filters need exactly the same kind of mapping that range and start filters get. Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Link: http://lkml.kernel.org/r/1468860187-318-4-git-send-email-mathieu.poirier@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-18perf/core: Update filters only on executable mmapMathieu Poirier
Function perf_event_mmap() is called by the MM subsystem each time part of a binary is loaded in memory. There can be several mapping for a binary, many times unrelated to the code section. Each time a section of a binary is mapped address filters are updated, event when the map doesn't pertain to the code section. The end result is that filters are configured based on the last map event that was received rather than the last mapping of the code segment. For example if we have an executable 'main' that calls library 'libcstest.so.1.0', and that we want to collect traces on code that is in that library. The perf cmd line for this scenario would be: perf record -e cs_etm// --filter 'filter 0x72c/0x40@/opt/lib/libcstest.so.1.0' --per-thread ./main Resulting in binaries being mapped this way: root@linaro-nano:~# cat /proc/1950/maps 00400000-00401000 r-xp 00000000 08:02 33169 /home/linaro/main 00410000-00411000 r--p 00000000 08:02 33169 /home/linaro/main 00411000-00412000 rw-p 00001000 08:02 33169 /home/linaro/main 7fa2464000-7fa2474000 rw-p 00000000 00:00 0 7fa2474000-7fa25a4000 r-xp 00000000 08:02 543 /lib/aarch64-linux-gnu/libc-2.21.so 7fa25a4000-7fa25b3000 ---p 00130000 08:02 543 /lib/aarch64-linux-gnu/libc-2.21.so 7fa25b3000-7fa25b7000 r--p 0012f000 08:02 543 /lib/aarch64-linux-gnu/libc-2.21.so 7fa25b7000-7fa25b9000 rw-p 00133000 08:02 543 /lib/aarch64-linux-gnu/libc-2.21.so 7fa25b9000-7fa25bd000 rw-p 00000000 00:00 0 7fa25bd000-7fa25be000 r-xp 00000000 08:02 38308 /opt/lib/libcstest.so.1.0 7fa25be000-7fa25cd000 ---p 00001000 08:02 38308 /opt/lib/libcstest.so.1.0 7fa25cd000-7fa25ce000 r--p 00000000 08:02 38308 /opt/lib/libcstest.so.1.0 7fa25ce000-7fa25cf000 rw-p 00001000 08:02 38308 /opt/lib/libcstest.so.1.0 7fa25cf000-7fa25eb000 r-xp 00000000 08:02 574 /lib/aarch64-linux-gnu/ld-2.21.so 7fa25ef000-7fa25f2000 rw-p 00000000 00:00 0 7fa25f7000-7fa25f9000 rw-p 00000000 00:00 0 7fa25f9000-7fa25fa000 r--p 00000000 00:00 0 [vvar] 7fa25fa000-7fa25fb000 r-xp 00000000 00:00 0 [vdso] 7fa25fb000-7fa25fc000 r--p 0001c000 08:02 574 /lib/aarch64-linux-gnu/ld-2.21.so 7fa25fc000-7fa25fe000 rw-p 0001d000 08:02 574 /lib/aarch64-linux-gnu/ld-2.21.so 7ff2ea8000-7ff2ec9000 rw-p 00000000 00:00 0 [stack] root@linaro-nano:~# Before 'main()' can execute 'libcstest.so.1.0' has to be loaded in memory. Once that has been done perf_event_mmap() has been called 4 times, with the last map starting at address 0x7fa25ce000 and the address filter configured to start filtering when the IP has passed over address 0x0x7fa25ce72c (0x7fa25ce000 + 0x72c). But that is wrong since the code segment for library 'libcstest.so.1.0' as been mapped at 0x7fa25bd000, resulting in traces not being collected. This patch corrects the situation by requesting that address filters be updated only if the mapped event is for a code segment. Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Link: http://lkml.kernel.org/r/1468860187-318-3-git-send-email-mathieu.poirier@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-18perf/core: Fix file name handling for start/stop filtersMathieu Poirier
Binary file names have to be supplied for both range and start/stop filters but the current code only processes the filename if an address range filter is specified. This code adds processing of the filename for start/stop filters. Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Link: http://lkml.kernel.org/r/1468860187-318-2-git-send-email-mathieu.poirier@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-18perf/core: Fix event_function_local()Peter Zijlstra
Vincent reported triggering the WARN_ON_ONCE() in event_function_local(). While thinking through cases I noticed that by using event_function() directly, we miss the inactive case usually handled by event_function_call(). Therefore construct a blend of event_function_call() and event_function() that handles the cases relevant to event_function_local(). Reported-by: Vince Weaver <vincent.weaver@maine.edu> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org # 4.5+ Fixes: fae3fde65138 ("perf: Collapse and fix event_function_call() users") Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-18uprobes: Fix the memcg accountingOleg Nesterov
__replace_page() wronlgy calls mem_cgroup_cancel_charge() in "success" path, it should only do this if page_check_address() fails. This means that every enable/disable leads to unbalanced mem_cgroup_uncharge() from put_page(old_page), it is trivial to underflow the page_counter->count and trigger OOM. Reported-and-tested-by: Brenden Blanco <bblanco@plumgrid.com> Signed-off-by: Oleg Nesterov <oleg@redhat.com> Reviewed-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Michal Hocko <mhocko@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vladimir Davydov <vdavydov@virtuozzo.com> Cc: stable@vger.kernel.org # 3.17+ Fixes: 00501b531c47 ("mm: memcontrol: rewrite charge API") Link: http://lkml.kernel.org/r/20160817153629.GB29724@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-10perf/core: Set cgroup in CPU contexts for new cgroup eventsDavid Carrillo-Cisneros
There's a perf stat bug easy to observer on a machine with only one cgroup: $ perf stat -e cycles -I 1000 -C 0 -G / # time counts unit events 1.000161699 <not counted> cycles / 2.000355591 <not counted> cycles / 3.000565154 <not counted> cycles / 4.000951350 <not counted> cycles / We'd expect some output there. The underlying problem is that there is an optimization in perf_cgroup_sched_{in,out}() that skips the switch of cgroup events if the old and new cgroups in a task switch are the same. This optimization interacts with the current code in two ways that cause a CPU context's cgroup (cpuctx->cgrp) to be NULL even if a cgroup event matches the current task. These are: 1. On creation of the first cgroup event in a CPU: In current code, cpuctx->cpu is only set in perf_cgroup_sched_in, but due to the aforesaid optimization, perf_cgroup_sched_in will run until the next cgroup switches in that CPU. This may happen late or never happen, depending on system's number of cgroups, CPU load, etc. 2. On deletion of the last cgroup event in a cpuctx: In list_del_event, cpuctx->cgrp is set NULL. Any new cgroup event will not be sched in because cpuctx->cgrp == NULL until a cgroup switch occurs and perf_cgroup_sched_in is executed (updating cpuctx->cgrp). This patch fixes both problems by setting cpuctx->cgrp in list_add_event, mirroring what list_del_event does when removing a cgroup event from CPU context, as introduced in: commit 68cacd29167b ("perf_events: Fix stale ->cgrp pointer in update_cgrp_time_from_cpuctx()") With this patch, cpuctx->cgrp is always set/clear when installing/removing the first/last cgroup event in/from the CPU context. With cpuctx->cgrp correctly set, event_filter_match works as intended when events are sched in/out. After the fix, the output is as expected: $ perf stat -e cycles -I 1000 -a -G / # time counts unit events 1.004699159 627342882 cycles / 2.007397156 615272690 cycles / 3.010019057 616726074 cycles / Signed-off-by: David Carrillo-Cisneros <davidcc@google.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Kan Liang <kan.liang@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul Turner <pjt@google.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vegard Nossum <vegard.nossum@gmail.com> Cc: Vince Weaver <vincent.weaver@maine.edu> Link: http://lkml.kernel.org/r/1470124092-113192-1-git-send-email-davidcc@google.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-10perf/core: Fix sideband list-iteration vs. event ordering NULL pointer ↵Peter Zijlstra
deference crash Vegard Nossum reported that perf fuzzing generates a NULL pointer dereference crash: > Digging a bit deeper into this, it seems the event itself is getting > created by perf_event_open() and it gets added to the pmu_event_list > through: > > perf_event_open() > - perf_event_alloc() > - account_event() > - account_pmu_sb_event() > - attach_sb_event() > > so at this point the event is being attached but its ->ctx is still > NULL. It seems like ->ctx is set just a bit later in > perf_event_open(), though. > > But before that, __schedule() comes along and creates a stack trace > similar to the one above: > > __schedule() > - __perf_event_task_sched_out() > - perf_iterate_sb() > - perf_iterate_sb_cpu() > - event_filter_match() > - perf_cgroup_match() > - __get_cpu_context() > - (dereference ctx which is NULL) > > So I guess the question is... should the event be attached (= put on > the list) before ->ctx gets set? Or should the cgroup code check for a > NULL ->ctx? The latter seems like the simplest solution. Moving the list-add later creates a bit of a mess. Reported-by: Vegard Nossum <vegard.nossum@gmail.com> Tested-by: Vegard Nossum <vegard.nossum@gmail.com> Tested-by: Vince Weaver <vincent.weaver@maine.edu> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: David Carrillo-Cisneros <davidcc@google.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Kan Liang <kan.liang@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Fixes: f2fb6bef9251 ("perf/core: Optimize side-band event delivery") Link: http://lkml.kernel.org/r/20160804123724.GN6862@twins.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-02perf/core: Change log level for duration warning to KERN_INFODavid Ahern
When the perf interrupt handler exceeds a threshold warning messages are displayed on console: [12739.31793] perf interrupt took too long (2504 > 2500), lowering kernel.perf_event_max_sample_rate to 50000 [71340.165065] perf interrupt took too long (5005 > 5000), lowering kernel.perf_event_max_sample_rate to 25000 Many customers and users are confused by the message wondering if something is wrong or they need to take action to fix a problem. Since a user can not do anything to fix the issue, the message is really more informational than a warning. Adjust the log level accordingly. Signed-off-by: David Ahern <dsa@cumulusnetworks.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1470084569-438-1-git-send-email-dsa@cumulusnetworks.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-29Merge branch 'smp-hotplug-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull smp hotplug updates from Thomas Gleixner: "This is the next part of the hotplug rework. - Convert all notifiers with a priority assigned - Convert all CPU_STARTING/DYING notifiers The final removal of the STARTING/DYING infrastructure will happen when the merge window closes. Another 700 hundred line of unpenetrable maze gone :)" * 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (70 commits) timers/core: Correct callback order during CPU hot plug leds/trigger/cpu: Move from CPU_STARTING to ONLINE level powerpc/numa: Convert to hotplug state machine arm/perf: Fix hotplug state machine conversion irqchip/armada: Avoid unused function warnings ARC/time: Convert to hotplug state machine clocksource/atlas7: Convert to hotplug state machine clocksource/armada-370-xp: Convert to hotplug state machine clocksource/exynos_mct: Convert to hotplug state machine clocksource/arm_global_timer: Convert to hotplug state machine rcu: Convert rcutree to hotplug state machine KVM/arm/arm64/vgic-new: Convert to hotplug state machine smp/cfd: Convert core to hotplug state machine x86/x2apic: Convert to CPU hotplug state machine profile: Convert to hotplug state machine timers/core: Convert to hotplug state machine hrtimer: Convert to hotplug state machine x86/tboot: Convert to hotplug state machine arm64/armv8 deprecated: Convert to hotplug state machine hwtracing/coresight-etm4x: Convert to hotplug state machine ...
2016-07-27Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-nextLinus Torvalds
Pull networking updates from David Miller: 1) Unified UDP encapsulation offload methods for drivers, from Alexander Duyck. 2) Make DSA binding more sane, from Andrew Lunn. 3) Support QCA9888 chips in ath10k, from Anilkumar Kolli. 4) Several workqueue usage cleanups, from Bhaktipriya Shridhar. 5) Add XDP (eXpress Data Path), essentially running BPF programs on RX packets as soon as the device sees them, with the option to mirror the packet on TX via the same interface. From Brenden Blanco and others. 6) Allow qdisc/class stats dumps to run lockless, from Eric Dumazet. 7) Add VLAN support to b53 and bcm_sf2, from Florian Fainelli. 8) Simplify netlink conntrack entry layout, from Florian Westphal. 9) Add ipv4 forwarding support to mlxsw spectrum driver, from Ido Schimmel, Yotam Gigi, and Jiri Pirko. 10) Add SKB array infrastructure and convert tun and macvtap over to it. From Michael S Tsirkin and Jason Wang. 11) Support qdisc packet injection in pktgen, from John Fastabend. 12) Add neighbour monitoring framework to TIPC, from Jon Paul Maloy. 13) Add NV congestion control support to TCP, from Lawrence Brakmo. 14) Add GSO support to SCTP, from Marcelo Ricardo Leitner. 15) Allow GRO and RPS to function on macsec devices, from Paolo Abeni. 16) Support MPLS over IPV4, from Simon Horman. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1622 commits) xgene: Fix build warning with ACPI disabled. be2net: perform temperature query in adapter regardless of its interface state l2tp: Correctly return -EBADF from pppol2tp_getname. net/mlx5_core/health: Remove deprecated create_singlethread_workqueue net: ipmr/ip6mr: update lastuse on entry change macsec: ensure rx_sa is set when validation is disabled tipc: dump monitor attributes tipc: add a function to get the bearer name tipc: get monitor threshold for the cluster tipc: make cluster size threshold for monitoring configurable tipc: introduce constants for tipc address validation net: neigh: disallow transition to NUD_STALE if lladdr is unchanged in neigh_update() MAINTAINERS: xgene: Add driver and documentation path Documentation: dtb: xgene: Add MDIO node dtb: xgene: Add MDIO node drivers: net: xgene: ethtool: Use phy_ethtool_gset and sset drivers: net: xgene: Use exported functions drivers: net: xgene: Enable MDIO driver drivers: net: xgene: Add backward compatibility drivers: net: phy: xgene: Add MDIO driver ...
2016-07-25bpf, events: fix offset in skb copy handlerDaniel Borkmann
This patch fixes the __output_custom() routine we currently use with bpf_skb_copy(). I missed that when len is larger than the size of the current handle, we can issue multiple invocations of copy_func, and __output_custom() advances destination but also source buffer by the written amount of bytes. When we have __output_custom(), this is actually wrong since in that case the source buffer points to a non-linear object, in our case an skb, which the copy_func helper is supposed to walk. Therefore, since this is non-linear we thus need to pass the offset into the helper, so that copy_func can use it for extracting the data from the source object. Therefore, adjust the callback signatures properly and pass offset into the skb_header_pointer() invoked from bpf_skb_copy() callback. The __DEFINE_OUTPUT_COPY_BODY() is adjusted to accommodate for two things: i) to pass in whether we should advance source buffer or not; this is a compile-time constant condition, ii) to pass in the offset for __output_custom(), which we do with help of __VA_ARGS__, so everything can stay inlined as is currently. Both changes allow for adapting the __output_* fast-path helpers w/o extra overhead. Fixes: 555c8a8623a3 ("bpf: avoid stack copy and use skb ctx for event output") Fixes: 7e3f977edd0b ("perf, events: add non-linear data support for raw records") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-07-24Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Just several instances of overlapping changes. Signed-off-by: David S. Miller <davem@davemloft.net>
2016-07-15perf, events: add non-linear data support for raw recordsDaniel Borkmann
This patch adds support for non-linear data on raw records. It extends raw records to have one or multiple fragments that will be written linearly into the ring slot, where each fragment can optionally have a custom callback handler to walk and extract complex, possibly non-linear data. If a callback handler is provided for a fragment, then the new __output_custom() will be used instead of __output_copy() for the perf_output_sample() part. perf_prepare_sample() does all the size calculation only once, so perf_output_sample() doesn't need to redo the same work anymore, meaning real_size and padding will be cached in the raw record. The raw record becomes 32 bytes in size without holes; to not increase it further and to avoid doing unnecessary recalculations in fast-path, we can reuse next pointer of the last fragment, idea here is borrowed from ZERO_OR_NULL_PTR(), which should keep the perf_output_sample() path for PERF_SAMPLE_RAW minimal. This facility is needed for BPF's event output helper as a first user that will, in a follow-up, add an additional perf_raw_frag to its perf_raw_record in order to be able to more efficiently dump skb context after a linear head meta data related to it. skbs can be non-linear and thus need a custom output function to dump buffers. Currently, the skb data needs to be copied twice; with the help of __output_custom() this work only needs to be done once. Future users could be things like XDP/BPF programs that work on different context though and would thus also have a different callback function. The few users of raw records are adapted to initialize their frag data from the raw record itself, no change in behavior for them. The code is based upon a PoC diff provided by Peter Zijlstra [1]. [1] http://thread.gmane.org/gmane.linux.network/421294 Suggested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-07-14perf/core: Convert to hotplug state machineThomas Gleixner
Actually a nice symmetric startup/teardown pair which fits properly into the state machine concept. In the long run we should be able to invoke the startup callback for the boot CPU via the state machine and get rid of the init function which invokes it on the boot CPU. Note: This comes actually before the perf hardware callbacks. In the notifier model the hardware callbacks have a higher priority than the core callback. But that's solely for CPU offline so that hardware migration of events happens before the core is notified about the outgoing CPU. With the symetric state array model we have the following ordering: UP: core -> hardware DOWN: hardware -> core Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de> Reviewed-by: Sebastian Siewior <bigeasy@linutronix.de> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: rt@linutronix.de Link: http://lkml.kernel.org/r/20160713153333.587514098@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-07Merge branch 'perf/urgent' into perf/core, to pick up fixes before merging ↵Ingo Molnar
new changes Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-07perf/core: Fix pmu::filter_match for SW-led groupsMark Rutland
The following commit: 66eb579e66ec ("perf: allow for PMU-specific event filtering") added the pmu::filter_match() callback. This was intended to avoid HW constraints on events from resulting in extremely pessimistic scheduling. However, pmu::filter_match() is only called for the leader of each event group. When the leader is a SW event, we do not filter the groups, and may fail at pmu::add() time, and when this happens we'll give up on scheduling any event groups later in the list until they are rotated ahead of the failing group. This can result in extremely sub-optimal event scheduling behaviour, e.g. if running the following on a big.LITTLE platform: $ taskset -c 0 ./perf stat \ -e 'a57{context-switches,armv8_cortex_a57/config=0x11/}' \ -e 'a53{context-switches,armv8_cortex_a53/config=0x11/}' \ ls <not counted> context-switches (0.00%) <not counted> armv8_cortex_a57/config=0x11/ (0.00%) 24 context-switches (37.36%) 57589154 armv8_cortex_a53/config=0x11/ (37.36%) Here the 'a53' event group was always eligible to be scheduled, but the 'a57' group never eligible to be scheduled, as the task was always affine to a Cortex-A53 CPU. The SW (group leader) event in the 'a57' group was eligible, but the HW event failed at pmu::add() time, resulting in ctx_flexible_sched_in giving up on scheduling further groups with HW events. One way of avoiding this is to check pmu::filter_match() on siblings as well as the group leader. If any of these fail their pmu::filter_match() call, we must skip the entire group before attempting to add any events. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Fixes: 66eb579e66ec ("perf: allow for PMU-specific event filtering") Link: http://lkml.kernel.org/r/1465917041-15339-1-git-send-email-mark.rutland@arm.com [ Small readability edits. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-01bpf: generally move prog destruction to RCU deferralDaniel Borkmann
Jann Horn reported following analysis that could potentially result in a very hard to trigger (if not impossible) UAF race, to quote his event timeline: - Set up a process with threads T1, T2 and T3 - Let T1 set up a socket filter F1 that invokes another filter F2 through a BPF map [tail call] - Let T1 trigger the socket filter via a unix domain socket write, don't wait for completion - Let T2 call PERF_EVENT_IOC_SET_BPF with F2, don't wait for completion - Now T2 should be behind bpf_prog_get(), but before bpf_prog_put() - Let T3 close the file descriptor for F2, dropping the reference count of F2 to 2 - At this point, T1 should have looked up F2 from the map, but not finished executing it - Let T3 remove F2 from the BPF map, dropping the reference count of F2 to 1 - Now T2 should call bpf_prog_put() (wrong BPF program type), dropping the reference count of F2 to 0 and scheduling bpf_prog_free_deferred() via schedule_work() - At this point, the BPF program could be freed - BPF execution is still running in a freed BPF program While at PERF_EVENT_IOC_SET_BPF time it's only guaranteed that the perf event fd we're doing the syscall on doesn't disappear from underneath us for whole syscall time, it may not be the case for the bpf fd used as an argument only after we did the put. It needs to be a valid fd pointing to a BPF program at the time of the call to make the bpf_prog_get() and while T2 gets preempted, F2 must have dropped reference to 1 on the other CPU. The fput() from the close() in T3 should also add additionally delay to the reference drop via exit_task_work() when bpf_prog_release() gets called as well as scheduling bpf_prog_free_deferred(). That said, it makes nevertheless sense to move the BPF prog destruction generally after RCU grace period to guarantee that such scenario above, but also others as recently fixed in ceb56070359b ("bpf, perf: delay release of BPF prog after grace period") with regards to tail calls won't happen. Integrating bpf_prog_free_deferred() directly into the RCU callback is not allowed since the invocation might happen from either softirq or process context, so we're not permitted to block. Reviewing all bpf_prog_put() invocations from eBPF side (note, cBPF -> eBPF progs don't use this for their destruction) with call_rcu() look good to me. Since we don't know whether at the time of attaching the program, we're already part of a tail call map, we need to use RCU variant. However, due to this, there won't be severely more stress on the RCU callback queue: situations with above bpf_prog_get() and bpf_prog_put() combo in practice normally won't lead to releases, but even if they would, enough effort/ cycles have to be put into loading a BPF program into the kernel already. Reported-by: Jann Horn <jannh@google.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-29Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netLinus Torvalds
Pull networking fixes from David Miller: "I've been traveling so this accumulates more than week or so of bug fixing. It perhaps looks a little worse than it really is. 1) Fix deadlock in ath10k driver, from Ben Greear. 2) Increase scan timeout in iwlwifi, from Luca Coelho. 3) Unbreak STP by properly reinjecting STP packets back into the stack. Regression fix from Ido Schimmel. 4) Mediatek driver fixes (missing malloc failure checks, leaking of scratch memory, wrong indexing when mapping TX buffers, etc.) from John Crispin. 5) Fix endianness bug in icmpv6_err() handler, from Hannes Frederic Sowa. 6) Fix hashing of flows in UDP in the ruseport case, from Xuemin Su. 7) Fix netlink notifications in ovs for tunnels, delete link messages are never emitted because of how the device registry state is handled. From Nicolas Dichtel. 8) Conntrack module leaks kmemcache on unload, from Florian Westphal. 9) Prevent endless jump loops in nft rules, from Liping Zhang and Pablo Neira Ayuso. 10) Not early enough spinlock initialization in mlx4, from Eric Dumazet. 11) Bind refcount leak in act_ipt, from Cong WANG. 12) Missing RCU locking in HTB scheduler, from Florian Westphal. 13) Several small MACSEC bug fixes from Sabrina Dubroca (missing RCU barrier, using heap for SG and IV, and erroneous use of async flag when allocating AEAD conext.) 14) RCU handling fix in TIPC, from Ying Xue. 15) Pass correct protocol down into ipv4_{update_pmtu,redirect}() in SIT driver, from Simon Horman. 16) Socket timer deadlock fix in TIPC from Jon Paul Maloy. 17) Fix potential deadlock in team enslave, from Ido Schimmel. 18) Memory leak in KCM procfs handling, from Jiri Slaby. 19) ESN generation fix in ipv4 ESP, from Herbert Xu. 20) Fix GFP_KERNEL allocations with locks held in act_ife, from Cong WANG. 21) Use after free in netem, from Eric Dumazet. 22) Uninitialized last assert time in multicast router code, from Tom Goff. 23) Skip raw sockets in sock_diag destruction broadcast, from Willem de Bruijn. 24) Fix link status reporting in thunderx, from Sunil Goutham. 25) Limit resegmentation of retransmit queue so that we do not retransmit too large GSO frames. From Eric Dumazet. 26) Delay bpf program release after grace period, from Daniel Borkmann" * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (141 commits) openvswitch: fix conntrack netlink event delivery qed: Protect the doorbell BAR with the write barriers. neigh: Explicitly declare RCU-bh read side critical section in neigh_xmit() e1000e: keep VLAN interfaces functional after rxvlan off cfg80211: fix proto in ieee80211_data_to_8023 for frames without LLC header qlcnic: use the correct ring in qlcnic_83xx_process_rcv_ring_diag() bpf, perf: delay release of BPF prog after grace period net: bridge: fix vlan stats continue counter tcp: do not send too big packets at retransmit time ibmvnic: fix to use list_for_each_safe() when delete items net: thunderx: Fix TL4 configuration for secondary Qsets net: thunderx: Fix link status reporting net/mlx5e: Reorganize ethtool statistics net/mlx5e: Fix number of PFC counters reported to ethtool net/mlx5e: Prevent adding the same vxlan port net/mlx5e: Check for BlueFlame capability before allocating SQ uar net/mlx5e: Change enum to better reflect usage net/mlx5: Add ConnectX-5 PCIe 4.0 to list of supported devices net/mlx5: Update command strings net: marvell: Add separate config ANEG function for Marvell 88E1111 ...
2016-06-29bpf, perf: delay release of BPF prog after grace periodDaniel Borkmann
Commit dead9f29ddcc ("perf: Fix race in BPF program unregister") moved destruction of BPF program from free_event_rcu() callback to __free_event(), which is problematic if used with tail calls: if prog A is attached as trace event directly, but at the same time present in a tail call map used by another trace event program elsewhere, then we need to delay destruction via RCU grace period since it can still be in use by the program doing the tail call (the prog first needs to be dropped from the tail call map, then trace event with prog A attached destroyed, so we get immediate destruction). Fixes: dead9f29ddcc ("perf: Fix race in BPF program unregister") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Cc: Jann Horn <jann@thejh.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-14Merge branch 'linus' into perf/core, to pick up fixes before merging new changesIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-06-10Merge branch 'perf-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf fixes from Ingo Molnar: "A handful of tooling fixes, two PMU driver fixes and a cleanup of redundant code that addresses a security analyzer false positive" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf/core: Remove a redundant check perf/x86/intel/uncore: Remove SBOX support for Broadwell server perf ctf: Convert invalid chars in a string before set value perf record: Fix crash when kptr is restricted perf symbols: Check kptr_restrict for root perf/x86/intel/rapl: Fix pmus free during cleanup
2016-06-08perf/core: Remove a redundant checkAlexander Shishkin
There is no way to end up in _free_event() with event::pmu being NULL. The latter is initialized in event allocation path and remains set forever. In case of allocation failure, the error path doesn't use _free_event(). Having the check, however, suggests that it is possible to have a event::pmu==NULL situation in _free_event() and confuses the robots. This patch gets rid of the check. Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: eranian@google.com Cc: vince@deater.net Link: http://lkml.kernel.org/r/1465303455-26032-1-git-send-email-alexander.shishkin@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-06-08Merge branch 'linus' into perf/core, to refresh the branchIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-06-08perf/core: Fix crash due to account/unaccount_sb_event() inconsistencyDavid Carrillo-Cisneros
unaccount_pmu_sb_event() did not check for attributes in event->attr before calling detach_sb_event(), while account_pmu_event() did. This caused NULL pointer reference in cgroup events that did not have any of the attributes checked by account_pmu_event(). To trigger the bug just wait for a cgroup event to terminate, e.g.: $ mkdir /dev/cgroup/devices/test $ perf stat -e cycles -a -G test sleep 0 ... see crash ... Signed-off-by: David Carrillo-Cisneros <davidcc@google.com> Reviewed-by: Stephane Eranian <eranian@google.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Kan Liang <kan.liang@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Zheng <zheng.z.yan@intel.com> Link: http://lkml.kernel.org/r/1464809585-66072-1-git-send-email-davidcc@google.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-06-03perf/abi: Change the errno for sampling event not supported in hardwareVineet Gupta
Change the return code for sampling event not supported from -ENOTSUPP to -EOPNOTSUPP. This allows userspace to identify this case specifically, instead of printing the catch-all error message it did previously. Technically this is an ABI change, but we think we can get away with it. Old behavior: ------- | # perf record ls | Error: | The sys_perf_event_open() syscall returned with 524 (Unknown error 524) | for event (cycles:ppp). | /bin/dmesg may provide additional information. | No CONFIG_PERF_EVENTS=y kernel support configured? New behavior: ------- | # perf record ls | Error: | PMU Hardware doesn't support sampling/overflow-interrupts. Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: <acme@redhat.com> Cc: <linux-snps-arc@lists.infradead.org> Cc: <vincent.weaver@maine.edu> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: Vineet Gupta <Vineet.Gupta1@synopsys.com> Link: http://lkml.kernel.org/r/1462786660-2900-3-git-send-email-vgupta@synopsys.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-06-03perf/core: Fix implicitly enable dynamic interrupt throttleKan Liang
This patch fixes an issue which was introduced by commit: 91a612eea9a3 ("perf/core: Fix dynamic interrupt throttle") ... which commit unconditionally sets the perf_sample_allowed_ns value to !0. But that could trigger a bug in the following corner case: The user can disable the dynamic interrupt throttle mechanism by setting perf_cpu_time_max_percent to 0. Then they change perf_event_max_sample_rate. For this case, the mechanism will be enabled implicitly, because perf_sample_allowed_ns becomes !0 - which is not what we want. This patch only updates perf_sample_allowed_ns when the dynamic interrupt throttle mechanism is enabled. Signed-off-by: Kan Liang <kan.liang@intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: acme@kernel.org Link: http://lkml.kernel.org/r/1462260366-3160-1-git-send-email-kan.liang@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-06-03perf/core: Rename the perf_event_aux*() APIs to perf_event_sb*(), to ↵Peter Zijlstra
separate them from AUX ring-buffer records There are now two different things called AUX in perf, the infrastructure to deliver the mmap/comm/task records and the AUX part in the mmap buffer (with associated AUX_RECORD). Since the former is internal, rename it to side-band to reduce the confusion factor. No change in functionality. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-06-03perf/core: Optimize side-band event deliveryKan Liang
The perf_event_aux() function iterates all PMUs and all events in their respective per-CPU contexts to find the events to deliver side-band records to. For example, the brk test case in lkp triggers many mmap() operations, which, if we're also running perf, results in many perf_event_aux() invocations. If we enable uncore PMU support (even when uncore events are not used), dozens of uncore PMUs will be iterated, which can significantly decrease brk_test's throughput. For example, the brk throughput: without uncore PMUs: 2647573 ops_per_sec with uncore PMUs: 1768444 ops_per_sec ... a 33% reduction. To get at the per-CPU events that need side-band records, this patch puts these events on a per-CPU list, this avoids iterating the PMUs and any events that do not need side-band records. Per task events are unchanged to avoid extra overhead on the context switch paths. Suggested-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reported-by: Huang, Ying <ying.huang@linux.intel.com> Signed-off-by: Kan Liang <kan.liang@intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Link: http://lkml.kernel.org/r/1458757477-3781-1-git-send-email-kan.liang@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-05-30perf core: Per event callchain limitArnaldo Carvalho de Melo
Additionally to being able to control the system wide maximum depth via /proc/sys/kernel/perf_event_max_stack, now we are able to ask for different depths per event, using perf_event_attr.sample_max_stack for that. This uses an u16 hole at the end of perf_event_attr, that, when perf_event_attr.sample_type has the PERF_SAMPLE_CALLCHAIN, if sample_max_stack is zero, means use perf_event_max_stack, otherwise it'll be bounds checked under callchain_mutex. Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Brendan Gregg <brendan.d.gregg@gmail.com> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: He Kuang <hekuang@huawei.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Milian Wolff <milian.wolff@kdab.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: Wang Nan <wangnan0@huawei.com> Cc: Zefan Li <lizefan@huawei.com> Link: http://lkml.kernel.org/n/tip-kolmn1yo40p7jhswxwrc7rrd@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-05-26Merge branch 'perf-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf updates from Ingo Molnar: "Mostly tooling and PMU driver fixes, but also a number of late updates such as the reworking of the call-chain size limiting logic to make call-graph recording more robust, plus tooling side changes for the new 'backwards ring-buffer' extension to the perf ring-buffer" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (34 commits) perf record: Read from backward ring buffer perf record: Rename variable to make code clear perf record: Prevent reading invalid data in record__mmap_read perf evlist: Add API to pause/resume perf trace: Use the ptr->name beautifier as default for "filename" args perf trace: Use the fd->name beautifier as default for "fd" args perf report: Add srcline_from/to branch sort keys perf evsel: Record fd into perf_mmap perf evsel: Add overwrite attribute and check write_backward perf tools: Set buildid dir under symfs when --symfs is provided perf trace: Only auto set call-graph to "dwarf" when syscalls are being traced perf annotate: Sort list of recognised instructions perf annotate: Fix identification of ARM blt and bls instructions perf tools: Fix usage of max_stack sysctl perf callchain: Stop validating callchains by the max_stack sysctl perf trace: Fix exit_group() formatting perf top: Use machine->kptr_restrict_warned perf trace: Warn when trying to resolve kernel addresses with kptr_restrict=1 perf machine: Do not bail out if not managing to read ref reloc symbol perf/x86/intel/p4: Trival indentation fix, remove space ...
2016-05-24uprobes: wait for mmap_sem for write killableMichal Hocko
xol_add_vma needs mmap_sem for write. If the waiting task gets killed by the oom killer it would block oom_reaper from asynchronous address space reclaim and reduce the chances of timely OOM resolving. Wait for the lock in the killable mode and return with EINTR if the task got killed while waiting. Do not warn in dup_xol_work if __create_xol_area failed due to fatal signal pending because this is usually considered a kernel issue. Signed-off-by: Michal Hocko <mhocko@suse.com> Acked-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-23x86: remove more uaccess_32.h complexityLinus Torvalds
I'm looking at trying to possibly merge the 32-bit and 64-bit versions of the x86 uaccess.h implementation, but first this needs to be cleaned up. For example, the 32-bit version of "__copy_from_user_inatomic()" is mostly the special cases for the constant size, and it's actually almost never relevant. Most users aren't actually using a constant size anyway, and the few cases that do small constant copies are better off just using __get_user() instead. So get rid of the unnecessary complexity. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-17Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-nextLinus Torvalds
Pull networking updates from David Miller: "Highlights: 1) Support SPI based w5100 devices, from Akinobu Mita. 2) Partial Segmentation Offload, from Alexander Duyck. 3) Add GMAC4 support to stmmac driver, from Alexandre TORGUE. 4) Allow cls_flower stats offload, from Amir Vadai. 5) Implement bpf blinding, from Daniel Borkmann. 6) Optimize _ASYNC_ bit twiddling on sockets, unless the socket is actually using FASYNC these atomics are superfluous. From Eric Dumazet. 7) Run TCP more preemptibly, also from Eric Dumazet. 8) Support LED blinking, EEPROM dumps, and rxvlan offloading in mlx5e driver, from Gal Pressman. 9) Allow creating ppp devices via rtnetlink, from Guillaume Nault. 10) Improve BPF usage documentation, from Jesper Dangaard Brouer. 11) Support tunneling offloads in qed, from Manish Chopra. 12) aRFS offloading in mlx5e, from Maor Gottlieb. 13) Add RFS and RPS support to SCTP protocol, from Marcelo Ricardo Leitner. 14) Add MSG_EOR support to TCP, this allows controlling packet coalescing on application record boundaries for more accurate socket timestamp sampling. From Martin KaFai Lau. 15) Fix alignment of 64-bit netlink attributes across the board, from Nicolas Dichtel. 16) Per-vlan stats in bridging, from Nikolay Aleksandrov. 17) Several conversions of drivers to ethtool ksettings, from Philippe Reynes. 18) Checksum neutral ILA in ipv6, from Tom Herbert. 19) Factorize all of the various marvell dsa drivers into one, from Vivien Didelot 20) Add VF support to qed driver, from Yuval Mintz" * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1649 commits) Revert "phy dp83867: Fix compilation with CONFIG_OF_MDIO=m" Revert "phy dp83867: Make rgmii parameters optional" r8169: default to 64-bit DMA on recent PCIe chips phy dp83867: Make rgmii parameters optional phy dp83867: Fix compilation with CONFIG_OF_MDIO=m bpf: arm64: remove callee-save registers use for tmp registers asix: Fix offset calculation in asix_rx_fixup() causing slow transmissions switchdev: pass pointer to fib_info instead of copy net_sched: close another race condition in tcf_mirred_release() tipc: fix nametable publication field in nl compat drivers: net: Don't print unpopulated net_device name qed: add support for dcbx. ravb: Add missing free_irq() calls to ravb_close() qed: Remove a stray tab net: ethernet: fec-mpc52xx: use phy_ethtool_{get|set}_link_ksettings net: ethernet: fec-mpc52xx: use phydev from struct net_device bpf, doc: fix typo on bpf_asm descriptions stmmac: hardware TX COE doesn't work when force_thresh_dma_mode is set net: ethernet: fs-enet: use phy_ethtool_{get|set}_link_ksettings net: ethernet: fs-enet: use phydev from struct net_device ...
2016-05-17perf core: Separate accounting of contexts and real addresses in a stack traceArnaldo Carvalho de Melo
The perf_sample->ip_callchain->nr value includes all the entries in the ip_callchain->ip[] array, real addresses and PERF_CONTEXT_{KERNEL,USER,etc}, while what the user expects is that what is in the kernel.perf_event_max_stack sysctl or in the upcoming per event perf_event_attr.sample_max_stack knob be honoured in terms of IP addresses in the stack trace. So allocate a bunch of extra entries for contexts, and do the accounting via perf_callchain_entry_ctx struct members. A new sysctl, kernel.perf_event_max_contexts_per_stack is also introduced for investigating possible bugs in the callchain implementation by some arch. Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Brendan Gregg <brendan.d.gregg@gmail.com> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: He Kuang <hekuang@huawei.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Milian Wolff <milian.wolff@kdab.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: Wang Nan <wangnan0@huawei.com> Cc: Zefan Li <lizefan@huawei.com> Link: http://lkml.kernel.org/n/tip-3b4wnqk340c4sg4gwkfdi9yk@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-05-17perf core: Add perf_callchain_store_context() helperArnaldo Carvalho de Melo
We need have different helpers to account how many contexts we have in the sample and for real addresses, so do it now as a prep patch, to ease review. Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/n/tip-q964tnyuqrxw5gld18vizs3c@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-05-17perf core: Add a 'nr' field to perf_event_callchain_contextArnaldo Carvalho de Melo
We will use it to count how many addresses are in the entry->ip[] array, excluding PERF_CONTEXT_{KERNEL,USER,etc} entries, so that we can really return the number of entries specified by the user via the relevant sysctl, kernel.perf_event_max_contexts, or via the per event perf_event_attr.sample_max_stack knob. This way we keep the perf_sample->ip_callchain->nr meaning, that is the number of entries, be it real addresses or PERF_CONTEXT_ entries, while honouring the max_stack knobs, i.e. the end result will be max_stack entries if we have at least that many entries in a given stack trace. Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/n/tip-s8teto51tdqvlfhefndtat9r@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-05-17perf core: Pass max stack as a perf_callchain_entry contextArnaldo Carvalho de Melo
This makes perf_callchain_{user,kernel}() receive the max stack as context for the perf_callchain_entry, instead of accessing the global sysctl_perf_event_max_stack. Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Brendan Gregg <brendan.d.gregg@gmail.com> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: He Kuang <hekuang@huawei.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Milian Wolff <milian.wolff@kdab.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: Wang Nan <wangnan0@huawei.com> Cc: Zefan Li <lizefan@huawei.com> Link: http://lkml.kernel.org/n/tip-kolmn1yo40p7jhswxwrc7rrd@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-05-17perf core: Generalize max_stack sysctl handlerArnaldo Carvalho de Melo
So that it can be used for other stack related knobs, such as the upcoming one to tweak the max number of of contexts per stack sample. In all those cases we can only change the value if there are no perf sessions collecting stacks, so they need to grab that mutex, etc. Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/n/tip-8t3fk94wuzp8m2z1n4gc0s17@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-05-15Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
The nf_conntrack_core.c fix in 'net' is not relevant in 'net-next' because we no longer have a per-netns conntrack hash. The ip_gre.c conflict as well as the iwlwifi ones were cases of overlapping changes. Conflicts: drivers/net/wireless/intel/iwlwifi/mvm/tx.c net/ipv4/ip_gre.c net/netfilter/nf_conntrack_core.c Signed-off-by: David S. Miller <davem@davemloft.net>
2016-05-12perf/core: Disable the event on a truncated AUX recordAlexander Shishkin
When the PMU driver reports a truncated AUX record, it effectively means that there is no more usable room in the event's AUX buffer (even though there may still be some room, so that perf_aux_output_begin() doesn't take action). At this point the consumer still has to be woken up and the event has to be disabled, otherwise the event will just keep spinning between perf_aux_output_begin() and perf_aux_output_end() until its context gets unscheduled. Again, for cpu-wide events this means never, so once in this condition, they will be forever losing data. Fix this by disabling the event and waking up the consumer in case of a truncated AUX record. Reported-by: Markus Metzger <markus.t.metzger@intel.com> Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: <stable@vger.kernel.org> Cc: Arnaldo Carvalho de Melo <acme@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: vince@deater.net Link: http://lkml.kernel.org/r/1462886313-13660-3-git-send-email-alexander.shishkin@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-05-12perf/core: Disable the event on a truncated AUX recordAlexander Shishkin
When the PMU driver reports a truncated AUX record, it effectively means that there is no more usable room in the event's AUX buffer (even though there may still be some room, so that perf_aux_output_begin() doesn't take action). At this point the consumer still has to be woken up and the event has to be disabled, otherwise the event will just keep spinning between perf_aux_output_begin() and perf_aux_output_end() until its context gets unscheduled. Again, for cpu-wide events this means never, so once in this condition, they will be forever losing data. Fix this by disabling the event and waking up the consumer in case of a truncated AUX record. Reported-by: Markus Metzger <markus.t.metzger@intel.com> Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: vince@deater.net Link: http://lkml.kernel.org/r/1462886313-13660-3-git-send-email-alexander.shishkin@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-05-11Merge branch 'perf/urgent' into perf/core, to pick up fixesIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-05-10perf/core: Change the default paranoia level to 2Andy Lutomirski
Allowing unprivileged kernel profiling lets any user dump follow kernel control flow and dump kernel registers. This most likely allows trivial kASLR bypassing, and it may allow other mischief as well. (Off the top of my head, the PERF_SAMPLE_REGS_INTR output during /dev/urandom reads could be quite interesting.) Signed-off-by: Andy Lutomirski <luto@kernel.org> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-05perf/arm: Special-case hetereogeneous CPUsMark Rutland
Commit: 26657848502b7847 ("perf/core: Verify we have a single perf_hw_context PMU") forcefully prevents multiple PMUs from sharing perf_hw_context, as this generally doesn't make sense. It is a common bug for uncore PMUs to use perf_hw_context rather than perf_invalid_context, which this detects. However, systems exist with heterogeneous CPUs (and hence heterogeneous HW PMUs), for which sharing perf_hw_context is necessary, and possible in some limited cases. To make this work we have to perform some gymnastics, as we did in these commits: 66eb579e66ecfea5 ("perf: allow for PMU-specific event filtering") c904e32a69b7c779 ("arm: perf: filter unschedulable events") To allow those systems to work, we must allow PMUs for heterogeneous CPUs to share perf_hw_context, though we must still disallow sharing otherwise to detect the common misuse of perf_hw_context. This patch adds a new PERF_PMU_CAP_HETEROGENEOUS_CPUS for this, updates the core logic to account for this, and makes use of it in the arm_pmu code that is used for systems with heterogeneous CPUs. Comments are added to make the rationale clear and hopefully avoid accidental abuse. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: Will Deacon <will.deacon@arm.com> Cc: linux-arm-kernel@lists.infradead.org Link: http://lkml.kernel.org/r/20160426103346.GA20836@leverpostej Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-05-05perf/core: Let userspace know if the PMU supports address filtersAlexander Shishkin
Export an additional common attribute for PMUs that support address range filtering to let the perf userspace identify such PMUs in a uniform way. Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mathieu Poirier <mathieu.poirier@linaro.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: vince@deater.net Link: http://lkml.kernel.org/r/1461771888-10409-8-git-send-email-alexander.shishkin@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-05-05perf/core: Introduce address range filteringAlexander Shishkin
Many instruction tracing PMUs out there support address range-based filtering, which would, for example, generate trace data only for a given range of instruction addresses, which is useful for tracing individual functions, modules or libraries. Other PMUs may also utilize this functionality to allow filtering to or filtering out code at certain address ranges. This patch introduces the interface for userspace to specify these filters and for the PMU drivers to apply these filters to hardware configuration. The user interface is an ASCII string that is passed via an ioctl() and specifies (in the form of an ASCII string) address ranges within certain object files or within kernel. There is no special treatment for kernel modules yet, but it might be a worthy pursuit. The PMU driver interface basically adds two extra callbacks to the PMU driver structure, one of which validates the filter configuration proposed by the user against what the hardware is actually capable of doing and the other one translates hardware-independent filter configuration into something that can be programmed into the hardware. Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org> Cc: Arnaldo Carvalho de Melo <acme@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: vince@deater.net Link: http://lkml.kernel.org/r/1461771888-10409-6-git-send-email-alexander.shishkin@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-05-05perf/core: Extend perf_event_aux_ctx() to optionally iterate through more eventsAlexander Shishkin
Trace filtering code needs an iterator that can go through all events in a context, including inactive and filtered, to be able to update their filters' address ranges based on mmap or exec events. This patch changes perf_event_aux_ctx() to optionally do this. Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mathieu Poirier <mathieu.poirier@linaro.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: vince@deater.net Link: http://lkml.kernel.org/r/1461771888-10409-5-git-send-email-alexander.shishkin@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-05-05perf/core: Move set_filter() out of CONFIG_EVENT_TRACINGAlexander Shishkin
For instruction trace filtering, namely, for communicating filter definitions from userspace, I'd like to re-use the SET_FILTER code that the tracepoints are using currently. To that end, move the relevant code out from behind the CONFIG_EVENT_TRACING dependency. Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mathieu Poirier <mathieu.poirier@linaro.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: vince@deater.net Link: http://lkml.kernel.org/r/1461771888-10409-2-git-send-email-alexander.shishkin@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>