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Jin Yao 6f7164fa23 perf report: Sort by sampled cycles percent per block for stdio
It would be useful to support sorting for all blocks by the sampled
cycles percent per block. This is useful to concentrate on the globally
hottest blocks.

This patch implements a new option "--total-cycles" which sorts all
blocks by 'Sampled Cycles%'. The 'Sampled Cycles%' is the percent:

 percent = block sampled cycles aggregation / total sampled cycles

Note that, this patch only supports "--stdio" mode.

For example,

  # perf record -b ./div
  # perf report --total-cycles --stdio
  # To display the perf.data header info, please use --header/--header-only options.
  #
  # Total Lost Samples: 0
  #
  # Samples: 2M of event 'cycles'
  # Event count (approx.): 2753248
  #
  # Sampled Cycles%  Sampled Cycles  Avg Cycles%  Avg Cycles                             [Program Block Range]      Shared Object
  # ...............  ..............  ...........  ..........  ................................................  .................
  #
             26.04%            2.8M        0.40%          18                            [div.c:42 -> div.c:39]                div
             15.17%            1.2M        0.16%           7                [random_r.c:357 -> random_r.c:380]       libc-2.27.so
              5.11%          402.0K        0.04%           2                            [div.c:27 -> div.c:28]                div
              4.87%          381.6K        0.04%           2                    [random.c:288 -> random.c:291]       libc-2.27.so
              4.53%          381.0K        0.04%           2                            [div.c:40 -> div.c:40]                div
              3.85%          300.9K        0.02%           1                            [div.c:22 -> div.c:25]                div
              3.08%          241.1K        0.02%           1                          [rand.c:26 -> rand.c:27]       libc-2.27.so
              3.06%          240.0K        0.02%           1                    [random.c:291 -> random.c:291]       libc-2.27.so
              2.78%          215.7K        0.02%           1                    [random.c:298 -> random.c:298]       libc-2.27.so
              2.52%          198.3K        0.02%           1                    [random.c:293 -> random.c:293]       libc-2.27.so
              2.36%          184.8K        0.02%           1                          [rand.c:28 -> rand.c:28]       libc-2.27.so
              2.33%          180.5K        0.02%           1                    [random.c:295 -> random.c:295]       libc-2.27.so
              2.28%          176.7K        0.02%           1                    [random.c:295 -> random.c:295]       libc-2.27.so
              2.20%          168.8K        0.02%           1                        [rand@plt+0 -> rand@plt+0]                div
              1.98%          158.2K        0.02%           1                [random_r.c:388 -> random_r.c:388]       libc-2.27.so
              1.57%          123.3K        0.02%           1                            [div.c:42 -> div.c:44]                div
              1.44%          116.0K        0.42%          19                [random_r.c:357 -> random_r.c:394]       libc-2.27.so
              0.25%          182.5K        0.02%           1                [random_r.c:388 -> random_r.c:391]       libc-2.27.so
              0.00%              48        1.07%          48        [x86_pmu_enable+284 -> x86_pmu_enable+298]  [kernel.kallsyms]
              0.00%              74        1.64%          74             [vm_mmap_pgoff+0 -> vm_mmap_pgoff+92]  [kernel.kallsyms]
              0.00%              73        1.62%          73                         [vm_mmap+0 -> vm_mmap+48]  [kernel.kallsyms]
              0.00%              63        0.69%          31                       [up_write+0 -> up_write+34]  [kernel.kallsyms]
              0.00%              13        0.29%          13      [setup_arg_pages+396 -> setup_arg_pages+413]  [kernel.kallsyms]
              0.00%               3        0.07%           3      [setup_arg_pages+418 -> setup_arg_pages+450]  [kernel.kallsyms]
              0.00%             616        6.84%         308   [security_mmap_file+0 -> security_mmap_file+72]  [kernel.kallsyms]
              0.00%              23        0.51%          23  [security_mmap_file+77 -> security_mmap_file+87]  [kernel.kallsyms]
              0.00%               4        0.02%           1                  [sched_clock+0 -> sched_clock+4]  [kernel.kallsyms]
              0.00%               4        0.02%           1                 [sched_clock+9 -> sched_clock+12]  [kernel.kallsyms]
              0.00%               1        0.02%           1                [rcu_nmi_exit+0 -> rcu_nmi_exit+9]  [kernel.kallsyms]

Committer testing:

This should provide material for hours of endless joy, both from looking
for suspicious things in the implementation of this patch, such as the
top one:

  # Sampled Cycles%  Sampled Cycles  Avg Cycles%  Avg Cycles                          [Program Block Range]     Shared Object
              2.17%            1.7M        0.08%         607   [compiler.h:199 -> common.c:221]              [kernel.vmlinux]

As well from things that look legit:

  # Sampled Cycles%  Sampled Cycles  Avg Cycles%  Avg Cycles                          [Program Block Range]     Shared Object
              0.16%          123.0K        0.60%        4.7K   [nospec-branch.h:265 -> nospec-branch.h:278]  [kernel.vmlinux]

:-)

Very short system wide taken branches session:

  # perf record -h -b

   Usage: perf record [<options>] [<command>]
      or: perf record [<options>] -- <command> [<options>]

      -b, --branch-any      sample any taken branches

  #
  # perf record -b
  ^C[ perf record: Woken up 595 times to write data ]
  [ perf record: Captured and wrote 156.672 MB perf.data (196873 samples) ]

  #
  # perf evlist -v
  cycles: size: 112, { sample_period, sample_freq }: 4000, sample_type: IP|TID|TIME|CPU|PERIOD|BRANCH_STACK, read_format: ID, disabled: 1, inherit: 1, mmap: 1, comm: 1, freq: 1, task: 1, precise_ip: 3, sample_id_all: 1, exclude_guest: 1, mmap2: 1, comm_exec: 1, ksymbol: 1, bpf_event: 1, branch_sample_type: ANY
  #
  # perf report --total-cycles --stdio
  # To display the perf.data header info, please use --header/--header-only options.
  #
  # Total Lost Samples: 0
  #
  # Samples: 6M of event 'cycles'
  # Event count (approx.): 6299936
  #
  # Sampled Cycles%  Sampled Cycles  Avg Cycles%  Avg Cycles                                                   [Program Block Range]         Shared Object
  # ...............  ..............  ...........  ..........  ......................................................................  ....................
  #
              2.17%            1.7M        0.08%         607                                        [compiler.h:199 -> common.c:221]      [kernel.vmlinux]
              1.75%            1.3M        8.34%       65.5K    [memset-vec-unaligned-erms.S:147 -> memset-vec-unaligned-erms.S:151]          libc-2.29.so
              0.72%          544.5K        0.03%         230                                      [entry_64.S:657 -> entry_64.S:662]      [kernel.vmlinux]
              0.56%          541.8K        0.09%         672                                        [compiler.h:199 -> common.c:300]      [kernel.vmlinux]
              0.39%          293.2K        0.01%         104                                    [list_debug.c:43 -> list_debug.c:61]      [kernel.vmlinux]
              0.36%          278.6K        0.03%         272                                    [entry_64.S:1289 -> entry_64.S:1308]      [kernel.vmlinux]
              0.30%          260.8K        0.07%         564                              [clear_page_64.S:47 -> clear_page_64.S:50]      [kernel.vmlinux]
              0.28%          215.3K        0.05%         369                                            [traps.c:623 -> traps.c:628]      [kernel.vmlinux]
              0.23%          178.1K        0.04%         278                                      [entry_64.S:271 -> entry_64.S:275]      [kernel.vmlinux]
              0.20%          152.6K        0.09%         706                                      [paravirt.c:177 -> paravirt.c:179]      [kernel.vmlinux]
              0.20%          155.8K        0.05%         373                                      [entry_64.S:153 -> entry_64.S:175]      [kernel.vmlinux]
              0.18%          136.6K        0.03%         222                                                [msr.h:105 -> msr.h:166]      [kernel.vmlinux]
              0.16%          123.0K        0.60%        4.7K                            [nospec-branch.h:265 -> nospec-branch.h:278]      [kernel.vmlinux]
              0.16%          118.3K        0.01%          44                                      [entry_64.S:632 -> entry_64.S:657]      [kernel.vmlinux]
              0.14%          104.5K        0.00%          28                                          [rwsem.c:1541 -> rwsem.c:1544]      [kernel.vmlinux]
              0.13%           99.2K        0.01%          53                                      [spinlock.c:150 -> spinlock.c:152]      [kernel.vmlinux]
              0.13%           95.5K        0.00%          35                                              [swap.c:456 -> swap.c:471]      [kernel.vmlinux]
              0.12%           96.2K        0.05%         407                              [copy_user_64.S:175 -> copy_user_64.S:209]      [kernel.vmlinux]
              0.11%           85.9K        0.00%          31                                        [swap.c:400 -> page-flags.h:188]      [kernel.vmlinux]
              0.10%           73.0K        0.01%          52                                          [paravirt.h:763 -> list.h:131]      [kernel.vmlinux]
              0.07%           56.2K        0.03%         214                                      [filemap.c:1524 -> filemap.c:1557]      [kernel.vmlinux]
              0.07%           54.2K        0.02%         145                                        [memory.c:1032 -> memory.c:1049]      [kernel.vmlinux]
              0.07%           50.3K        0.00%          39                                            [mmzone.c:49 -> mmzone.c:69]      [kernel.vmlinux]
              0.06%           48.3K        0.01%          40                                   [paravirt.h:768 -> page_alloc.c:3304]      [kernel.vmlinux]
              0.06%           46.7K        0.02%         155                                        [memory.c:1032 -> memory.c:1056]      [kernel.vmlinux]
              0.06%           46.9K        0.01%         103                                              [swap.c:867 -> swap.c:902]      [kernel.vmlinux]
              0.06%           47.8K        0.00%          34                                    [entry_64.S:1201 -> entry_64.S:1202]      [kernel.vmlinux]

 -----------------------------------------------------------

 v7:
 ---
 Use use_browser in report__browse_block_hists for supporting
 stdio and potential tui mode.

 v6:
 ---
 Create report__browse_block_hists in block-info.c (codes are
 moved from builtin-report.c). It's called from
 perf_evlist__tty_browse_hists.

 v5:
 ---
 1. Move all block functions to block-info.c

 2. Move the code of setting ms in block hist_entry to
    other patch.

 v4:
 ---
 1. Use new option '--total-cycles' to replace
    '-s total_cycles' in v3.

 2. Move block info collection out of block info
    printing.

 v3:
 ---
 1. Use common function block_info__process_sym to
    process the blocks per symbol.

 2. Remove the nasty hack for skipping calculation
    of column length

 3. Some minor cleanup

Signed-off-by: Jin Yao <yao.jin@linux.intel.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jin Yao <yao.jin@intel.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20191107074719.26139-6-yao.jin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-11-07 10:14:48 -03:00
arch perf/x86: Synchronize PMU task contexts on optimized context switches 2019-10-28 12:51:01 +01:00
block blk-rq-qos: fix first node deletion of rq_qos_del() 2019-10-15 10:13:13 -06:00
certs PKCS#7: Refactor verify_pkcs7_signature() 2019-08-05 18:40:18 -04:00
crypto Merge branch 'next-lockdown' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security 2019-09-28 08:14:15 -07:00
Documentation ARM: SoC fixes 2019-10-25 16:00:47 -04:00
drivers Merge branch 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-10-27 06:55:55 -04:00
fs Seven cifs/smb3 fixes, including three for stable 2019-10-27 06:41:52 -04:00
include perf/core, perf/x86: Introduce swap_task_ctx() method at 'struct pmu' 2019-10-28 12:50:59 +01:00
init Merge branch 'next-lockdown' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security 2019-09-28 08:14:15 -07:00
ipc ipc/sem.c: convert to use built-in RCU list checking 2019-09-25 17:51:41 -07:00
kernel perf/core: Optimize perf_init_event() for TYPE_SOFTWARE 2019-10-28 12:53:28 +01:00
lib lib/vdso: Make clock_getres() POSIX compliant again 2019-10-23 14:48:23 +02:00
LICENSES LICENSES: Rename other to deprecated 2019-05-03 06:34:32 -06:00
mm mm/thp: allow dropping THP from page cache 2019-10-19 06:32:33 -04:00
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2019-10-19 17:09:11 -04:00
samples Merge branch 'perf/urgent' into perf/core, to pick up fixes 2019-10-28 12:38:26 +01:00
scripts Modules fixes for v5.4-rc5 2019-10-25 16:11:55 -04:00
security perf_event: Add support for LSM and SELinux checks 2019-10-17 21:31:55 +02:00
sound ALSA: hda: Add Tigerlake/Jasperlake PCI ID 2019-10-23 06:28:50 +02:00
tools perf report: Sort by sampled cycles percent per block for stdio 2019-11-07 10:14:48 -03:00
usr kbuild: update compile-test header list for v5.4-rc2 2019-10-05 15:29:49 +09:00
virt KVM/arm fixes for 5.4, take #2 2019-10-22 13:31:29 +02:00
.clang-format clang-format: Update with the latest for_each macro list 2019-08-31 10:00:51 +02:00
.cocciconfig
.get_maintainer.ignore Opt out of scripts/get_maintainer.pl 2019-05-16 10:53:40 -07:00
.gitattributes .gitattributes: set git diff driver for C source code files 2016-10-07 18:46:30 -07:00
.gitignore Modules updates for v5.4 2019-09-22 10:34:46 -07:00
.mailmap A few MIPS fixes: 2019-10-26 19:43:12 -04:00
COPYING COPYING: use the new text with points to the license files 2018-03-23 12:41:45 -06:00
CREDITS MAINTAINERS: Remove Simon as Renesas SoC Co-Maintainer 2019-10-10 08:12:51 -07:00
Kbuild kbuild: do not descend to ./Kbuild when cleaning 2019-08-21 21:03:58 +09:00
Kconfig docs: kbuild: convert docs to ReST and rename to *.rst 2019-06-14 14:21:21 -06:00
MAINTAINERS Merge branch 'perf/urgent' into perf/core, to pick up fixes 2019-10-28 12:38:26 +01:00
Makefile Linux 5.4-rc5 2019-10-27 13:19:19 -04:00
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.