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Linus Torvalds 891e8abed5 perf tools improvements and fixes for v6.12:
- Use BPF + BTF to collect and pretty print syscall and tracepoint arguments in
   'perf trace', done as an GSoC activity.
 
 - Data-type profiling improvements:
 
   - Cache debuginfo to speed up data type resolution.
 
   - Add the 'typecln' sort order, to show which cacheline in a target is hot or
     cold. The following shows members in the cfs_rq's first cache line:
 
       $ perf report -s type,typecln,typeoff -H
       ...
       -    2.67%        struct cfs_rq
          +    1.23%        struct cfs_rq: cache-line 2
          +    0.57%        struct cfs_rq: cache-line 4
          +    0.46%        struct cfs_rq: cache-line 6
          -    0.41%        struct cfs_rq: cache-line 0
                  0.39%        struct cfs_rq +0x14 (h_nr_running)
                  0.02%        struct cfs_rq +0x38 (tasks_timeline.rb_leftmost)
 
   - When a typedef resolves to a unnamed struct, use the typedef name.
 
   - When a struct has just one basic type field (int, etc), resolve the type
     sort order to the name of the struct, not the type of the field.
 
   - Support type folding/unfolding in the data-type annotation TUI.
 
   - Fix bitfields offsets and sizes.
 
   - Initial support for PowerPC, using libcapstone and the usual objdump
     disassembly parsing routines.
 
 - Add support for disassembling and addr2line using the LLVM libraries,
   speeding up those operations.
 
 - Support --addr2line option in 'perf script' as with other tools.
 
 - Intel branch counters (LBR event logging) support, only available in recent
   Intel processors, for instance, the new "brcntr" field can be asked from
   'perf script' to print the information collected from this feature:
 
   $ perf script -F +brstackinsn,+brcntr
 
   # Branch counter abbr list:
   # branch-instructions:ppp = A
   # branch-misses = B
   # '-' No event occurs
   # '+' Event occurrences may be lost due to branch counter saturated
       tchain_edit  332203 3366329.405674:  53030 branch-instructions:ppp:    401781 f3+0x2c (home/sdp/test/tchain_edit)
          f3+31:
       0000000000401774   insn: eb 04                  br_cntr: AA  # PRED 5 cycles [5]
       000000000040177a   insn: 81 7d fc 0f 27 00 00
       0000000000401781   insn: 7e e3                  br_cntr: A   # PRED 1 cycles [6] 2.00 IPC
       0000000000401766   insn: 8b 45 fc
       0000000000401769   insn: 83 e0 01
       000000000040176c   insn: 85 c0
       000000000040176e   insn: 74 06                  br_cntr: A   # PRED 1 cycles [7] 4.00 IPC
       0000000000401776   insn: 83 45 fc 01
       000000000040177a   insn: 81 7d fc 0f 27 00 00
       0000000000401781   insn: 7e e3                  br_cntr: A   # PRED 7 cycles [14] 0.43 IPC
 
 - Support Timed PEBS (Precise Event-Based Sampling), a recent hardware feature
   in Intel processors.
 
 - Add 'perf ftrace profile' subcommand, using ftrace's function-graph tracer so
   that users can see the total, average, max execution time as well as the
   number of invocations easily, for instance:
 
   $ sudo perf ftrace profile -G __x64_sys_perf_event_open -- \
     perf stat -e cycles -C1 true 2> /dev/null | head
   # Total (us)  Avg (us)  Max (us)  Count  Function
         65.611    65.611    65.611      1  __x64_sys_perf_event_open
         30.527    30.527    30.527      1  anon_inode_getfile
         30.260    30.260    30.260      1  __anon_inode_getfile
         29.700    29.700    29.700      1  alloc_file_pseudo
         17.578    17.578    17.578      1  d_alloc_pseudo
         17.382    17.382    17.382      1  __d_alloc
         16.738    16.738    16.738      1  kmem_cache_alloc_lru
         15.686    15.686    15.686      1  perf_event_alloc
         14.012     7.006    11.264      2  obj_cgroup_charge
   #
 
 - 'perf sched timehist' improvements, including the addition of priority
   showing/filtering command line options.
 
 - Varios improvements to the 'perf probe', including 'perf test' regression
   testings.
 
 - Introduce the 'perf check', initially to check if some feature is in place,
   using it in 'perf test'.
 
 - Various fixes for 32-bit systems.
 
 - Address more leak sanitizer failures.
 
 - Fix memory leaks (LBR, disasm lock ops, etc).
 
 - More reference counting fixes (branch_info, etc).
 
 - Constify 'struct perf_tool' parameters to improve code generation and reduce
   the chances of having its internals changed, which isn't expected.
 
 - More constifications in various other places.
 
 - Add more build tests, including for JEVENTS.
 
 - Add more 'perf test' entries ('perf record LBR', pipe/inject, --setup-filter,
   'perf ftrace', 'cgroup sampling', etc).
 
 - Inject build ids for all entries in a call chain in 'perf inject', not just
   for the main sample.
 
 - Improve the BPF based sample filter, allowing root to setup filters in bpffs
   that then can be used by non-root users.
 
 - Allow filtering by cgroups with the BPF based sample filter.
 
 - Allow a more compact way for 'perf mem report' using the -T/--type-profile and
   also provide a --sort option similar to the one in 'perf report', 'perf top',
   to setup the sort order manually.
 
 - Fix --group behavior in 'perf annotate' when leader has no samples, where it
   was not showing anything even when other events in the group had samples.
 
 - Fix spinlock and rwlock accounting in 'perf lock contention'
 
 - Fix libsubcmd fixdep Makefile dependencies.
 
 - Improve 'perf ftrace' error message when ftrace isn't available.
 
 - Update various Intel JSON vendor event files.
 
 - ARM64 CoreSight hardware tracing infrastructure improvements, mostly not
   visible to users.
 
 - Update power10 JSON events.
 
 Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Merge tag 'perf-tools-for-v6.12-1-2024-09-19' of git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools

Pull perf tools updates from Arnaldo Carvalho de Melo:

 - Use BPF + BTF to collect and pretty print syscall and tracepoint
   arguments in 'perf trace', done as an GSoC activity

 - Data-type profiling improvements:

     - Cache debuginfo to speed up data type resolution

     - Add the 'typecln' sort order, to show which cacheline in a target
       is hot or cold. The following shows members in the cfs_rq's first
       cache line:

         $ perf report -s type,typecln,typeoff -H
         ...
         -    2.67%        struct cfs_rq
            +    1.23%        struct cfs_rq: cache-line 2
            +    0.57%        struct cfs_rq: cache-line 4
            +    0.46%        struct cfs_rq: cache-line 6
            -    0.41%        struct cfs_rq: cache-line 0
                    0.39%        struct cfs_rq +0x14 (h_nr_running)
                    0.02%        struct cfs_rq +0x38 (tasks_timeline.rb_leftmost)

     - When a typedef resolves to a unnamed struct, use the typedef name

     - When a struct has just one basic type field (int, etc), resolve
       the type sort order to the name of the struct, not the type of
       the field

     - Support type folding/unfolding in the data-type annotation TUI

     - Fix bitfields offsets and sizes

     - Initial support for PowerPC, using libcapstone and the usual
       objdump disassembly parsing routines

 - Add support for disassembling and addr2line using the LLVM libraries,
   speeding up those operations

 - Support --addr2line option in 'perf script' as with other tools

 - Intel branch counters (LBR event logging) support, only available in
   recent Intel processors, for instance, the new "brcntr" field can be
   asked from 'perf script' to print the information collected from this
   feature:

     $ perf script -F +brstackinsn,+brcntr

     # Branch counter abbr list:
     # branch-instructions:ppp = A
     # branch-misses = B
     # '-' No event occurs
     # '+' Event occurrences may be lost due to branch counter saturated
         tchain_edit  332203 3366329.405674:  53030 branch-instructions:ppp:    401781 f3+0x2c (home/sdp/test/tchain_edit)
            f3+31:
         0000000000401774   insn: eb 04                  br_cntr: AA  # PRED 5 cycles [5]
         000000000040177a   insn: 81 7d fc 0f 27 00 00
         0000000000401781   insn: 7e e3                  br_cntr: A   # PRED 1 cycles [6] 2.00 IPC
         0000000000401766   insn: 8b 45 fc
         0000000000401769   insn: 83 e0 01
         000000000040176c   insn: 85 c0
         000000000040176e   insn: 74 06                  br_cntr: A   # PRED 1 cycles [7] 4.00 IPC
         0000000000401776   insn: 83 45 fc 01
         000000000040177a   insn: 81 7d fc 0f 27 00 00
         0000000000401781   insn: 7e e3                  br_cntr: A   # PRED 7 cycles [14] 0.43 IPC

 - Support Timed PEBS (Precise Event-Based Sampling), a recent hardware
   feature in Intel processors

 - Add 'perf ftrace profile' subcommand, using ftrace's function-graph
   tracer so that users can see the total, average, max execution time
   as well as the number of invocations easily, for instance:

     $ sudo perf ftrace profile -G __x64_sys_perf_event_open -- \
       perf stat -e cycles -C1 true 2> /dev/null | head
     # Total (us)  Avg (us)  Max (us)  Count  Function
           65.611    65.611    65.611      1  __x64_sys_perf_event_open
           30.527    30.527    30.527      1  anon_inode_getfile
           30.260    30.260    30.260      1  __anon_inode_getfile
           29.700    29.700    29.700      1  alloc_file_pseudo
           17.578    17.578    17.578      1  d_alloc_pseudo
           17.382    17.382    17.382      1  __d_alloc
           16.738    16.738    16.738      1  kmem_cache_alloc_lru
           15.686    15.686    15.686      1  perf_event_alloc
           14.012     7.006    11.264      2  obj_cgroup_charge

 - 'perf sched timehist' improvements, including the addition of
   priority showing/filtering command line options

 - Varios improvements to the 'perf probe', including 'perf test'
   regression testings

 - Introduce the 'perf check', initially to check if some feature is
   in place, using it in 'perf test'

 - Various fixes for 32-bit systems

 - Address more leak sanitizer failures

 - Fix memory leaks (LBR, disasm lock ops, etc)

 - More reference counting fixes (branch_info, etc)

 - Constify 'struct perf_tool' parameters to improve code generation
   and reduce the chances of having its internals changed, which isn't
   expected

 - More constifications in various other places

 - Add more build tests, including for JEVENTS

 - Add more 'perf test' entries ('perf record LBR', pipe/inject,
   --setup-filter, 'perf ftrace', 'cgroup sampling', etc)

 - Inject build ids for all entries in a call chain in 'perf inject',
   not just for the main sample

 - Improve the BPF based sample filter, allowing root to setup filters
   in bpffs that then can be used by non-root users

 - Allow filtering by cgroups with the BPF based sample filter

 - Allow a more compact way for 'perf mem report' using the
   -T/--type-profile and also provide a --sort option similar to the one
   in 'perf report', 'perf top', to setup the sort order manually

 - Fix --group behavior in 'perf annotate' when leader has no samples,
   where it was not showing anything even when other events in the group
   had samples

 - Fix spinlock and rwlock accounting in 'perf lock contention'

 - Fix libsubcmd fixdep Makefile dependencies

 - Improve 'perf ftrace' error message when ftrace isn't available

 - Update various Intel JSON vendor event files

 - ARM64 CoreSight hardware tracing infrastructure improvements, mostly
   not visible to users

 - Update power10 JSON events

* tag 'perf-tools-for-v6.12-1-2024-09-19' of git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools: (310 commits)
  perf trace: Mark the 'head' arg in the set_robust_list syscall as coming from user space
  perf trace: Mark the 'rseq' arg in the rseq syscall as coming from user space
  perf env: Find correct branch counter info on hybrid
  perf evlist: Print hint for group
  tools: Drop nonsensical -O6
  perf pmu: To info add event_type_desc
  perf evsel: Add accessor for tool_event
  perf pmus: Fake PMU clean up
  perf list: Avoid potential out of bounds memory read
  perf help: Fix a typo ("bellow")
  perf ftrace: Detect whether ftrace is enabled on system
  perf test shell probe_vfs_getname: Remove extraneous '=' from probe line number regex
  perf build: Require at least clang 16.0.6 to build BPF skeletons
  perf trace: If a syscall arg is marked as 'const', assume it is coming _from_ userspace
  perf parse-events: Remove duplicated include in parse-events.c
  perf callchain: Allow symbols to be optional when resolving a callchain
  perf inject: Lazy build-id mmap2 event insertion
  perf inject: Add new mmap2-buildid-all option
  perf inject: Fix build ID injection
  perf annotate-data: Add pr_debug_scope()
  ...
2024-09-22 09:11:14 -07:00
arch bpf-next-6.12 2024-09-21 09:27:50 -07:00
block vfs-6.12.blocksize 2024-09-20 17:53:17 -07:00
certs kbuild: use $(src) instead of $(srctree)/$(src) for source directory 2024-05-10 04:34:52 +09:00
crypto crypto: aegis128 - Fix indentation issue in crypto_aegis128_process_crypt() 2024-09-13 18:26:52 +08:00
Documentation sched_ext: Initial pull request for v6.12 2024-09-21 09:44:57 -07:00
drivers sched_ext: Initial pull request for v6.12 2024-09-21 09:44:57 -07:00
fs bpf-next-6.12 2024-09-21 09:27:50 -07:00
include sched_ext: Initial pull request for v6.12 2024-09-21 09:44:57 -07:00
init sched_ext: Initial pull request for v6.12 2024-09-21 09:44:57 -07:00
io_uring slab updates for 6.12 2024-09-18 08:53:53 +02:00
ipc ipc/shm, mm: drop do_vma_munmap() 2024-09-03 21:15:52 -07:00
kernel perf: Fix topology_sibling_cpumask check warning on ARM 2024-09-22 09:03:22 -07:00
lib sched_ext: Initial pull request for v6.12 2024-09-21 09:44:57 -07:00
LICENSES LICENSES: add 0BSD license text 2024-09-01 20:43:24 -07:00
mm Many singleton patches - please see the various changelogs for details. 2024-09-21 08:20:50 -07:00
net bpf-next-6.12 2024-09-21 09:27:50 -07:00
rust Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2024-09-05 20:37:20 -07:00
samples bpf-next-6.12 2024-09-21 09:27:50 -07:00
scripts bpf-next-6.12 2024-09-21 09:27:50 -07:00
security bpf-next-6.12 2024-09-21 09:27:50 -07:00
sound sound updates for 6.12-rc1 2024-09-17 17:03:43 +02:00
tools perf tools improvements and fixes for v6.12: 2024-09-22 09:11:14 -07:00
usr initramfs: shorten cmd_initfs in usr/Makefile 2024-07-16 01:07:52 +09:00
virt KVM: use follow_pfnmap API 2024-09-17 01:06:59 -07:00
.clang-format Docs: Move clang-format from process/ to dev-tools/ 2024-06-26 16:36:00 -06:00
.cocciconfig
.editorconfig .editorconfig: remove trim_trailing_whitespace option 2024-06-13 16:47:52 +02:00
.get_maintainer.ignore Add Jeff Kirsher to .get_maintainer.ignore 2024-03-08 11:36:54 +00:00
.gitattributes .gitattributes: set diff driver for Rust source code files 2023-05-31 17:48:25 +02:00
.gitignore .gitignore: add .gcda files 2024-08-09 13:18:46 +01:00
.mailmap drm next for 6.12-rc1 2024-09-19 10:18:15 +02:00
.rustfmt.toml rust: add .rustfmt.toml 2022-09-28 09:02:20 +02:00
COPYING
CREDITS MAINTAINERS: Mark powerpc spufs as orphaned 2024-08-19 21:27:56 +10:00
Kbuild Kbuild updates for v6.1 2022-10-10 12:00:45 -07:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS sched_ext: Initial pull request for v6.12 2024-09-21 09:44:57 -07:00
Makefile Linux 6.11 2024-09-15 16:57:56 +02:00
README README: Fix spelling 2024-03-18 03:36:32 -06:00

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

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.