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Will Deacon 3da4390bcd arm64: perf: Don't register user access sysctl handler multiple times
Commit e201260081 ("arm64: perf: Add userspace counter access disable
switch") introduced a new 'perf_user_access' sysctl file to enable and
disable direct userspace access to the PMU counters. Sadly, Geert
reports that on his big.LITTLE SoC ('Renesas Salvator-XS w/ R-Car H3'),
the file is created for each PMU type probed, resulting in a splat
during boot:

  | hw perfevents: enabled with armv8_cortex_a53 PMU driver, 7 counters available
  | sysctl duplicate entry: /kernel//perf_user_access
  | CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.16.0-rc3-arm64-renesas-00003-ge2012600810c #1420
  | Hardware name: Renesas Salvator-X 2nd version board based on r8a77951 (DT)
  | Call trace:
  |  dump_backtrace+0x0/0x190
  |  show_stack+0x14/0x20
  |  dump_stack_lvl+0x88/0xb0
  |  dump_stack+0x14/0x2c
  |  __register_sysctl_table+0x384/0x818
  |  register_sysctl+0x20/0x28
  |  armv8_pmu_init.constprop.0+0x118/0x150
  |  armv8_a57_pmu_init+0x1c/0x28
  |  arm_pmu_device_probe+0x1b4/0x558
  |  armv8_pmu_device_probe+0x18/0x20
  |  platform_probe+0x64/0xd0
  |  hw perfevents: enabled with armv8_cortex_a57 PMU driver, 7 counters available

Introduce a state variable to track creation of the sysctl file and
ensure that it is only created once.

Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Fixes: e201260081 ("arm64: perf: Add userspace counter access disable switch")
Link: https://lore.kernel.org/r/CAMuHMdVcDxR9sGzc5pcnORiotonERBgc6dsXZXMd6wTvLGA9iw@mail.gmail.com
Signed-off-by: Will Deacon <will@kernel.org>
2022-01-04 14:57:14 +00:00
Will Deacon 1609c22a8a Merge branch 'for-next/perf-cpu' into for-next/perf
* for-next/perf-cpu:
  arm64: perf: Support new DT compatibles
  arm64: perf: Simplify registration boilerplate
  arm64: perf: Support Denver and Carmel PMUs
2021-12-14 18:13:25 +00:00
Robin Murphy 893c34b60a arm64: perf: Support new DT compatibles
Wire up the new DT compatibles so we can present appropriate
PMU names to userspace for the latest and greatest CPUs.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/62d14ba12d847ec7f1fba7cb0b3b881b437e1cc5.1639490264.git.robin.murphy@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2021-12-14 18:05:11 +00:00
Robin Murphy 6ac9f30bd4 arm64: perf: Simplify registration boilerplate
With the trend for per-core events moving to userspace JSON, registering
names for PMUv3 implementations is increasingly a pure boilerplate
exercise. Let's wrap things a step further so we can generate the basic
PMUv3 init function with a macro invocation, and reduce further new
addition to just 2 lines each.

Suggested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/b79477ea3b97f685d00511d4ecd2f686184dca34.1639490264.git.robin.murphy@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2021-12-14 18:05:11 +00:00
Thierry Reding d4c4844a9b arm64: perf: Support Denver and Carmel PMUs
Add support for the NVIDIA Denver and Carmel PMUs using the generic
PMUv3 event map for now.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
[ rm: reorder entries alphabetically ]
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/5f0f69d47acca78a9e479501aa4d8b429e23cf11.1639490264.git.robin.murphy@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2021-12-14 18:05:11 +00:00
Rob Herring 83a7a4d643 arm64: perf: Enable PMU counter userspace access for perf event
Arm PMUs can support direct userspace access of counters which allows for
low overhead (i.e. no syscall) self-monitoring of tasks. The same feature
exists on x86 called 'rdpmc'. Unlike x86, userspace access will only be
enabled for thread bound events. This could be extended if needed, but
simplifies the implementation and reduces the chances for any
information leaks (which the x86 implementation suffers from).

PMU EL0 access will be enabled when an event with userspace access is
part of the thread's context. This includes when the event is not
scheduled on the PMU. There's some additional overhead clearing
dirty counters when access is enabled in order to prevent leaking
disabled counter data from other tasks.

Unlike x86, enabling of userspace access must be requested with a new
attr bit: config1:1. If the user requests userspace access with 64-bit
counters, then the event open will fail if the h/w doesn't support
64-bit counters. Chaining is not supported with userspace access. The
modes for config1 are as follows:

config1 = 0 : user access disabled and always 32-bit
config1 = 1 : user access disabled and always 64-bit (using chaining if needed)
config1 = 2 : user access enabled and always 32-bit
config1 = 3 : user access enabled and always 64-bit

Based on work by Raphael Gault <raphael.gault@arm.com>, but has been
completely re-written.

Cc: Will Deacon <will@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-perf-users@vger.kernel.org
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20211208201124.310740-5-robh@kernel.org
[will: Made armv8pmu_proc_user_access_handler() static]
Signed-off-by: Will Deacon <will@kernel.org>
2021-12-14 11:40:59 +00:00
Rob Herring e201260081 arm64: perf: Add userspace counter access disable switch
Like x86, some users may want to disable userspace PMU counter
altogether. Add a sysctl 'perf_user_access' file to control userspace
counter access. The default is '0' which is disabled. Writing '1'
enables access.

Note that x86 supports globally enabling user access by writing '2' to
/sys/bus/event_source/devices/cpu/rdpmc. As there's not existing
userspace support to worry about, this shouldn't be necessary for Arm.
It could be added later if the need arises.

Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: linux-perf-users@vger.kernel.org
Acked-by: Will Deacon <will@kernel.org>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20211208201124.310740-4-robh@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
2021-12-14 11:30:54 +00:00
Anshuman Khandual fd264b3105 arm64/perf: Replace '0xf' instances with ID_AA64DFR0_PMUVER_IMP_DEF
ID_AA64DFR0_PMUVER_IMP_DEF, indicating an "implementation defined" PMU,
never actually gets used although there are '0xf' instances scattered
all around. Use the symbolic name instead of the raw hex constant.

Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Link: https://lore.kernel.org/r/1628652427-24695-2-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2021-08-11 11:02:12 +01:00
Qi Liu 64432f0906 arm64: perf: Simplify EVENT ATTR macro in perf_event.c
Use common macro PMU_EVENT_ATTR_ID to simplify ARMV8_EVENT_ATTR

Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Qi Liu <liuqi115@huawei.com>
Link: https://lore.kernel.org/r/1623220863-58233-8-git-send-email-liuqi115@huawei.com
Signed-off-by: Will Deacon <will@kernel.org>
2021-06-11 11:18:41 +01:00
Shaokun Zhang 281e44f5fd arm64: perf: Add more support on caps under sysfs
Armv8.7 has introduced BUS_SLOTS and BUS_WIDTH in PMMIR_EL1 register,
add two entries in caps for bus_slots and bus_width under sysfs. It
will return the true slots and width if the information is available,
otherwise it will return 0.

Cc: Will Deacon <will@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Shaokun Zhang <zhangshaokun@hisilicon.com>
Link: https://lore.kernel.org/r/1622704502-63951-1-git-send-email-zhangshaokun@hisilicon.com
Signed-off-by: Will Deacon <will@kernel.org>
2021-06-03 09:53:17 +01:00
Tian Tao a5740e9555 arm64: perf: Convert snprintf to sysfs_emit
Use sysfs_emit instead of snprintf to avoid buf overrun,because in
sysfs_emit it strictly checks whether buf is null or buf whether
pagesize aligned, otherwise it returns an error.

Signed-off-by: Tian Tao <tiantao6@hisilicon.com>
Link: https://lore.kernel.org/r/1621497585-30887-1-git-send-email-tiantao6@hisilicon.com
Signed-off-by: Will Deacon <will@kernel.org>
2021-06-01 14:18:23 +01:00
Qi Liu 2c2e21e78a arm64: perf: Remove redundant initialization in perf_event.c
The initialization of value in function armv8pmu_read_hw_counter()
and armv8pmu_read_counter() seem redundant, as they are soon updated.
So, We can remove them.

Signed-off-by: Qi Liu <liuqi115@huawei.com>
Link: https://lore.kernel.org/r/1617275801-1980-1-git-send-email-liuqi115@huawei.com
Signed-off-by: Will Deacon <will@kernel.org>
2021-04-01 18:05:32 +01:00
Rob Herring 7bb8bc6eb5 arm64: perf: Fix 64-bit event counter read truncation
Commit 0fdf1bb759 ("arm64: perf: Avoid PMXEV* indirection") changed
armv8pmu_read_evcntr() to return a u32 instead of u64. The result is
silent truncation of the event counter when using 64-bit counters. Given
the offending commit appears to have passed thru several folks, it seems
likely this was a bad rebase after v8.5 PMU 64-bit counters landed.

Cc: Alexandru Elisei <alexandru.elisei@arm.com>
Cc: Julien Thierry <julien.thierry.kdev@gmail.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: <stable@vger.kernel.org>
Fixes: 0fdf1bb759 ("arm64: perf: Avoid PMXEV* indirection")
Signed-off-by: Rob Herring <robh@kernel.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Alexandru Elisei <alexandru.elisei@arm.com>
Link: https://lore.kernel.org/r/20210310004412.1450128-1-robh@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
2021-03-10 11:08:23 +00:00
Will Deacon c974a8e574 Merge branch 'for-next/perf' into for-next/core
Perf and PMU updates including support for Cortex-A78 and the v8.3 SPE
extensions.

* for-next/perf:
  drivers/perf: Replace spin_lock_irqsave to spin_lock
  dt-bindings: arm: add Cortex-A78 binding
  arm64: perf: add support for Cortex-A78
  arm64: perf: Constify static attribute_group structs
  drivers/perf: Prevent forced unbinding of ARM_DMC620_PMU drivers
  perf/arm-cmn: Move IRQs when migrating context
  perf/arm-cmn: Fix PMU instance naming
  perf: Constify static struct attribute_group
  perf: hisi: Constify static struct attribute_group
  perf/imx_ddr: Constify static struct attribute_group
  perf: qcom: Constify static struct attribute_group
  drivers/perf: Add support for ARMv8.3-SPE
2021-02-12 15:09:34 +00:00
Zhiyuan Dai d9f1b52afa arm64: improve whitespace
In a few places we don't have whitespace between macro parameters,
which makes them hard to read. This patch adds whitespace to clearly
separate the parameters.

In a few places we have unnecessary whitespace around unary operators,
which is confusing, This patch removes the unnecessary whitespace.

Signed-off-by: Zhiyuan Dai <daizhiyuan@phytium.com.cn>
Link: https://lore.kernel.org/r/1612403029-5011-1-git-send-email-daizhiyuan@phytium.com.cn
Signed-off-by: Will Deacon <will@kernel.org>
2021-02-04 13:59:49 +00:00
Seiya Wang db2bb91f2e arm64: perf: add support for Cortex-A78
Add support for Cortex-A78 using generic PMUv3 for now.

Signed-off-by: Seiya Wang <seiya.wang@mediatek.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20210203055348.4935-2-seiya.wang@mediatek.com
Signed-off-by: Will Deacon <will@kernel.org>
2021-02-03 20:42:54 +00:00
Rikard Falkeborn 2ceee7ed4c arm64: perf: Constify static attribute_group structs
The only usage of these is to put their addresses in an array of
pointers to const attribute_group structs. Make them const to allow the
compiler to put them in read-only memory.

Signed-off-by: Rikard Falkeborn <rikard.falkeborn@gmail.com>
Signed-off-by: Will Deacon <will@kernel.org>
2021-02-02 18:46:05 +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 05ab728133 arm64: perf: Defer irq_work to IPI_IRQ_WORK
When handling events, armv8pmu_handle_irq() calls perf_event_overflow(),
and subsequently calls irq_work_run() to handle any work queued by
perf_event_overflow(). As perf_event_overflow() raises IPI_IRQ_WORK when
queuing the work, this isn't strictly necessary and the work could be
handled as part of the IPI_IRQ_WORK handler.

In the common case the IPI handler will run immediately after the PMU IRQ
handler, and where the PE is heavily loaded with interrupts other handlers
may run first, widening the window where some counters are disabled.

In practice this window is unlikely to be a significant issue, and removing
the call to irq_work_run() would make the PMU IRQ handler NMI safe in
addition to making it simpler, so let's do that.

[Alexandru E.: Reworded commit message]

Signed-off-by: Julien Thierry <julien.thierry@arm.com>
Signed-off-by: Alexandru Elisei <alexandru.elisei@arm.com>
Cc: Julien Thierry <julien.thierry.kdev@gmail.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20200924110706.254996-5-alexandru.elisei@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2020-09-28 19:00:17 +01:00
Julien Thierry 2a0e2a02e4 arm64: perf: Remove PMU locking
The PMU is disabled and enabled, and the counters are programmed from
contexts where interrupts or preemption is disabled.

The functions to toggle the PMU and to program the PMU counters access the
registers directly and don't access data modified by the interrupt handler.
That, and the fact that they're always called from non-preemptible
contexts, means that we don't need to disable interrupts or use a spinlock.

[Alexandru E.: Explained why locking is not needed, removed WARN_ONs]

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: Will Deacon <will.deacon@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20200924110706.254996-4-alexandru.elisei@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2020-09-28 19:00:17 +01:00
Mark Rutland 0fdf1bb759 arm64: perf: Avoid PMXEV* indirection
Currently we access the counter registers and their respective type
registers indirectly. This requires us to write to PMSELR, issue an ISB,
then access the relevant PMXEV* registers.

This is unfortunate, because:

* Under virtualization, accessing one register requires two traps to
  the hypervisor, even though we could access the register directly with
  a single trap.

* We have to issue an ISB which we could otherwise avoid the cost of.

* When we use NMIs, the NMI handler will have to save/restore the select
  register in case the code it preempted was attempting to access a
  counter or its type register.

We can avoid these issues by directly accessing the relevant registers.
This patch adds helpers to do so.

In armv8pmu_enable_event() we still need the ISB to prevent the PE from
reordering the write to PMINTENSET_EL1 register. If the interrupt is
enabled before we disable the counter and the new event is configured,
we might get an interrupt triggered by the previously programmed event
overflowing, but which we wrongly attribute to the event that we are
enabling. Execute an ISB after we disable the counter.

In the process, remove the comment that refers to the ARMv7 PMU.

[Julien T.: Don't inline read/write functions to avoid big code-size
	increase, remove unused read_pmevtypern function,
	fix counter index issue.]
[Alexandru E.: Removed comment, removed trailing semicolons in macros,
	added ISB]

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
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: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20200924110706.254996-3-alexandru.elisei@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2020-09-28 19:00:17 +01:00
Alexandru Elisei 490d7b7c08 arm64: perf: Add missing ISB in armv8pmu_enable_counter()
Writes to the PMXEVTYPER_EL0 register are not self-synchronising. In
armv8pmu_enable_event(), the PE can reorder configuring the event type
after we have enabled the counter and the interrupt. This can lead to an
interrupt being asserted because of the previous event type that we were
counting using the same counter, not the one that we've just configured.

The same rationale applies to writes to the PMINTENSET_EL1 register. The PE
can reorder enabling the interrupt at any point in the future after we have
enabled the event.

Prevent both situations from happening by adding an ISB just before we
enable the event counter.

Fixes: 030896885a ("arm64: Performance counters support")
Reported-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>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20200924110706.254996-2-alexandru.elisei@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2020-09-28 19:00:16 +01:00
Shaokun Zhang f5be3a61fd arm64: perf: Add support caps under sysfs
ARMv8.4-PMU introduces the PMMIR_EL1 registers and some new PMU events,
like STALL_SLOT etc, are related to it. Let's add a caps directory to
/sys/bus/event_source/devices/armv8_pmuv3_0/ and support slots from
PMMIR_EL1 registers in this entry. The user programs can get the slots
from sysfs directly.

/sys/bus/event_source/devices/armv8_pmuv3_0/caps/slots is exposed
under sysfs. Both ARMv8.4-PMU and STALL_SLOT event are implemented,
it returns the slots from PMMIR_EL1, otherwise it will return 0.

Signed-off-by: Shaokun Zhang <zhangshaokun@hisilicon.com>
Cc: Will Deacon <will@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/1600754025-53535-1-git-send-email-zhangshaokun@hisilicon.com
Signed-off-by: Will Deacon <will@kernel.org>
2020-09-28 14:53:45 +01:00
Qi Liu 44fdf4ed26 arm64: perf: Remove unnecessary event_idx check
event_idx is obtained from armv8pmu_get_event_idx(), and this idx must be
between ARMV8_IDX_CYCLE_COUNTER and cpu_pmu->num_events. So it's unnecessary
to do this check. Let's remove it.

Signed-off-by: Qi Liu <liuqi115@huawei.com>
Link: https://lore.kernel.org/r/1599213458-28394-1-git-send-email-liuqi115@huawei.com
Signed-off-by: Will Deacon <will@kernel.org>
2020-09-07 18:35:39 +01:00
Leo Yan ffdbd3d835 arm64: perf: Add general hardware LLC events for PMUv3
This patch is to add the general hardware last level cache (LLC) events
for PMUv3: one event is for LLC access and another is for LLC miss.

With this change, perf tool can support last level cache profiling,
below is an example to demonstrate the usage on Arm64:

  $ perf stat -e LLC-load-misses -e LLC-loads -- \
	  perf bench mem memcpy -s 1024MB -l 100 -f default

  [...]

    Performance counter stats for 'perf bench mem memcpy -s 1024MB -l 100 -f default':

        35,534,262      LLC-load-misses           #    2.16% of all LL-cache hits
     1,643,946,443      LLC-loads

  [...]

Signed-off-by: Leo Yan <leo.yan@linaro.org>
Link: https://lore.kernel.org/r/20200811053505.21223-1-leo.yan@linaro.org
Signed-off-by: Will Deacon <will@kernel.org>
2020-09-07 11:42:38 +01:00
Shaokun Zhang 55fdc1f44c arm64: perf: Expose some new events via sysfs
Some new PMU events can been detected by PMCEID1_EL0, but it can't
be listed, Let's expose these through sysfs.

Signed-off-by: Shaokun Zhang <zhangshaokun@hisilicon.com>
Cc: Will Deacon <will@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/1595328573-12751-2-git-send-email-zhangshaokun@hisilicon.com
Signed-off-by: Will Deacon <will@kernel.org>
2020-07-21 12:59:42 +01:00
Peter Zijlstra c8f9eb0d6e arm64: perf: Add cap_user_time_short
This completes the ARM64 cap_user_time support.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Leo Yan <leo.yan@linaro.org>
Link: https://lore.kernel.org/r/20200716051130.4359-7-leo.yan@linaro.org
Signed-off-by: Will Deacon <will@kernel.org>
2020-07-20 11:50:47 +01:00
Peter Zijlstra 279a811eb5 arm64: perf: Only advertise cap_user_time for arch_timer
When sched_clock is running on anything other than arch_timer, don't
advertise cap_user_time*.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Leo Yan <leo.yan@linaro.org>
Link: https://lore.kernel.org/r/20200716051130.4359-5-leo.yan@linaro.org
Requested-by: Will Deacon <will@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
2020-07-20 11:50:47 +01:00
Peter Zijlstra 950b74ddef arm64: perf: Implement correct cap_user_time
As reported by Leo; the existing implementation is broken when the
clock and counter don't intersect at 0.

Use the sched_clock's struct clock_read_data information to correctly
implement cap_user_time and cap_user_time_zero.

Note that the ARM64 counter is architecturally only guaranteed to be
56bit wide (implementations are allowed to be wider) and the existing
perf ABI cannot deal with wrap-around.

This implementation should also be faster than the old; seeing how we
don't need to recompute mult and shift all the time.

[leoyan: Use mul_u64_u32_shr() to convert cyc to ns to avoid overflow]

Reported-by: Leo Yan <leo.yan@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Leo Yan <leo.yan@linaro.org>
Link: https://lore.kernel.org/r/20200716051130.4359-4-leo.yan@linaro.org
Signed-off-by: Will Deacon <will@kernel.org>
2020-07-20 11:50:47 +01:00
Shaokun Zhang 539707caa1 arm64: perf: Correct the event index in sysfs
When PMU event ID is equal or greater than 0x4000, it will be reduced
by 0x4000 and it is not the raw number in the sysfs. Let's correct it
and obtain the raw event ID.

Before this patch:
cat /sys/bus/event_source/devices/armv8_pmuv3_0/events/sample_feed
event=0x001
After this patch:
cat /sys/bus/event_source/devices/armv8_pmuv3_0/events/sample_feed
event=0x4001

Signed-off-by: Shaokun Zhang <zhangshaokun@hisilicon.com>
Cc: Will Deacon <will@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/1592487344-30555-3-git-send-email-zhangshaokun@hisilicon.com
[will: fixed formatting of 'if' condition]
Signed-off-by: Will Deacon <will@kernel.org>
2020-07-20 11:24:08 +01:00
Andrew Murray 8673e02e58 arm64: perf: Add support for ARMv8.5-PMU 64-bit counters
At present ARMv8 event counters are limited to 32-bits, though by
using the CHAIN event it's possible to combine adjacent counters to
achieve 64-bits. The perf config1:0 bit can be set to use such a
configuration.

With the introduction of ARMv8.5-PMU support, all event counters can
now be used as 64-bit counters.

Let's enable 64-bit event counters where support exists. Unless the
user sets config1:0 we will adjust the counter value such that it
overflows upon 32-bit overflow. This follows the same behaviour as
the cycle counter which has always been (and remains) 64-bits.

Signed-off-by: Andrew Murray <andrew.murray@arm.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
[Mark: fix ID field names, compare with 8.5 value]
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
2020-03-17 22:50:30 +00:00
Robin Murphy 29227d6ea1 arm64: perf: Clean up enable/disable calls
Reading this code bordered on painful, what with all the repetition and
pointless return values. More fundamentally, dribbling the hardware
enables and disables in one bit at a time incurs needless system
register overhead for chained events and on reset. We already use
bitmask values for the KVM hooks, so consolidate all the register
accesses to match, and make a reasonable saving in both source and
object code.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
2020-03-17 22:45:59 +00:00
Robin Murphy 29cc4ceeac arm64: perf: Support new DT compatibles
Add support for matching the new PMUs. For now, this just wires them up
as generic PMUv3 such that people writing DTs for new SoCs can do the
right thing, and at least have architectural and raw events be usable.
We can come back and fill in event maps for sysfs and/or perf tools at
a later date.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
2020-03-02 11:54:18 +00:00
Robin Murphy e424b17985 arm64: perf: Refactor PMU init callbacks
The PMU init callbacks are already drowning in boilerplate, so before
doubling the number of supported PMU models, give it a sensible refactor
to significantly reduce the bloat, both in source and object code.
Although nobody uses non-default sysfs attributes today, there's minimal
impact to preserving the notion that maybe, some day, somebody might, so
we may as well keep up appearances.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
2020-03-02 11:54:06 +00:00
Shaokun Zhang 9ef8567ccf arm64: perf: Simplify the ARMv8 PMUv3 event attributes
For each PMU event, there is a ARMV8_EVENT_ATTR(xx, XX) and
&armv8_event_attr_xx.attr.attr. Let's redefine the ARMV8_EVENT_ATTR
to simplify the armv8_pmuv3_event_attrs.

Cc: Will Deacon <will@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Shaokun Zhang <zhangshaokun@hisilicon.com>
[will: Dropped unnecessary array syntax]
Signed-off-by: Will Deacon <will@kernel.org>
2019-11-01 14:51:19 +00:00
Raphael Gault d91cc2f46a arm64: perf_event: Add missing header needed for smp_processor_id()
In perf_event.c we use smp_processor_id(), but we haven't included
<linux/smp.h> where it is defined, and rely on this being pulled in
via a transitive include. Let's make this more robust by including
<linux.smp.h> explicitly.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Raphael Gault <raphael.gault@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
2019-08-20 17:10:05 +01:00
Shaokun Zhang ca786b8db7 arm64: perf: Remove unused macro
ARMV8_EVENT_ATTR_RESOLVE became unused after commit <4b1a9e6934ec>
("arm64/perf: Filter common events based on PMCEIDn_EL0").

Remove it.

Cc: Will Deacon <will@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Shaokun Zhang <zhangshaokun@hisilicon.com>
Signed-off-by: Will Deacon <will@kernel.org>
2019-07-23 17:18:28 +01:00
Thomas Gleixner caab277b1d treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234
Based on 1 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
  distributed in the hope that 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 you should have received a copy of the gnu general
  public license along with this program if not see http www gnu org
  licenses

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 503 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Enrico Weigelt <info@metux.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190602204653.811534538@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-19 17:09:07 +02:00
Linus Torvalds 0ef0fd3515 * 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
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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:
   - 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
  ...
2019-05-17 10:33:30 -07:00
Andrew Murray 435e53fb5e arm64: KVM: Enable VHE support for :G/:H perf event modifiers
With VHE different exception levels are used between the host (EL2) and
guest (EL1) with a shared exception level for userpace (EL0). We can take
advantage of this and use the PMU's exception level filtering to avoid
enabling/disabling counters in the world-switch code. Instead we just
modify the counter type to include or exclude EL0 at vcpu_{load,put} time.

We also ensure that trapped PMU system register writes do not re-enable
EL0 when reconfiguring the backing perf events.

This approach completely avoids blackout windows seen with !VHE.

Suggested-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Andrew Murray <andrew.murray@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-04-24 15:46:26 +01:00
Andrew Murray d1947bc4bc arm64: arm_pmu: Add !VHE support for exclude_host/exclude_guest attributes
Add support for the :G and :H attributes in perf by handling the
exclude_host/exclude_guest event attributes.

We notify KVM of counters that we wish to be enabled or disabled on
guest entry/exit and thus defer from starting or stopping events based
on their event attributes.

With !VHE we switch the counters between host/guest at EL2. We are able
to eliminate counters counting host events on the boundaries of guest
entry/exit when using :G by filtering out EL2 for exclude_host. When
using !exclude_hv there is a small blackout window at the guest
entry/exit where host events are not captured.

Signed-off-by: Andrew Murray <andrew.murray@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-04-24 15:35:58 +01:00
Andrew Murray 21bb0ebf5d arm64: arm_pmu: Remove unnecessary isb instruction
The armv8pmu_enable_event_counter function issues an isb instruction
after enabling a pair of counters - this doesn't provide any value
and is inconsistent with the armv8pmu_disable_event_counter.

In any case armv8pmu_enable_event_counter is always called with the
PMU stopped. Starting the PMU with armv8pmu_start results in an isb
instruction being issued prior to writing to PMCR_EL0.

Let's remove the unnecessary isb instruction.

Signed-off-by: Andrew Murray <andrew.murray@arm.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-04-24 15:34:31 +01:00
Raphael Gault 3d659e7d65 arm64: perf_event: Remove wrongfully used inline
The functions armv8pmu_read_counter() and armv8pmu_write_counter()
are `static inline` while they are only referenced when assigned
to a function pointer field in a `struct arm_pmu` instance.

The inline keyword is thus counter intuitive and shouldn't be used.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Raphael Gault <raphael.gault@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-11 18:12:42 +01:00
Andrew Murray b36506787c arm64: perf: remove misleading comment
The comment for the armv8pmu_set_event_filter function suggests that
it only works for PMUv2 PMUs - this is incorrect.

Let's remove the incorrect comment.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Andrew Murray <andrew.murray@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-01-19 22:57:38 +00:00
Anders Roxell 81e9fa8bab arm64: perf: set suppress_bind_attrs flag to true
The armv8_pmuv3 driver doesn't have a remove function, and when the test
'CONFIG_DEBUG_TEST_DRIVER_REMOVE=y' is enabled, the following Call trace
can be seen.

[    1.424287] Failed to register pmu: armv8_pmuv3, reason -17
[    1.424870] WARNING: CPU: 0 PID: 1 at ../kernel/events/core.c:11771 perf_event_sysfs_init+0x98/0xdc
[    1.425220] Modules linked in:
[    1.425531] CPU: 0 PID: 1 Comm: swapper/0 Tainted: G        W         4.19.0-rc7-next-20181012-00003-ge7a97b1ad77b-dirty #35
[    1.425951] Hardware name: linux,dummy-virt (DT)
[    1.426212] pstate: 80000005 (Nzcv daif -PAN -UAO)
[    1.426458] pc : perf_event_sysfs_init+0x98/0xdc
[    1.426720] lr : perf_event_sysfs_init+0x98/0xdc
[    1.426908] sp : ffff00000804bd50
[    1.427077] x29: ffff00000804bd50 x28: ffff00000934e078
[    1.427429] x27: ffff000009546000 x26: 0000000000000007
[    1.427757] x25: ffff000009280710 x24: 00000000ffffffef
[    1.428086] x23: ffff000009408000 x22: 0000000000000000
[    1.428415] x21: ffff000009136008 x20: ffff000009408730
[    1.428744] x19: ffff80007b20b400 x18: 000000000000000a
[    1.429075] x17: 0000000000000000 x16: 0000000000000000
[    1.429418] x15: 0000000000000400 x14: 2e79726f74636572
[    1.429748] x13: 696420656d617320 x12: 656874206e692065
[    1.430060] x11: 6d616e20656d6173 x10: 2065687420687469
[    1.430335] x9 : ffff00000804bd50 x8 : 206e6f7361657220
[    1.430610] x7 : 2c3376756d705f38 x6 : ffff00000954d7ce
[    1.430880] x5 : 0000000000000000 x4 : 0000000000000000
[    1.431226] x3 : 0000000000000000 x2 : ffffffffffffffff
[    1.431554] x1 : 4d151327adc50b00 x0 : 0000000000000000
[    1.431868] Call trace:
[    1.432102]  perf_event_sysfs_init+0x98/0xdc
[    1.432382]  do_one_initcall+0x6c/0x1a8
[    1.432637]  kernel_init_freeable+0x1bc/0x280
[    1.432905]  kernel_init+0x18/0x160
[    1.433115]  ret_from_fork+0x10/0x18
[    1.433297] ---[ end trace 27fd415390eb9883 ]---

Rework to set suppress_bind_attrs flag to avoid removing the device when
CONFIG_DEBUG_TEST_DRIVER_REMOVE=y, since there's no real reason to
remove the armv8_pmuv3 driver.

Cc: Arnd Bergmann <arnd@arndb.de>
Co-developed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-11-21 13:16:34 +00:00
Shaokun Zhang e2b5c5c7de arm64: perf: Fix typos in comment
Fix up one typos: Onl -> Only

Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Shaokun Zhang <zhangshaokun@hisilicon.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-11-21 13:16:34 +00:00
Will Deacon 2ddd5e5825 arm64: perf: Hook up new events
There have been some additional events added to the PMU architecture
since Armv8.0, so expose them via our sysfs infrastructure.

Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-11-21 13:16:34 +00:00
Will Deacon 4b47e573a4 arm64: perf: Move event definitions into perf_event.h
The PMU event numbers are split between perf_event.h and perf_event.c,
which makes it difficult to spot any gaps in the numbers which may be
allocated in the future.

This patch sorts the events numerically, adds some missing events and
moves the definitions into perf_event.h.

Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-11-21 13:16:34 +00:00
Will Deacon cf7175ece0 arm64: perf: Remove duplicate generic cache events
We cannot distinguish reads from writes in our generic cache events, so
drop the WRITE entries and leave the READ entries pointing to the combined
read/write events, as is done by other CPUs and architectures.

Reported-by: Ganapatrao Kulkarni <Ganapatrao.Kulkarni@cavium.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-11-21 13:16:33 +00:00