Commit Graph

16 Commits

Author SHA1 Message Date
Mark Rutland fabdc0422c drivers/perf: pmuv3: don't expose SW_INCR event in sysfs
[ Upstream commit ca6f537e459e2da4b331fe8928d1a0b0f9301f42 ]

The SW_INCR event is somewhat unusual, and depends on the specific HW
counter that it is programmed into. When programmed into PMEVCNTR<n>,
SW_INCR will count any writes to PMSWINC_EL0 with bit n set, ignoring
writes to SW_INCR with bit n clear.

Event rotation means that there's no fixed relationship between
perf_events and HW counters, so this isn't all that useful.

Further, we program PMUSERENR.{SW,EN}=={0,0}, which causes EL0 writes to
PMSWINC_EL0 to be trapped and handled as UNDEFINED, resulting in a
SIGILL to userspace.

Given that, it's not a good idea to expose SW_INCR in sysfs. Hide it as
we did for CHAIN back in commit:

  4ba2578fa7 ("arm64: perf: don't expose CHAIN event in sysfs")

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20231204115847.2993026-1-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-02-05 20:14:14 +00:00
Ilkka Koskinen afadf1fad6 arm64/arm: arm_pmuv3: perf: Don't truncate 64-bit registers
[ Upstream commit 403edfa436286b21f5ffe6856ae5b36396e8966c ]

The driver used to truncate several 64-bit registers such as PMCEID[n]
registers used to describe whether architectural and microarchitectural
events in range 0x4000-0x401f exist. Due to discarding the bits, the
driver made the events invisible, even if they existed.

Moreover, PMCCFILTR and PMCR registers have additional bits in the upper
32 bits. This patch makes them available although they aren't currently
used. Finally, functions handling PMXEVCNTR and PMXEVTYPER registers are
removed as they not being used at all.

Fixes: df29ddf4f0 ("arm64: perf: Abstract system register accesses away")
Reported-by: Carl Worth <carl@os.amperecomputing.com>
Signed-off-by: Ilkka Koskinen <ilkka@os.amperecomputing.com>
Acked-by: Will Deacon <will@kernel.org>
Closes: https://lore.kernel.org/..
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Link: https://lore.kernel.org/r/20231102183012.1251410-1-ilkka@os.amperecomputing.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-11-20 11:59:38 +01:00
Linus Torvalds 0c02183427 ARM:
* Clean up vCPU targets, always returning generic v8 as the preferred target
 
 * Trap forwarding infrastructure for nested virtualization (used for traps
   that are taken from an L2 guest and are needed by the L1 hypervisor)
 
 * FEAT_TLBIRANGE support to only invalidate specific ranges of addresses
   when collapsing a table PTE to a block PTE.  This avoids that the guest
   refills the TLBs again for addresses that aren't covered by the table PTE.
 
 * Fix vPMU issues related to handling of PMUver.
 
 * Don't unnecessary align non-stack allocations in the EL2 VA space
 
 * Drop HCR_VIRT_EXCP_MASK, which was never used...
 
 * Don't use smp_processor_id() in kvm_arch_vcpu_load(),
   but the cpu parameter instead
 
 * Drop redundant call to kvm_set_pfn_accessed() in user_mem_abort()
 
 * Remove prototypes without implementations
 
 RISC-V:
 
 * Zba, Zbs, Zicntr, Zicsr, Zifencei, and Zihpm support for guest
 
 * Added ONE_REG interface for SATP mode
 
 * Added ONE_REG interface to enable/disable multiple ISA extensions
 
 * Improved error codes returned by ONE_REG interfaces
 
 * Added KVM_GET_REG_LIST ioctl() implementation for KVM RISC-V
 
 * Added get-reg-list selftest for KVM RISC-V
 
 s390:
 
 * PV crypto passthrough enablement (Tony, Steffen, Viktor, Janosch)
   Allows a PV guest to use crypto cards. Card access is governed by
   the firmware and once a crypto queue is "bound" to a PV VM every
   other entity (PV or not) looses access until it is not bound
   anymore. Enablement is done via flags when creating the PV VM.
 
 * Guest debug fixes (Ilya)
 
 x86:
 
 * Clean up KVM's handling of Intel architectural events
 
 * Intel bugfixes
 
 * Add support for SEV-ES DebugSwap, allowing SEV-ES guests to use debug
   registers and generate/handle #DBs
 
 * Clean up LBR virtualization code
 
 * Fix a bug where KVM fails to set the target pCPU during an IRTE update
 
 * Fix fatal bugs in SEV-ES intrahost migration
 
 * Fix a bug where the recent (architecturally correct) change to reinject
   #BP and skip INT3 broke SEV guests (can't decode INT3 to skip it)
 
 * Retry APIC map recalculation if a vCPU is added/enabled
 
 * Overhaul emergency reboot code to bring SVM up to par with VMX, tie the
   "emergency disabling" behavior to KVM actually being loaded, and move all of
   the logic within KVM
 
 * Fix user triggerable WARNs in SVM where KVM incorrectly assumes the TSC
   ratio MSR cannot diverge from the default when TSC scaling is disabled
   up related code
 
 * Add a framework to allow "caching" feature flags so that KVM can check if
   the guest can use a feature without needing to search guest CPUID
 
 * Rip out the ancient MMU_DEBUG crud and replace the useful bits with
   CONFIG_KVM_PROVE_MMU
 
 * Fix KVM's handling of !visible guest roots to avoid premature triple fault
   injection
 
 * Overhaul KVM's page-track APIs, and KVMGT's usage, to reduce the API surface
   that is needed by external users (currently only KVMGT), and fix a variety
   of issues in the process
 
 This last item had a silly one-character bug in the topic branch that
 was sent to me.  Because it caused pretty bad selftest failures in
 some configurations, I decided to squash in the fix.  So, while the
 exact commit ids haven't been in linux-next, the code has (from the
 kvm-x86 tree).
 
 Generic:
 
 * Wrap kvm_{gfn,hva}_range.pte in a union to allow mmu_notifier events to pass
   action specific data without needing to constantly update the main handlers.
 
 * Drop unused function declarations
 
 Selftests:
 
 * Add testcases to x86's sync_regs_test for detecting KVM TOCTOU bugs
 
 * Add support for printf() in guest code and covert all guest asserts to use
   printf-based reporting
 
 * Clean up the PMU event filter test and add new testcases
 
 * Include x86 selftests in the KVM x86 MAINTAINERS entry
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull kvm updates from Paolo Bonzini:
 "ARM:

   - Clean up vCPU targets, always returning generic v8 as the preferred
     target

   - Trap forwarding infrastructure for nested virtualization (used for
     traps that are taken from an L2 guest and are needed by the L1
     hypervisor)

   - FEAT_TLBIRANGE support to only invalidate specific ranges of
     addresses when collapsing a table PTE to a block PTE. This avoids
     that the guest refills the TLBs again for addresses that aren't
     covered by the table PTE.

   - Fix vPMU issues related to handling of PMUver.

   - Don't unnecessary align non-stack allocations in the EL2 VA space

   - Drop HCR_VIRT_EXCP_MASK, which was never used...

   - Don't use smp_processor_id() in kvm_arch_vcpu_load(), but the cpu
     parameter instead

   - Drop redundant call to kvm_set_pfn_accessed() in user_mem_abort()

   - Remove prototypes without implementations

  RISC-V:

   - Zba, Zbs, Zicntr, Zicsr, Zifencei, and Zihpm support for guest

   - Added ONE_REG interface for SATP mode

   - Added ONE_REG interface to enable/disable multiple ISA extensions

   - Improved error codes returned by ONE_REG interfaces

   - Added KVM_GET_REG_LIST ioctl() implementation for KVM RISC-V

   - Added get-reg-list selftest for KVM RISC-V

  s390:

   - PV crypto passthrough enablement (Tony, Steffen, Viktor, Janosch)

     Allows a PV guest to use crypto cards. Card access is governed by
     the firmware and once a crypto queue is "bound" to a PV VM every
     other entity (PV or not) looses access until it is not bound
     anymore. Enablement is done via flags when creating the PV VM.

   - Guest debug fixes (Ilya)

  x86:

   - Clean up KVM's handling of Intel architectural events

   - Intel bugfixes

   - Add support for SEV-ES DebugSwap, allowing SEV-ES guests to use
     debug registers and generate/handle #DBs

   - Clean up LBR virtualization code

   - Fix a bug where KVM fails to set the target pCPU during an IRTE
     update

   - Fix fatal bugs in SEV-ES intrahost migration

   - Fix a bug where the recent (architecturally correct) change to
     reinject #BP and skip INT3 broke SEV guests (can't decode INT3 to
     skip it)

   - Retry APIC map recalculation if a vCPU is added/enabled

   - Overhaul emergency reboot code to bring SVM up to par with VMX, tie
     the "emergency disabling" behavior to KVM actually being loaded,
     and move all of the logic within KVM

   - Fix user triggerable WARNs in SVM where KVM incorrectly assumes the
     TSC ratio MSR cannot diverge from the default when TSC scaling is
     disabled up related code

   - Add a framework to allow "caching" feature flags so that KVM can
     check if the guest can use a feature without needing to search
     guest CPUID

   - Rip out the ancient MMU_DEBUG crud and replace the useful bits with
     CONFIG_KVM_PROVE_MMU

   - Fix KVM's handling of !visible guest roots to avoid premature
     triple fault injection

   - Overhaul KVM's page-track APIs, and KVMGT's usage, to reduce the
     API surface that is needed by external users (currently only
     KVMGT), and fix a variety of issues in the process

  Generic:

   - Wrap kvm_{gfn,hva}_range.pte in a union to allow mmu_notifier
     events to pass action specific data without needing to constantly
     update the main handlers.

   - Drop unused function declarations

  Selftests:

   - Add testcases to x86's sync_regs_test for detecting KVM TOCTOU bugs

   - Add support for printf() in guest code and covert all guest asserts
     to use printf-based reporting

   - Clean up the PMU event filter test and add new testcases

   - Include x86 selftests in the KVM x86 MAINTAINERS entry"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (279 commits)
  KVM: x86/mmu: Include mmu.h in spte.h
  KVM: x86/mmu: Use dummy root, backed by zero page, for !visible guest roots
  KVM: x86/mmu: Disallow guest from using !visible slots for page tables
  KVM: x86/mmu: Harden TDP MMU iteration against root w/o shadow page
  KVM: x86/mmu: Harden new PGD against roots without shadow pages
  KVM: x86/mmu: Add helper to convert root hpa to shadow page
  drm/i915/gvt: Drop final dependencies on KVM internal details
  KVM: x86/mmu: Handle KVM bookkeeping in page-track APIs, not callers
  KVM: x86/mmu: Drop @slot param from exported/external page-track APIs
  KVM: x86/mmu: Bug the VM if write-tracking is used but not enabled
  KVM: x86/mmu: Assert that correct locks are held for page write-tracking
  KVM: x86/mmu: Rename page-track APIs to reflect the new reality
  KVM: x86/mmu: Drop infrastructure for multiple page-track modes
  KVM: x86/mmu: Use page-track notifiers iff there are external users
  KVM: x86/mmu: Move KVM-only page-track declarations to internal header
  KVM: x86: Remove the unused page-track hook track_flush_slot()
  drm/i915/gvt: switch from ->track_flush_slot() to ->track_remove_region()
  KVM: x86: Add a new page-track hook to handle memslot deletion
  drm/i915/gvt: Don't bother removing write-protection on to-be-deleted slot
  KVM: x86: Reject memslot MOVE operations if KVMGT is attached
  ...
2023-09-07 13:52:20 -07:00
Marc Zyngier b1f778a223 KVM: arm64: pmu: Resync EL0 state on counter rotation
Huang Shijie reports that, when profiling a guest from the host
with a number of events that exceeds the number of available
counters, the reported counts are wildly inaccurate. Without
the counter oversubscription, the reported counts are correct.

Their investigation indicates that upon counter rotation (which
takes place on the back of a timer interrupt), we fail to
re-apply the guest EL0 enabling, leading to the counting of host
events instead of guest events.

In order to solve this, add yet another hook between the host PMU
driver and KVM, re-applying the guest EL0 configuration if the
right conditions apply (the host is VHE, we are in interrupt
context, and we interrupted a running vcpu). This triggers a new
vcpu request which will apply the correct configuration on guest
reentry.

With this, we have the correct counts, even when the counters are
oversubscribed.

Reported-by: Huang Shijie <shijie@os.amperecomputing.com>
Suggested-by: Oliver Upton <oliver.upton@linux.dev>
Tested_by: Huang Shijie <shijie@os.amperecomputing.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20230809013953.7692-1-shijie@os.amperecomputing.com
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20230820090108.177817-1-maz@kernel.org
2023-08-22 13:35:51 +01:00
Anshuman Khandual 90d6867722 perf: pmuv3: Remove comments from armv8pmu_[enable|disable]_event()
The comments in armv8pmu_[enable|disable]_event() are blindingly obvious,
and does not contribute in making things any better. Let's drop them off.
Functional change is not intended.

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
Suggested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Link: https://lore.kernel.org/r/20230802090853.1190391-1-anshuman.khandual@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2023-08-04 17:23:57 +01:00
Rob Herring 989567fc0f perf: pmuv3: Add Cortex A520, A715, A720, X3 and X4 PMUs
Add support for the Arm Cortex-A520, Cortex-A715, Cortex-A720,
Cortex-X3, and Cortex-X4 CPU PMUs. They are straight-forward additions
with just new compatible strings.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20230706205505.308523-2-robh@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
2023-07-27 13:01:19 +01:00
Linus Torvalds 77b1a7f7a0 - Arnd Bergmann has fixed a bunch of -Wmissing-prototypes in
top-level directories.
 
 - Douglas Anderson has added a new "buddy" mode to the hardlockup
   detector.  It permits the detector to work on architectures which
   cannot provide the required interrupts, by having CPUs periodically
   perform checks on other CPUs.
 
 - Zhen Lei has enhanced kexec's ability to support two crash regions.
 
 - Petr Mladek has done a lot of cleanup on the hard lockup detector's
   Kconfig entries.
 
 - And the usual bunch of singleton patches in various places.
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Merge tag 'mm-nonmm-stable-2023-06-24-19-23' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull non-mm updates from Andrew Morton:

 - Arnd Bergmann has fixed a bunch of -Wmissing-prototypes in top-level
   directories

 - Douglas Anderson has added a new "buddy" mode to the hardlockup
   detector. It permits the detector to work on architectures which
   cannot provide the required interrupts, by having CPUs periodically
   perform checks on other CPUs

 - Zhen Lei has enhanced kexec's ability to support two crash regions

 - Petr Mladek has done a lot of cleanup on the hard lockup detector's
   Kconfig entries

 - And the usual bunch of singleton patches in various places

* tag 'mm-nonmm-stable-2023-06-24-19-23' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (72 commits)
  kernel/time/posix-stubs.c: remove duplicated include
  ocfs2: remove redundant assignment to variable bit_off
  watchdog/hardlockup: fix typo in config HARDLOCKUP_DETECTOR_PREFER_BUDDY
  powerpc: move arch_trigger_cpumask_backtrace from nmi.h to irq.h
  devres: show which resource was invalid in __devm_ioremap_resource()
  watchdog/hardlockup: define HARDLOCKUP_DETECTOR_ARCH
  watchdog/sparc64: define HARDLOCKUP_DETECTOR_SPARC64
  watchdog/hardlockup: make HAVE_NMI_WATCHDOG sparc64-specific
  watchdog/hardlockup: declare arch_touch_nmi_watchdog() only in linux/nmi.h
  watchdog/hardlockup: make the config checks more straightforward
  watchdog/hardlockup: sort hardlockup detector related config values a logical way
  watchdog/hardlockup: move SMP barriers from common code to buddy code
  watchdog/buddy: simplify the dependency for HARDLOCKUP_DETECTOR_PREFER_BUDDY
  watchdog/buddy: don't copy the cpumask in watchdog_next_cpu()
  watchdog/buddy: cleanup how watchdog_buddy_check_hardlockup() is called
  watchdog/hardlockup: remove softlockup comment in touch_nmi_watchdog()
  watchdog/hardlockup: in watchdog_hardlockup_check() use cpumask_copy()
  watchdog/hardlockup: don't use raw_cpu_ptr() in watchdog_hardlockup_kick()
  watchdog/hardlockup: HAVE_NMI_WATCHDOG must implement watchdog_hardlockup_probe()
  watchdog/hardlockup: keep kernel.nmi_watchdog sysctl as 0444 if probe fails
  ...
2023-06-28 10:59:38 -07:00
Douglas Anderson d7a0fe9ef6 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().  To cope with that, override
arch_perf_nmi_is_available() to let the watchdog framework know PMU not
ready, and inform the framework to re-initialize lockup detection once PMU
has been initialized.

[dianders@chromium.org: only HAVE_HARDLOCKUP_DETECTOR_PERF if the PMU config is enabled]
  Link: https://lkml.kernel.org/r/20230523073952.1.I60217a63acc35621e13f10be16c0cd7c363caf8c@changeid
Link: https://lkml.kernel.org/r/20230519101840.v5.18.Ia44852044cdcb074f387e80df6b45e892965d4a1@changeid
Co-developed-by: Sumit Garg <sumit.garg@linaro.org>
Signed-off-by: Sumit Garg <sumit.garg@linaro.org>
Co-developed-by: Pingfan Liu <kernelfans@gmail.com>
Signed-off-by: Pingfan Liu <kernelfans@gmail.com>
Signed-off-by: Lecopzer Chen <lecopzer.chen@mediatek.com>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chen-Yu Tsai <wens@csie.org>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Colin Cross <ccross@android.com>
Cc: Daniel Thompson <daniel.thompson@linaro.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Guenter Roeck <groeck@chromium.org>
Cc: Ian Rogers <irogers@google.com>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Masayoshi Mizuma <msys.mizuma@gmail.com>
Cc: Matthias Kaehlcke <mka@chromium.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: "Ravi V. Shankar" <ravi.v.shankar@intel.com>
Cc: Ricardo Neri <ricardo.neri@intel.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Stephen Boyd <swboyd@chromium.org>
Cc: Tzung-Bi Shih <tzungbi@chromium.org>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-09 17:44:22 -07:00
Reiji Watanabe 0c2f9acf6a KVM: arm64: PMU: Don't overwrite PMUSERENR with vcpu loaded
Currently, with VHE, KVM sets ER, CR, SW and EN bits of
PMUSERENR_EL0 to 1 on vcpu_load(), and saves and restores
the register value for the host on vcpu_load() and vcpu_put().
If the value of those bits are cleared on a pCPU with a vCPU
loaded (armv8pmu_start() would do that when PMU counters are
programmed for the guest), PMU access from the guest EL0 might
be trapped to the guest EL1 directly regardless of the current
PMUSERENR_EL0 value of the vCPU.

Fix this by not letting armv8pmu_start() overwrite PMUSERENR_EL0
on the pCPU where PMUSERENR_EL0 for the guest is loaded, and
instead updating the saved shadow register value for the host
so that the value can be restored on vcpu_put() later.
While vcpu_{put,load}() are manipulating PMUSERENR_EL0, disable
IRQs to prevent a race condition between these processes and IPIs
that attempt to update PMUSERENR_EL0 for the host EL0.

Suggested-by: Mark Rutland <mark.rutland@arm.com>
Suggested-by: Marc Zyngier <maz@kernel.org>
Fixes: 83a7a4d643 ("arm64: perf: Enable PMU counter userspace access for perf event")
Signed-off-by: Reiji Watanabe <reijiw@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20230603025035.3781797-3-reijiw@google.com
2023-06-04 17:19:36 +01:00
Stephane Eranian a30b87e6bd arm64: pmuv3: dynamically map PERF_COUNT_HW_BRANCH_INSTRUCTIONS
The mapping of perf_events generic hardware events to actual PMU events on
ARM PMUv3 may not always be correct. This is in particular true for the
PERF_COUNT_HW_BRANCH_INSTRUCTIONS event. Although the mapping points to an
architected event, it may not always be available. This can be seen with a
simple:

$ perf stat -e branches sleep 0
 Performance counter stats for 'sleep 0':

   <not supported>      branches

       0.001401081 seconds time elapsed

Yet the hardware does have an event that could be used for branches.

Dynamically check for a supported hardware event which can be used for
PERF_COUNT_HW_BRANCH_INSTRUCTIONS at mapping time.

And with that:

$ perf stat -e branches sleep 0

 Performance counter stats for 'sleep 0':

           166,739      branches

       0.000832163 seconds time elapsed

Co-developed-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Stephane Eranian <eranian@google.com>
Co-developed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Co-developed-by: Peter Newman <peternewman@google.com>
Signed-off-by: Peter Newman <peternewman@google.com>
Link: https://lore.kernel.org/all/YvunKCJHSXKz%2FkZB@FVFF77S0Q05N
Link: https://lore.kernel.org/r/20230411093809.657501-1-peternewman@google.com
Signed-off-by: Will Deacon <will@kernel.org>
2023-04-11 12:35:20 +01:00
Marc Zyngier 009d6dc87a ARM: perf: Allow the use of the PMUv3 driver on 32bit ARM
The only thing stopping the PMUv3 driver from compiling on 32bit
is the lack of defined system registers names and the handful of
required helpers.

This is easily solved by providing the sysreg accessors and updating
the Kconfig entry.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Co-developed-by: Zaid Al-Bassam <zalbassam@google.com>
Signed-off-by: Zaid Al-Bassam <zalbassam@google.com>
Tested-by: Florian Fainelli <f.fainelli@gmail.com>
Link: https://lore.kernel.org/r/20230317195027.3746949-8-zalbassam@google.com
Signed-off-by: Will Deacon <will@kernel.org>
2023-03-27 14:01:18 +01:00
Zaid Al-Bassam b3a070869f perf: pmuv3: Change GENMASK to GENMASK_ULL
GENMASK macro uses "unsigned long" (32-bit wide on arm and 64-bit
on arm64), This causes build issues when enabling PMUv3 on arm as
it tries to access bits > 31. This patch switches the GENMASK to
GENMASK_ULL, which uses "unsigned long long" (64-bit on both arm
and arm64).

Signed-off-by: Zaid Al-Bassam <zalbassam@google.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Tested-by: Florian Fainelli <f.fainelli@gmail.com>
Link: https://lore.kernel.org/r/20230317195027.3746949-6-zalbassam@google.com
Signed-off-by: Will Deacon <will@kernel.org>
2023-03-27 14:01:18 +01:00
Zaid Al-Bassam 11fba29a8a perf: pmuv3: Move inclusion of kvm_host.h to the arch-specific helper
KVM host support is available only on arm64.

By moving the inclusion of kvm_host.h to an arm64-specific file,
the 32bit architecture will be able to implement dummy helpers.

Signed-off-by: Zaid Al-Bassam <zalbassam@google.com>
Tested-by: Florian Fainelli <f.fainelli@gmail.com>
Link: https://lore.kernel.org/r/20230317195027.3746949-5-zalbassam@google.com
Signed-off-by: Will Deacon <will@kernel.org>
2023-03-27 14:01:18 +01:00
Zaid Al-Bassam 711432770f perf: pmuv3: Abstract PMU version checks
The current PMU version definitions are available for arm64 only,
As we want to add PMUv3 support to arm (32-bit), abstracts
these definitions by using arch-specific helpers.

Signed-off-by: Zaid Al-Bassam <zalbassam@google.com>
Tested-by: Florian Fainelli <f.fainelli@gmail.com>
Link: https://lore.kernel.org/r/20230317195027.3746949-4-zalbassam@google.com
Signed-off-by: Will Deacon <will@kernel.org>
2023-03-27 14:01:18 +01:00
Marc Zyngier df29ddf4f0 arm64: perf: Abstract system register accesses away
As we want to enable 32bit support, we need to distanciate the
PMUv3 driver from the AArch64 system register names.

This patch moves all system register accesses to an architecture
specific include file, allowing the 32bit counterpart to be
slotted in at a later time.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Co-developed-by: Zaid Al-Bassam <zalbassam@google.com>
Signed-off-by: Zaid Al-Bassam <zalbassam@google.com>
Tested-by: Florian Fainelli <f.fainelli@gmail.com>
Link: https://lore.kernel.org/r/20230317195027.3746949-3-zalbassam@google.com
Signed-off-by: Will Deacon <will@kernel.org>
2023-03-27 14:01:18 +01:00
Marc Zyngier 7755cec63a arm64: perf: Move PMUv3 driver to drivers/perf
Having the ARM PMUv3 driver sitting in arch/arm64/kernel is getting
in the way of being able to use perf on ARMv8 cores running a 32bit
kernel, such as 32bit KVM guests.

This patch moves it into drivers/perf/arm_pmuv3.c, with an include
file in include/linux/perf/arm_pmuv3.h. The only thing left in
arch/arm64 is some mundane perf stuff.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Zaid Al-Bassam <zalbassam@google.com>
Tested-by: Florian Fainelli <f.fainelli@gmail.com>
Link: https://lore.kernel.org/r/20230317195027.3746949-2-zalbassam@google.com
Signed-off-by: Will Deacon <will@kernel.org>
2023-03-27 14:01:18 +01:00