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Adrian Hunter 5ef506130c perf top: Add --branch-history option
Add --branch-history option, to act the same as that option does for
perf report.

Example:

  $ cat tcallf.c
  volatile a = 10000, b = 100000, c;

  __attribute__((noinline)) f2()
  {
          c = a / b;
  }

  __attribute__((noinline)) f1()
  {
          f2();
          f2();
  }
  main()
  {
          while (1)
                  f1();
  }
  $ gcc -w -g -o tcallf tcallf.c
  $ ./tcallf &
  [1] 29409
  $ perf top -e cycles:u  -t $(pidof tcallf) --stdio --no-children --branch-history
     PerfTop:    3819 irqs/sec  kernel: 0.0%  exact:  0.0% lost: 0/0 drop: 0/0 [4000Hz cycles:u],  (target_tid: 29409)
  --------------------------------------------------------------------------------------------------------------------

      49.01%  tcallf.c:5   [.] f2    tcallf
              |
              |--24.91%--f2 tcallf.c:4
              |          |
              |          |--17.14%--f1 tcallf.c:11 (cycles:1)
              |          |          f1 tcallf.c:11
              |          |          f2 tcallf.c:6 (cycles:3)
              |          |          f2 tcallf.c:4
              |          |          f1 tcallf.c:10 (cycles:2)
              |          |          f1 tcallf.c:9
              |          |          main tcallf.c:16 (cycles:1)
              |          |          main tcallf.c:16
              |          |          main tcallf.c:16 (cycles:1)
              |          |          main tcallf.c:16
              |          |          f1 tcallf.c:12 (cycles:1)
              |          |          f1 tcallf.c:12
              |          |          f2 tcallf.c:6 (cycles:3)
              |          |          f2 tcallf.c:4
              |          |          f1 tcallf.c:11 (cycles:1 iter:1 avg_cycles:12)
              |          |          f1 tcallf.c:11
              |          |          f2 tcallf.c:6 (cycles:3 iter:1 avg_cycles:12)
              |          |          f2 tcallf.c:4
              |          |          f1 tcallf.c:10 (cycles:2 iter:1 avg_cycles:12)
              |          |
              |           --7.78%--f1 tcallf.c:10 (cycles:2)
              |                     f1 tcallf.c:9
              |                     main tcallf.c:16 (cycles:1)
              |                     main tcallf.c:16
              |                     main tcallf.c:16 (cycles:1)
              |                     main tcallf.c:16
              |                     f1 tcallf.c:12 (cycles:1)
              |                     f1 tcallf.c:12
              |                     f2 tcallf.c:6 (cycles:3)
              |                     f2 tcallf.c:4
              |                     f1 tcallf.c:11 (cycles:1)
              |                     f1 tcallf.c:11
              |                     f2 tcallf.c:6 (cycles:3)
              |                     f2 tcallf.c:4
              |                     f1 tcallf.c:10 (cycles:2 iter:1 avg_cycles:12)
              |                     f1 tcallf.c:9
              |                     main tcallf.c:16 (cycles:1 iter:1 avg_cycles:12)
              |                     main tcallf.c:16
              |                     main tcallf.c:16 (cycles:1 iter:1 avg_cycles:12)
  ...

  $ pkill tcallf
  [1]+  Terminated              ./tcallf

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20230330131833.12864-2-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
History 2023-04-04 09:39:56 -03:00
arch RISC-V Fixes for 6.3-rc2 2023-03-10 09:19:30 -08:00
block block-6.3-2023-03-03 2023-03-03 10:21:39 -08:00
certs Kbuild updates for v6.3 2023-02-26 11:53:25 -08:00
crypto Networking changes for 6.3. 2023-02-21 18:24:12 -08:00
Documentation Networking fixes for 6.3-rc2, including fixes from netfilter, bpf 2023-03-09 10:56:58 -08:00
drivers drm fixes for 6.3-rc2 2023-03-10 08:57:46 -08:00
fs Changes since last update: 2023-03-10 08:51:57 -08:00
include for-6.3-rc1-tag 2023-03-10 08:39:13 -08:00
init Kbuild updates for v6.3 2023-02-26 11:53:25 -08:00
io_uring io_uring: silence variable ‘prev’ set but not used warning 2023-03-09 10:10:58 -07:00
ipc Merge branch 'work.namespace' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2023-02-24 19:20:07 -08:00
kernel Networking fixes for 6.3-rc2, including fixes from netfilter, bpf 2023-03-09 10:56:58 -08:00
lib cpumask: re-introduce constant-sized cpumask optimizations 2023-03-05 14:30:34 -08:00
LICENSES LICENSES: Add the copyleft-next-0.3.1 license 2022-11-08 15:44:01 +01:00
mm mm: avoid gcc complaint about pointer casting 2023-03-04 14:03:27 -08:00
net nfsd-6.3 fixes: 2023-03-10 08:45:30 -08:00
rust Rust fixes for 6.3-rc1 2023-03-03 14:51:15 -08:00
samples LoongArch changes for v6.3 2023-03-01 09:27:00 -08:00
scripts Remove Intel compiler support 2023-03-05 10:49:37 -08:00
security capability: just use a 'u64' instead of a 'u32[2]' array 2023-03-01 10:01:22 -08:00
sound sound fixes for 6.3-rc1 2023-03-04 10:53:59 -08:00
tools perf top: Add --branch-history option 2023-04-04 09:39:56 -03:00
usr usr/gen_init_cpio.c: remove unnecessary -1 values from int file 2022-10-03 14:21:44 -07:00
virt KVM/riscv changes for 6.3 2023-02-15 12:33:28 -05:00
.clang-format cpumask: re-introduce constant-sized cpumask optimizations 2023-03-05 14:30:34 -08:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore get_maintainer: add Alan to .get_maintainer.ignore 2022-08-20 15:17:44 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for *.dtso files 2023-02-26 15:28:23 +09:00
.gitignore .gitignore: ignore *.cover and *.mbx 2023-02-05 18:51:22 +09:00
.mailmap drm fixes for 6.3-rc2 2023-03-10 08:57:46 -08:00
.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 There is no particular theme here - mainly quick hits all over the tree. 2023-02-23 17:55:40 -08:00
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 perf tools fixes for v6.3: 2023-03-10 08:18:46 -08:00
Makefile Linux 6.3-rc1 2023-03-05 14:52:03 -08:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -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 Restructured Text 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.