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Mike Leach 35cd0098ee perf: tools: cs-etm: Enhance raw Coresight trace debug display
When compiling perf with CORESIGHT=1, an additional build option may
be used: CSTRACE_RAW=1, which will cause the CoreSight formatted trace
frames to be printed out during a perf --dump command. This is useful
when investigating issues with trace generation, decode or possible
data corruption.

e.g. for ETMv4 trace source into a formatted ETR sink a dump -

. ... CoreSight ETMV4I Trace data: size 0x28c150 bytes
Idx:0; ID:14;	I_ASYNC : Alignment Synchronisation.
Idx:12; ID:14;	I_TRACE_INFO : Trace Info.; INFO=0x0 { CC.0 };
                Decoder Sync point TINFO
Idx:17; ID:14;	I_ADDR_L_64IS0 : Address, Long, 64 bit, IS0.;
                Addr=0x0000000000000000;

becomes with CSTRACE_RAW=1:

. ... CoreSight ETMV4I Trace data: size 0x28c150 bytes
Frame Data; Index 0; ID_DATA[0x14]; 00 00 00 00 00 00 00 00
                                    00 00 00 80 01 01
Idx:0; ID:14;	I_ASYNC : Alignment Synchronisation.
Frame Data; Index 16; ID_DATA[0x14]; 00 9d 00 00 00 00 00 00
                                     00 00 04 85 57 08 f2
Idx:12; ID:14;	I_TRACE_INFO : Trace Info.; INFO=0x0 { CC.0 };
                Decoder Sync point TINFO
Idx:17; ID:14;	I_ADDR_L_64IS0 : Address, Long, 64 bit, IS0.;
                Addr=0x0000000000000000;

CSTRACE_RAW=1 has no effect on ETE + TRBE trace as there is no trace
formatting in the TRBE buffer.

This patch enhances the output so that for each packet the individual
bytes associated with the packet are printed.

Thus for ETMv4 this now becomes:

. ... CoreSight ETMV4I Trace data: size 0x28c150 bytes
Frame Data; Index 0; ID_DATA[0x14]; 00 00 00 00 00 00 00 00
                                    00 00 00 80 01 01
Idx:0; ID:14;[0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x80];
             I_ASYNC : Alignment Synchronisation.
Frame Data; Index 16; ID_DATA[0x14]; 00 9d 00 00 00 00 00 00
                                     00 00 04 85 57 08 f2
Idx:12; ID:14; [0x01 0x01 0x00 ]; I_TRACE_INFO : Trace Info.; INFO=0x0
                                  { CC.0 }; Decoder Sync point TINFO
Idx:17; ID:14; [0x9d 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 ];
               I_ADDR_L_64IS0 : Address, Long, 64 bit, IS0.;
	       Addr=0x0000000000000000;

ETE trace output changes from:

Idx:0; ID:14; I_ASYNC : Alignment Synchronisation.
Idx:12; ID:14; I_TRACE_INFO : Trace Info.; INFO=0x0 { CC.0, TSTATE.0 };
               Decoder Sync point TINFO
Idx:15; ID:14; I_ADDR_L_64IS0 : Address, Long, 64 bit, IS0.;
               Addr=0xFFFF80007CF7F56C;
becoming:

Idx:0; ID:14;[0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x80];
              I_ASYNC : Alignment Synchronisation.
Idx:12; ID:14; [0x01 0x01 0x00 ]; I_TRACE_INFO : Trace Info.; INFO=0x0
               { CC.0, TSTATE.0 }; Decoder Sync point TINFO
Idx:15; ID:14; [0x9d 0x5b 0x7a 0xf7 0x7c 0x00 0x80 0xff 0xff ];
               I_ADDR_L_64IS0 : Address, Long, 64 bit, IS0.;
	       Addr=0xFFFF80007CF7F56C;

Tested-by: Leo Yan <leo.yan@arm.com>
Signed-off-by: Mike Leach <mike.leach@arm.com>
Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2026-03-18 11:48:09 -07:00
arch Convert remaining multi-line kmalloc_obj/flex GFP_KERNEL uses 2026-02-22 08:26:33 -08:00
block Convert remaining multi-line kmalloc_obj/flex GFP_KERNEL uses 2026-02-22 08:26:33 -08:00
certs Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
crypto x509: select CONFIG_CRYPTO_LIB_SHA256 2026-02-22 12:09:23 -08:00
Documentation RTC for 7.0 2026-02-22 09:43:11 -08:00
drivers RTC for 7.0 2026-02-22 09:43:11 -08:00
fs fsverity fixes for v7.0-rc1 2026-02-22 13:12:04 -08:00
include fsverity fixes for v7.0-rc1 2026-02-22 13:12:04 -08:00
init Convert 'alloc_flex' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
io_uring Convert 'alloc_flex' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
ipc Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
kernel Convert remaining multi-line kmalloc_obj/flex GFP_KERNEL uses 2026-02-22 08:26:33 -08:00
lib Crypto library fix for v7.0-rc1 2026-02-22 13:09:33 -08:00
LICENSES LICENSES: Add modern form of the LGPL-2.1 tags to the usage guide section 2025-10-22 07:58:19 +02:00
mm Convert remaining multi-line kmalloc_obj/flex GFP_KERNEL uses 2026-02-22 08:26:33 -08:00
net Convert remaining multi-line kmalloc_obj/flex GFP_KERNEL uses 2026-02-22 08:26:33 -08:00
rust Rust fixes for v7.0-rc1 2026-02-22 08:43:31 -08:00
samples USB / Thunderbolt changes for 7.0-rc1 2026-02-17 09:36:43 -08:00
scripts Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
security Convert remaining multi-line kmalloc_obj/flex GFP_KERNEL uses 2026-02-22 08:26:33 -08:00
sound Convert remaining multi-line kmalloc_obj/flex GFP_KERNEL uses 2026-02-22 08:26:33 -08:00
tools perf: tools: cs-etm: Enhance raw Coresight trace debug display 2026-03-18 11:48:09 -07:00
usr kbuild: uapi: drop dependency on CC_CAN_LINK 2026-01-16 15:02:11 -07:00
virt Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
.clang-format Devicetree updates for v7.0: 2026-02-11 18:27:08 -08:00
.clippy.toml rust: clean Rust 1.88.0's warning about clippy::disallowed_macros configuration 2025-05-07 00:11:47 +02:00
.cocciconfig
.editorconfig editorconfig: add rst extension 2026-01-26 19:07:09 -08:00
.get_maintainer.ignore MAINTAINERS: remove Alyssa Rosenzweig 2025-09-18 21:17:31 +02:00
.gitattributes .gitattributes: set diff driver for Rust source code files 2023-05-31 17:48:25 +02:00
.gitignore rust: kbuild: add proc macro library support 2025-11-24 17:15:36 +01:00
.mailmap Landlock update for v7.0-rc1 2026-02-11 15:57:08 -08:00
.pylintrc docs: Move the python libraries to tools/lib/python 2025-11-18 09:22:40 -07:00
.rustfmt.toml rust: add .rustfmt.toml 2022-09-28 09:02:20 +02:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS CREDITS: Add -next to Stephen Rothwell's entry 2026-02-22 12:11:33 -08:00
Kbuild sched: Make migrate_{en,dis}able() inline 2025-09-25 09:57:16 +02:00
Kconfig io_uring: Rename KConfig to Kconfig 2025-02-19 14:53:27 -07:00
MAINTAINERS EFI fixes for v7.0 #1 2026-02-20 12:04:40 -08:00
Makefile Linux 7.0-rc1 2026-02-22 13:18:59 -08:00
README docs: add AI Coding Assistants documentation 2026-01-06 14:55:06 -07:00

Linux kernel
============

The Linux kernel is the core of any Linux operating system. It manages hardware,
system resources, and provides the fundamental services for all other software.

Quick Start
-----------

* Report a bug: See Documentation/admin-guide/reporting-issues.rst
* Get the latest kernel: https://kernel.org
* Build the kernel: See Documentation/admin-guide/quickly-build-trimmed-linux.rst
* Join the community: https://lore.kernel.org/

Essential Documentation
-----------------------

All users should be familiar with:

* Building requirements: Documentation/process/changes.rst
* Code of Conduct: Documentation/process/code-of-conduct.rst
* License: See COPYING

Documentation can be built with make htmldocs or viewed online at:
https://www.kernel.org/doc/html/latest/


Who Are You?
============

Find your role below:

* New Kernel Developer - Getting started with kernel development
* Academic Researcher - Studying kernel internals and architecture
* Security Expert - Hardening and vulnerability analysis
* Backport/Maintenance Engineer - Maintaining stable kernels
* System Administrator - Configuring and troubleshooting
* Maintainer - Leading subsystems and reviewing patches
* Hardware Vendor - Writing drivers for new hardware
* Distribution Maintainer - Packaging kernels for distros
* AI Coding Assistant - LLMs and AI-powered development tools


For Specific Users
==================

New Kernel Developer
--------------------

Welcome! Start your kernel development journey here:

* Getting Started: Documentation/process/development-process.rst
* Your First Patch: Documentation/process/submitting-patches.rst
* Coding Style: Documentation/process/coding-style.rst
* Build System: Documentation/kbuild/index.rst
* Development Tools: Documentation/dev-tools/index.rst
* Kernel Hacking Guide: Documentation/kernel-hacking/hacking.rst
* Core APIs: Documentation/core-api/index.rst

Academic Researcher
-------------------

Explore the kernel's architecture and internals:

* Researcher Guidelines: Documentation/process/researcher-guidelines.rst
* Memory Management: Documentation/mm/index.rst
* Scheduler: Documentation/scheduler/index.rst
* Networking Stack: Documentation/networking/index.rst
* Filesystems: Documentation/filesystems/index.rst
* RCU (Read-Copy Update): Documentation/RCU/index.rst
* Locking Primitives: Documentation/locking/index.rst
* Power Management: Documentation/power/index.rst

Security Expert
---------------

Security documentation and hardening guides:

* Security Documentation: Documentation/security/index.rst
* LSM Development: Documentation/security/lsm-development.rst
* Self Protection: Documentation/security/self-protection.rst
* Reporting Vulnerabilities: Documentation/process/security-bugs.rst
* CVE Procedures: Documentation/process/cve.rst
* Embargoed Hardware Issues: Documentation/process/embargoed-hardware-issues.rst
* Security Features: Documentation/userspace-api/seccomp_filter.rst

Backport/Maintenance Engineer
-----------------------------

Maintain and stabilize kernel versions:

* Stable Kernel Rules: Documentation/process/stable-kernel-rules.rst
* Backporting Guide: Documentation/process/backporting.rst
* Applying Patches: Documentation/process/applying-patches.rst
* Subsystem Profile: Documentation/maintainer/maintainer-entry-profile.rst
* Git for Maintainers: Documentation/maintainer/configure-git.rst

System Administrator
--------------------

Configure, tune, and troubleshoot Linux systems:

* Admin Guide: Documentation/admin-guide/index.rst
* Kernel Parameters: Documentation/admin-guide/kernel-parameters.rst
* Sysctl Tuning: Documentation/admin-guide/sysctl/index.rst
* Tracing/Debugging: Documentation/trace/index.rst
* Performance Security: Documentation/admin-guide/perf-security.rst
* Hardware Monitoring: Documentation/hwmon/index.rst

Maintainer
----------

Lead kernel subsystems and manage contributions:

* Maintainer Handbook: Documentation/maintainer/index.rst
* Pull Requests: Documentation/maintainer/pull-requests.rst
* Managing Patches: Documentation/maintainer/modifying-patches.rst
* Rebasing and Merging: Documentation/maintainer/rebasing-and-merging.rst
* Development Process: Documentation/process/maintainer-handbooks.rst
* Maintainer Entry Profile: Documentation/maintainer/maintainer-entry-profile.rst
* Git Configuration: Documentation/maintainer/configure-git.rst

Hardware Vendor
---------------

Write drivers and support new hardware:

* Driver API Guide: Documentation/driver-api/index.rst
* Driver Model: Documentation/driver-api/driver-model/driver.rst
* Device Drivers: Documentation/driver-api/infrastructure.rst
* Bus Types: Documentation/driver-api/driver-model/bus.rst
* Device Tree Bindings: Documentation/devicetree/bindings/
* Power Management: Documentation/driver-api/pm/index.rst
* DMA API: Documentation/core-api/dma-api.rst

Distribution Maintainer
-----------------------

Package and distribute the kernel:

* Stable Kernel Rules: Documentation/process/stable-kernel-rules.rst
* ABI Documentation: Documentation/ABI/README
* Kernel Configuration: Documentation/kbuild/kconfig.rst
* Module Signing: Documentation/admin-guide/module-signing.rst
* Kernel Parameters: Documentation/admin-guide/kernel-parameters.rst
* Tainted Kernels: Documentation/admin-guide/tainted-kernels.rst

AI Coding Assistant
-------------------

CRITICAL: If you are an LLM or AI-powered coding assistant, you MUST read and
follow the AI coding assistants documentation before contributing to the Linux
kernel:

* Documentation/process/coding-assistants.rst

This documentation contains essential requirements about licensing, attribution,
and the Developer Certificate of Origin that all AI tools must comply with.


Communication and Support
=========================

* Mailing Lists: https://lore.kernel.org/
* IRC: #kernelnewbies on irc.oftc.net
* Bugzilla: https://bugzilla.kernel.org/
* MAINTAINERS file: Lists subsystem maintainers and mailing lists
* Email Clients: Documentation/process/email-clients.rst