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Namhyung Kim 91a5bffa56 perf lock contention: Handle slab objects in -L/--lock-filter option
This is to filter lock contention from specific slab objects only.
Like in the lock symbol output, we can use '&' prefix to filter slab
object names.

  root@virtme-ng:/home/namhyung/project/linux# tools/perf/perf lock con -abl sleep 1
   contended   total wait     max wait     avg wait            address   symbol

           3     14.99 us     14.44 us      5.00 us   ffffffff851c0940   pack_mutex (mutex)
           2      2.75 us      2.56 us      1.38 us   ffff98d7031fb498   &task_struct (mutex)
           4      1.42 us       557 ns       355 ns   ffff98d706311400   &kmalloc-cg-512 (mutex)
           2       953 ns       714 ns       476 ns   ffffffff851c3620   delayed_uprobe_lock (mutex)
           1       929 ns       929 ns       929 ns   ffff98d7031fb538   &task_struct (mutex)
           3       561 ns       210 ns       187 ns   ffffffff84a8b3a0   text_mutex (mutex)
           1       479 ns       479 ns       479 ns   ffffffff851b4cf8   tracepoint_srcu_srcu_usage (mutex)
           2       320 ns       195 ns       160 ns   ffffffff851cf840   pcpu_alloc_mutex (mutex)
           1       212 ns       212 ns       212 ns   ffff98d7031784d8   &signal_cache (mutex)
           1       177 ns       177 ns       177 ns   ffffffff851b4c28   tracepoint_srcu_srcu_usage (mutex)

With the filter, it can show contentions from the task_struct only.

  root@virtme-ng:/home/namhyung/project/linux# tools/perf/perf lock con -abl -L '&task_struct' sleep 1
   contended   total wait     max wait     avg wait            address   symbol

           2      1.97 us      1.71 us       987 ns   ffff98d7032fd658   &task_struct (mutex)
           1      1.20 us      1.20 us      1.20 us   ffff98d7032fd6f8   &task_struct (mutex)

It can work with other aggregation mode:

  root@virtme-ng:/home/namhyung/project/linux# tools/perf/perf lock con -ab -L '&task_struct' sleep 1
   contended   total wait     max wait     avg wait         type   caller

           1     25.10 us     25.10 us     25.10 us        mutex   perf_event_exit_task+0x39
           1     21.60 us     21.60 us     21.60 us        mutex   futex_exit_release+0x21
           1      5.56 us      5.56 us      5.56 us        mutex   futex_exec_release+0x21

Committer testing:

  root@number:~# perf lock con -abl sleep 1
   contended   total wait     max wait     avg wait            address   symbol

           1     20.80 us     20.80 us     20.80 us   ffff9d417fbd65d0    (spinlock)
           8     12.85 us      2.41 us      1.61 us   ffff9d415eeb6a40   rq_lock (spinlock)
           1      2.55 us      2.55 us      2.55 us   ffff9d415f636a40   rq_lock (spinlock)
           7      1.92 us       840 ns       274 ns   ffff9d39c2cbc8c4    (spinlock)
           1      1.23 us      1.23 us      1.23 us   ffff9d415fb36a40   rq_lock (spinlock)
           2       928 ns       738 ns       464 ns   ffff9d39c1fa6660   &kmalloc-rnd-14-192 (rwlock)
           4       788 ns       252 ns       197 ns   ffffffffb8608a80   jiffies_lock (spinlock)
           1       304 ns       304 ns       304 ns   ffff9d39c2c979c4    (spinlock)
           1       216 ns       216 ns       216 ns   ffff9d3a0225c660   &kmalloc-rnd-14-192 (rwlock)
           1        89 ns        89 ns        89 ns   ffff9d3a0adbf3e0   &kmalloc-rnd-14-192 (rwlock)
           1        61 ns        61 ns        61 ns   ffff9d415f9b6a40   rq_lock (spinlock)
  root@number:~# uname -r
  6.13.0-rc2
  root@number:~#

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: Chun-Tse Shao <ctshao@google.com>
Cc: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Kees Cook <kees@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Song Liu <song@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Link: https://lore.kernel.org/r/20241220060009.507297-5-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2024-12-23 13:53:08 -03:00
arch OpenRISC fixes for 6.13-rc3 2024-12-12 13:20:53 -08:00
block blk-mq: move cpuhp callback registering out of q->sysfs_lock 2024-12-06 09:48:46 -07:00
certs sign-file,extract-cert: use pkcs11 provider for OPENSSL MAJOR >= 3 2024-09-20 19:52:48 +03:00
crypto module: Convert symbol namespace to string literal 2024-12-02 11:34:44 -08:00
Documentation Including fixes from bluetooth, netfilter and wireless. 2024-12-12 11:28:05 -08:00
drivers Including fixes from bluetooth, netfilter and wireless. 2024-12-12 11:28:05 -08:00
fs three kernel server fixes 2024-12-12 17:33:20 -08:00
include Including fixes from bluetooth, netfilter and wireless. 2024-12-12 11:28:05 -08:00
init - The series "resource: A couple of cleanups" from Andy Shevchenko 2024-11-25 16:09:48 -08:00
io_uring io_uring: Change res2 parameter type in io_uring_cmd_done 2024-12-03 06:33:13 -07:00
ipc - The series "resource: A couple of cleanups" from Andy Shevchenko 2024-11-25 16:09:48 -08:00
kernel Probes fixes for v6.13-rc1: 2024-12-10 18:15:25 -08:00
lib - Remove if_not_guard() as it is generating incorrect code 2024-12-09 10:34:41 -08:00
LICENSES LICENSES: add 0BSD license text 2024-09-01 20:43:24 -07:00
mm 24 hotfixes. 17 are cc:stable. 15 are MM and 9 are non-MM. 2024-12-08 11:26:13 -08:00
net Including fixes from bluetooth, netfilter and wireless. 2024-12-12 11:28:05 -08:00
rust block-6.13-20242901 2024-11-30 15:47:29 -08:00
samples BPF fixes: 2024-12-06 15:07:48 -08:00
scripts openrisc: place exception table at the head of vmlinux 2024-12-10 12:04:19 +00:00
security Including fixes from can and netfilter. 2024-12-05 10:25:06 -08:00
sound sound fixes for 6.13-rc2 2024-12-06 11:46:39 -08:00
tools perf lock contention: Handle slab objects in -L/--lock-filter option 2024-12-23 13:53:08 -03:00
usr initramfs: shorten cmd_initfs in usr/Makefile 2024-07-16 01:07:52 +09:00
virt VFIO updates for v6.13 2024-11-27 12:57:03 -08:00
.clang-format clang-format: Update with v6.11-rc1's for_each macro list 2024-08-02 13:20:31 +02:00
.clippy.toml rust: enable Clippy's check-private-items 2024-10-07 21:39:57 +02:00
.cocciconfig
.editorconfig .editorconfig: remove trim_trailing_whitespace option 2024-06-13 16:47:52 +02:00
.get_maintainer.ignore MAINTAINERS: Retire Ralf Baechle 2024-11-12 15:48:59 +01:00
.gitattributes .gitattributes: set diff driver for Rust source code files 2023-05-31 17:48:25 +02:00
.gitignore Kbuild updates for v6.13 2024-11-30 13:41:50 -08:00
.mailmap media updates for v6.13-rc1 2024-11-20 14:01:15 -08:00
.rustfmt.toml rust: add .rustfmt.toml 2022-09-28 09:02:20 +02:00
COPYING
CREDITS cgroup: Changes for v6.13 2024-11-20 09:54:49 -08:00
Kbuild Kbuild updates for v6.1 2022-10-10 12:00:45 -07:00
Kconfig
MAINTAINERS Including fixes from bluetooth, netfilter and wireless. 2024-12-12 11:28:05 -08:00
Makefile Linux 6.13-rc2 2024-12-08 14:03:39 -08:00
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.