Hi all,
This RFC series adds support for the ARMv8.2 Statistical Profiling
Extension (SPE) to Linux in the form of a perf PMU driver. There aren't
any userspace patches for perf tool yet, but Kim (on CC) is working on
those and I thought posting the kernel side as an RFC was still worth it
in the meantime.
The series is structured as:
1-2: Tweak arm64 CPU feature detection to support heterogeneous
configurations where CPUs have differ in debug and profiling
capabilities.
3-4: Add EL2 SPE support (KVM world switch and initialisation)
5-6: Export some functions to modules, so this driver can be built as
a loadable module.
7-8: Introduce PERF_AUX_FLAG_COLLISION
9-10: Add the actual PMU driver and devicetree binding
Like intel-pt, the interface to the PMU is via the perf AUX area and the
profiling hardware writes directly to the pages mapped by userspace. The
hardware capabilities (caps/) and config field encodings (format/) are
advertised via sysfs.
Patches based on v4.10-rc2 and tested on an ARM FastModel.
Will
--->8
Will Deacon (10):
arm64: cpufeature: allow for version discrepancy in PMU
implementations
arm64: cpufeature: Don't enforce system-wide SPE capability
arm64: KVM: Save/restore the host SPE state when entering/leaving a VM
arm64: head.S: Enable EL1 (host) access to SPE when entered at EL2
genirq: export irq_get_percpu_devid_partition to modules
perf/core: Export AUX buffer helpers to modules
perf: Directly pass PERF_AUX_* flags to perf_aux_output_end
perf/core: Add PERF_AUX_FLAG_COLLISION to report colliding samples
drivers/perf: Add support for ARMv8.2 Statistical Profiling Extension
dt-bindings: Document devicetree binding for ARM SPE
Documentation/devicetree/bindings/arm/spe-pmu.txt | 20 +
arch/arm64/include/asm/kvm_arm.h | 3 +
arch/arm64/include/asm/kvm_host.h | 7 +-
arch/arm64/include/asm/sysreg.h | 1 +
arch/arm64/kernel/cpufeature.c | 9 +-
arch/arm64/kernel/head.S | 14 +-
arch/arm64/kvm/debug.c | 6 +
arch/arm64/kvm/hyp/debug-sr.c | 66 +-
arch/arm64/kvm/hyp/switch.c | 13 +-
arch/x86/events/intel/bts.c | 11 +-
arch/x86/events/intel/pt.c | 11 +-
drivers/hwtracing/coresight/coresight-etm-perf.c | 5 +-
drivers/perf/Kconfig | 8 +
drivers/perf/Makefile | 1 +
drivers/perf/arm_spe_pmu.c | 1247 +++++++++++++++++++++
include/linux/perf_event.h | 4 +-
include/uapi/linux/perf_event.h | 1 +
kernel/events/ring_buffer.c | 16 +-
kernel/irq/irqdesc.c | 1 +
19 files changed, 1416 insertions(+), 28 deletions(-)
create mode 100644 Documentation/devicetree/bindings/arm/spe-pmu.txt
create mode 100644 drivers/perf/arm_spe_pmu.c
--
2.1.4
