perf lock contention: Account contending locks too

Currently it accounts the contention using delta between timestamps in
lock:contention_begin and lock:contention_end tracepoints. But it means
the lock should see the both events during the monitoring period.

Actually there are 4 cases that happen with the monitoring:

monitoring period
/ \
| |
1: B------+-----------------------+--------E
2: B----+-------------E |
3: | B-----------+----E
4: | B-------------E |
| |
t0 t1

where B and E mean contention BEGIN and END, respectively. So it only
accounts the case 4 for now. It seems there's no way to handle the case
1. The case 2 might be handled if it saved the timestamp (t0), but it
lacks the information from the B notably the flags which shows the lock
types. Also it could be a nested lock which it currently ignores. So
I think we should ignore the case 2.

However we can handle the case 3 if we save the timestamp (t1) at the
end of the period. And then it can iterate the map entries in the
userspace and update the lock stat accordinly.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Reviewed-by: Ian Rogers <irogers@google.com>
Reviwed-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Song Liu <song@kernel.org>
Cc: bpf@vger.kernel.org
Link: https://lore.kernel.org/r/20240228053335.312776-1-namhyung@kernel.org

perf lock contention: Add --lock-cgroup option

The --lock-cgroup option shows lock contention stats break down by
cgroups.

Add LOCK_AGGR_CGROUP mode and use it instead of use_cgroup field.

$ sudo ./perf lock con -ab --lock-cgroup sleep 1
contended total wait max wait avg wait cgroup

8 15.70 us 6.34 us 1.96 us /
2 1.48 us 747 ns 738 ns /user.slice/.../app.slice/app-gnome-google\x2dchrome-6442.scope
1 848 ns 848 ns 848 ns /user.slice/.../session.slice/org.gnome.Shell@x11.service
1 220 ns 220 ns 220 ns /user.slice/.../session.slice/pipewire-pulse.service

For now, the cgroup mode only works with BPF (-b).

Committer notes:

Remove -g as it is used in the other tools with a clear meaning of
collect/show callchains. As agreed with Namhyung off list.

Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Hao Luo <haoluo@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <song@kernel.org>
Cc: bpf@vger.kernel.org
Link: https://lore.kernel.org/r/20230906174903.346486-4-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf lock contention: Update default map size to 16384

The BPF hash map will align the map size to a power of 2. So 10k would
be 16k anyway. Let's have the actual size to avoid confusions.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Hao Luo <haoluo@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <song@kernel.org>
Cc: bpf@vger.kernel.org
Link: https://lore.kernel.org/r/20230406210611.1622492-2-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf lock contention: Show lock type with address

Show lock type names after the symbol of locks if any. This can be
useful especially when it doesn't show the lock symbols.

The indentation before the lock type parenthesis is to recognize lock
symbols more easily.

$ sudo ./perf lock con -abl -- sleep 1
contended total wait max wait avg wait address symbol

44 6.13 ms 284.49 us 139.28 us ffffffff92e06080 tasklist_lock (rwlock)
159 983.38 us 12.38 us 6.18 us ffff8cc717c90000 siglock (spinlock)
10 679.90 us 153.35 us 67.99 us ffff8cdc2872aaf8 mmap_lock (rwsem)
9 558.11 us 180.67 us 62.01 us ffff8cd647914038 mmap_lock (rwsem)
78 228.56 us 7.82 us 2.93 us ffff8cc700061c00 (spinlock)
5 41.60 us 16.93 us 8.32 us ffffd853acb41468 (spinlock)
10 37.24 us 5.87 us 3.72 us ffff8cd560b5c200 siglock (spinlock)
4 11.17 us 3.97 us 2.79 us ffff8d053ddf0c80 rq_lock (spinlock)
1 7.86 us 7.86 us 7.86 us ffff8cd64791404c (spinlock)
1 4.13 us 4.13 us 4.13 us ffff8d053d930c80 rq_lock (spinlock)
7 3.98 us 1.67 us 568 ns ffff8ccb92479440 (mutex)
2 2.62 us 2.33 us 1.31 us ffff8cc702e6ede0 (rwlock)

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Hao Luo <haoluo@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <song@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Waiman Long <longman@redhat.com>
Cc: Will Deacon <will@kernel.org>
Cc: bpf@vger.kernel.org
Link: https://lore.kernel.org/r/20230313204825.2665483-2-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf lock contention: Show per-cpu rq_lock with address

Using the BPF_PROG_RUN mechanism, we can run a raw_tp BPF program to
collect some semi-global locks like per-cpu locks. Let's add runqueue
locks using bpf_per_cpu_ptr() helper.

$ sudo ./perf lock con -abl -- sleep 1
contended total wait max wait avg wait address symbol

248 3.25 ms 32.23 us 13.10 us ffff8cc75cfd2940 siglock
60 217.91 us 9.69 us 3.63 us ffff8cc700061c00
8 70.23 us 13.86 us 8.78 us ffff8cc703629484
4 56.32 us 35.81 us 14.08 us ffff8cc78b66f778 mmap_lock
4 16.70 us 5.18 us 4.18 us ffff8cc7036a0684
3 4.99 us 2.65 us 1.66 us ffff8d053da30c80 rq_lock
2 3.44 us 2.28 us 1.72 us ffff8d053dcf0c80 rq_lock
9 2.51 us 371 ns 278 ns ffff8ccb92479440
2 2.11 us 1.24 us 1.06 us ffff8d053db30c80 rq_lock
2 2.06 us 1.69 us 1.03 us ffff8d053d970c80 rq_lock

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Hao Luo <haoluo@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <song@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Waiman Long <longman@redhat.com>
Cc: Will Deacon <will@kernel.org>
Cc: bpf@vger.kernel.org
Link: https://lore.kernel.org/r/20230313204825.2665483-2-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf lock contention: Track and show siglock with address

Likewise, we can display siglock by following the pointer like
current->sighand->siglock.

$ sudo ./perf lock con -abl -- sleep 1
contended total wait max wait avg wait address symbol

16 2.18 ms 305.35 us 136.34 us ffffffff92e06080 tasklist_lock
28 521.78 us 31.16 us 18.63 us ffff8cc703783ec4
7 119.03 us 23.55 us 17.00 us ffff8ccb92479440
15 88.29 us 10.06 us 5.89 us ffff8cd560b5f380 siglock
7 37.67 us 9.16 us 5.38 us ffff8d053daf0c80
5 8.81 us 4.92 us 1.76 us ffff8d053d6b0c80

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Hao Luo <haoluo@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <song@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Waiman Long <longman@redhat.com>
Cc: Will Deacon <will@kernel.org>
Cc: bpf@vger.kernel.org
Link: https://lore.kernel.org/r/20230313204825.2665483-2-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf lock contention: Track and show mmap_lock with address

Sometimes there are severe contentions on the mmap_lock and we want
see it in the -l/--lock-addr output. However it cannot symbolize
the mmap_lock because it's allocated dynamically without symbols.

Stephane and Hao gave me an idea separately to display mmap_lock by
following the current->mm pointer. I added a flag to mark mmap_lock
after comparing the lock address so that it can show them differently.
With this change it can show mmap_lock like below:

$ sudo ./perf lock con -abl -- sleep 10
contended total wait max wait avg wait address symbol
...
16344 312.30 ms 2.22 ms 19.11 us ffff8cc702595640
17686 310.08 ms 1.49 ms 17.53 us ffff8cc7025952c0
3 84.14 ms 45.79 ms 28.05 ms ffff8cc78114c478 mmap_lock
3557 76.80 ms 68.75 us 21.59 us ffff8cc77ca3af58
1 68.27 ms 68.27 ms 68.27 ms ffff8cda745dfd70
9 54.53 ms 7.96 ms 6.06 ms ffff8cc7642a48b8 mmap_lock
14629 44.01 ms 60.00 us 3.01 us ffff8cc7625f9ca0
3481 42.63 ms 140.71 us 12.24 us ffffffff937906ac vmap_area_lock
16194 38.73 ms 42.15 us 2.39 us ffff8cd397cbc560
11 38.44 ms 10.39 ms 3.49 ms ffff8ccd6d12fbb8 mmap_lock
1 5.43 ms 5.43 ms 5.43 ms ffff8cd70018f0d8
1674 5.38 ms 422.93 us 3.21 us ffffffff92e06080 tasklist_lock
581 4.51 ms 130.68 us 7.75 us ffff8cc9b1259058
5 3.52 ms 1.27 ms 703.23 us ffff8cc754510070
112 3.47 ms 56.47 us 31.02 us ffff8ccee38b3120
381 3.31 ms 73.44 us 8.69 us ffffffff93790690 purge_vmap_area_lock
255 3.19 ms 36.35 us 12.49 us ffff8d053ce30c80

Note that mmap_lock was renamed some time ago and it needs to support
old kernels with a different name 'mmap_sem'.

Suggested-by: Hao Luo <haoluo@google.com>
Suggested-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <song@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Waiman Long <longman@redhat.com>
Cc: Will Deacon <will@kernel.org>
Cc: bpf@vger.kernel.org
Link: https://lore.kernel.org/r/20230313204825.2665483-2-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf lock contention: Support filters for different aggregation

It'd be useful to filter other than the current aggregation mode. For
example, users may want to see callstacks for specific locks only. Or
they may want tasks from a certain callstack.

The tracepoints already collected the information but it needs to check
the condition again when processing the event. And it needs to change
BPF to allow the key combinations.

The lock contentions on 'rcu_state' spinlock can be monitored:

$ sudo perf lock con -abv -L rcu_state sleep 1
...
contended total wait max wait avg wait type caller

4 151.39 us 62.57 us 37.85 us spinlock rcu_core+0xcb
0xffffffff81fd1666 _raw_spin_lock_irqsave+0x46
0xffffffff8172d76b rcu_core+0xcb
0xffffffff822000eb __softirqentry_text_start+0xeb
0xffffffff816a0ba9 __irq_exit_rcu+0xc9
0xffffffff81fc0112 sysvec_apic_timer_interrupt+0xa2
0xffffffff82000e46 asm_sysvec_apic_timer_interrupt+0x16
0xffffffff81d49f78 cpuidle_enter_state+0xd8
0xffffffff81d4a259 cpuidle_enter+0x29
1 30.21 us 30.21 us 30.21 us spinlock rcu_core+0xcb
0xffffffff81fd1666 _raw_spin_lock_irqsave+0x46
0xffffffff8172d76b rcu_core+0xcb
0xffffffff822000eb __softirqentry_text_start+0xeb
0xffffffff816a0ba9 __irq_exit_rcu+0xc9
0xffffffff81fc00c4 sysvec_apic_timer_interrupt+0x54
0xffffffff82000e46 asm_sysvec_apic_timer_interrupt+0x16
1 28.84 us 28.84 us 28.84 us spinlock rcu_accelerate_cbs_unlocked+0x40
0xffffffff81fd1c60 _raw_spin_lock+0x30
0xffffffff81728cf0 rcu_accelerate_cbs_unlocked+0x40
0xffffffff8172da82 rcu_core+0x3e2
0xffffffff822000eb __softirqentry_text_start+0xeb
0xffffffff816a0ba9 __irq_exit_rcu+0xc9
0xffffffff81fc0112 sysvec_apic_timer_interrupt+0xa2
0xffffffff82000e46 asm_sysvec_apic_timer_interrupt+0x16
0xffffffff81d49f78 cpuidle_enter_state+0xd8
...

To see tasks calling 'rcu_core' function:

$ sudo perf lock con -abt -S rcu_core sleep 1
contended total wait max wait avg wait pid comm

19 23.46 us 2.21 us 1.23 us 0 swapper
2 18.37 us 17.01 us 9.19 us 2061859 ThreadPoolForeg
3 5.76 us 1.97 us 1.92 us 3909 pipewire-pulse
1 2.26 us 2.26 us 2.26 us 1809271 MediaSu~isor #2
1 1.97 us 1.97 us 1.97 us 1514882 Chrome_ChildIOT
1 987 ns 987 ns 987 ns 3740 pipewire-pulse

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Hao Luo <haoluo@google.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <song@kernel.org>
Cc: bpf@vger.kernel.org
Link: https://lore.kernel.org/r/20230203021324.143540-4-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf lock contention: Add -l/--lock-addr option

The -l/--lock-addr option is to implement per-lock-instance contention
stat using LOCK_AGGR_ADDR. It displays lock address and optionally
symbol name if exists.

$ sudo ./perf lock con -abl sleep 1
contended total wait max wait avg wait address symbol

1 36.28 us 36.28 us 36.28 us ffff92615d6448b8
9 10.91 us 1.84 us 1.21 us ffffffffbaed50c0 rcu_state
1 10.49 us 10.49 us 10.49 us ffff9262ac4f0c80
8 4.68 us 1.67 us 585 ns ffffffffbae07a40 jiffies_lock
3 3.03 us 1.45 us 1.01 us ffff9262277861e0
1 924 ns 924 ns 924 ns ffff926095ba9d20
1 436 ns 436 ns 436 ns ffff9260bfda4f60

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Blake Jones <blakejones@google.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <song@kernel.org>
Cc: bpf@vger.kernel.org
Link: https://lore.kernel.org/r/20221209190727.759804-4-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf lock contention: Add lock_data.h for common data

Accessing BPF maps should use the same data types. Add bpf_skel/lock_data.h
to define the common data structures. No functional changes.

Committer notes:

Fixed contention_key.stack_id missing rename to contention_key.stack_or_task_id.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Blake Jones <blakejones@google.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <song@kernel.org>
Cc: bpf@vger.kernel.org
Link: https://lore.kernel.org/r/20221209190727.759804-2-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>