linux.git/tools/perf/Documentation, branch v6.9

perf: script: prefer capstone to XED

2024-02-21T02:07:34+00:00

Now perf can show assembly instructions with libcapstone for x86, and the
capstone is better in general.

Signed-off-by: Changbin Du 
Reviewed-by: Adrian Hunter 
Cc: changbin.du@gmail.com
Cc: Thomas Richter 
Cc: Andi Kleen 
Signed-off-by: Namhyung Kim 
Link: https://lore.kernel.org/r/20240217074046.4100789-6-changbin.du@huawei.com

perf: script: add raw|disasm arguments to --insn-trace option

2024-02-21T02:07:21+00:00

Now '--insn-trace' accept a argument to specify the output format:
  - raw: display raw instructions.
  - disasm: display mnemonic instructions (if capstone is installed).

$ sudo perf script --insn-trace=raw
              ls 1443864 [006] 2275506.209908875:      7f216b426100 _start+0x0 (/usr/lib/x86_64-linux-gnu/ld-2.31.so) insn: 48 89 e7
              ls 1443864 [006] 2275506.209908875:      7f216b426103 _start+0x3 (/usr/lib/x86_64-linux-gnu/ld-2.31.so) insn: e8 e8 0c 00 00
              ls 1443864 [006] 2275506.209908875:      7f216b426df0 _dl_start+0x0 (/usr/lib/x86_64-linux-gnu/ld-2.31.so) insn: f3 0f 1e fa

$ sudo perf script --insn-trace=disasm
              ls 1443864 [006] 2275506.209908875:      7f216b426100 _start+0x0 (/usr/lib/x86_64-linux-gnu/ld-2.31.so)		movq %rsp, %rdi
              ls 1443864 [006] 2275506.209908875:      7f216b426103 _start+0x3 (/usr/lib/x86_64-linux-gnu/ld-2.31.so)		callq _dl_start+0x0
              ls 1443864 [006] 2275506.209908875:      7f216b426df0 _dl_start+0x0 (/usr/lib/x86_64-linux-gnu/ld-2.31.so)	illegal instruction
              ls 1443864 [006] 2275506.209908875:      7f216b426df4 _dl_start+0x4 (/usr/lib/x86_64-linux-gnu/ld-2.31.so)	pushq %rbp
              ls 1443864 [006] 2275506.209908875:      7f216b426df5 _dl_start+0x5 (/usr/lib/x86_64-linux-gnu/ld-2.31.so)	movq %rsp, %rbp
              ls 1443864 [006] 2275506.209908875:      7f216b426df8 _dl_start+0x8 (/usr/lib/x86_64-linux-gnu/ld-2.31.so)	pushq %r15

Signed-off-by: Changbin Du 
Reviewed-by: Adrian Hunter 
Cc: changbin.du@gmail.com
Cc: Thomas Richter 
Cc: Andi Kleen 
Signed-off-by: Namhyung Kim 
Link: https://lore.kernel.org/r/20240217074046.4100789-5-changbin.du@huawei.com

perf: script: add field 'disasm' to display mnemonic instructions

2024-02-21T02:07:07+00:00

In addition to the 'insn' field, this adds a new field 'disasm' to
display mnemonic instructions instead of the raw code.

$ sudo perf script -F +disasm
       perf-exec 1443864 [006] 2275506.209848:          psb:  psb offs: 0                                      0 [unknown] ([unknown])
       perf-exec 1443864 [006] 2275506.209848:          cbr:  cbr: 41 freq: 4100 MHz (114%)                    0 [unknown] ([unknown])
              ls 1443864 [006] 2275506.209905:          1  branches:uH:      7f216b426100 _start+0x0 (/usr/lib/x86_64-linux-gnu/ld-2.31.so)	movq %rsp, %rdi
              ls 1443864 [006] 2275506.209908:          1  branches:uH:      7f216b426103 _start+0x3 (/usr/lib/x86_64-linux-gnu/ld-2.31.so)	callq _dl_start+0x0

Signed-off-by: Changbin Du 
Reviewed-by: Adrian Hunter 
Cc: changbin.du@gmail.com
Cc: Thomas Richter 
Cc: Andi Kleen 
Signed-off-by: Namhyung Kim 
Link: https://lore.kernel.org/r/20240217074046.4100789-4-changbin.du@huawei.com

Merge branch 'perf-tools' into perf-tools-next

2024-02-12T20:19:21+00:00

To get some fixes in the perf test and JSON metrics into the development
branch.

Signed-off-by: Namhyung Kim

perf stat: Support per-cluster aggregation

2024-02-09T22:59:53+00:00

Some platforms have 'cluster' topology and CPUs in the cluster will
share resources like L3 Cache Tag (for HiSilicon Kunpeng SoC) or L2
cache (for Intel Jacobsville). Currently parsing and building cluster
topology have been supported since [1].

perf stat has already supported aggregation for other topologies like
die or socket, etc. It'll be useful to aggregate per-cluster to find
problems like L3T bandwidth contention.

This patch add support for "--per-cluster" option for per-cluster
aggregation. Also update the docs and related test. The output will
be like:

[root@localhost tmp]# perf stat -a -e LLC-load --per-cluster -- sleep 5

 Performance counter stats for 'system wide':

S56-D0-CLS158    4      1,321,521,570      LLC-load
S56-D0-CLS594    4        794,211,453      LLC-load
S56-D0-CLS1030    4             41,623      LLC-load
S56-D0-CLS1466    4             41,646      LLC-load
S56-D0-CLS1902    4             16,863      LLC-load
S56-D0-CLS2338    4             15,721      LLC-load
S56-D0-CLS2774    4             22,671      LLC-load
[...]

On a legacy system without cluster or cluster support, the output will
be look like:
[root@localhost perf]# perf stat -a -e cycles --per-cluster -- sleep 1

 Performance counter stats for 'system wide':

S56-D0-CLS0   64         18,011,485      cycles
S7182-D0-CLS0   64         16,548,835      cycles

Note that this patch doesn't mix the cluster information in the outputs
of --per-core to avoid breaking any tools/scripts using it.

Note that perf recently supports "--per-cache" aggregation, but it's not
the same with the cluster although cluster CPUs may share some cache
resources. For example on my machine all clusters within a die share the
same L3 cache:
$ cat /sys/devices/system/cpu/cpu0/cache/index3/shared_cpu_list
0-31
$ cat /sys/devices/system/cpu/cpu0/topology/cluster_cpus_list
0-3

[1] commit c5e22feffdd7 ("topology: Represent clusters of CPUs within a die")

Tested-by: Jie Zhan 
Reviewed-by: Tim Chen 
Reviewed-by: Ian Rogers 
Signed-off-by: Yicong Yang 
Cc: james.clark@arm.com
Cc: 21cnbao@gmail.com
Cc: prime.zeng@hisilicon.com
Cc: Jonathan.Cameron@huawei.com
Cc: fanghao11@huawei.com
Cc: linuxarm@huawei.com
Cc: tim.c.chen@intel.com
Cc: linux-arm-kernel@lists.infradead.org
Signed-off-by: Namhyung Kim 
Link: https://lore.kernel.org/r/20240208024026.2691-1-yangyicong@huawei.com

perf tools: Make it possible to see perf's kernel and module memory mappings

2024-02-08T23:49:39+00:00

Dump kmaps if using 'perf --debug kmaps' or verbose > 2 (e.g. -vvv) for
tools 'perf script' and 'perf report' if there is no browser.

Example:

  $ perf --debug kmaps script 2>&1 >/dev/null | grep kvm.intel
  build id event received for /lib/modules/6.7.2-local/kernel/arch/x86/kvm/kvm-intel.ko: 0691d75e10e72ebbbd45a44c59f6d00a5604badf [20]
  Map: 0-3a3 4f5d8 [kvm_intel].modinfo
  Map: 0-5240 5f280 [kvm_intel]__versions
  Map: 0-30 64 [kvm_intel].note.Linux
  Map: 0-14 644c0 [kvm_intel].orc_header
  Map: 0-5297 43680 [kvm_intel].rodata
  Map: 0-5bee 3b837 [kvm_intel].text.unlikely
  Map: 0-7e0 41430 [kvm_intel].noinstr.text
  Map: 0-2080 713c0 [kvm_intel].bss
  Map: 0-26 705c8 [kvm_intel].data..read_mostly
  Map: 0-5888 6a4c0 [kvm_intel].data
  Map: 0-22 70220 [kvm_intel].data.once
  Map: 0-40 705f0 [kvm_intel].data..percpu
  Map: 0-1685 41d20 [kvm_intel].init.text
  Map: 0-4b8 6fd60 [kvm_intel].init.data
  Map: 0-380 70248 [kvm_intel]__dyndbg
  Map: 0-8 70218 [kvm_intel].exit.data
  Map: 0-438 4f980 [kvm_intel]__param
  Map: 0-5f5 4ca0f [kvm_intel].rodata.str1.1
  Map: 0-3657 493b8 [kvm_intel].rodata.str1.8
  Map: 0-e0 70640 [kvm_intel].data..ro_after_init
  Map: 0-500 70ec0 [kvm_intel].gnu.linkonce.this_module
  Map: ffffffffc13a7000-ffffffffc1421000 a0 /lib/modules/6.7.2-local/kernel/arch/x86/kvm/kvm-intel.ko

The example above shows how the module section mappings are all wrong
except for the main .text mapping at 0xffffffffc13a7000.

Signed-off-by: Adrian Hunter 
Acked-by: Namhyung Kim 
Cc: Like Xu 
Signed-off-by: Namhyung Kim 
Link: https://lore.kernel.org/r/20240208085326.13432-2-adrian.hunter@intel.com

tools: perf: Expose sample ID / stream ID to python scripts

2024-02-03T02:05:40+00:00

perf script exposes the evsel_name to python scripts as part of the data
passed to the sample or tracepoint handler function, and it passes the id and
stream_id to the throttled/unthrottled handler functions. This makes matching
throttle events and samples difficult.

To make this possible, this change exposes the sample id and stream_id values
to the script.

Signed-off-by: Ben Gainey 
Reviewed-by: Adrian Hunter 
Cc: will@kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Signed-off-by: Namhyung Kim 
Link: https://lore.kernel.org/r/20240123103137.1890779-2-ben.gainey@arm.com

perf Documentation: Add some more hints to tips.txt

2024-02-02T06:18:18+00:00

Add some (hopefully useful) hints to tips.txt
Also some minor corrections.

Would probably good to make it a reviewer rule that if generally useful
options are added the patch must add an example to tips.txt

Signed-off-by: Andi Kleen 
Signed-off-by: Namhyung Kim 
Link: https://lore.kernel.org/r/20240131021352.151440-1-ak@linux.intel.com

perf list: Add output file option

2024-01-26T13:51:49+00:00

Add an option to write the 'perf list' output to a specific file. This
can avoid issues with debug output being written into the output stream.

Signed-off-by: Ian Rogers 
Acked-by: Namhyung Kim 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Athira Rajeev 
Cc: Ingo Molnar 
Cc: Jiri Olsa 
Cc: Kajol Jain 
Cc: Kan Liang 
Cc: Mark Rutland 
Cc: Peter Zijlstra 
Cc: Ravi Bangoria 
Cc: Ross Zwisler 
Cc: Shirisha G 
Link: https://lore.kernel.org/r/20240124043015.1388867-3-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Add -H short option for --hierarchy

2024-01-25T23:24:04+00:00

I found the hierarchy mode useful, but it's easy to make a typo when
using it.  Let's add a short option for that.

Also update the documentation. :)

Acked-by: Arnaldo Carvalho de Melo 
Link: https://lore.kernel.org/r/20240125055124.1579617-1-namhyung@kernel.org
Signed-off-by: Namhyung Kim