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>
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>
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>
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>
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>
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>
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>
