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2019-06-29Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds1-5/+5
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Ingo Molnar: "Misc fixes all over the place: - might_sleep() atomicity fix in the microcode loader - resctrl boundary condition fix - APIC arithmethics bug fix for frequencies >= 4.2 GHz - three 5-level paging crash fixes - two speculation fixes - a perf/stacktrace fix" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/unwind/orc: Fall back to using frame pointers for generated code perf/x86: Always store regs->ip in perf_callchain_kernel() x86/speculation: Allow guests to use SSBD even if host does not x86/mm: Handle physical-virtual alignment mismatch in phys_p4d_init() x86/boot/64: Add missing fixup_pointer() for next_early_pgt access x86/boot/64: Fix crash if kernel image crosses page table boundary x86/apic: Fix integer overflow on 10 bit left shift of cpu_khz x86/resctrl: Prevent possible overrun during bitmap operations x86/microcode: Fix the microcode load on CPU hotplug for real
2019-06-29Merge branch 'perf-urgent-for-linus' of ↵Linus Torvalds3-28/+8
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf fixes from Ingo Molnar: "Various fixes, most of them related to bugs perf fuzzing found in the x86 code" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf/x86/regs: Use PERF_REG_EXTENDED_MASK perf/x86: Remove pmu->pebs_no_xmm_regs perf/x86: Clean up PEBS_XMM_REGS perf/x86/regs: Check reserved bits perf/x86: Disable extended registers for non-supported PMUs perf/ioctl: Add check for the sample_period value perf/core: Fix perf_sample_regs_user() mm check
2019-06-28perf/x86: Always store regs->ip in perf_callchain_kernel()Song Liu1-5/+5
The stacktrace_map_raw_tp BPF selftest is failing because the RIP saved by perf_arch_fetch_caller_regs() isn't getting saved by perf_callchain_kernel(). This was broken by the following commit: d15d356887e7 ("perf/x86: Make perf callchains work without CONFIG_FRAME_POINTER") With that change, when starting with non-HW regs, the unwinder starts with the current stack frame and unwinds until it passes up the frame which called perf_arch_fetch_caller_regs(). So regs->ip needs to be saved deliberately. Fixes: d15d356887e7 ("perf/x86: Make perf callchains work without CONFIG_FRAME_POINTER") Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Kairui Song <kasong@redhat.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Borislav Petkov <bp@alien8.de> Link: https://lkml.kernel.org/r/3975a298fa52b506fea32666d8ff6a13467eee6d.1561595111.git.jpoimboe@redhat.com
2019-06-24perf/x86: Remove pmu->pebs_no_xmm_regsKan Liang3-7/+4
We don't need pmu->pebs_no_xmm_regs anymore, the capabilities PERF_PMU_CAP_EXTENDED_REGS can be used to check if XMM registers collection is supported. Signed-off-by: Kan Liang <kan.liang@linux.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: https://lkml.kernel.org/r/1559081314-9714-4-git-send-email-kan.liang@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-24perf/x86: Clean up PEBS_XMM_REGSKan Liang3-21/+3
Use generic macro PERF_REG_EXTENDED_MASK to replace PEBS_XMM_REGS to avoid duplication. Signed-off-by: Kan Liang <kan.liang@linux.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: https://lkml.kernel.org/r/1559081314-9714-3-git-send-email-kan.liang@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-24perf/x86: Disable extended registers for non-supported PMUsKan Liang1-0/+1
The perf fuzzer caused Skylake machine to crash: [ 9680.085831] Call Trace: [ 9680.088301] <IRQ> [ 9680.090363] perf_output_sample_regs+0x43/0xa0 [ 9680.094928] perf_output_sample+0x3aa/0x7a0 [ 9680.099181] perf_event_output_forward+0x53/0x80 [ 9680.103917] __perf_event_overflow+0x52/0xf0 [ 9680.108266] ? perf_trace_run_bpf_submit+0xc0/0xc0 [ 9680.113108] perf_swevent_hrtimer+0xe2/0x150 [ 9680.117475] ? check_preempt_wakeup+0x181/0x230 [ 9680.122091] ? check_preempt_curr+0x62/0x90 [ 9680.126361] ? ttwu_do_wakeup+0x19/0x140 [ 9680.130355] ? try_to_wake_up+0x54/0x460 [ 9680.134366] ? reweight_entity+0x15b/0x1a0 [ 9680.138559] ? __queue_work+0x103/0x3f0 [ 9680.142472] ? update_dl_rq_load_avg+0x1cd/0x270 [ 9680.147194] ? timerqueue_del+0x1e/0x40 [ 9680.151092] ? __remove_hrtimer+0x35/0x70 [ 9680.155191] __hrtimer_run_queues+0x100/0x280 [ 9680.159658] hrtimer_interrupt+0x100/0x220 [ 9680.163835] smp_apic_timer_interrupt+0x6a/0x140 [ 9680.168555] apic_timer_interrupt+0xf/0x20 [ 9680.172756] </IRQ> The XMM registers can only be collected by PEBS hardware events on the platforms with PEBS baseline support, e.g. Icelake, not software/probe events. Add capabilities flag PERF_PMU_CAP_EXTENDED_REGS to indicate the PMU which support extended registers. For X86, the extended registers are XMM registers. Add has_extended_regs() to check if extended registers are applied. The generic code define the mask of extended registers as 0 if arch headers haven't overridden it. Originally-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reported-by: Vince Weaver <vincent.weaver@maine.edu> Signed-off-by: Kan Liang <kan.liang@linux.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> Fixes: 878068ea270e ("perf/x86: Support outputting XMM registers") Link: https://lkml.kernel.org/r/1559081314-9714-1-git-send-email-kan.liang@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-19treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500Thomas Gleixner4-16/+4
Based on 2 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation # extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 4122 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Enrico Weigelt <info@metux.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-05treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 288Thomas Gleixner3-27/+3
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms and conditions of the gnu general public license version 2 as published by the free software foundation this program is distributed in the hope it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 263 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Alexios Zavras <alexios.zavras@intel.com> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190529141901.208660670@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-02Merge branch 'perf-urgent-for-linus' of ↵Linus Torvalds1-14/+14
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf fixes from Ingo Molnar: "On the kernel side there's a bunch of ring-buffer ordering fixes for a reproducible bug, plus a PEBS constraints regression fix. Plus tooling fixes" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: tools headers UAPI: Sync kvm.h headers with the kernel sources perf record: Fix s390 missing module symbol and warning for non-root users perf machine: Read also the end of the kernel perf test vmlinux-kallsyms: Ignore aliases to _etext when searching on kallsyms perf session: Add missing swap ops for namespace events perf namespace: Protect reading thread's namespace tools headers UAPI: Sync drm/drm.h with the kernel tools headers UAPI: Sync drm/i915_drm.h with the kernel tools headers UAPI: Sync linux/fs.h with the kernel tools headers UAPI: Sync linux/sched.h with the kernel tools arch x86: Sync asm/cpufeatures.h with the with the kernel tools include UAPI: Update copy of files related to new fspick, fsmount, fsconfig, fsopen, move_mount and open_tree syscalls perf arm64: Fix mksyscalltbl when system kernel headers are ahead of the kernel perf data: Fix 'strncat may truncate' build failure with recent gcc perf/ring-buffer: Use regular variables for nesting perf/ring-buffer: Always use {READ,WRITE}_ONCE() for rb->user_page data perf/ring_buffer: Add ordering to rb->nest increment perf/ring_buffer: Fix exposing a temporarily decreased data_head perf/x86/intel/ds: Fix EVENT vs. UEVENT PEBS constraints
2019-05-21treewide: Add SPDX license identifier - Makefile/KconfigThomas Gleixner1-0/+1
Add SPDX license identifiers to all Make/Kconfig files which: - Have no license information of any form These files fall under the project license, GPL v2 only. The resulting SPDX license identifier is: GPL-2.0-only Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21treewide: Add SPDX license identifier for more missed filesThomas Gleixner2-0/+2
Add SPDX license identifiers to all files which: - Have no license information of any form - Have MODULE_LICENCE("GPL*") inside which was used in the initial scan/conversion to ignore the file These files fall under the project license, GPL v2 only. The resulting SPDX license identifier is: GPL-2.0-only Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21treewide: Add SPDX license identifier for missed filesThomas Gleixner2-0/+2
Add SPDX license identifiers to all files which: - Have no license information of any form - Have EXPORT_.*_SYMBOL_GPL inside which was used in the initial scan/conversion to ignore the file These files fall under the project license, GPL v2 only. The resulting SPDX license identifier is: GPL-2.0-only Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21perf/x86/intel/ds: Fix EVENT vs. UEVENT PEBS constraintsStephane Eranian1-14/+14
This patch fixes an bug revealed by the following commit: 6b89d4c1ae85 ("perf/x86/intel: Fix INTEL_FLAGS_EVENT_CONSTRAINT* masking") That patch modified INTEL_FLAGS_EVENT_CONSTRAINT() to only look at the event code when matching a constraint. If code+umask were needed, then the INTEL_FLAGS_UEVENT_CONSTRAINT() macro was needed instead. This broke with some of the constraints for PEBS events. Several of them, including the one used for cycles:p, cycles:pp, cycles:ppp fell in that category and caused the event to be rejected in PEBS mode. In other words, on some platforms a cmdline such as: $ perf top -e cycles:pp would fail with -EINVAL. This patch fixes this bug by properly using INTEL_FLAGS_UEVENT_CONSTRAINT() when needed in the PEBS constraint tables. Reported-by: Ingo Molnar <mingo@kernel.org> Signed-off-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: 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> Cc: kan.liang@intel.com Link: http://lkml.kernel.org/r/20190521005246.423-1-eranian@google.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-05-17Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds1-1/+5
Pull KVM updates from Paolo Bonzini: "ARM: - support for SVE and Pointer Authentication in guests - PMU improvements POWER: - support for direct access to the POWER9 XIVE interrupt controller - memory and performance optimizations x86: - support for accessing memory not backed by struct page - fixes and refactoring Generic: - dirty page tracking improvements" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (155 commits) kvm: fix compilation on aarch64 Revert "KVM: nVMX: Expose RDPMC-exiting only when guest supports PMU" kvm: x86: Fix L1TF mitigation for shadow MMU KVM: nVMX: Disable intercept for FS/GS base MSRs in vmcs02 when possible KVM: PPC: Book3S: Remove useless checks in 'release' method of KVM device KVM: PPC: Book3S HV: XIVE: Fix spelling mistake "acessing" -> "accessing" KVM: PPC: Book3S HV: Make sure to load LPID for radix VCPUs kvm: nVMX: Set nested_run_pending in vmx_set_nested_state after checks complete tests: kvm: Add tests for KVM_SET_NESTED_STATE KVM: nVMX: KVM_SET_NESTED_STATE - Tear down old EVMCS state before setting new state tests: kvm: Add tests for KVM_CAP_MAX_VCPUS and KVM_CAP_MAX_CPU_ID tests: kvm: Add tests to .gitignore KVM: Introduce KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2 KVM: Fix kvm_clear_dirty_log_protect off-by-(minus-)one KVM: Fix the bitmap range to copy during clear dirty KVM: arm64: Fix ptrauth ID register masking logic KVM: x86: use direct accessors for RIP and RSP KVM: VMX: Use accessors for GPRs outside of dedicated caching logic KVM: x86: Omit caching logic for always-available GPRs kvm, x86: Properly check whether a pfn is an MMIO or not ...
2019-05-16Merge branch 'perf-urgent-for-linus' of ↵Linus Torvalds3-4/+4
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf fixes from Ingo Molnar: "An x86 PMU constraint fix, an interface fix, and a Sparse fix" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf/x86/intel: Allow PEBS multi-entry in watermark mode perf/x86/intel: Fix INTEL_FLAGS_EVENT_CONSTRAINT* masking perf/x86/amd/iommu: Make the 'amd_iommu_attr_groups' symbol static
2019-05-14treewide: replace #include <asm/sizes.h> with #include <linux/sizes.h>Masahiro Yamada1-1/+1
Since commit dccd2304cc90 ("ARM: 7430/1: sizes.h: move from asm-generic to <linux/sizes.h>"), <asm/sizes.h> and <asm-generic/sizes.h> are just wrappers of <linux/sizes.h>. This commit replaces all <asm/sizes.h> and <asm-generic/sizes.h> to prepare for the removal. Link: http://lkml.kernel.org/r/1553267665-27228-1-git-send-email-yamada.masahiro@socionext.com Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14perf/x86/intel: Allow PEBS multi-entry in watermark modeStephane Eranian1-1/+1
This patch fixes a restriction/bug introduced by: 583feb08e7f7 ("perf/x86/intel: Fix handling of wakeup_events for multi-entry PEBS") The original patch prevented using multi-entry PEBS when wakeup_events != 0. However given that wakeup_events is part of a union with wakeup_watermark, it means that in watermark mode, PEBS multi-entry is also disabled which is not the intent. This patch fixes this by checking is watermark mode is enabled. Signed-off-by: Stephane Eranian <eranian@google.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: jolsa@redhat.com Cc: kan.liang@intel.com Cc: vincent.weaver@maine.edu Fixes: 583feb08e7f7 ("perf/x86/intel: Fix handling of wakeup_events for multi-entry PEBS") Link: http://lkml.kernel.org/r/20190514003400.224340-1-eranian@google.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-05-10perf/x86/intel: Fix INTEL_FLAGS_EVENT_CONSTRAINT* maskingStephane Eranian1-2/+2
On Intel Westmere, a cmdline as follows: $ perf record -e cpu/event=0xc4,umask=0x2,name=br_inst_retired.near_call/p .... was failing. Yet the event+ umask support PEBS. It turns out this is due to a bug in the the PEBS event constraint table for westmere. All forms of BR_INST_RETIRED.* support PEBS. Therefore the constraint mask should ignore the umask. The name of the macro INTEL_FLAGS_EVENT_CONSTRAINT() hint that this is the case but it was not. That macros was checking both the event code and event umask. Therefore, it was only matching on 0x00c4. There are code+umask macros, they all have *UEVENT*. This bug fixes the issue by checking only the event code in the mask. Both single and range version are modified. Signed-off-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: 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> Cc: kan.liang@intel.com Link: http://lkml.kernel.org/r/20190509214556.123493-1-eranian@google.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-05-08perf/x86/amd/iommu: Make the 'amd_iommu_attr_groups' symbol staticWang Hai1-1/+1
Fixes the following sparse warning: arch/x86/events/amd/iommu.c:396:30: warning: symbol 'amd_iommu_attr_groups' was not declared. Should it be static? Signed-off-by: Wang Hai <wanghai26@huawei.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: acme@kernel.org Cc: alexander.shishkin@linux.intel.com Cc: bp@alien8.de Cc: jolsa@redhat.com Cc: namhyung@kernel.org Fixes: 51686546304f (x86/events/amd/iommu: Fix sysfs perf attribute groups) Link: http://lkml.kernel.org/r/20190508020418.19568-1-wanghai26@huawei.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-05-06Merge branch 'perf-core-for-linus' of ↵Linus Torvalds11-132/+1000
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf updates from Ingo Molnar: "The main kernel changes were: - add support for Intel's "adaptive PEBS v4" - which embedds LBS data in PEBS records and can thus batch up and reduce the IRQ (NMI) rate significantly - reducing overhead and making call-graph profiling less intrusive. - add Intel CPU core and uncore support updates for Tremont, Icelake, - extend the x86 PMU constraints scheduler with 'constraint ranges' to better support Icelake hw constraints, - make x86 call-chain support work better with CONFIG_FRAME_POINTER=y - misc other changes Tooling changes: - updates to the main tools: 'perf record', 'perf trace', 'perf stat' - updated Intel and S/390 vendor events - libtraceevent updates - misc other updates and fixes" * 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (69 commits) perf/x86: Make perf callchains work without CONFIG_FRAME_POINTER watchdog: Fix typo in comment perf/x86/intel: Add Tremont core PMU support perf/x86/intel/uncore: Add Intel Icelake uncore support perf/x86/msr: Add Icelake support perf/x86/intel/rapl: Add Icelake support perf/x86/intel/cstate: Add Icelake support perf/x86/intel: Add Icelake support perf/x86: Support constraint ranges perf/x86/lbr: Avoid reading the LBRs when adaptive PEBS handles them perf/x86/intel: Support adaptive PEBS v4 perf/x86/intel/ds: Extract code of event update in short period perf/x86/intel: Extract memory code PEBS parser for reuse perf/x86: Support outputting XMM registers perf/x86/intel: Force resched when TFA sysctl is modified perf/core: Add perf_pmu_resched() as global function perf/headers: Fix stale comment for struct perf_addr_filter perf/core: Make perf_swevent_init_cpu() static perf/x86: Add sanity checks to x86_schedule_events() perf/x86: Optimize x86_schedule_events() ...
2019-05-05perf/x86/intel: Fix race in intel_pmu_disable_event()Jiri Olsa1-3/+7
New race in x86_pmu_stop() was introduced by replacing the atomic __test_and_clear_bit() of cpuc->active_mask by separate test_bit() and __clear_bit() calls in the following commit: 3966c3feca3f ("x86/perf/amd: Remove need to check "running" bit in NMI handler") The race causes panic for PEBS events with enabled callchains: BUG: unable to handle kernel NULL pointer dereference at 0000000000000000 ... RIP: 0010:perf_prepare_sample+0x8c/0x530 Call Trace: <NMI> perf_event_output_forward+0x2a/0x80 __perf_event_overflow+0x51/0xe0 handle_pmi_common+0x19e/0x240 intel_pmu_handle_irq+0xad/0x170 perf_event_nmi_handler+0x2e/0x50 nmi_handle+0x69/0x110 default_do_nmi+0x3e/0x100 do_nmi+0x11a/0x180 end_repeat_nmi+0x16/0x1a RIP: 0010:native_write_msr+0x6/0x20 ... </NMI> intel_pmu_disable_event+0x98/0xf0 x86_pmu_stop+0x6e/0xb0 x86_pmu_del+0x46/0x140 event_sched_out.isra.97+0x7e/0x160 ... The event is configured to make samples from PEBS drain code, but when it's disabled, we'll go through NMI path instead, where data->callchain will not get allocated and we'll crash: x86_pmu_stop test_bit(hwc->idx, cpuc->active_mask) intel_pmu_disable_event(event) { ... intel_pmu_pebs_disable(event); ... EVENT OVERFLOW -> <NMI> intel_pmu_handle_irq handle_pmi_common TEST PASSES -> test_bit(bit, cpuc->active_mask)) perf_event_overflow perf_prepare_sample { ... if (!(sample_type & __PERF_SAMPLE_CALLCHAIN_EARLY)) data->callchain = perf_callchain(event, regs); CRASH -> size += data->callchain->nr; } </NMI> ... x86_pmu_disable_event(event) } __clear_bit(hwc->idx, cpuc->active_mask); Fixing this by disabling the event itself before setting off the PEBS bit. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: David Arcari <darcari@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Lendacky Thomas <Thomas.Lendacky@amd.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> Fixes: 3966c3feca3f ("x86/perf/amd: Remove need to check "running" bit in NMI handler") Link: http://lkml.kernel.org/r/20190504151556.31031-1-jolsa@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-05-03perf/x86/intel/pt: Remove software double buffering PMU capabilityAlexander Shishkin1-2/+1
Now that all AUX allocations are high-order by default, the software double buffering PMU capability doesn't make sense any more, get rid of it. In case some PMUs choose to opt out, we can re-introduce it. Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: adrian.hunter@intel.com Link: http://lkml.kernel.org/r/20190503085536.24119-3-alexander.shishkin@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-05-02perf/x86/amd: Update generic hardware cache events for Family 17hKim Phillips1-3/+108
Add a new amd_hw_cache_event_ids_f17h assignment structure set for AMD families 17h and above, since a lot has changed. Specifically: L1 Data Cache The data cache access counter remains the same on Family 17h. For DC misses, PMCx041's definition changes with Family 17h, so instead we use the L2 cache accesses from L1 data cache misses counter (PMCx060,umask=0xc8). For DC hardware prefetch events, Family 17h breaks compatibility for PMCx067 "Data Prefetcher", so instead, we use PMCx05a "Hardware Prefetch DC Fills." L1 Instruction Cache PMCs 0x80 and 0x81 (32-byte IC fetches and misses) are backward compatible on Family 17h. For prefetches, we remove the erroneous PMCx04B assignment which counts how many software data cache prefetch load instructions were dispatched. LL - Last Level Cache Removing PMCs 7D, 7E, and 7F assignments, as they do not exist on Family 17h, where the last level cache is L3. L3 counters can be accessed using the existing AMD Uncore driver. Data TLB On Intel machines, data TLB accesses ("dTLB-loads") are assigned to counters that count load/store instructions retired. This is inconsistent with instruction TLB accesses, where Intel implementations report iTLB misses that hit in the STLB. Ideally, dTLB-loads would count higher level dTLB misses that hit in lower level TLBs, and dTLB-load-misses would report those that also missed in those lower-level TLBs, therefore causing a page table walk. That would be consistent with instruction TLB operation, remove the redundancy between dTLB-loads and L1-dcache-loads, and prevent perf from producing artificially low percentage ratios, i.e. the "0.01%" below: 42,550,869 L1-dcache-loads 41,591,860 dTLB-loads 4,802 dTLB-load-misses # 0.01% of all dTLB cache hits 7,283,682 L1-dcache-stores 7,912,392 dTLB-stores 310 dTLB-store-misses On AMD Families prior to 17h, the "Data Cache Accesses" counter is used, which is slightly better than load/store instructions retired, but still counts in terms of individual load/store operations instead of TLB operations. So, for AMD Families 17h and higher, this patch assigns "dTLB-loads" to a counter for L1 dTLB misses that hit in the L2 dTLB, and "dTLB-load-misses" to a counter for L1 DTLB misses that caused L2 DTLB misses and therefore also caused page table walks. This results in a much more accurate view of data TLB performance: 60,961,781 L1-dcache-loads 4,601 dTLB-loads 963 dTLB-load-misses # 20.93% of all dTLB cache hits Note that for all AMD families, data loads and stores are combined in a single accesses counter, so no 'L1-dcache-stores' are reported separately, and stores are counted with loads in 'L1-dcache-loads'. Also note that the "% of all dTLB cache hits" string is misleading because (a) "dTLB cache": although TLBs can be considered caches for page tables, in this context, it can be misinterpreted as data cache hits because the figures are similar (at least on Intel), and (b) not all those loads (technically accesses) technically "hit" at that hardware level. "% of all dTLB accesses" would be more clear/accurate. Instruction TLB On Intel machines, 'iTLB-loads' measure iTLB misses that hit in the STLB, and 'iTLB-load-misses' measure iTLB misses that also missed in the STLB and completed a page table walk. For AMD Family 17h and above, for 'iTLB-loads' we replace the erroneous instruction cache fetches counter with PMCx084 "L1 ITLB Miss, L2 ITLB Hit". For 'iTLB-load-misses' we still use PMCx085 "L1 ITLB Miss, L2 ITLB Miss", but set a 0xff umask because without it the event does not get counted. Branch Predictor (BPU) PMCs 0xc2 and 0xc3 continue to be valid across all AMD Families. Node Level Events Family 17h does not have a PMCx0e9 counter, and corresponding counters have not been made available publicly, so for now, we mark them as unsupported for Families 17h and above. Reference: "Open-Source Register Reference For AMD Family 17h Processors Models 00h-2Fh" Released 7/17/2018, Publication #56255, Revision 3.03: https://www.amd.com/system/files/TechDocs/56255_OSRR.pdf [ mingo: tidied up the line breaks. ] Signed-off-by: Kim Phillips <kim.phillips@amd.com> Cc: <stable@vger.kernel.org> # v4.9+ Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Janakarajan Natarajan <Janakarajan.Natarajan@amd.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Martin Liška <mliska@suse.cz> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Pu Wen <puwen@hygon.cn> Cc: Stephane Eranian <eranian@google.com> Cc: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Thomas Lendacky <Thomas.Lendacky@amd.com> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: linux-kernel@vger.kernel.org Cc: linux-perf-users@vger.kernel.org Fixes: e40ed1542dd7 ("perf/x86: Add perf support for AMD family-17h processors") Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-30KVM: x86: Inject PMI for KVM guestLuwei Kang1-1/+5
Inject a PMI for KVM guest when Intel PT working in Host-Guest mode and Guest ToPA entry memory buffer was completely filled. Signed-off-by: Luwei Kang <luwei.kang@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-04-29perf/x86: Make perf callchains work without CONFIG_FRAME_POINTERKairui Song1-4/+17
Currently perf callchain doesn't work well with ORC unwinder when sampling from trace point. We'll get useless in kernel callchain like this: perf 6429 [000] 22.498450: kmem:mm_page_alloc: page=0x176a17 pfn=1534487 order=0 migratetype=0 gfp_flags=GFP_KERNEL ffffffffbe23e32e __alloc_pages_nodemask+0x22e (/lib/modules/5.1.0-rc3+/build/vmlinux) 7efdf7f7d3e8 __poll+0x18 (/usr/lib64/libc-2.28.so) 5651468729c1 [unknown] (/usr/bin/perf) 5651467ee82a main+0x69a (/usr/bin/perf) 7efdf7eaf413 __libc_start_main+0xf3 (/usr/lib64/libc-2.28.so) 5541f689495641d7 [unknown] ([unknown]) The root cause is that, for trace point events, it doesn't provide a real snapshot of the hardware registers. Instead perf tries to get required caller's registers and compose a fake register snapshot which suppose to contain enough information for start a unwinding. However without CONFIG_FRAME_POINTER, if failed to get caller's BP as the frame pointer, so current frame pointer is returned instead. We get a invalid register combination which confuse the unwinder, and end the stacktrace early. So in such case just don't try dump BP, and let the unwinder start directly when the register is not a real snapshot. Use SP as the skip mark, unwinder will skip all the frames until it meet the frame of the trace point caller. Tested with frame pointer unwinder and ORC unwinder, this makes perf callchain get the full kernel space stacktrace again like this: perf 6503 [000] 1567.570191: kmem:mm_page_alloc: page=0x16c904 pfn=1493252 order=0 migratetype=0 gfp_flags=GFP_KERNEL ffffffffb523e2ae __alloc_pages_nodemask+0x22e (/lib/modules/5.1.0-rc3+/build/vmlinux) ffffffffb52383bd __get_free_pages+0xd (/lib/modules/5.1.0-rc3+/build/vmlinux) ffffffffb52fd28a __pollwait+0x8a (/lib/modules/5.1.0-rc3+/build/vmlinux) ffffffffb521426f perf_poll+0x2f (/lib/modules/5.1.0-rc3+/build/vmlinux) ffffffffb52fe3e2 do_sys_poll+0x252 (/lib/modules/5.1.0-rc3+/build/vmlinux) ffffffffb52ff027 __x64_sys_poll+0x37 (/lib/modules/5.1.0-rc3+/build/vmlinux) ffffffffb500418b do_syscall_64+0x5b (/lib/modules/5.1.0-rc3+/build/vmlinux) ffffffffb5a0008c entry_SYSCALL_64_after_hwframe+0x44 (/lib/modules/5.1.0-rc3+/build/vmlinux) 7f71e92d03e8 __poll+0x18 (/usr/lib64/libc-2.28.so) 55a22960d9c1 [unknown] (/usr/bin/perf) 55a22958982a main+0x69a (/usr/bin/perf) 7f71e9202413 __libc_start_main+0xf3 (/usr/lib64/libc-2.28.so) 5541f689495641d7 [unknown] ([unknown]) Co-developed-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Kairui Song <kasong@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.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: Borislav Petkov <bp@alien8.de> Cc: Dave Young <dyoung@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20190422162652.15483-1-kasong@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-25perf/x86/intel: Update KBL Package C-state events to also include ↵Harry Pan1-5/+5
PC8/PC9/PC10 counters Kaby Lake (and Coffee Lake) has PC8/PC9/PC10 residency counters. This patch updates the list of Kaby/Coffee Lake PMU event counters from the snb_cstates[] list of events to the hswult_cstates[] list of events, which keeps all previously supported events and also adds the PKG_C8, PKG_C9 and PKG_C10 residency counters. This allows user space tools to profile them through the perf interface. Signed-off-by: Harry Pan <harry.pan@intel.com> Cc: <stable@vger.kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> 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: gs0622@gmail.com Link: http://lkml.kernel.org/r/20190424145033.1924-1-harry.pan@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-18perf/x86/amd: Add event map for AMD Family 17hKim Phillips1-9/+26
Family 17h differs from prior families by: - Does not support an L2 cache miss event - It has re-enumerated PMC counters for: - L2 cache references - front & back end stalled cycles So we add a new amd_f17h_perfmon_event_map[] so that the generic perf event names will resolve to the correct h/w events on family 17h and above processors. Reference sections 2.1.13.3.3 (stalls) and 2.1.13.3.6 (L2): https://www.amd.com/system/files/TechDocs/54945_PPR_Family_17h_Models_00h-0Fh.pdf Signed-off-by: Kim Phillips <kim.phillips@amd.com> Cc: <stable@vger.kernel.org> # v4.9+ Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Janakarajan Natarajan <Janakarajan.Natarajan@amd.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Martin Liška <mliska@suse.cz> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Pu Wen <puwen@hygon.cn> Cc: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Fixes: e40ed1542dd7 ("perf/x86: Add perf support for AMD family-17h processors") [ Improved the formatting a bit. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-16perf/x86/intel: Add Tremont core PMU supportKan Liang1-0/+91
Add perf core PMU support for Intel Tremont CPU. The init code is based on Goldmont plus. The generic purpose counter 0 and fixed counter 0 have less skid. Force :ppp events on generic purpose counter 0. Force instruction:ppp on generic purpose counter 0 and fixed counter 0. Updates LLC cache event table and OFFCORE_RESPONSE mask. Adaptive PEBS, which is already enabled on ICL, is also supported on Tremont. No extra code required. Signed-off-by: Kan Liang <kan.liang@linux.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 Cc: jolsa@kernel.org Link: https://lkml.kernel.org/r/1554922629-126287-3-git-send-email-kan.liang@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-16perf/x86/intel/uncore: Add Intel Icelake uncore supportKan Liang3-0/+98
Add Intel Icelake uncore support: - The init code is based on Skylake - Add new PCI id for IMC - New MSR address for CBOX - Get CBOX# from CNL_UNC_CBO_CONFIG MSR directly - Create a new PMU for fixed clocktick counter Signed-off-by: Kan Liang <kan.liang@linux.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 Cc: jolsa@kernel.org Link: https://lkml.kernel.org/r/20190402194509.2832-13-kan.liang@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-16perf/x86/msr: Add Icelake supportKan Liang1-0/+1
Icelake is the same as the existing Skylake parts. Signed-off-by: Kan Liang <kan.liang@linux.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 Cc: jolsa@kernel.org Link: https://lkml.kernel.org/r/20190402194509.2832-12-kan.liang@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-16perf/x86/intel/rapl: Add Icelake supportKan Liang1-0/+2
Icelake support the same RAPL counters as Skylake. Signed-off-by: Kan Liang <kan.liang@linux.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 Cc: jolsa@kernel.org Link: https://lkml.kernel.org/r/20190402194509.2832-11-kan.liang@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-16perf/x86/intel/cstate: Add Icelake supportKan Liang1-0/+2
Icelake uses the same C-state residency events as Sandy Bridge. Signed-off-by: Kan Liang <kan.liang@linux.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 Cc: jolsa@kernel.org Link: https://lkml.kernel.org/r/20190402194509.2832-10-kan.liang@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-16perf/x86/intel: Add Icelake supportKan Liang3-2/+136
Add Icelake core PMU perf code, including constraint tables and the main enable code. Icelake expanded the generic counters to always 8 even with HT on, but a range of events cannot be scheduled on the extra 4 counters. Add new constraint ranges to describe this to the scheduler. The number of constraints that need to be checked is larger now than with earlier CPUs. At some point we may need a new data structure to look them up more efficiently than with linear search. So far it still seems to be acceptable however. Icelake added a new fixed counter SLOTS. Full support for it is added later in the patch series. The cache events table is identical to Skylake. Compare to PEBS instruction event on generic counter, fixed counter 0 has less skid. Force instruction:ppp always in fixed counter 0. Originally-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Kan Liang <kan.liang@linux.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 Cc: jolsa@kernel.org Link: https://lkml.kernel.org/r/20190402194509.2832-9-kan.liang@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-16perf/x86: Support constraint rangesPeter Zijlstra3-8/+39
Icelake extended the general counters to 8, even when SMT is enabled. However only a (large) subset of the events can be used on all 8 counters. The events that can or cannot be used on all counters are organized in ranges. A lot of scheduler constraints are required to handle all this. To avoid blowing up the tables add event code ranges to the constraint tables, and a new inline function to match them. Originally-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> # developer hat on Signed-off-by: Kan Liang <kan.liang@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> # maintainer hat on 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 Cc: jolsa@kernel.org Link: https://lkml.kernel.org/r/20190402194509.2832-8-kan.liang@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-16perf/x86/lbr: Avoid reading the LBRs when adaptive PEBS handles themAndi Kleen2-1/+13
With adaptive PEBS the CPU can directly supply the LBR information, so we don't need to read it again. But the LBRs still need to be enabled. Add a special count to the cpuc that distinguishes these two cases, and avoid reading the LBRs unnecessarily when PEBS is active. Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Kan Liang <kan.liang@linux.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 Cc: jolsa@kernel.org Link: https://lkml.kernel.org/r/20190402194509.2832-7-kan.liang@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-16perf/x86/intel: Support adaptive PEBS v4Kan Liang4-26/+394
Adaptive PEBS is a new way to report PEBS sampling information. Instead of a fixed size record for all PEBS events it allows to configure the PEBS record to only include the information needed. Events can then opt in to use such an extended record, or stay with a basic record which only contains the IP. The major new feature is to support LBRs in PEBS record. Besides normal LBR, this allows (much faster) large PEBS, while still supporting callstacks through callstack LBR. So essentially a lot of profiling can now be done without frequent interrupts, dropping the overhead significantly. The main requirement still is to use a period, and not use frequency mode, because frequency mode requires reevaluating the frequency on each overflow. The floating point state (XMM) is also supported, which allows efficient profiling of FP function arguments. Introduce specific drain function to handle variable length records. Use a new callback to parse the new record format, and also handle the STATUS field now being at a different offset. Add code to set up the configuration register. Since there is only a single register, all events either get the full super set of all events, or only the basic record. Originally-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Kan Liang <kan.liang@linux.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 Cc: jolsa@kernel.org Link: https://lkml.kernel.org/r/20190402194509.2832-6-kan.liang@linux.intel.com [ Renamed GPRS => GP. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-16perf/x86/intel/ds: Extract code of event update in short periodKan Liang1-13/+20
The drain_pebs() could be called twice in a short period for auto-reload event in pmu::read(). The intel_pmu_save_and_restart_reload() should be called to update the event->count. This case should also be handled on Icelake. Extract the code for later reuse. Signed-off-by: Kan Liang <kan.liang@linux.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 Cc: jolsa@kernel.org Link: https://lkml.kernel.org/r/20190402194509.2832-5-kan.liang@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-16perf/x86/intel: Extract memory code PEBS parser for reuseAndi Kleen1-29/+34
Extract some code related to memory profiling from the PEBS record parser into separate functions. It can be reused by the upcoming adaptive PEBS parser. No functional changes. Rename intel_hsw_weight to intel_get_tsx_weight, and intel_hsw_transaction to intel_get_tsx_transaction. Because the input is not the hsw pebs format anymore. Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Kan Liang <kan.liang@linux.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 Cc: jolsa@kernel.org Link: https://lkml.kernel.org/r/20190402194509.2832-4-kan.liang@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-16perf/x86: Support outputting XMM registersKan Liang3-2/+38
Starting from Icelake, XMM registers can be collected in PEBS record. But current code only output the pt_regs. Add a new struct x86_perf_regs for both pt_regs and xmm_regs. The xmm_regs will be used later to keep a pointer to PEBS record which has XMM information. XMM registers are 128 bit. To simplify the code, they are handled like two different registers, which means setting two bits in the register bitmap. This also allows only sampling the lower 64bit bits in XMM. The index of XMM registers starts from 32. There are 16 XMM registers. So all reserved space for regs are used. Remove REG_RESERVED. Add PERF_REG_X86_XMM_MAX, which stands for the max number of all x86 regs including both GPRs and XMM. Add REG_NOSUPPORT for 32bit to exclude unsupported registers. Previous platforms can not collect XMM information in PEBS record. Adding pebs_no_xmm_regs to indicate the unsupported platforms. The common code still validates the supported registers. However, it cannot check model specific registers, e.g. XMM. Add extra check in x86_pmu_hw_config() to reject invalid config of regs_user and regs_intr. The regs_user never supports XMM collection. The regs_intr only supports XMM collection when sampling PEBS event on icelake and later platforms. Originally-by: Andi Kleen <ak@linux.intel.com> Suggested-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Kan Liang <kan.liang@linux.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 Cc: jolsa@kernel.org Link: https://lkml.kernel.org/r/20190402194509.2832-3-kan.liang@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-16perf/x86/intel: Force resched when TFA sysctl is modifiedStephane Eranian3-2/+53
This patch provides guarantee to the sysadmin that when TFA is disabled, no PMU event is using PMC3 when the echo command returns. Vice-Versa, when TFA is enabled, PMU can use PMC3 immediately (to eliminate possible multiplexing). $ perf stat -a -I 1000 --no-merge -e branches,branches,branches,branches 1.000123979 125,768,725,208 branches 1.000562520 125,631,000,456 branches 1.000942898 125,487,114,291 branches 1.001333316 125,323,363,620 branches 2.004721306 125,514,968,546 branches 2.005114560 125,511,110,861 branches 2.005482722 125,510,132,724 branches 2.005851245 125,508,967,086 branches 3.006323475 125,166,570,648 branches 3.006709247 125,165,650,056 branches 3.007086605 125,164,639,142 branches 3.007459298 125,164,402,912 branches 4.007922698 125,045,577,140 branches 4.008310775 125,046,804,324 branches 4.008670814 125,048,265,111 branches 4.009039251 125,048,677,611 branches 5.009503373 125,122,240,217 branches 5.009897067 125,122,450,517 branches Then on another connection, sysadmin does: $ echo 1 >/sys/devices/cpu/allow_tsx_force_abort Then perf stat adjusts the events immediately: 5.010286029 125,121,393,483 branches 5.010646308 125,120,556,786 branches 6.011113588 124,963,351,832 branches 6.011510331 124,964,267,566 branches 6.011889913 124,964,829,130 branches 6.012262996 124,965,841,156 branches 7.012708299 124,419,832,234 branches [79.69%] 7.012847908 124,416,363,853 branches [79.73%] 7.013225462 124,400,723,712 branches [79.73%] 7.013598191 124,376,154,434 branches [79.70%] 8.014089834 124,250,862,693 branches [74.98%] 8.014481363 124,267,539,139 branches [74.94%] 8.014856006 124,259,519,786 branches [74.98%] 8.014980848 124,225,457,969 branches [75.04%] 9.015464576 124,204,235,423 branches [75.03%] 9.015858587 124,204,988,490 branches [75.04%] 9.016243680 124,220,092,486 branches [74.99%] 9.016620104 124,231,260,146 branches [74.94%] And vice-versa if the syadmin does: $ echo 0 >/sys/devices/cpu/allow_tsx_force_abort Events are again spread over the 4 counters: 10.017096277 124,276,230,565 branches [74.96%] 10.017237209 124,228,062,171 branches [75.03%] 10.017478637 124,178,780,626 branches [75.03%] 10.017853402 124,198,316,177 branches [75.03%] 11.018334423 124,602,418,933 branches [85.40%] 11.018722584 124,602,921,320 branches [85.42%] 11.019095621 124,603,956,093 branches [85.42%] 11.019467742 124,595,273,783 branches [85.42%] 12.019945736 125,110,114,864 branches 12.020330764 125,109,334,472 branches 12.020688740 125,109,818,865 branches 12.021054020 125,108,594,014 branches 13.021516774 125,109,164,018 branches 13.021903640 125,108,794,510 branches 13.022270770 125,107,756,978 branches 13.022630819 125,109,380,471 branches 14.023114989 125,133,140,817 branches 14.023501880 125,133,785,858 branches 14.023868339 125,133,852,700 branches Signed-off-by: Stephane Eranian <eranian@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: 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> Cc: kan.liang@intel.com Cc: nelson.dsouza@intel.com Cc: tonyj@suse.com Link: https://lkml.kernel.org/r/20190408173252.37932-3-eranian@google.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-16Merge branch 'perf/urgent' into perf/core, to pick up fixesIngo Molnar2-20/+20
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-16perf/x86: Fix incorrect PEBS_REGSKan Liang2-20/+20
PEBS_REGS used as mask for the supported registers for large PEBS. However, the mask cannot filter the sample_regs_user/sample_regs_intr correctly. (1ULL << PERF_REG_X86_*) should be used to replace PERF_REG_X86_*, which is only the index. Rename PEBS_REGS to PEBS_GP_REGS, because the mask is only for general purpose registers. Signed-off-by: Kan Liang <kan.liang@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: <stable@vger.kernel.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 Cc: jolsa@kernel.org Fixes: 2fe1bc1f501d ("perf/x86: Enable free running PEBS for REGS_USER/INTR") Link: https://lkml.kernel.org/r/20190402194509.2832-2-kan.liang@linux.intel.com [ Renamed it to PEBS_GP_REGS - as 'GPRS' is used elsewhere ;-) ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-16Merge branch 'linus' into perf/core, to pick up fixesIngo Molnar3-16/+145
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-10x86/perf/amd: Remove need to check "running" bit in NMI handlerLendacky, Thomas2-12/+22
Spurious interrupt support was added to perf in the following commit, almost a decade ago: 63e6be6d98e1 ("perf, x86: Catch spurious interrupts after disabling counters") The two previous patches (resolving the race condition when disabling a PMC and NMI latency mitigation) allow for the removal of this older spurious interrupt support. Currently in x86_pmu_stop(), the bit for the PMC in the active_mask bitmap is cleared before disabling the PMC, which sets up a race condition. This race condition was mitigated by introducing the running bitmap. That race condition can be eliminated by first disabling the PMC, waiting for PMC reset on overflow and then clearing the bit for the PMC in the active_mask bitmap. The NMI handler will not re-enable a disabled counter. If x86_pmu_stop() is called from the perf NMI handler, the NMI latency mitigation support will guard against any unhandled NMI messages. Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: <stable@vger.kernel.org> # 4.14.x- 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: Borislav Petkov <bp@alien8.de> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> 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> Link: https://lkml.kernel.org/r/Message-ID: Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-03x86/perf/amd: Resolve NMI latency issues for active PMCsLendacky, Thomas1-1/+55
On AMD processors, the detection of an overflowed PMC counter in the NMI handler relies on the current value of the PMC. So, for example, to check for overflow on a 48-bit counter, bit 47 is checked to see if it is 1 (not overflowed) or 0 (overflowed). When the perf NMI handler executes it does not know in advance which PMC counters have overflowed. As such, the NMI handler will process all active PMC counters that have overflowed. NMI latency in newer AMD processors can result in multiple overflowed PMC counters being processed in one NMI and then a subsequent NMI, that does not appear to be a back-to-back NMI, not finding any PMC counters that have overflowed. This may appear to be an unhandled NMI resulting in either a panic or a series of messages, depending on how the kernel was configured. To mitigate this issue, add an AMD handle_irq callback function, amd_pmu_handle_irq(), that will invoke the common x86_pmu_handle_irq() function and upon return perform some additional processing that will indicate if the NMI has been handled or would have been handled had an earlier NMI not handled the overflowed PMC. Using a per-CPU variable, a minimum value of the number of active PMCs or 2 will be set whenever a PMC is active. This is used to indicate the possible number of NMIs that can still occur. The value of 2 is used for when an NMI does not arrive at the LAPIC in time to be collapsed into an already pending NMI. Each time the function is called without having handled an overflowed counter, the per-CPU value is checked. If the value is non-zero, it is decremented and the NMI indicates that it handled the NMI. If the value is zero, then the NMI indicates that it did not handle the NMI. Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: <stable@vger.kernel.org> # 4.14.x- 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: Borislav Petkov <bp@alien8.de> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> 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> Link: https://lkml.kernel.org/r/Message-ID: Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-03x86/perf/amd: Resolve race condition when disabling PMCLendacky, Thomas1-3/+62
On AMD processors, the detection of an overflowed counter in the NMI handler relies on the current value of the counter. So, for example, to check for overflow on a 48 bit counter, bit 47 is checked to see if it is 1 (not overflowed) or 0 (overflowed). There is currently a race condition present when disabling and then updating the PMC. Increased NMI latency in newer AMD processors makes this race condition more pronounced. If the counter value has overflowed, it is possible to update the PMC value before the NMI handler can run. The updated PMC value is not an overflowed value, so when the perf NMI handler does run, it will not find an overflowed counter. This may appear as an unknown NMI resulting in either a panic or a series of messages, depending on how the kernel is configured. To eliminate this race condition, the PMC value must be checked after disabling the counter. Add an AMD function, amd_pmu_disable_all(), that will wait for the NMI handler to reset any active and overflowed counter after calling x86_pmu_disable_all(). Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: <stable@vger.kernel.org> # 4.14.x- 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: Borislav Petkov <bp@alien8.de> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> 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> Link: https://lkml.kernel.org/r/Message-ID: Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-03perf/x86/intel: Initialize TFA MSRPeter Zijlstra1-0/+6
Stephane reported that the TFA MSR is not initialized by the kernel, but the TFA bit could set by firmware or as a leftover from a kexec, which makes the state inconsistent. Reported-by: Stephane Eranian <eranian@google.com> Tested-by: Nelson DSouza <nelson.dsouza@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: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: tonyj@suse.com Link: https://lkml.kernel.org/r/20190321123849.GN6521@hirez.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-03perf/x86/intel: Fix handling of wakeup_events for multi-entry PEBSStephane Eranian1-1/+1
When an event is programmed with attr.wakeup_events=N (N>0), it means the caller is interested in getting a user level notification after N samples have been recorded in the kernel sampling buffer. With precise events on Intel processors, the kernel uses PEBS. The kernel tries minimize sampling overhead by verifying if the event configuration is compatible with multi-entry PEBS mode. If so, the kernel is notified only when the buffer has reached its threshold. Other PEBS operates in single-entry mode, the kenrel is notified for each PEBS sample. The problem is that the current implementation look at frequency mode and event sample_type but ignores the wakeup_events field. Thus, it may not be possible to receive a notification after each precise event. This patch fixes this problem by disabling multi-entry PEBS if wakeup_events is non-zero. Signed-off-by: Stephane Eranian <eranian@google.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Andi Kleen <ak@linux.intel.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> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: kan.liang@intel.com Link: https://lkml.kernel.org/r/20190306195048.189514-1-eranian@google.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-03perf/x86: Add sanity checks to x86_schedule_events()Peter Zijlstra1-13/+19
By computing the 'committed' index earlier, we can use it to validate the cached constraint state. 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> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-03perf/x86: Optimize x86_schedule_events()Peter Zijlstra2-3/+13
Now that cpuc->event_constraint[] is retained, we can avoid calling get_event_constraints() over and over again. 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> Signed-off-by: Ingo Molnar <mingo@kernel.org>