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Derek Foreman 8e746e95c3 perf data: Allow filtering conversion by time range
This adds a feature to allow restricting the range of converted samples
with a range string like perf-script and perf-report --time.

Committer testing:

Put a probe on the ICMP receive path handling broadcast packets:

  # perf probe icmp_rcv:64
  Added new event:
    probe:icmp_rcv_L64   (on icmp_rcv:64)

  You can now use it in all perf tools, such as:

  	perf record -e probe:icmp_rcv_L64 -aR sleep 1

  # perf record -e probe:icmp_rcv_L64 ping -c 10 -b 127.255.255.255
  WARNING: pinging broadcast address
  PING 127.255.255.255 (127.255.255.255) 56(84) bytes of data.
  ^C
  --- 127.255.255.255 ping statistics ---
  10 packets transmitted, 0 received, 100% packet loss, time 9217ms

  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.034 MB perf.data (10 samples) ]

  # perf script
              ping   52785 [009]  5847.300394: probe:icmp_rcv_L64: (ffffffffaadb337e)
              ping   52785 [009]  5848.325018: probe:icmp_rcv_L64: (ffffffffaadb337e)
              ping   52785 [009]  5849.349007: probe:icmp_rcv_L64: (ffffffffaadb337e)
              ping   52785 [009]  5850.372979: probe:icmp_rcv_L64: (ffffffffaadb337e)
              ping   52785 [009]  5851.396988: probe:icmp_rcv_L64: (ffffffffaadb337e)
              ping   52785 [009]  5852.420954: probe:icmp_rcv_L64: (ffffffffaadb337e)
              ping   52785 [009]  5853.444934: probe:icmp_rcv_L64: (ffffffffaadb337e)
              ping   52785 [009]  5854.468926: probe:icmp_rcv_L64: (ffffffffaadb337e)
              ping   52785 [009]  5855.492914: probe:icmp_rcv_L64: (ffffffffaadb337e)
              ping   52785 [009]  5856.516883: probe:icmp_rcv_L64: (ffffffffaadb337e)
  #

Now get some slices using perf script:

  # perf script --time 40%
            ping   52785 [009]  5847.300394: probe:icmp_rcv_L64: (ffffffffaadb337e)
            ping   52785 [009]  5848.325018: probe:icmp_rcv_L64: (ffffffffaadb337e)
            ping   52785 [009]  5849.349007: probe:icmp_rcv_L64: (ffffffffaadb337e)
            ping   52785 [009]  5850.372979: probe:icmp_rcv_L64: (ffffffffaadb337e)
  # perf script --time 40%-60%
            ping   52785 [009]  5851.396988: probe:icmp_rcv_L64: (ffffffffaadb337e)
            ping   52785 [009]  5852.420954: probe:icmp_rcv_L64: (ffffffffaadb337e)
  #

And finally use this new feature:

  # perf data convert --to-json out.json --time 0%-10%
  [ perf data convert: Converted 'perf.data' into JSON data 'out.json' ]
  [ perf data convert: Converted and wrote 0.001 MB (1 samples) ]
  [ perf data convert: Skipped 9 samples ]
  # cat out.json
  {
  	"linux-perf-json-version": 1,
  	"headers": {
  		"header-version": 1,
  		"captured-on": "2026-01-06T22:26:40Z",
  		"data-offset": 520,
  		"data-size": 34648,
  		"feat-offset": 35168,
  		"hostname": "number",
  		"os-release": "6.17.12-300.fc43.x86_64",
  		"arch": "x86_64",
  		"cpu-desc": "AMD Ryzen 9 9950X3D 16-Core Processor",
  		"cpuid": "AuthenticAMD,26,68,0",
  		"nrcpus-online": 32,
  		"nrcpus-avail": 32,
  		"perf-version": "6.19.rc4.gf4c270685d3d",
  		"cmdline": [
  			"/home/acme/bin/perf"
  		]
  	},
  	"samples": [
  		{
  			"timestamp": 5847300394661,
  			"pid": 52785,
  			"tid": 52785,
  			"cpu": 9,
  			"comm": "ping",
  			"callchain": [
  				{
  					"ip": "0xffffffffaadb337f",
  					"symbol": "icmp_rcv",
  					"dso": "[kernel.kallsyms]"
  				}
  			],
  			"__probe_ip": "ffffffffaadb337e"
  		}
  	]
  }
  #

Signed-off-by: Derek Foreman <derek.foreman@collabora.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@linaro.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-01-06 19:20:02 -03:00
Documentation RISC-V updates for v6.19-rc3 2025-12-28 09:44:26 -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
arch Fix the AMD microcode Entrysign signature checking code to include more 2026-01-02 12:04:51 -08:00
block block-6.19-20260102 2026-01-02 12:15:59 -08:00
certs sign-file,extract-cert: use pkcs11 provider for OPENSSL MAJOR >= 3 2024-09-20 19:52:48 +03:00
crypto crypto: seqiv - Do not use req->iv after crypto_aead_encrypt 2025-12-19 14:47:06 +08:00
drivers Devicetree fixes for 6.19, part 2: 2026-01-04 16:57:47 -08:00
fs four smb3 server fixes 2026-01-02 09:24:43 -08:00
include - Make sure clang inlines trivial local_irq_* helpers 2026-01-04 07:21:18 -08:00
init Significant patch series in this pull request: 2025-12-06 14:01:20 -08:00
io_uring io_uring-6.19-20260102 2026-01-02 12:07:55 -08:00
ipc Significant patch series in this pull request: 2025-12-06 14:01:20 -08:00
kernel Power management fix for 6.19-rc4 2026-01-02 12:35:29 -08:00
lib idr: fix idr_alloc() returning an ID out of range 2025-12-23 11:23:11 -08:00
mm mm/ksm: fix pte_unmap_unlock of wrong address in break_ksm_pmd_entry 2025-12-23 11:23:17 -08:00
net Including fixes from Bluetooth and WiFi. Notably this includes the fix 2025-12-30 08:45:58 -08:00
rust 27 hotfixes. 12 are cc:stable, 18 are MM. 2025-12-29 11:40:38 -08:00
samples samples/ftrace: Adjust LoongArch register restore order in direct calls 2025-12-31 15:19:25 +08:00
scripts mcb: Add missing modpost build support 2025-12-27 20:48:01 +01:00
security kernel/kexec: change the prototype of kimage_map_segment() 2025-12-23 11:23:13 -08:00
sound ALSA: hda/realtek: fix PCI SSID for one of the HP 200 G2i laptop 2025-12-21 11:19:31 +01:00
tools perf data: Allow filtering conversion by time range 2026-01-06 19:20:02 -03:00
usr initramfs: add gen_init_cpio to hostprogs unconditionally 2025-11-26 21:55:40 +01:00
virt KVM fixes for 6.19-rc1 2025-12-18 18:38:45 +01:00
.clang-format s390/pci: Fix cyclic dead-lock in zpci_zdev_put() and zpci_scan_devices() 2025-12-14 11:03:58 +01:00
.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: remove trim_trailing_whitespace option 2024-06-13 16:47:52 +02:00
.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 Devicetree fixes for 6.19, part 2: 2026-01-04 16:57:47 -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 Including fixes from netfilter and CAN. 2025-12-19 07:55:35 +12:00
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 Devicetree fixes for 6.19, part 2: 2026-01-04 16:57:47 -08:00
Makefile Linux 6.19-rc4 2026-01-04 14:41:55 -08:00
README README: restructure with role-based documentation and guidelines 2025-11-29 08:40:33 -07:00

README

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


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



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