[PATCH V2 0/8] perf: Expand perf_branch_entry
Anshuman Khandual
anshuman.khandual at arm.com
Tue Mar 8 19:36:34 PST 2022
Branch Record Buffer Extension (BRBE) implementation on arm64 captures more
branch type classification which cannot be accommodated in the current perf
branch record format via perf_branch_entry.type element (4 bit field). Also
it captures privilege information which does not have a corresponding slot
in perf_branch_entry. This series expands struct perf_branch_entry, to meet
both these requirements without breaking the existing user space ABI for
perf tools.
All architecture specific branch types added via perf_branch_entry.new_type
field in [PATCH 3/4] will be used in BRBE implementation on arm64 platform
later on with the following map.
#ifdef CONFIG_ARM64
#define PERF_BR_FIQ PERF_BR_NEW_ARCH_1
#define PERF_BR_DEBUG_HALT PERF_BR_NEW_ARCH_2
#define PERF_BR_DEBUG_EXIT PERF_BR_NEW_ARCH_3
#define PERF_BR_DEBUG_INST PERF_BR_NEW_ARCH_4
#define PERF_BR_DEBUG_DATA PERF_BR_NEW_ARCH_5
#endif
This actually combines following patches and series into a single series.
- https://lore.kernel.org/all/1642998653-21377-12-git-send-email-anshuman.khandual@arm.com/
- https://lore.kernel.org/all/1643348653-24367-1-git-send-email-anshuman.khandual@arm.com/
- https://lore.kernel.org/all/1645681014-3346-1-git-send-email-anshuman.khandual@arm.com/
This series applies on v5.17-rc7
perf API
The series being applied
- Clean : tools/perf/check-headers.sh
- Clean : diff -u tools/include/uapi/linux/perf_event.h include/uapi/linux/perf_event.h
Todo
- Update perf report tool to process PERF_BR_EXTEND_ABI (when available),
then fetch and report branch types from perf_branch_entry.new_type field.
References
- BRBE captured branch record information
https://developer.arm.com/documentation/ddi0601/2021-12/AArch64-Registers/BRBINF-n--EL1--Branch-Record-Buffer-Information-Register--n-?lang=en
- BRBE based perf branch stack implementation on arm64 platform
https://lore.kernel.org/all/1642998653-21377-1-git-send-email-anshuman.khandual@arm.com/
Cc: Peter Zijlstra <peterz at infradead.org>
Cc: Ingo Molnar <mingo at redhat.com>
Cc: Arnaldo Carvalho de Melo <acme at kernel.org>
Cc: Mark Rutland <mark.rutland at arm.com>
Cc: Alexander Shishkin <alexander.shishkin at linux.intel.com>
Cc: Jiri Olsa <jolsa at redhat.com>
Cc: Namhyung Kim <namhyung at kernel.org>
Cc: Thomas Gleixner <tglx at linutronix.de>
Cc: Will Deacon <will at kernel.org>
Cc: linux-arm-kernel at lists.infradead.org
Cc: linux-perf-users at vger.kernel.org
Cc: linux-kernel at vger.kernel.org
Anshuman Khandual (8):
perf: Add irq and exception return branch types
perf: Add system error and not in transaction branch types
perf: Extend branch type classification
perf: Capture branch privilege information
perf/tools: Add irq and exception return branch types
perf/tools: Add system error and not in transaction branch types
perf/tools: Extend branch type classification
perf/tools: Add branch privilege information request flag
arch/x86/events/intel/lbr.c | 6 ++---
include/uapi/linux/perf_event.h | 31 +++++++++++++++++++++++-
tools/include/uapi/linux/perf_event.h | 31 +++++++++++++++++++++++-
tools/perf/Documentation/perf-record.txt | 1 +
tools/perf/util/branch.c | 7 +++++-
tools/perf/util/parse-branch-options.c | 1 +
6 files changed, 71 insertions(+), 6 deletions(-)
--
2.25.1
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