From: Andrew Murray <andrew.murray@arm.com>
To: Catalin Marinas <catalin.marinas@arm.com>,
Will Deacon <will@kernel.org>, Marc Zyngier <maz@kernel.org>,
Mark Rutland <mark.rutland@arm.com>
Cc: kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org
Subject: [PATCH v3 0/3] arm64: perf: Add support for ARMv8.5-PMU 64-bit counters
Date: Thu, 2 Jan 2020 12:39:02 +0000 [thread overview]
Message-ID: <20200102123905.29360-1-andrew.murray@arm.com> (raw)
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 add support for 64-bit event
counters.
As KVM doesn't yet support 64-bit event counters, we also trap
and emulate the Debug Feature Registers to limit the PMU version a
guest sees to PMUv3 for ARMv8.4.
Tested by running the following perf command on both guest and host
and ensuring that the figures are very similar:
perf stat -e armv8_pmuv3/inst_retired,long=1/ \
-e armv8_pmuv3/inst_retired,long=0/ -e cycles
Changes since v2:
- Rebased onto v5.5-rc4
- Mask 'cap' value to 'width' in cpuid_feature_cap_signed_field_width
Changes since v1:
- Rebased onto v5.5-rc1
Andrew Murray (3):
arm64: cpufeature: Extract capped fields
KVM: arm64: limit PMU version to ARMv8.4
arm64: perf: Add support for ARMv8.5-PMU 64-bit counters
arch/arm64/include/asm/cpufeature.h | 16 ++++++
arch/arm64/include/asm/perf_event.h | 3 +-
arch/arm64/include/asm/sysreg.h | 4 ++
arch/arm64/kernel/perf_event.c | 86 +++++++++++++++++++++++------
arch/arm64/kvm/sys_regs.c | 36 +++++++++++-
include/linux/perf/arm_pmu.h | 1 +
6 files changed, 126 insertions(+), 20 deletions(-)
--
2.21.0
_______________________________________________
kvmarm mailing list
kvmarm@lists.cs.columbia.edu
https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
next reply other threads:[~2020-01-02 12:39 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-01-02 12:39 Andrew Murray [this message]
2020-01-02 12:39 ` [PATCH v3 1/3] arm64: cpufeature: Extract capped fields Andrew Murray
2020-01-02 16:22 ` Suzuki Kuruppassery Poulose
2020-01-02 12:39 ` [PATCH v3 2/3] KVM: arm64: limit PMU version to ARMv8.4 Andrew Murray
2020-01-20 17:44 ` Will Deacon
2020-01-21 11:28 ` Andrew Murray
2020-01-20 17:55 ` Marc Zyngier
2020-01-21 9:04 ` Will Deacon
2020-01-21 11:18 ` Andrew Murray
2020-01-21 11:24 ` Andrew Murray
2020-01-02 12:39 ` [PATCH v3 3/3] arm64: perf: Add support for ARMv8.5-PMU 64-bit counters Andrew Murray
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20200102123905.29360-1-andrew.murray@arm.com \
--to=andrew.murray@arm.com \
--cc=catalin.marinas@arm.com \
--cc=kvmarm@lists.cs.columbia.edu \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=mark.rutland@arm.com \
--cc=maz@kernel.org \
--cc=will@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).