Commit Graph

91 Commits

Author SHA1 Message Date
Linus Torvalds 1f2d9ffc7a Scheduler updates in this cycle are:
- Improve the scalability of the CFS bandwidth unthrottling logic
    with large number of CPUs.
 
  - Fix & rework various cpuidle routines, simplify interaction with
    the generic scheduler code. Add __cpuidle methods as noinstr to
    objtool's noinstr detection and fix boatloads of cpuidle bugs & quirks.
 
  - Add new ABI: introduce MEMBARRIER_CMD_GET_REGISTRATIONS,
    to query previously issued registrations.
 
  - Limit scheduler slice duration to the sysctl_sched_latency period,
    to improve scheduling granularity with a large number of SCHED_IDLE
    tasks.
 
  - Debuggability enhancement on sys_exit(): warn about disabled IRQs,
    but also enable them to prevent a cascade of followup problems and
    repeat warnings.
 
  - Fix the rescheduling logic in prio_changed_dl().
 
  - Micro-optimize cpufreq and sched-util methods.
 
  - Micro-optimize ttwu_runnable()
 
  - Micro-optimize the idle-scanning in update_numa_stats(),
    select_idle_capacity() and steal_cookie_task().
 
  - Update the RSEQ code & self-tests
 
  - Constify various scheduler methods
 
  - Remove unused methods
 
  - Refine __init tags
 
  - Documentation updates
 
  - ... Misc other cleanups, fixes
 
 Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'sched-core-2023-02-20' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull scheduler updates from Ingo Molnar:

 - Improve the scalability of the CFS bandwidth unthrottling logic with
   large number of CPUs.

 - Fix & rework various cpuidle routines, simplify interaction with the
   generic scheduler code. Add __cpuidle methods as noinstr to objtool's
   noinstr detection and fix boatloads of cpuidle bugs & quirks.

 - Add new ABI: introduce MEMBARRIER_CMD_GET_REGISTRATIONS, to query
   previously issued registrations.

 - Limit scheduler slice duration to the sysctl_sched_latency period, to
   improve scheduling granularity with a large number of SCHED_IDLE
   tasks.

 - Debuggability enhancement on sys_exit(): warn about disabled IRQs,
   but also enable them to prevent a cascade of followup problems and
   repeat warnings.

 - Fix the rescheduling logic in prio_changed_dl().

 - Micro-optimize cpufreq and sched-util methods.

 - Micro-optimize ttwu_runnable()

 - Micro-optimize the idle-scanning in update_numa_stats(),
   select_idle_capacity() and steal_cookie_task().

 - Update the RSEQ code & self-tests

 - Constify various scheduler methods

 - Remove unused methods

 - Refine __init tags

 - Documentation updates

 - Misc other cleanups, fixes

* tag 'sched-core-2023-02-20' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (110 commits)
  sched/rt: pick_next_rt_entity(): check list_entry
  sched/deadline: Add more reschedule cases to prio_changed_dl()
  sched/fair: sanitize vruntime of entity being placed
  sched/fair: Remove capacity inversion detection
  sched/fair: unlink misfit task from cpu overutilized
  objtool: mem*() are not uaccess safe
  cpuidle: Fix poll_idle() noinstr annotation
  sched/clock: Make local_clock() noinstr
  sched/clock/x86: Mark sched_clock() noinstr
  x86/pvclock: Improve atomic update of last_value in pvclock_clocksource_read()
  x86/atomics: Always inline arch_atomic64*()
  cpuidle: tracing, preempt: Squash _rcuidle tracing
  cpuidle: tracing: Warn about !rcu_is_watching()
  cpuidle: lib/bug: Disable rcu_is_watching() during WARN/BUG
  cpuidle: drivers: firmware: psci: Dont instrument suspend code
  KVM: selftests: Fix build of rseq test
  exit: Detect and fix irq disabled state in oops
  cpuidle, arm64: Fix the ARM64 cpuidle logic
  cpuidle: mvebu: Fix duplicate flags assignment
  sched/fair: Limit sched slice duration
  ...
2023-02-20 17:41:08 -08:00
Mark Rutland 61d0386273 arm_pmu: fix event CPU filtering
Janne reports that perf has been broken on Apple M1 as of commit:

  bd27568117 ("perf: Rewrite core context handling")

That commit replaced the pmu::filter_match() callback with
pmu::filter(), whose return value has the opposite polarity, with true
implying events should be ignored rather than scheduled. While an
attempt was made to update the logic in armv8pmu_filter() and
armpmu_filter() accordingly, the return value remains inverted in a
couple of cases:

* If the arm_pmu does not have an arm_pmu::filter() callback,
  armpmu_filter() will always return whether the CPU is supported rather
  than whether the CPU is not supported.

  As a result, the perf core will not schedule events on supported CPUs,
  resulting in a loss of events. Additionally, the perf core will
  attempt to schedule events on unsupported CPUs, but this will be
  rejected by armpmu_add(), which may result in a loss of events from
  other PMUs on those unsupported CPUs.

* If the arm_pmu does have an arm_pmu::filter() callback, and
  armpmu_filter() is called on a CPU which is not supported by the
  arm_pmu, armpmu_filter() will return false rather than true.

  As a result, the perf core will attempt to schedule events on
  unsupported CPUs, but this will be rejected by armpmu_add(), which may
  result in a loss of events from other PMUs on those unsupported CPUs.

This means a loss of events can be seen with any arm_pmu driver, but
with the ARMv8 PMUv3 driver (which is the only arm_pmu driver with an
arm_pmu::filter() callback) the event loss will be more limited and may
go unnoticed, which is how this issue evaded testing so far.

Fix the CPU filtering by performing this consistently in
armpmu_filter(), and remove the redundant arm_pmu::filter() callback and
armv8pmu_filter() implementation.

Commit bd27568117 also silently removed the CHAIN event filtering from
armv8pmu_filter(), which will be addressed by a separate patch without
using the filter callback.

Fixes: bd27568117 ("perf: Rewrite core context handling")
Reported-by: Janne Grunau <j@jannau.net>
Link: https://lore.kernel.org/asahi/20230215-arm_pmu_m1_regression-v1-1-f5a266577c8d@jannau.net/
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@amd.com>
Cc: Asahi Lina <lina@asahilina.net>
Cc: Eric Curtin <ecurtin@redhat.com>
Tested-by: Janne Grunau <j@jannau.net>
Link: https://lore.kernel.org/r/20230216141240.3833272-2-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2023-02-16 21:23:52 +00:00
Peter Zijlstra 1c38b0615f arm64, riscv, perf: Remove RCU_NONIDLE() usage
The PM notifiers should no longer be ran with RCU disabled (per the
previous patches), as such this hack is no longer required either.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Tony Lindgren <tony@atomide.com>
Tested-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/r/20230112195542.151174682@infradead.org
2023-01-13 11:48:17 +01:00
Linus Torvalds add7695957 Perf events updates for v6.2:
- Thoroughly rewrite the data structures that implement perf task context handling,
    with the goal of fixing various quirks and unfeatures both in already merged,
    and in upcoming proposed code.
 
    The old data structure is the per task and per cpu perf_event_contexts:
 
          task_struct::perf_events_ctxp[] <-> perf_event_context <-> perf_cpu_context
               ^                                 |    ^     |           ^
               `---------------------------------'    |     `--> pmu ---'
                                                      v           ^
                                                 perf_event ------'
 
    In this new design this is replaced with a single task context and
    a single CPU context, plus intermediate data-structures:
 
          task_struct::perf_event_ctxp -> perf_event_context <- perf_cpu_context
               ^                           |   ^ ^
               `---------------------------'   | |
                                               | |    perf_cpu_pmu_context <--.
                                               | `----.    ^                  |
                                               |      |    |                  |
                                               |      v    v                  |
                                               | ,--> perf_event_pmu_context  |
                                               | |                            |
                                               | |                            |
                                               v v                            |
                                          perf_event ---> pmu ----------------'
 
    [ See commit bd27568117 for more details. ]
 
    This rewrite was developed by Peter Zijlstra and Ravi Bangoria.
 
  - Optimize perf_tp_event()
 
  - Update the Intel uncore PMU driver, extending it with UPI topology discovery
    on various hardware models.
 
  - Misc fixes & cleanups
 
 Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'perf-core-2022-12-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull perf events updates from Ingo Molnar:

 - Thoroughly rewrite the data structures that implement perf task
   context handling, with the goal of fixing various quirks and
   unfeatures both in already merged, and in upcoming proposed code.

   The old data structure is the per task and per cpu
   perf_event_contexts:

         task_struct::perf_events_ctxp[] <-> perf_event_context <-> perf_cpu_context
              ^                                 |    ^     |           ^
              `---------------------------------'    |     `--> pmu ---'
                                                     v           ^
                                                perf_event ------'

   In this new design this is replaced with a single task context and a
   single CPU context, plus intermediate data-structures:

         task_struct::perf_event_ctxp -> perf_event_context <- perf_cpu_context
              ^                           |   ^ ^
              `---------------------------'   | |
                                              | |    perf_cpu_pmu_context <--.
                                              | `----.    ^                  |
                                              |      |    |                  |
                                              |      v    v                  |
                                              | ,--> perf_event_pmu_context  |
                                              | |                            |
                                              | |                            |
                                              v v                            |
                                         perf_event ---> pmu ----------------'

   [ See commit bd27568117 for more details. ]

   This rewrite was developed by Peter Zijlstra and Ravi Bangoria.

 - Optimize perf_tp_event()

 - Update the Intel uncore PMU driver, extending it with UPI topology
   discovery on various hardware models.

 - Misc fixes & cleanups

* tag 'perf-core-2022-12-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (25 commits)
  perf/x86/intel/uncore: Fix reference count leak in __uncore_imc_init_box()
  perf/x86/intel/uncore: Fix reference count leak in snr_uncore_mmio_map()
  perf/x86/intel/uncore: Fix reference count leak in hswep_has_limit_sbox()
  perf/x86/intel/uncore: Fix reference count leak in sad_cfg_iio_topology()
  perf/x86/intel/uncore: Make set_mapping() procedure void
  perf/x86/intel/uncore: Update sysfs-devices-mapping file
  perf/x86/intel/uncore: Enable UPI topology discovery for Sapphire Rapids
  perf/x86/intel/uncore: Enable UPI topology discovery for Icelake Server
  perf/x86/intel/uncore: Get UPI NodeID and GroupID
  perf/x86/intel/uncore: Enable UPI topology discovery for Skylake Server
  perf/x86/intel/uncore: Generalize get_topology() for SKX PMUs
  perf/x86/intel/uncore: Disable I/O stacks to PMU mapping on ICX-D
  perf/x86/intel/uncore: Clear attr_update properly
  perf/x86/intel/uncore: Introduce UPI topology type
  perf/x86/intel/uncore: Generalize IIO topology support
  perf/core: Don't allow grouping events from different hw pmus
  perf/amd/ibs: Make IBS a core pmu
  perf: Fix function pointer case
  perf/x86/amd: Remove the repeated declaration
  perf: Fix possible memleak in pmu_dev_alloc()
  ...
2022-12-12 15:19:38 -08:00
Will Deacon 10162e78ea Merge branch 'for-next/perf' into for-next/core
* for-next/perf: (21 commits)
  arm_pmu: Drop redundant armpmu->map_event() in armpmu_event_init()
  drivers/perf: hisi: Add TLP filter support
  Documentation: perf: Indent filter options list of hisi-pcie-pmu
  docs: perf: Fix PMU instance name of hisi-pcie-pmu
  drivers/perf: hisi: Fix some event id for hisi-pcie-pmu
  arm64/perf: Replace PMU version number '0' with ID_AA64DFR0_EL1_PMUVer_NI
  perf/amlogic: Remove unused header inclusions of  <linux/version.h>
  perf/amlogic: Fix build error for x86_64 allmodconfig
  dt-binding: perf: Add Amlogic DDR PMU
  docs/perf: Add documentation for the Amlogic G12 DDR PMU
  perf/amlogic: Add support for Amlogic meson G12 SoC DDR PMU driver
  MAINTAINERS: Update HiSilicon PMU maintainers
  perf: arm_cspmu: Fix module cyclic dependency
  perf: arm_cspmu: Fix build failure on x86_64
  perf: arm_cspmu: Fix modular builds due to missing MODULE_LICENSE()s
  perf: arm_cspmu: Add support for NVIDIA SCF and MCF attribute
  perf: arm_cspmu: Add support for ARM CoreSight PMU driver
  perf/smmuv3: Fix hotplug callback leak in arm_smmu_pmu_init()
  perf/arm_dmc620: Fix hotplug callback leak in dmc620_pmu_init()
  drivers: perf: marvell_cn10k: Fix hotplug callback leak in tad_pmu_init()
  ...
2022-12-06 11:22:48 +00:00
Anshuman Khandual 4361251cef arm_pmu: Drop redundant armpmu->map_event() in armpmu_event_init()
__hw_perf_event_init() already calls armpmu->map_event() callback, and also
returns its error code including -ENOENT, along with a debug callout. Hence
an additional armpmu->map_event() check for -ENOENT is redundant.

Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Link: https://lore.kernel.org/r/20221202015611.338499-1-anshuman.khandual@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2022-12-02 10:15:03 +00:00
Mark Rutland fe40ffdb76 arm_pmu: rework ACPI probing
The current ACPI PMU probing logic tries to associate PMUs with CPUs
when the CPU is first brought online, in order to handle late hotplug,
though PMUs are only registered during early boot, and so for late
hotplugged CPUs this can only associate the CPU with an existing PMU.

We tried to be clever and the have the arm_pmu_acpi_cpu_starting()
callback allocate a struct arm_pmu when no matching instance is found,
in order to avoid duplication of logic. However, as above this doesn't
do anything useful for late hotplugged CPUs, and this requires us to
allocate memory in an atomic context, which is especially problematic
for PREEMPT_RT, as reported by Valentin and Pierre.

This patch reworks the probing to detect PMUs for all online CPUs in the
arm_pmu_acpi_probe() function, which is more aligned with how DT probing
works. The arm_pmu_acpi_cpu_starting() callback only tries to associate
CPUs with an existing arm_pmu instance, avoiding the problem of
allocating in atomic context.

Note that as we didn't previously register PMUs for late-hotplugged
CPUs, this change doesn't result in a loss of existing functionality,
though we will now warn when we cannot associate a CPU with a PMU.

This change allows us to pull the hotplug callback registration into the
arm_pmu_acpi_probe() function, as we no longer need the callbacks to be
invoked shortly after probing the boot CPUs, and can register it without
invoking the calls.

For the moment the arm_pmu_acpi_init() initcall remains to register the
SPE PMU, though in future this should probably be moved elsewhere (e.g.
the arm64 ACPI init code), since this doesn't need to be tied to the
regular CPU PMU code.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reported-by: Valentin Schneider <valentin.schneider@arm.com>
Link: https://lore.kernel.org/r/20210810134127.1394269-2-valentin.schneider@arm.com/
Reported-by: Pierre Gondois <pierre.gondois@arm.com>
Link: https://lore.kernel.org/linux-arm-kernel/20220912155105.1443303-1-pierre.gondois@arm.com/
Cc: Pierre Gondois <pierre.gondois@arm.com>
Cc: Valentin Schneider <vschneid@redhat.com>
Cc: Will Deacon <will@kernel.org>
Reviewed-and-tested-by: Pierre Gondois <pierre.gondois@arm.com>
Link: https://lore.kernel.org/r/20220930111844.1522365-4-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2022-11-07 16:16:20 +00:00
Peter Zijlstra bd27568117 perf: Rewrite core context handling
There have been various issues and limitations with the way perf uses
(task) contexts to track events. Most notable is the single hardware
PMU task context, which has resulted in a number of yucky things (both
proposed and merged).

Notably:
 - HW breakpoint PMU
 - ARM big.little PMU / Intel ADL PMU
 - Intel Branch Monitoring PMU
 - AMD IBS PMU
 - S390 cpum_cf PMU
 - PowerPC trace_imc PMU

*Current design:*

Currently we have a per task and per cpu perf_event_contexts:

  task_struct::perf_events_ctxp[] <-> perf_event_context <-> perf_cpu_context
       ^                                 |    ^     |           ^
       `---------------------------------'    |     `--> pmu ---'
                                              v           ^
                                         perf_event ------'

Each task has an array of pointers to a perf_event_context. Each
perf_event_context has a direct relation to a PMU and a group of
events for that PMU. The task related perf_event_context's have a
pointer back to that task.

Each PMU has a per-cpu pointer to a per-cpu perf_cpu_context, which
includes a perf_event_context, which again has a direct relation to
that PMU, and a group of events for that PMU.

The perf_cpu_context also tracks which task context is currently
associated with that CPU and includes a few other things like the
hrtimer for rotation etc.

Each perf_event is then associated with its PMU and one
perf_event_context.

*Proposed design:*

New design proposed by this patch reduce to a single task context and
a single CPU context but adds some intermediate data-structures:

  task_struct::perf_event_ctxp -> perf_event_context <- perf_cpu_context
       ^                           |   ^ ^
       `---------------------------'   | |
                                       | |    perf_cpu_pmu_context <--.
                                       | `----.    ^                  |
                                       |      |    |                  |
                                       |      v    v                  |
                                       | ,--> perf_event_pmu_context  |
                                       | |                            |
                                       | |                            |
                                       v v                            |
                                  perf_event ---> pmu ----------------'

With the new design, perf_event_context will hold all events for all
pmus in the (respective pinned/flexible) rbtrees. This can be achieved
by adding pmu to rbtree key:

  {cpu, pmu, cgroup, group_index}

Each perf_event_context carries a list of perf_event_pmu_context which
is used to hold per-pmu-per-context state. For example, it keeps track
of currently active events for that pmu, a pmu specific task_ctx_data,
a flag to tell whether rotation is required or not etc.

Additionally, perf_cpu_pmu_context is used to hold per-pmu-per-cpu
state like hrtimer details to drive the event rotation, a pointer to
perf_event_pmu_context of currently running task and some other
ancillary information.

Each perf_event is associated to it's pmu, perf_event_context and
perf_event_pmu_context.

Further optimizations to current implementation are possible. For
example, ctx_resched() can be optimized to reschedule only single pmu
events.

Much thanks to Ravi for picking this up and pushing it towards
completion.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Co-developed-by: Ravi Bangoria <ravi.bangoria@amd.com>
Signed-off-by: Ravi Bangoria <ravi.bangoria@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20221008062424.313-1-ravi.bangoria@amd.com
2022-10-27 20:12:16 +02:00
James Clark cbb0c02caf perf: arm64: Add SVE vector granule register to user regs
Dwarf based unwinding in a function that pushes SVE registers onto
the stack requires the unwinder to know the length of the SVE register
to calculate the stack offsets correctly. This was added to the Arm
specific Dwarf spec as the VG pseudo register[1].

Add the vector length at position 46 if it's requested by userspace and
SVE is supported. If it's not supported then fail to open the event.

The vector length must be on each sample because it can be changed
at runtime via a prctl or ptrace call. Also by adding it as a register
rather than a separate attribute, minimal changes will be required in an
unwinder that already indexes into the register list.

[1]: https://github.com/ARM-software/abi-aa/blob/main/aadwarf64/aadwarf64.rst

Reviewed-by: Mark Brown <broonie@kernel.org>
Signed-off-by: James Clark <james.clark@arm.com>
Link: https://lore.kernel.org/r/20220901132658.1024635-2-james.clark@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2022-09-22 15:06:02 +01:00
Rob Herring e5c23779f9 arm_pmu: Validate single/group leader events
In the case where there is only a cycle counter available (i.e.
PMCR_EL0.N is 0) and an event other than CPU cycles is opened, the open
should fail as the event can never possibly be scheduled. However, the
event validation when an event is opened is skipped when the group
leader is opened. Fix this by always validating the group leader events.

Reported-by: Al Grant <al.grant@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20220408203330.4014015-1-robh@kernel.org
Cc: <stable@vger.kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
2022-04-13 11:48:45 +01:00
Will Deacon 0162052214 Merge branch 'for-next/perf-m1' into for-next/perf
Support for the CPU PMUs on the Apple M1.

* for-next/perf-m1:
  drivers/perf: Add Apple icestorm/firestorm CPU PMU driver
  drivers/perf: arm_pmu: Handle 47 bit counters
  irqchip/apple-aic: Move PMU-specific registers to their own include file
  arm64: dts: apple: Add t8303 PMU nodes
  arm64: dts: apple: Add t8103 PMU interrupt affinities
  irqchip/apple-aic: Wire PMU interrupts
  irqchip/apple-aic: Parse FIQ affinities from device-tree
  dt-bindings: apple,aic: Add affinity description for per-cpu pseudo-interrupts
  dt-bindings: apple,aic: Add CPU PMU per-cpu pseudo-interrupts
  dt-bindings: arm-pmu: Document Apple PMU compatible strings
2022-03-08 13:33:34 +00:00
Marc Zyngier 1280f12f56 drivers/perf: arm_pmu: Handle 47 bit counters
The current ARM PMU framework can only deal with 32 or 64bit counters.
Teach it about a 47bit flavour.

Yes, this is odd.

Reviewed-by: Hector Martin <marcan@marcan.st>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
2022-03-08 13:32:48 +00:00
Yury Norov 95ed57c73b perf: replace bitmap_weight with bitmap_empty where appropriate
In some places, drivers/perf code calls bitmap_weight() to check if any
bit of a given bitmap is set. It's better to use bitmap_empty() in that
case because bitmap_empty() stops traversing the bitmap as soon as it
finds first set bit, while bitmap_weight() counts all bits unconditionally.

Signed-off-by: Yury Norov <yury.norov@gmail.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20220210224933.379149-13-yury.norov@gmail.com
Signed-off-by: Will Deacon <will@kernel.org>
2022-02-15 14:38:57 +00:00
Marc Zyngier e840f42a49 KVM: arm64: Fix PMU probe ordering
Russell reported that since 5.13, KVM's probing of the PMU has
started to fail on his HW. As it turns out, there is an implicit
ordering dependency between the architectural PMU probing code and
and KVM's own probing. If, due to probe ordering reasons, KVM probes
before the PMU driver, it will fail to detect the PMU and prevent it
from being advertised to guests as well as the VMM.

Obviously, this is one probing too many, and we should be able to
deal with any ordering.

Add a callback from the PMU code into KVM to advertise the registration
of a host CPU PMU, allowing for any probing order.

Fixes: 5421db1be3 ("KVM: arm64: Divorce the perf code from oprofile helpers")
Reported-by: "Russell King (Oracle)" <linux@armlinux.org.uk>
Tested-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/YUYRKVflRtUytzy5@shell.armlinux.org.uk
Cc: stable@vger.kernel.org
2021-09-20 12:43:34 +01:00
Tian Tao 3c1f2eb547 arm_pmu: move to use request_irq by IRQF_NO_AUTOEN flag
request_irq() after setting IRQ_NOAUTOEN as below
irq_set_status_flags(irq, IRQ_NOAUTOEN);
request_irq(dev, irq...);
can be replaced by request_irq() with IRQF_NO_AUTOEN flag.

this patch is made base on "add IRQF_NO_AUTOEN for request_irq" which
is being merged: https://lore.kernel.org/patchwork/patch/1388765/

Signed-off-by: Tian Tao <tiantao6@hisilicon.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/1622595642-61678-2-git-send-email-tiantao6@hisilicon.com
Signed-off-by: Will Deacon <will@kernel.org>
2021-06-02 12:48:08 +01:00
YueHaibing 29c043760e perf: arm_pmu: use DEVICE_ATTR_RO macro
Use DEVICE_ATTR_RO helper instead of plain DEVICE_ATTR,
which makes the code a bit shorter and easier to read.

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20210528014130.7708-1-yuehaibing@huawei.com
Signed-off-by: Will Deacon <will@kernel.org>
2021-06-01 14:22:44 +01:00
Junhao He f265fd166b drivers/perf: arm_pmu: Fix some coding style issues
Fix some coding style issues reported by checkpatch.pl, including
following types:

ERROR: spaces required around that '=' (ctx:VxW)
WARNING: Possible unnecessary 'out of memory' message

Signed-off-by: Junhao He <hejunhao2@hisilicon.com>
Signed-off-by: Jay Fang <f.fangjian@huawei.com>
Link: https://lore.kernel.org/r/1620736054-58412-3-git-send-email-f.fangjian@huawei.com
Signed-off-by: Will Deacon <will@kernel.org>
2021-05-25 18:59:23 +01:00
Marc Zyngier e9c74a686a arm64: Get rid of oprofile leftovers
perf_pmu_name() and perf_num_counters() are now unused. Drop them.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Acked-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20210414134409.1266357-3-maz@kernel.org
2021-04-22 13:32:39 +01:00
Rikard Falkeborn f0c140481d perf: Constify static struct attribute_group
The only usage is to put their addresses in an array of pointers to
const struct attribute group. Make them const to allow the compiler
to put them in read-only memory.

Signed-off-by: Rikard Falkeborn <rikard.falkeborn@gmail.com>
Link: https://lore.kernel.org/r/20210117212847.21319-5-rikard.falkeborn@gmail.com
Signed-off-by: Will Deacon <will@kernel.org>
2021-01-20 17:51:23 +00:00
Will Deacon b90d72a6bf Revert "arm64: Enable perf events based hard lockup detector"
This reverts commit 367c820ef0.

lockup_detector_init() makes heavy use of per-cpu variables and must be
called with preemption disabled. Usually, it's handled early during boot
in kernel_init_freeable(), before SMP has been initialised.

Since we do not know whether or not our PMU interrupt can be signalled
as an NMI until considerably later in the boot process, the Arm PMU
driver attempts to re-initialise the lockup detector off the back of a
device_initcall(). Unfortunately, this is called from preemptible
context and results in the following splat:

  | BUG: using smp_processor_id() in preemptible [00000000] code: swapper/0/1
  | caller is debug_smp_processor_id+0x20/0x2c
  | CPU: 2 PID: 1 Comm: swapper/0 Not tainted 5.10.0+ #276
  | Hardware name: linux,dummy-virt (DT)
  | Call trace:
  |   dump_backtrace+0x0/0x3c0
  |   show_stack+0x20/0x6c
  |   dump_stack+0x2f0/0x42c
  |   check_preemption_disabled+0x1cc/0x1dc
  |   debug_smp_processor_id+0x20/0x2c
  |   hardlockup_detector_event_create+0x34/0x18c
  |   hardlockup_detector_perf_init+0x2c/0x134
  |   watchdog_nmi_probe+0x18/0x24
  |   lockup_detector_init+0x44/0xa8
  |   armv8_pmu_driver_init+0x54/0x78
  |   do_one_initcall+0x184/0x43c
  |   kernel_init_freeable+0x368/0x380
  |   kernel_init+0x1c/0x1cc
  |   ret_from_fork+0x10/0x30

Rather than bodge this with raw_smp_processor_id() or randomly disabling
preemption, simply revert the culprit for now until we figure out how to
do this properly.

Reported-by: Lecopzer Chen <lecopzer.chen@mediatek.com>
Signed-off-by: Will Deacon <will@kernel.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Cc: Sumit Garg <sumit.garg@linaro.org>
Cc: Alexandru Elisei <alexandru.elisei@arm.com>
Link: https://lore.kernel.org/r/20201221162249.3119-1-lecopzer.chen@mediatek.com
Link: https://lore.kernel.org/r/20210112221855.10666-1-will@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2021-01-13 15:08:41 +00:00
Sumit Garg 367c820ef0 arm64: Enable perf events based hard lockup detector
With the recent feature added to enable perf events to use pseudo NMIs
as interrupts on platforms which support GICv3 or later, its now been
possible to enable hard lockup detector (or NMI watchdog) on arm64
platforms. So enable corresponding support.

One thing to note here is that normally lockup detector is initialized
just after the early initcalls but PMU on arm64 comes up much later as
device_initcall(). So we need to re-initialize lockup detection once
PMU has been initialized.

Signed-off-by: Sumit Garg <sumit.garg@linaro.org>
Acked-by: Alexandru Elisei <alexandru.elisei@arm.com>
Link: https://lore.kernel.org/r/1602060704-10921-1-git-send-email-sumit.garg@linaro.org
Signed-off-by: Will Deacon <will@kernel.org>
2020-11-25 15:18:39 +00:00
Julien Thierry d8f6267f7c arm_pmu: arm64: Use NMIs for PMU
Add required PMU interrupt operations for NMIs. Request interrupt lines as
NMIs when possible, otherwise fall back to normal interrupts.

NMIs are only supported on the arm64 architecture with a GICv3 irqchip.

[Alexandru E.: Added that NMIs only work on arm64 + GICv3, print message
	when PMU is using NMIs]

Signed-off-by: Julien Thierry <julien.thierry@arm.com>
Signed-off-by: Alexandru Elisei <alexandru.elisei@arm.com>
Tested-by: Sumit Garg <sumit.garg@linaro.org> (Developerbox)
Cc: Julien Thierry <julien.thierry.kdev@gmail.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20200924110706.254996-8-alexandru.elisei@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2020-09-28 19:00:17 +01:00
Julien Thierry f76b130bdb arm_pmu: Introduce pmu_irq_ops
Currently the PMU interrupt can either be a normal irq or a percpu irq.
Supporting NMI will introduce two cases for each existing one. It becomes
a mess of 'if's when managing the interrupt.

Define sets of callbacks for operations commonly done on the interrupt. The
appropriate set of callbacks is selected at interrupt request time and
simplifies interrupt enabling/disabling and freeing.

Signed-off-by: Julien Thierry <julien.thierry@arm.com>
Signed-off-by: Alexandru Elisei <alexandru.elisei@arm.com>
Tested-by: Sumit Garg <sumit.garg@linaro.org> (Developerbox)
Cc: Julien Thierry <julien.thierry.kdev@gmail.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20200924110706.254996-7-alexandru.elisei@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2020-09-28 19:00:17 +01:00
Will Deacon 0d7fd70f26 drivers/perf: arm_pmu: Fix failure path in PM notifier
Handling of the CPU_PM_ENTER_FAILED transition in the Arm PMU PM
notifier code incorrectly skips restoration of the counters. Fix the
logic so that CPU_PM_ENTER_FAILED follows the same path as CPU_PM_EXIT.

Cc: <stable@vger.kernel.org>
Fixes: da4e4f18af ("drivers/perf: arm_pmu: implement CPU_PM notifier")
Reported-by: Anders Roxell <anders.roxell@linaro.org>
Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
2019-07-29 11:43:48 +01:00
Thomas Gleixner 457c899653 treewide: Add SPDX license identifier for missed files
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>
2019-05-21 10:50:45 +02:00
Andrew Murray 1d899c0e9b perf/core, arch/arm: Use PERF_PMU_CAP_NO_EXCLUDE conditionally
The ARM PMU driver can be used to represent a variety of ARM based
PMUs. Some of these PMUs do not provide support for context
exclusion, where this is the case we advertise the
PERF_PMU_CAP_NO_EXCLUDE capability to ensure that perf prevents us
from handling events where any exclusion flags are set.

Where an ARM PMU driver has the set_event_filter function implemented,
we rely on it to perform exclusion checks. At present some of these
functions do not test for all of the available exclude flags.

Signed-off-by: Andrew Murray <andrew.murray@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: robin.murphy@arm.com
Cc: suzuki.poulose@arm.com
Link: https://lkml.kernel.org/r/1547128414-50693-6-git-send-email-andrew.murray@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-01-21 11:01:22 +01:00
Will Deacon ca2b497253 arm64: perf: Reject stand-alone CHAIN events for PMUv3
It doesn't make sense for a perf event to be configured as a CHAIN event
in isolation, so extend the arm_pmu structure with a ->filter_match()
function to allow the backend PMU implementation to reject CHAIN events
early.

Cc: <stable@vger.kernel.org>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-10-12 15:25:17 +01:00
Suzuki K Poulose c132079053 arm64: perf: Add support for chaining event counters
Add support for 64bit event by using chained event counters
and 64bit cycle counters.

PMUv3 allows chaining a pair of adjacent 32-bit counters, effectively
forming a 64-bit counter. The low/even counter is programmed to count
the event of interest, and the high/odd counter is programmed to count
the CHAIN event, taken when the low/even counter overflows.

For CPU cycles, when 64bit mode is requested, the cycle counter
is used in 64bit mode. If the cycle counter is not available,
falls back to chaining.

Cc: Will Deacon <will.deacon@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-07-10 18:19:30 +01:00
Suzuki K Poulose 7dfc8db1d1 arm_pmu: Tidy up clear_event_idx call backs
The armpmu uses get_event_idx callback to allocate an event
counter for a given event, which marks the selected counter
as "used". Now, when we delete the counter, the arm_pmu goes
ahead and clears the "used" bit and then invokes the "clear_event_idx"
call back, which kind of splits the job between the core code
and the backend. To keep things tidy, mandate the implementation
of clear_event_idx() and add it for exisiting backends.
This will be useful for adding the chained event support, where
we leave the event idx maintenance to the backend.

Also, when an event is removed from the PMU, reset the hw.idx
to indicate that a counter is not allocated for this event,
to help the backends do better checks. This will be also used
for the chain counter support.

Cc: Will Deacon <will.deacon@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Julien Thierry <julien.thierry@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-07-10 18:19:02 +01:00
Suzuki K Poulose e2da97d328 arm_pmu: Add support for 64bit event counters
Each PMU has a set of 32bit event counters. But in some
special cases, the events could be counted using counters
which are effectively 64bit wide.

e.g, Arm V8 PMUv3 has a 64 bit cycle counter which can count
only the CPU cycles. Also, the PMU can chain the event counters
to effectively count as a 64bit counter.

Add support for tracking the events that uses 64bit counters.
This only affects the periods set for each counter in the core
driver.

Cc: Will Deacon <will.deacon@arm.com>
Reviewed-by: Julien Thierry <julien.thierry@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-07-10 18:19:02 +01:00
Suzuki K Poulose 8d3e994241 arm_pmu: Clean up maximum period handling
Each PMU defines their max_period of the counter as the maximum
value that can be counted. Since all the PMU backends support
32bit counters by default, let us remove the redundant field.

No functional changes.

Cc: Will Deacon <will.deacon@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Julien Thierry <julien.thierry@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-07-10 18:19:02 +01:00
Mark Rutland 0788f1e973 arm_pmu: simplify arm_pmu::handle_irq
The arm_pmu::handle_irq() callback has the same prototype as a generic
IRQ handler, taking the IRQ number and a void pointer argument which it
must convert to an arm_pmu pointer.

This means that all arm_pmu::handle_irq() take an IRQ number they never
use, and all must explicitly cast the void pointer to an arm_pmu
pointer.

Instead, let's change arm_pmu::handle_irq to take an arm_pmu pointer,
allowing these casts to be removed. The redundant IRQ number parameter
is also removed.

Suggested-by: Hoeun Ryu <hoeun.ryu@lge.com>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-05-21 18:07:05 +01:00
Ingo Molnar 134933e557 Linux 4.16-rc6
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Merge tag 'v4.16-rc6' into perf/core, to pick up fixes

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-19 20:37:35 +01:00
Peter Zijlstra edb39592a5 perf: Fix sibling iteration
Mark noticed that the change to sibling_list changed some iteration
semantics; because previously we used group_list as list entry,
sibling events would always have an empty sibling_list.

But because we now use sibling_list for both list head and list entry,
siblings will report as having siblings.

Fix this with a custom for_each_sibling_event() iterator.

Fixes: 8343aae661 ("perf/core: Remove perf_event::group_entry")
Reported-by: Mark Rutland <mark.rutland@arm.com>
Suggested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: vincent.weaver@maine.edu
Cc: alexander.shishkin@linux.intel.com
Cc: torvalds@linux-foundation.org
Cc: alexey.budankov@linux.intel.com
Cc: valery.cherepennikov@intel.com
Cc: eranian@google.com
Cc: acme@redhat.com
Cc: linux-tip-commits@vger.kernel.org
Cc: davidcc@google.com
Cc: kan.liang@intel.com
Cc: Dmitry.Prohorov@intel.com
Cc: jolsa@redhat.com
Link: https://lkml.kernel.org/r/20180315170129.GX4043@hirez.programming.kicks-ass.net
2018-03-16 20:44:12 +01:00
Peter Zijlstra 8343aae661 perf/core: Remove perf_event::group_entry
Now that all the grouping is done with RB trees, we no longer need
group_entry and can replace the whole thing with sibling_list.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Carrillo-Cisneros <davidcc@google.com>
Cc: Dmitri Prokhorov <Dmitry.Prohorov@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Valery Cherepennikov <valery.cherepennikov@intel.com>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-12 15:28:49 +01:00
Will Deacon b08e5fd90b arm_pmu: Use disable_irq_nosync when disabling SPI in CPU teardown hook
Commit 6de3f79112 ("arm_pmu: explicitly enable/disable SPIs at hotplug")
moved all of the arm_pmu IRQ enable/disable calls to the CPU hotplug hooks,
regardless of whether they are implemented as PPIs or SPIs. This can
lead to us sleeping from atomic context due to disable_irq blocking:

 | BUG: sleeping function called from invalid context at kernel/irq/manage.c:112
 | in_atomic(): 1, irqs_disabled(): 128, pid: 15, name: migration/1
 | no locks held by migration/1/15.
 | irq event stamp: 192
 | hardirqs last  enabled at (191): [<00000000803c2507>]
 | _raw_spin_unlock_irq+0x2c/0x4c
 | hardirqs last disabled at (192): [<000000007f57ad28>] multi_cpu_stop+0x9c/0x140
 | softirqs last  enabled at (0): [<0000000004ee1b58>]
 | copy_process.isra.77.part.78+0x43c/0x1504
 | softirqs last disabled at (0): [<          (null)>]           (null)
 | CPU: 1 PID: 15 Comm: migration/1 Not tainted 4.16.0-rc3-salvator-x #1651
 | Hardware name: Renesas Salvator-X board based on r8a7796 (DT)
 | Call trace:
 |  dump_backtrace+0x0/0x140
 |  show_stack+0x14/0x1c
 |  dump_stack+0xb4/0xf0
 |  ___might_sleep+0x1fc/0x218
 |  __might_sleep+0x70/0x80
 |  synchronize_irq+0x40/0xa8
 |  disable_irq+0x20/0x2c
 |  arm_perf_teardown_cpu+0x80/0xac

Since the interrupt is always CPU-affine and this code is running with
interrupts disabled, we can just use disable_irq_nosync as we know there
isn't a concurrent invocation of the handler to worry about.

Fixes: 6de3f79112 ("arm_pmu: explicitly enable/disable SPIs at hotplug")
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-02-28 14:59:47 +00:00
Mark Rutland 167e61438d arm_pmu: acpi: request IRQs up-front
We can't request IRQs in atomic context, so for ACPI systems we'll have
to request them up-front, and later associate them with CPUs.

This patch reorganises the arm_pmu code to do so. As we no longer have
the arm_pmu structure at probe time, a number of prototypes need to be
adjusted, requiring changes to the common arm_pmu code and arm_pmu
platform code.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-02-20 11:34:54 +00:00
Mark Rutland 84b4be57ae arm_pmu: note IRQs and PMUs per-cpu
To support ACPI systems, we need to request IRQs before we know the
associated PMU, and thus we need some percpu variable that the IRQ
handler can find the PMU from.

As we're going to request IRQs without the PMU, we can't rely on the
arm_pmu::active_irqs mask, and similarly need to track requested IRQs
with a percpu variable.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
[will: made armpmu_count_irq_users static]
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-02-20 11:34:54 +00:00
Mark Rutland 6de3f79112 arm_pmu: explicitly enable/disable SPIs at hotplug
To support ACPI systems, we need to request IRQs before CPUs are
hotplugged, and thus we need to request IRQs before we know their
associated PMU.

This is problematic if a PMU IRQ is pending out of reset, as it may be
taken before we know the PMU, and thus the IRQ handler won't be able to
handle it, leaving it screaming.

To avoid such problems, lets request all IRQs in a disabled state, and
explicitly enable/disable them at hotplug time, when we're sure the PMU
has been probed.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-02-20 11:34:54 +00:00
Mark Rutland 43fc9a2feb arm_pmu: acpi: check for mismatched PPIs
The arm_pmu platform code explicitly checks for mismatched PPIs at probe
time, while the ACPI code leaves this to the core code. Future
refactoring will make this difficult for the core code to check, so
let's have the ACPI code check this explicitly.

As before, upon a failure we'll continue on without an interrupt. Ho
hum.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-02-20 11:34:54 +00:00
Mark Rutland 0dc1a1851a arm_pmu: add armpmu_alloc_atomic()
In ACPI systems, we don't know the makeup of CPUs until we hotplug them
on, and thus have to allocate the PMU datastructures at hotplug time.
Thus, we must use GFP_ATOMIC allocations.

Let's add an armpmu_alloc_atomic() that we can use in this case.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-02-20 11:34:54 +00:00
Mark Rutland d3d5aac206 arm_pmu: fold platform helpers into platform code
The armpmu_{request,free}_irqs() helpers are only used by
arm_pmu_platform.c, so let's fold them in and make them static.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-02-20 11:34:53 +00:00
Mark Rutland c0248c9663 arm_pmu: kill arm_pmu_platdata
Now that we have no platforms passing platform data to the arm_pmu code,
we can get rid of the platdata and associated hooks, paving the way for
rework of our IRQ handling.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-02-20 11:34:53 +00:00
Julien Thierry 611479c79a arm/arm64: pmu: Distinguish percpu irq and percpu_devid irq
arm_pmu interrupts are maked as PERCPU even when these are not local
physical interrupts to a single CPU. When using non-local interrupts,
interrupts marked as PERCPU will not get freed not disabled properly
by the PMU driver.

Check if interrupts are local to a single CPU with PERCPU_DEVID since
this is what the PMU driver really needs to know.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Julien Thierry <julien.thierry@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-10-24 16:04:05 +01:00
Will Deacon 6c833bb924 arm64: perf: Allow standard PMUv3 events to be extended by the CPU type
Rather than continue adding CPU-specific event maps, instead look up by
default in the PMUv3 event map and only fallback to the CPU-specific maps
if either the event isn't described by PMUv3, or it is described but
the PMCEID registers say that it is unsupported by the current CPU.

Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-08-08 17:12:34 +01:00
Will Deacon a3287c41ff drivers/perf: arm_pmu: Request PMU SPIs with IRQF_PER_CPU
Since the PMU register interface is banked per CPU, CPU PMU interrrupts
cannot be handled by a CPU other than the one with the PMU asserting the
interrupt. This means that migrating PMU SPIs, as we do during a CPU
hotplug operation doesn't make any sense and can lead to the IRQ being
disabled entirely if we route a spurious IRQ to the new affinity target.

This has been observed in practice on AMD Seattle, where CPUs on the
non-boot cluster appear to take a spurious PMU IRQ when coming online,
which is routed to CPU0 where it cannot be handled.

This patch passes IRQF_PERCPU for PMU SPIs and forcefully sets their
affinity prior to requesting them, ensuring that they cannot
be migrated during hotplug events. This interacts badly with the DB8500
erratum workaround that ping-pongs the interrupt affinity from the handler,
so we avoid passing IRQF_PERCPU in that case by allowing the IRQ flags
to be overridden in the platdata.

Fixes: 3cf7ee98b8 ("drivers/perf: arm_pmu: move irq request/free into probe")
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-07-27 13:43:22 +01:00
Mark Rutland 45736a72fb drivers/perf: arm_pmu: add ACPI framework
This patch adds framework code to handle parsing PMU data out of the
MADT, sanity checking this, and managing the association of CPUs (and
their interrupts) with appropriate logical PMUs.

For the time being, we expect that only one PMU driver (PMUv3) will make
use of this, and we simply pass in a single probe function.

This is based on an earlier patch from Jeremy Linton.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Jeremy Linton <jeremy.linton@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-04-11 16:29:54 +01:00
Mark Rutland 18bfcfe51b drivers/perf: arm_pmu: split out platform device probe logic
Now that we've split the pdev and DT probing logic from the runtime
management, let's move the former into its own file. We gain a few lines
due to the copyright header and includes, but this should keep the logic
clearly separated, and paves the way for adding ACPI support in a
similar fashion.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Jeremy Linton <jeremy.linton@arm.com>
[will: rename nr_irqs to avoid conflict with global variable]
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-04-11 16:29:54 +01:00
Mark Rutland 3cf7ee98b8 drivers/perf: arm_pmu: move irq request/free into probe
Currently we request (and potentially free) all IRQs for a given PMU in
cpu_pmu_init(). This works for platform/DT probing today, but it doesn't
fit ACPI well as we don't have all our affinity data up-front.

In preparation for ACPI support, fold the IRQ request/free into
arm_pmu_device_probe(), which will remain specific to platform/DT
probing.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Jeremy Linton <jeremy.linton@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-04-11 16:29:53 +01:00
Mark Rutland 0e2663d921 drivers/perf: arm_pmu: split cpu-local irq request/free
Currently we have functions to request/free all IRQs for a given PMU.
While this works today, this won't work for ACPI, where we don't know
the full set of IRQs up front, and need to request them separately.

To enable supporting ACPI, this patch splits out the cpu-local
request/free into new functions, allowing us to request/free individual
IRQs.

As this makes it possible/necessary to request a PPI once per cpu, an
additional check is added to detect mismatched PPIs. This shouldn't
matter for the DT / platform case, as we check this when parsing.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Jeremy Linton <jeremy.linton@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-04-11 16:29:53 +01:00