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134 Commits
| Author | SHA1 | Message | Date | |
|---|---|---|---|---|
Feng Yang
|
2b5b834cc3 |
perf kwork: Remove unreachable judgments
When s2[i] = '\0', if s1[i] != '\0', it will be judged by ret, and if s1[i] = '\0', it will be judegd by !s1[i]. So in reality, s2 [i] will never make a judgment Signed-off-by: Feng Yang <yangfeng@kylinos.cn> Reviewed-by: Ian Rogers <irogers@google.com> Link: https://lore.kernel.org/r/20250314031013.94480-1-yangfeng59949@163.com Signed-off-by: Namhyung Kim <namhyung@kernel.org> |
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Namhyung Kim
|
e1cde2d5e9 |
perf ftrace: Use atomic inc to update histogram in BPF
It should use an atomic instruction to update even if the histogram is keyed by delta as it's also used for stats. Cc: Gabriele Monaco <gmonaco@redhat.com> Link: https://lore.kernel.org/r/20250227191223.1288473-3-namhyung@kernel.org Signed-off-by: Namhyung Kim <namhyung@kernel.org> |
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Namhyung Kim
|
79056b3fe8 |
perf ftrace: Remove an unnecessary condition check in BPF
The bucket_num is set based on the {max,min}_latency already in
cmd_ftrace(), so no need to check it again in BPF. Also I found
that it didn't pass the max_latency to BPF. :)
No functional changes intended.
Cc: Gabriele Monaco <gmonaco@redhat.com>
Link: https://lore.kernel.org/r/20250227191223.1288473-2-namhyung@kernel.org
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
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Namhyung Kim
|
9c33441418 |
perf ftrace: Fix latency stats with BPF
When BPF collects the stats for the latency in usec, it first divides
the time by 1000. But that means it would have 0 if the delta is small
and won't update the total time properly.
Let's keep the stats in nsec always and adjust to usec before printing.
Before:
$ sudo ./perf ftrace latency -ab -T mutex_lock --hide-empty -- sleep 0.1
# DURATION | COUNT | GRAPH |
0 - 1 us | 765 | ############################################# |
1 - 2 us | 10 | |
2 - 4 us | 2 | |
4 - 8 us | 5 | |
# statistics (in usec)
total time: 0 <<<--- (here)
avg time: 0
max time: 6
min time: 0
count: 782
After:
$ sudo ./perf ftrace latency -ab -T mutex_lock --hide-empty -- sleep 0.1
# DURATION | COUNT | GRAPH |
0 - 1 us | 880 | ############################################ |
1 - 2 us | 13 | |
2 - 4 us | 8 | |
4 - 8 us | 3 | |
# statistics (in usec)
total time: 268 <<<--- (here)
avg time: 0
max time: 6
min time: 0
count: 904
Tested-by: Athira Rajeev <atrajeev@linux.ibm.com>
Cc: Gabriele Monaco <gmonaco@redhat.com>
Link: https://lore.kernel.org/r/20250227191223.1288473-1-namhyung@kernel.org
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
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Chun-Tse Shao
|
425bc88352 |
perf lock: Retrieve owner callstack in bpf program
This implements per-callstack aggregation of lock owners in addition to per-thread. The owner callstack is captured using `bpf_get_task_stack()` at `contention_begin()` and it also adds a custom stackid function for the owner stacks to be compared easily. The owner info is kept in a hash map using lock addr as a key to handle multiple waiters for the same lock. At `contention_end()`, it updates the owner lock stat based on the info that was saved at `contention_begin()`. If there are more waiters, it'd update the owner pid to itself as `contention_end()` means it gets the lock now. But it also needs to check the return value of the lock function in case task was killed by a signal or something. Signed-off-by: Chun-Tse Shao <ctshao@google.com> Tested-by: Athira Rajeev <atrajeev@linux.ibm.com> Link: https://lore.kernel.org/r/20250227003359.732948-3-ctshao@google.com Signed-off-by: Namhyung Kim <namhyung@kernel.org> |
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Chun-Tse Shao
|
17ae7f9049 |
perf lock: Add bpf maps for owner stack tracing
Add a struct and few bpf maps in order to tracing owner stack. `struct owner_tracing_data`: Contains owner's pid, stack id, timestamp for when the owner acquires lock, and the count of lock waiters. `stack_buf`: Percpu buffer for retrieving owner stacktrace. `owner_stacks`: For tracing owner stacktrace to customized owner stack id. `owner_data`: For tracing lock_address to `struct owner_tracing_data` in bpf program. `owner_stat`: For reporting owner stacktrace in usermode. Signed-off-by: Chun-Tse Shao <ctshao@google.com> Tested-by: Athira Rajeev <atrajeev@linux.ibm.com> Link: https://lore.kernel.org/r/20250227003359.732948-2-ctshao@google.com Signed-off-by: Namhyung Kim <namhyung@kernel.org> |
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Gabriele Monaco
|
4a75e8c3b2 |
perf ftrace latency: variable histogram buckets
The max-latency value can make the histogram smaller, but not larger, we have a maximum of 22 buckets and specifying a max-latency that would require more buckets has no effect. Dynamically allocate the buckets and compute the bucket number from the max latency as (max-min) / range + 2 If the maximum is not specified, we still set the bucket number to 22 and compute the maximum accordingly. Fail if the maximum is smaller than min+range, this way we make sure we always have 3 buckets: those below min, those above max and one in the middle. Since max-latency is not available in log2 mode, always use 22 buckets. Signed-off-by: Gabriele Monaco <gmonaco@redhat.com> Link: https://lore.kernel.org/r/20250207080446.77630-1-gmonaco@redhat.com Signed-off-by: Namhyung Kim <namhyung@kernel.org> |
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Howard Chu
|
013eb043f3 |
perf trace: Fix BPF loading failure (-E2BIG)
As reported by Namhyung Kim and acknowledged by Qiao Zhao (link:
https://lore.kernel.org/linux-perf-users/20241206001436.1947528-1-namhyung@kernel.org/),
on certain machines, perf trace failed to load the BPF program into the
kernel. The verifier runs perf trace's BPF program for up to 1 million
instructions, returning an E2BIG error, whereas the perf trace BPF
program should be much less complex than that. This patch aims to fix
the issue described above.
The E2BIG problem from clang-15 to clang-16 is cause by this line:
} else if (size < 0 && size >= -6) { /* buffer */
Specifically this check: size < 0. seems like clang generates a cool
optimization to this sign check that breaks things.
Making 'size' s64, and use
} else if ((int)size < 0 && size >= -6) { /* buffer */
Solves the problem. This is some Hogwarts magic.
And the unbounded access of clang-12 and clang-14 (clang-13 works this
time) is fixed by making variable 'aug_size' s64.
As for this:
-if (aug_size > TRACE_AUG_MAX_BUF)
- aug_size = TRACE_AUG_MAX_BUF;
+aug_size = args->args[index] > TRACE_AUG_MAX_BUF ? TRACE_AUG_MAX_BUF : args->args[index];
This makes the BPF skel generated by clang-18 work. Yes, new clangs
introduce problems too.
Sorry, I only know that it works, but I don't know how it works. I'm not
an expert in the BPF verifier. I really hope this is not a kernel
version issue, as that would make the test case (kernel_nr) *
(clang_nr), a true horror story. I will test it on more kernel versions
in the future.
Fixes:
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Namhyung Kim
|
86a12b92a9 |
perf ftrace: Display latency statistics at the end
Sometimes users also want to see average latency as well as histogram.
Display latency statistics like avg, max, min at the end.
$ sudo ./perf ftrace latency -ab -T synchronize_rcu -- ...
# DURATION | COUNT | GRAPH |
0 - 1 us | 0 | |
1 - 2 us | 0 | |
2 - 4 us | 0 | |
4 - 8 us | 0 | |
8 - 16 us | 0 | |
16 - 32 us | 0 | |
32 - 64 us | 0 | |
64 - 128 us | 0 | |
128 - 256 us | 0 | |
256 - 512 us | 0 | |
512 - 1024 us | 0 | |
1 - 2 ms | 0 | |
2 - 4 ms | 0 | |
4 - 8 ms | 0 | |
8 - 16 ms | 1 | ##### |
16 - 32 ms | 7 | ######################################## |
32 - 64 ms | 0 | |
64 - 128 ms | 0 | |
128 - 256 ms | 0 | |
256 - 512 ms | 0 | |
512 - 1024 ms | 0 | |
1 - ... s | 0 | |
# statistics (in usec)
total time: 171832
avg time: 21479
max time: 30906
min time: 15869
count: 8
Committer testing:
root@number:~# perf ftrace latency -nab --bucket-range 100 --max-latency 512 -T switch_mm_irqs_off sleep 1
# DURATION | COUNT | GRAPH |
0 - 100 ns | 314 | ## |
100 - 200 ns | 1843 | ############# |
200 - 300 ns | 1390 | ########## |
300 - 400 ns | 844 | ###### |
400 - 500 ns | 480 | ### |
500 - 512 ns | 315 | ## |
512 - ... ns | 16 | |
# statistics (in nsec)
total time: 2448936
avg time: 387
max time: 3285
min time: 82
count: 6328
root@number:~#
Reviewed-by: James Clark <james.clark@linaro.org>
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: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250107224352.1128669-1-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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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>
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Namhyung Kim
|
0c631ef07c |
perf lock contention: Resolve slab object name using BPF
The bpf_get_kmem_cache() kfunc can return an address of the slab cache
(kmem_cache). As it has the name of the slab cache from the iterator,
we can use it to symbolize some dynamic kernel locks in a slab.
Before:
root@virtme-ng:/home/namhyung/project/linux# tools/perf/perf lock con -abl sleep 1
contended total wait max wait avg wait address symbol
2 3.34 us 2.87 us 1.67 us ffff9d7800ad9600 (mutex)
2 2.16 us 1.93 us 1.08 us ffff9d7804b992d8 (mutex)
4 1.37 us 517 ns 343 ns ffff9d78036e6e00 (mutex)
1 1.27 us 1.27 us 1.27 us ffff9d7804b99378 (mutex)
2 845 ns 599 ns 422 ns ffffffff9e1c3620 delayed_uprobe_lock (mutex)
1 845 ns 845 ns 845 ns ffffffff9da0b280 jiffies_lock (spinlock)
2 377 ns 259 ns 188 ns ffffffff9e1cf840 pcpu_alloc_mutex (mutex)
1 305 ns 305 ns 305 ns ffffffff9e1b4cf8 tracepoint_srcu_srcu_usage (mutex)
1 295 ns 295 ns 295 ns ffffffff9e1c0940 pack_mutex (mutex)
1 232 ns 232 ns 232 ns ffff9d7804b7d8d8 (mutex)
1 180 ns 180 ns 180 ns ffffffff9e1b4c28 tracepoint_srcu_srcu_usage (mutex)
1 165 ns 165 ns 165 ns ffffffff9da8b3a0 text_mutex (mutex)
After:
root@virtme-ng:/home/namhyung/project/linux# tools/perf/perf lock con -abl sleep 1
contended total wait max wait avg wait address symbol
2 1.95 us 1.77 us 975 ns ffff9d5e852d3498 &task_struct (mutex)
1 1.18 us 1.18 us 1.18 us ffff9d5e852d3538 &task_struct (mutex)
4 1.12 us 354 ns 279 ns ffff9d5e841ca800 &kmalloc-cg-512 (mutex)
2 859 ns 617 ns 429 ns ffffffffa41c3620 delayed_uprobe_lock (mutex)
3 691 ns 388 ns 230 ns ffffffffa41c0940 pack_mutex (mutex)
3 421 ns 164 ns 140 ns ffffffffa3a8b3a0 text_mutex (mutex)
1 409 ns 409 ns 409 ns ffffffffa41b4cf8 tracepoint_srcu_srcu_usage (mutex)
2 362 ns 239 ns 181 ns ffffffffa41cf840 pcpu_alloc_mutex (mutex)
1 220 ns 220 ns 220 ns ffff9d5e82b534d8 &signal_cache (mutex)
1 215 ns 215 ns 215 ns ffffffffa41b4c28 tracepoint_srcu_srcu_usage (mutex)
Note that the name starts with '&' sign for slab objects to inform they
are dynamic locks. It won't give the accurate lock or type names but
it's still useful. We may add type info to the slab cache later to get
the exact name of the lock in the type later.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Ian Rogers <irogers@google.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.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/20241220060009.507297-4-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Namhyung Kim
|
e2c4dc54cd |
perf lock contention: Run BPF slab cache iterator
Recently the kernel got the kmem_cache iterator to traverse metadata of slab objects. This can be used to symbolize dynamic locks in a slab. The new slab_caches hash map will have the pointer of the kmem_cache as a key and save the name and a id. The id will be saved in the flags part of the lock. Signed-off-by: Namhyung Kim <namhyung@kernel.org> Acked-by: Ian Rogers <irogers@google.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexei Starovoitov <alexei.starovoitov@gmail.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/20241220060009.507297-3-namhyung@kernel.org [ Added change from Namhyung addressing review from Alexei: ] Link: https://lore.kernel.org/r/Z2dVdH3o5iF-KrWj@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> |
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Namhyung Kim
|
d8cc6da406 |
perf lock contention: Add and use LCB_F_TYPE_MASK
This is a preparation for the later change. It'll use more bits in the flags so let's rename the type part and use the mask to extract the type. Signed-off-by: Namhyung Kim <namhyung@kernel.org> Acked-by: Ian Rogers <irogers@google.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.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/20241220060009.507297-2-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> |
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Namhyung Kim
|
a5bbe6dd69 |
perf ftrace latency: Fix compiler error for clang 12
I noticed this error on CentOS 8.
CLANG /build/util/bpf_skel/.tmp/func_latency.bpf.o
Error at line 119: Unsupport signed division for DAG: 0x55829ee68a10: i64 = sdiv 0x55829ee68bb0, 0x55829ee69090, util/bpf_skel/func_latency.bpf.c:119:17 @[ util/bpf_skel/func_latency.bpf.c:84:5 ]Please convert to unsigned div/mod.
fatal error: error in backend: Cannot select: 0x55829ee68a10: i64 = sdiv 0x55829ee68bb0, 0x55829ee69090, util/bpf_skel/func_latency.bpf.c:119:17 @[ util/bpf_skel/func_latency.bpf.c:84:5 ]
0x55829ee68bb0: i64,ch = CopyFromReg 0x55829edc9a78, Register:i64 %5, util/bpf_skel/func_latency.bpf.c:119:17 @[ util/bpf_skel/func_latency.bpf.c:84:5 ]
0x55829ee68e20: i64 = Register %5
0x55829ee69090: i64,ch = load<(volatile dereferenceable load 4 from @bucket_range, !tbaa !160), zext from i32> 0x55829edc9a78, 0x55829ee68fc0, undef:i64, util/bpf_skel/func_latency.bpf.c:119:19 @[ util/bpf_skel/func_latency.bpf.c:84:5 ]
0x55829ee68fc0: i64 = BPFISD::Wrapper TargetGlobalAddress:i64<i32* @bucket_range> 0, util/bpf_skel/func_latency.bpf.c:119:19 @[ util/bpf_skel/func_latency.bpf.c:84:5 ]
0x55829ee68808: i64 = TargetGlobalAddress<i32* @bucket_range> 0, util/bpf_skel/func_latency.bpf.c:119:19 @[ util/bpf_skel/func_latency.bpf.c:84:5 ]
0x55829ee68530: i64 = undef
In function: func_end
PLEASE submit a bug report to https://bugs.llvm.org/ and include the crash backtrace, preprocessed source, and associated run script.
It complains about sdiv which is (s64)delta / (u32)bucket_range.
Let's cast the delta to u64 for division.
Committer testing:
Tested on:
$ head -2 /etc/os-release
NAME="Fedora Linux"
VERSION="40 (Toolbx Container Image)"
$ clang --version |& head -1
clang version 18.1.8 (Fedora 18.1.8-1.fc40)
$
root@number:~# perf ftrace latency --use-nsec --bucket-range=200 --min-latency 250 --max-latency=5000 -T switch_mm_irqs_off -a sleep 10
# DURATION | COUNT | GRAPH |
0 - 250 ns | 28 | ##### |
250 - 450 ns | 12 | ## |
450 - 650 ns | 10 | # |
650 - 850 ns | 9 | # |
850 - 1050 ns | 20 | ### |
1.05 - 1.25 us | 14 | ## |
1.25 - 1.45 us | 16 | ### |
1.45 - 1.65 us | 8 | # |
1.65 - 1.85 us | 11 | ## |
1.85 - 2.05 us | 7 | # |
2.05 - 2.25 us | 11 | ## |
2.25 - 2.45 us | 10 | # |
2.45 - 2.65 us | 7 | # |
2.65 - 2.85 us | 8 | # |
2.85 - 3.05 us | 7 | # |
3.05 - 3.25 us | 7 | # |
3.25 - 3.45 us | 10 | # |
3.45 - 3.65 us | 5 | |
3.65 - 3.85 us | 9 | # |
3.85 - 4.05 us | 2 | |
4.05 - 4.25 us | 6 | # |
4.25 - ... us | 23 | #### |
root@number:~#
Fixes:
|
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|
Gabriele Monaco
|
690a052a6d |
perf ftrace latency: Add --max-latency option
This patch adds a max-latency option as discussed, in case the number of
buckets is more than 22, we don't observe the setting (for now, let's
say).
By default or if 0 is passed, the value is automatically determined
based on the number of buckets, range and minimum, so that we fill all
available buffers (equivalent to the behaviour before this patch).
We now get something like this:
# perf ftrace latency --bucket-range=20 \
--min-latency 10 \
--max-latency=100 \
-T switch_mm_irqs_off -a sleep 2
# DURATION | COUNT | GRAPH |
0 - 10 us | 1731 | ################ |
10 - 30 us | 1 | |
30 - 50 us | 0 | |
50 - 70 us | 0 | |
70 - 90 us | 0 | |
90 - 100 us | 0 | |
100 - ... us | 0 | |
Note the maximum is observed also if it doesn't cover completely a full
range (the second to last range is 10us long to let the last start at
100 sharp), this looks to me more sensible and eases the computations,
since we don't need to account for the range while filling the buckets.
Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Clark Williams <williams@redhat.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20241112181214.1171244-5-acme@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
|
||
Arnaldo Carvalho de Melo
|
08b875b6bf |
perf ftrace latency: Introduce --min-latency to narrow down into a latency range
Things below and over will be in the first and last, outlier, buckets.
Without it:
# perf ftrace latency --use-nsec --use-bpf \
--bucket-range=200 \
-T switch_mm_irqs_off -a sleep 2
# DURATION | COUNT | GRAPH |
0 - 200 ns | 0 | |
200 - 400 ns | 44 | |
400 - 600 ns | 291 | # |
600 - 800 ns | 506 | ## |
800 - 1000 ns | 148 | |
1.00 - 1.20 us | 581 | ## |
1.20 - 1.40 us | 2199 | ########## |
1.40 - 1.60 us | 1048 | #### |
1.60 - 1.80 us | 1448 | ###### |
1.80 - 2.00 us | 1091 | ##### |
2.00 - 2.20 us | 517 | ## |
2.20 - 2.40 us | 318 | # |
2.40 - 2.60 us | 370 | # |
2.60 - 2.80 us | 271 | # |
2.80 - 3.00 us | 150 | |
3.00 - 3.20 us | 85 | |
3.20 - 3.40 us | 48 | |
3.40 - 3.60 us | 40 | |
3.60 - 3.80 us | 22 | |
3.80 - 4.00 us | 13 | |
4.00 - 4.20 us | 14 | |
4.20 - ... us | 626 | ## |
#
# perf ftrace latency --use-nsec --use-bpf \
--bucket-range=20 --min-latency=1200 \
-T switch_mm_irqs_off -a sleep 2
# DURATION | COUNT | GRAPH |
0 - 1200 ns | 1243 | ##### |
1.20 - 1.22 us | 141 | |
1.22 - 1.24 us | 202 | |
1.24 - 1.26 us | 209 | |
1.26 - 1.28 us | 219 | |
1.28 - 1.30 us | 208 | |
1.30 - 1.32 us | 245 | # |
1.32 - 1.34 us | 246 | # |
1.34 - 1.36 us | 224 | # |
1.36 - 1.38 us | 219 | |
1.38 - 1.40 us | 206 | |
1.40 - 1.42 us | 190 | |
1.42 - 1.44 us | 190 | |
1.44 - 1.46 us | 146 | |
1.46 - 1.48 us | 140 | |
1.48 - 1.50 us | 125 | |
1.50 - 1.52 us | 115 | |
1.52 - 1.54 us | 102 | |
1.54 - 1.56 us | 87 | |
1.56 - 1.58 us | 90 | |
1.58 - 1.60 us | 85 | |
1.60 - ... us | 5487 | ######################## |
#
Now we want focus on the latencies starting at 1.2us, with a finer
grained range of 20ns:
This is all on a live system, so statistically interesting, but not
narrowing down on the same numbers, so a 'perf ftrace latency record'
seems interesting to then use all on the same snapshot of latencies.
A --max-latency counterpart should come next, at first limiting the
max-latency to 20 * bucket-size, as we have a fixed buckets array with
20 + 2 entries (+ for the outliers) and thus would need to make it
larger for higher latencies.
We also may need a way to ask for not considering the out of range
values (first and last buckets) when drawing the buckets bars.
Co-developed-by: Gabriele Monaco <gmonaco@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Clark Williams <williams@redhat.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20241112181214.1171244-4-acme@kernel.org
Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
|
||
|
Arnaldo Carvalho de Melo
|
e8536dd47a |
perf ftrace latency: Introduce --bucket-range to ask for linear bucketing
In addition to showing it exponentially, using log2() to figure out the
histogram index, allow for showing it linearly:
The preexisting more, the default:
# perf ftrace latency --use-nsec --use-bpf \
-T switch_mm_irqs_off -a sleep 2
# DURATION | COUNT | GRAPH |
0 - 1 ns | 0 | |
1 - 2 ns | 0 | |
2 - 4 ns | 0 | |
4 - 8 ns | 0 | |
8 - 16 ns | 0 | |
16 - 32 ns | 0 | |
32 - 64 ns | 0 | |
64 - 128 ns | 238 | # |
128 - 256 ns | 1704 | ########## |
256 - 512 ns | 672 | ### |
512 - 1024 ns | 4458 | ########################## |
1 - 2 us | 677 | #### |
2 - 4 us | 5 | |
4 - 8 us | 0 | |
8 - 16 us | 0 | |
16 - 32 us | 0 | |
32 - 64 us | 0 | |
64 - 128 us | 0 | |
128 - 256 us | 0 | |
256 - 512 us | 0 | |
512 - 1024 us | 0 | |
1 - ... ms | 0 | |
#
The new histogram mode:
# perf ftrace latency --bucket-range=150 --use-nsec --use-bpf \
-T switch_mm_irqs_off -a sleep 2
# DURATION | COUNT | GRAPH |
0 - 1 ns | 0 | |
1 - 151 ns | 265 | # |
151 - 301 ns | 1797 | ########### |
301 - 451 ns | 258 | # |
451 - 601 ns | 289 | # |
601 - 751 ns | 2049 | ############# |
751 - 901 ns | 967 | ###### |
901 - 1051 ns | 513 | ### |
1.05 - 1.20 us | 114 | |
1.20 - 1.35 us | 559 | ### |
1.35 - 1.50 us | 189 | # |
1.50 - 1.65 us | 137 | |
1.65 - 1.80 us | 32 | |
1.80 - 1.95 us | 2 | |
1.95 - 2.10 us | 0 | |
2.10 - 2.25 us | 1 | |
2.25 - 2.40 us | 1 | |
2.40 - 2.55 us | 0 | |
2.55 - 2.70 us | 0 | |
2.70 - 2.85 us | 0 | |
2.85 - 3.00 us | 1 | |
3.00 - ... us | 4 | |
#
Co-developed-by: Gabriele Monaco <gmonaco@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Clark Williams <williams@redhat.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20241112181214.1171244-3-acme@kernel.org
Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
|
||
Kyle Meyer
|
9a1e106550 |
perf: Increase MAX_NR_CPUS to 4096
Systems have surpassed 2048 CPUs. Increase MAX_NR_CPUS to 4096. Bitmaps declared with MAX_NR_CPUS bits will increase from 256B to 512B, cpus_runtime will increase from 81960B to 163880B, and max_entries will increase from 8192B to 16384B. Reviewed-by: Ian Rogers <irogers@google.com> Reviewed-by: Leo Yan <leo.yan@arm.com> Signed-off-by: Kyle Meyer <kyle.meyer@hpe.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Ben Gainey <ben.gainey@arm.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Clark <james.clark@linaro.org> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: https://lore.kernel.org/r/20241206044035.1062032-2-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> |
||
|
Namhyung Kim
|
aa5c90601b |
Merge 'origin/master' into perf-tools-next
To get the fixes in the perf-tools branch. Resolved a conflict due to RISC-V's syscall table change. Signed-off-by: Namhyung Kim <namhyung@kernel.org> |
||
Tengda Wu
|
07dc3a6de3 |
perf stat: Support inherit events during fork() for bperf
bperf has a nice ability to share PMUs, but it still does not support
inherit events during fork(), resulting in some deviations in its stat
results compared with perf.
perf stat result:
$ ./perf stat -e cycles,instructions -- ./perf test -w sqrtloop
Performance counter stats for './perf test -w sqrtloop':
2,316,038,116 cycles
2,859,350,725 instructions
1.009603637 seconds time elapsed
1.004196000 seconds user
0.003950000 seconds sys
bperf stat result:
$ ./perf stat --bpf-counters -e cycles,instructions -- \
./perf test -w sqrtloop
Performance counter stats for './perf test -w sqrtloop':
18,762,093 cycles
23,487,766 instructions
1.008913769 seconds time elapsed
1.003248000 seconds user
0.004069000 seconds sys
In order to support event inheritance, two new bpf programs are added
to monitor the fork and exit of tasks respectively. When a task is
created, add it to the filter map to enable counting, and reuse the
`accum_key` of its parent task to count together with the parent task.
When a task exits, remove it from the filter map to disable counting.
After support:
$ ./perf stat --bpf-counters -e cycles,instructions -- \
./perf test -w sqrtloop
Performance counter stats for './perf test -w sqrtloop':
2,316,252,189 cycles
2,859,946,547 instructions
1.009422314 seconds time elapsed
1.003597000 seconds user
0.004270000 seconds sys
Signed-off-by: Tengda Wu <wutengda@huaweicloud.com>
Cc: song@kernel.org
Cc: bpf@vger.kernel.org
Link: https://lore.kernel.org/r/20241021110201.325617-2-wutengda@huaweicloud.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
|
||
|
Howard Chu
|
395d38419f |
perf trace augmented_raw_syscalls: Add more checks to pass the verifier
Add some more checks to pass the verifier in more kernels. Signed-off-by: Howard Chu <howardchu95@gmail.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alan Maguire <alan.maguire@oracle.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: https://lore.kernel.org/r/20241011021403.4089793-3-howardchu95@gmail.com [ Reduced the patch removing things that can be done later ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> |
||
|
Arnaldo Carvalho de Melo
|
ecabac70ff |
perf trace augmented_raw_syscalls: Add extra array index bounds checking to satisfy some BPF verifiers
In a RHEL8 kernel (4.18.0-513.11.1.el8_9.x86_64), that, as enterprise
kernels go, have backports from modern kernels, the verifier complains
about lack of bounds check for the index into the array of syscall
arguments, on a BPF bytecode generated by clang 17, with:
; } else if (size < 0 && size >= -6) { /* buffer */
116: (b7) r1 = -6
117: (2d) if r1 > r6 goto pc-30
R0=map_value(id=0,off=0,ks=4,vs=24688,imm=0) R1_w=inv-6 R2=map_value(id=0,off=16,ks=4,vs=8272,imm=0) R3=inv(id=0) R5=inv40 R6=inv(id=0,umin_value=18446744073709551610,var_off=(0xffffffff00000000; 0xffffffff)) R7=map_value(id=0,off=56,ks=4,vs=8272,imm=0) R8=invP6 R9=map_value(id=0,off=20,ks=4,vs=24,imm=0) R10=fp0 fp-8=mmmmmmmm fp-16=map_value fp-24=map_value fp-32=inv40 fp-40=ctx fp-48=map_value fp-56=inv1 fp-64=map_value fp-72=map_value fp-80=map_value
; index = -(size + 1);
118: (a7) r6 ^= -1
119: (67) r6 <<= 32
120: (77) r6 >>= 32
; aug_size = args->args[index];
121: (67) r6 <<= 3
122: (79) r1 = *(u64 *)(r10 -24)
123: (0f) r1 += r6
last_idx 123 first_idx 116
regs=40 stack=0 before 122: (79) r1 = *(u64 *)(r10 -24)
regs=40 stack=0 before 121: (67) r6 <<= 3
regs=40 stack=0 before 120: (77) r6 >>= 32
regs=40 stack=0 before 119: (67) r6 <<= 32
regs=40 stack=0 before 118: (a7) r6 ^= -1
regs=40 stack=0 before 117: (2d) if r1 > r6 goto pc-30
regs=42 stack=0 before 116: (b7) r1 = -6
R0_w=map_value(id=0,off=0,ks=4,vs=24688,imm=0) R1_w=inv1 R2_w=map_value(id=0,off=16,ks=4,vs=8272,imm=0) R3_w=inv(id=0) R5_w=inv40 R6_rw=invP(id=0,smin_value=-2147483648,smax_value=0) R7_w=map_value(id=0,off=56,ks=4,vs=8272,imm=0) R8_w=invP6 R9_w=map_value(id=0,off=20,ks=4,vs=24,imm=0) R10=fp0 fp-8=mmmmmmmm fp-16_w=map_value fp-24_r=map_value fp-32_w=inv40 fp-40=ctx fp-48=map_value fp-56_w=inv1 fp-64_w=map_value fp-72=map_value fp-80=map_value
parent didn't have regs=40 stack=0 marks
last_idx 110 first_idx 98
regs=40 stack=0 before 110: (6d) if r1 s> r6 goto pc+5
regs=42 stack=0 before 109: (b7) r1 = 1
regs=40 stack=0 before 108: (65) if r6 s> 0x1000 goto pc+7
regs=40 stack=0 before 98: (55) if r6 != 0x1 goto pc+9
R0_w=map_value(id=0,off=0,ks=4,vs=24688,imm=0) R1_w=invP12 R2_w=map_value(id=0,off=16,ks=4,vs=8272,imm=0) R3_rw=inv(id=0) R5_w=inv24 R6_rw=invP(id=0,smin_value=-2147483648,smax_value=2147483647) R7_w=map_value(id=0,off=40,ks=4,vs=8272,imm=0) R8_rw=invP4 R9_w=map_value(id=0,off=12,ks=4,vs=24,imm=0) R10=fp0 fp-8=mmmmmmmm fp-16_rw=map_value fp-24_r=map_value fp-32_rw=invP24 fp-40_r=ctx fp-48_r=map_value fp-56_w=invP1 fp-64_rw=map_value fp-72_r=map_value fp-80_r=map_value
parent already had regs=40 stack=0 marks
124: (79) r6 = *(u64 *)(r1 +16)
R0=map_value(id=0,off=0,ks=4,vs=24688,imm=0) R1_w=map_value(id=0,off=0,ks=4,vs=8272,umax_value=34359738360,var_off=(0x0; 0x7fffffff8),s32_max_value=2147483640,u32_max_value=-8) R2=map_value(id=0,off=16,ks=4,vs=8272,imm=0) R3=inv(id=0) R5=inv40 R6_w=invP(id=0,umax_value=34359738360,var_off=(0x0; 0x7fffffff8),s32_max_value=2147483640,u32_max_value=-8) R7=map_value(id=0,off=56,ks=4,vs=8272,imm=0) R8=invP6 R9=map_value(id=0,off=20,ks=4,vs=24,imm=0) R10=fp0 fp-8=mmmmmmmm fp-16=map_value fp-24=map_value fp-32=inv40 fp-40=ctx fp-48=map_value fp-56=inv1 fp-64=map_value fp-72=map_value fp-80=map_value
R1 unbounded memory access, make sure to bounds check any such access
processed 466 insns (limit 1000000) max_states_per_insn 2 total_states 20 peak_states 20 mark_read 3
If we add this line, as used in other BPF programs, to cap that index:
index &= 7;
The generated BPF program is considered safe by that version of the BPF
verifier, allowing perf to collect the syscall args in one more kernel
using the BPF based pointer contents collector.
With the above one-liner it works with that kernel:
[root@dell-per740-01 ~]# uname -a
Linux dell-per740-01.khw.eng.rdu2.dc.redhat.com 4.18.0-513.11.1.el8_9.x86_64 #1 SMP Thu Dec 7 03:06:13 EST 2023 x86_64 x86_64 x86_64 GNU/Linux
[root@dell-per740-01 ~]# ~acme/bin/perf trace -e *sleep* sleep 1.234567890
0.000 (1234.704 ms): sleep/3863610 nanosleep(rqtp: { .tv_sec: 1, .tv_nsec: 234567890 }) = 0
[root@dell-per740-01 ~]#
As well as with the one in Fedora 40:
root@number:~# uname -a
Linux number 6.11.3-200.fc40.x86_64 #1 SMP PREEMPT_DYNAMIC Thu Oct 10 22:31:19 UTC 2024 x86_64 GNU/Linux
root@number:~# perf trace -e *sleep* sleep 1.234567890
0.000 (1234.722 ms): sleep/14873 clock_nanosleep(rqtp: { .tv_sec: 1, .tv_nsec: 234567890 }, rmtp: 0x7ffe87311a40) = 0
root@number:~#
Song Liu reported that this one-liner was being optimized out by clang
18, so I suggested and he tested that adding a compiler barrier before
it made clang v18 to keep it and the verifier in the kernel in Song's
case (Meta's 5.12 based kernel) also was happy with the resulting
bytecode.
I'll investigate using virtme-ng[1] to have all the perf BPF based
functionality thoroughly tested over multiple kernels and clang
versions.
[1] https://kernel-recipes.org/en/2024/virtme-ng/
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alan Maguire <alan.maguire@oracle.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andrea Righi <andrea.righi@linux.dev>
Cc: Howard Chu <howardchu95@gmail.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@linaro.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/lkml/Zw7JgJc0LOwSpuvx@x1
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
|
||
|
Howard Chu
|
a68fd6a6cd |
perf trace: Collect augmented data using BPF
Include trace_augment.h for TRACE_AUG_MAX_BUF, so that BPF reads TRACE_AUG_MAX_BUF bytes of buffer maximum. Determine what type of argument and how many bytes to read from user space, us ing the value in the beauty_map. This is the relation of parameter type and its corres ponding value in the beauty map, and how many bytes we read eventually: string: 1 -> size of string (till null) struct: size of struct -> size of struct buffer: -1 * (index of paired len) -> value of paired len (maximum: TRACE_AUG_ MAX_BUF) After reading from user space, we output the augmented data using bpf_perf_event_output(). If the struct augmenter, augment_sys_enter() failed, we fall back to using bpf_tail_call(). I have to make the payload 6 times the size of augmented_arg, to pass the BPF verifier. Signed-off-by: Howard Chu <howardchu95@gmail.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Namhyung Kim <namhyung@kernel.org> Link: https://lore.kernel.org/r/20240815013626.935097-10-howardchu95@gmail.com Link: https://lore.kernel.org/r/20240824163322.60796-7-howardchu95@gmail.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> |
||
|
Howard Chu
|
7f40306728 |
perf trace: Add trace__bpf_sys_enter_beauty_map() to prepare for fetching data in BPF
Set up beauty_map, load it to BPF, in such format: if argument No.3 is a
struct of size 32 bytes (of syscall number 114) beauty_map[114][2] = 32;
if argument No.3 is a string (of syscall number 114) beauty_map[114][2] =
1;
if argument No.3 is a buffer, its size is indicated by argument No.4 (of
syscall number 114) beauty_map[114][2] = -4; /* -1 ~ -6, we'll read this
buffer size in BPF */
Committer notes:
Moved syscall_arg_fmt__cache_btf_struct() from a ifdef
HAVE_LIBBPF_SUPPORT to closer to where it is used, that is ifdef'ed on
HAVE_BPF_SKEL and thus breaks the build when building with
BUILD_BPF_SKEL=0, as detected using 'make -C tools/perf build-test'.
Also add 'struct beauty_map_enter' to tools/perf/util/bpf_skel/augmented_raw_syscalls.bpf.c
as we're using it in this patch, otherwise we get this while trying to
build at this point in the original patch series:
builtin-trace.c: In function ‘trace__init_syscalls_bpf_prog_array_maps’:
builtin-trace.c:3725:58: error: ‘struct <anonymous>’ has no member named ‘beauty_map_enter’
3725 | int beauty_map_fd = bpf_map__fd(trace->skel->maps.beauty_map_enter);
|
We also have to take into account syscall_arg_fmt.from_user when telling
the kernel what to copy in the sys_enter generic collector, we don't
want to collect bogus data in buffers that will only be available to us
at sys_exit time, i.e. after the kernel has filled it, so leave this for
when we have such a sys_exit based collector.
Committer testing:
Not wired up yet, so all continues to work, using the existing BPF
collector and userspace beautifiers that are augmentation aware:
root@number:~# rm -f 987654 ; touch 123456 ; perf trace -e rename* mv 123456 987654
0.000 ( 0.031 ms): mv/20888 renameat2(olddfd: CWD, oldname: "123456", newdfd: CWD, newname: "987654", flags: NOREPLACE) = 0
root@number:~# perf trace -e connect,sendto ping -c 1 www.google.com
0.000 ( 0.014 ms): ping/20892 connect(fd: 5, uservaddr: { .family: LOCAL, path: /run/systemd/resolve/io.systemd.Resolve }, addrlen: 42) = 0
0.040 ( 0.003 ms): ping/20892 sendto(fd: 5, buff: 0x560b4ff17980, len: 97, flags: DONTWAIT|NOSIGNAL) = 97
0.480 ( 0.017 ms): ping/20892 sendto(fd: 5, buff: 0x7ffd82d07150, len: 20, addr: { .family: NETLINK }, addr_len: 0xc) = 20
0.526 ( 0.014 ms): ping/20892 connect(fd: 5, uservaddr: { .family: INET6, port: 0, addr: 2800:3f0:4004:810::2004 }, addrlen: 28) = 0
0.542 ( 0.002 ms): ping/20892 connect(fd: 5, uservaddr: { .family: UNSPEC }, addrlen: 16) = 0
0.544 ( 0.004 ms): ping/20892 connect(fd: 5, uservaddr: { .family: INET, port: 0, addr: 142.251.135.100 }, addrlen: 16) = 0
0.559 ( 0.002 ms): ping/20892 connect(fd: 5, uservaddr: { .family: INET, port: 1025, addr: 142.251.135.100 }, addrlen: 16PING www.google.com (142.251.135.100) 56(84) bytes of data.
) = 0
0.589 ( 0.058 ms): ping/20892 sendto(fd: 3, buff: 0x560b4ff11ac0, len: 64, addr: { .family: INET, port: 0, addr: 142.251.135.100 }, addr_len: 0x10) = 64
45.250 ( 0.029 ms): ping/20892 connect(fd: 5, uservaddr: { .family: LOCAL, path: /run/systemd/resolve/io.systemd.Resolve }, addrlen: 42) = 0
45.344 ( 0.012 ms): ping/20892 sendto(fd: 5, buff: 0x560b4ff19340, len: 111, flags: DONTWAIT|NOSIGNAL) = 111
64 bytes from rio09s08-in-f4.1e100.net (142.251.135.100): icmp_seq=1 ttl=49 time=44.4 ms
--- www.google.com ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 44.361/44.361/44.361/0.000 ms
root@number:~#
Signed-off-by: Howard Chu <howardchu95@gmail.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20240815013626.935097-4-howardchu95@gmail.com
Link: https://lore.kernel.org/r/20240824163322.60796-3-howardchu95@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
|
||
|
Arnaldo Carvalho de Melo
|
c90a88d33a |
perf trace: Use a common encoding for augmented arguments, with size + error + payload
We were using a more compact format, without explicitely encoding the
size and possible error in the payload for an argument.
To do it generically, at least as Howard Chu did in his GSoC activities,
it is more convenient to use the same model that was being used for
string arguments, passing { size, error, payload }.
So use that for the non string syscall args we have so far:
struct timespec
struct perf_event_attr
struct sockaddr (this one has even a variable size)
With this in place we have the userspace pretty printers:
perf_event_attr___scnprintf()
syscall_arg__scnprintf_augmented_sockaddr()
syscall_arg__scnprintf_augmented_timespec()
Ready to have the generic BPF collector in tools/perf/util/bpf_skel/augmented_raw_syscalls.bpf.c
sending its generic payload and thus we'll use them instead of a generic
libbpf btf_dump interface that doesn't know about about the sockaddr
mux, perf_event_attr non-trivial fields (sample_type, etc), leaving it
as a (useful) fallback that prints just basic types until we put in
place a more sophisticated pretty printer infrastructure that associates
synthesized enums to struct fields using the header scrapers we have in
tools/perf/trace/beauty/, some of them in this list:
$ ls tools/perf/trace/beauty/*.sh
tools/perf/trace/beauty/arch_errno_names.sh
tools/perf/trace/beauty/kcmp_type.sh
tools/perf/trace/beauty/perf_ioctl.sh
tools/perf/trace/beauty/statx_mask.sh
tools/perf/trace/beauty/clone.sh
tools/perf/trace/beauty/kvm_ioctl.sh
tools/perf/trace/beauty/pkey_alloc_access_rights.sh
tools/perf/trace/beauty/sync_file_range.sh
tools/perf/trace/beauty/drm_ioctl.sh
tools/perf/trace/beauty/madvise_behavior.sh
tools/perf/trace/beauty/prctl_option.sh
tools/perf/trace/beauty/usbdevfs_ioctl.sh
tools/perf/trace/beauty/fadvise.sh
tools/perf/trace/beauty/mmap_flags.sh
tools/perf/trace/beauty/rename_flags.sh
tools/perf/trace/beauty/vhost_virtio_ioctl.sh
tools/perf/trace/beauty/fs_at_flags.sh
tools/perf/trace/beauty/mmap_prot.sh
tools/perf/trace/beauty/sndrv_ctl_ioctl.sh
tools/perf/trace/beauty/x86_arch_prctl.sh
tools/perf/trace/beauty/fsconfig.sh
tools/perf/trace/beauty/mount_flags.sh
tools/perf/trace/beauty/sndrv_pcm_ioctl.sh
tools/perf/trace/beauty/fsmount.sh
tools/perf/trace/beauty/move_mount_flags.sh
tools/perf/trace/beauty/sockaddr.sh
tools/perf/trace/beauty/fspick.sh
tools/perf/trace/beauty/mremap_flags.sh
tools/perf/trace/beauty/socket.sh
$
Testing it:
root@number:~# rm -f 987654 ; touch 123456 ; perf trace -e rename* mv 123456 987654
0.000 ( 0.031 ms): mv/1193096 renameat2(olddfd: CWD, oldname: "123456", newdfd: CWD, newname: "987654", flags: NOREPLACE) = 0
root@number:~# perf trace -e *nanosleep sleep 1.2345678901
0.000 (1234.654 ms): sleep/1192697 clock_nanosleep(rqtp: { .tv_sec: 1, .tv_nsec: 234567891 }, rmtp: 0x7ffe1ea80460) = 0
root@number:~# perf trace -e perf_event_open* perf stat -e cpu-clock sleep 1
0.000 ( 0.011 ms): perf/1192701 perf_event_open(attr_uptr: { type: 1 (software), size: 136, config: 0 (PERF_COUNT_SW_CPU_CLOCK), sample_type: IDENTIFIER, read_format: TOTAL_TIME_ENABLED|TOTAL_TIME_RUNNING, disabled: 1, inherit: 1, enable_on_exec: 1, exclude_guest: 1 }, pid: 1192702 (perf), cpu: -1, group_fd: -1, flags: FD_CLOEXEC) = 3
Performance counter stats for 'sleep 1':
0.51 msec cpu-clock # 0.001 CPUs utilized
1.001242090 seconds time elapsed
0.000000000 seconds user
0.001010000 seconds sys
root@number:~# perf trace -e connect* ping -c 1 bsky.app
0.000 ( 0.130 ms): ping/1192740 connect(fd: 5, uservaddr: { .family: LOCAL, path: /run/systemd/resolve/io.systemd.Resolve }, addrlen: 42) = 0
23.907 ( 0.006 ms): ping/1192740 connect(fd: 5, uservaddr: { .family: INET, port: 0, addr: 3.20.108.158 }, addrlen: 16) = 0
23.915 PING bsky.app (3.20.108.158) 56(84) bytes of data.
( 0.001 ms): ping/1192740 connect(fd: 5, uservaddr: { .family: UNSPEC }, addrlen: 16) = 0
23.917 ( 0.002 ms): ping/1192740 connect(fd: 5, uservaddr: { .family: INET, port: 0, addr: 3.12.170.30 }, addrlen: 16) = 0
23.921 ( 0.001 ms): ping/1192740 connect(fd: 5, uservaddr: { .family: UNSPEC }, addrlen: 16) = 0
23.923 ( 0.001 ms): ping/1192740 connect(fd: 5, uservaddr: { .family: INET, port: 0, addr: 18.217.70.179 }, addrlen: 16) = 0
23.925 ( 0.001 ms): ping/1192740 connect(fd: 5, uservaddr: { .family: UNSPEC }, addrlen: 16) = 0
23.927 ( 0.001 ms): ping/1192740 connect(fd: 5, uservaddr: { .family: INET, port: 0, addr: 3.132.20.46 }, addrlen: 16) = 0
23.930 ( 0.001 ms): ping/1192740 connect(fd: 5, uservaddr: { .family: UNSPEC }, addrlen: 16) = 0
23.931 ( 0.001 ms): ping/1192740 connect(fd: 5, uservaddr: { .family: INET, port: 0, addr: 3.142.89.165 }, addrlen: 16) = 0
23.934 ( 0.001 ms): ping/1192740 connect(fd: 5, uservaddr: { .family: UNSPEC }, addrlen: 16) = 0
23.935 ( 0.002 ms): ping/1192740 connect(fd: 5, uservaddr: { .family: INET, port: 0, addr: 18.119.147.159 }, addrlen: 16) = 0
23.938 ( 0.001 ms): ping/1192740 connect(fd: 5, uservaddr: { .family: UNSPEC }, addrlen: 16) = 0
23.940 ( 0.001 ms): ping/1192740 connect(fd: 5, uservaddr: { .family: INET, port: 0, addr: 3.22.38.164 }, addrlen: 16) = 0
23.942 ( 0.001 ms): ping/1192740 connect(fd: 5, uservaddr: { .family: UNSPEC }, addrlen: 16) = 0
23.944 ( 0.001 ms): ping/1192740 connect(fd: 5, uservaddr: { .family: INET, port: 0, addr: 3.13.14.133 }, addrlen: 16) = 0
23.956 ( 0.001 ms): ping/1192740 connect(fd: 5, uservaddr: { .family: INET, port: 1025, addr: 3.20.108.158 }, addrlen: 16) = 0
^C
--- bsky.app ping statistics ---
1 packets transmitted, 0 received, 100% packet loss, time 0ms
root@number:~#
Reviewed-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Howard Chu <howardchu95@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/lkml/CAP-5=fW4=2GoP6foAN6qbrCiUzy0a_TzHbd8rvDsakTPfdzvfg@mail.gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
|
||
|
Arnaldo Carvalho de Melo
|
c1632cc5ed |
perf trace augmented_syscalls.bpf: Move the renameat aumenter to renameat2, temporarily
While trying to shape Howard Chu's generic BPF augmenter transition into
the codebase I got stuck with the renameat2 syscall.
Until I noticed that the attempt at reusing augmenters were making it
use the 'openat' syscall augmenter, that collect just one string syscall
arg, for the 'renameat2' syscall, that takes two strings.
So, for the moment, just to help in this transition period, since
'renameat2' is what is used these days in the 'mv' utility, just make
the BPF collector be associated with the more widely used syscall,
hopefully the transition to Howard's generic BPF augmenter will cure
this, so get this out of the way for now!
So now we still have that odd "reuse", but for something we're not
testing so won't get in the way anymore:
root@number:~# rm -f 987654 ; touch 123456 ; perf trace -vv -e rename* mv 123456 987654 |& grep renameat
Reusing "openat" BPF sys_enter augmenter for "renameat"
0.000 ( 0.079 ms): mv/1158612 renameat2(olddfd: CWD, oldname: "123456", newdfd: CWD, newname: "987654", flags: NOREPLACE) = 0
root@number:~#
Reviewed-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Howard Chu <howardchu95@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/lkml/CAP-5=fXjGYs=tpBgETK-P9U-CuXssytk9pSnTXpfphrmmOydWA@mail.gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
|
||
|
Namhyung Kim
|
8b3b1bb3ea |
perf record offcpu: Constify control data for BPF
The control knobs set before loading BPF programs should be declared as
'const volatile' so that it can be optimized by the BPF core.
Committer testing:
root@x1:~# perf record --off-cpu
^C[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 1.807 MB perf.data (5645 samples) ]
root@x1:~# perf evlist
cpu_atom/cycles/P
cpu_core/cycles/P
offcpu-time
dummy:u
root@x1:~# perf evlist -v
cpu_atom/cycles/P: type: 0 (PERF_TYPE_HARDWARE), size: 136, config: 0xa00000000, { sample_period, sample_freq }: 4000, sample_type: IP|TID|TIME|CPU|PERIOD|IDENTIFIER, read_format: ID|LOST, disabled: 1, inherit: 1, freq: 1, precise_ip: 3, sample_id_all: 1
cpu_core/cycles/P: type: 0 (PERF_TYPE_HARDWARE), size: 136, config: 0x400000000, { sample_period, sample_freq }: 4000, sample_type: IP|TID|TIME|CPU|PERIOD|IDENTIFIER, read_format: ID|LOST, disabled: 1, inherit: 1, freq: 1, precise_ip: 3, sample_id_all: 1
offcpu-time: type: 1 (software), size: 136, config: 0xa (PERF_COUNT_SW_BPF_OUTPUT), { sample_period, sample_freq }: 1, sample_type: IP|TID|TIME|CALLCHAIN|CPU|PERIOD|IDENTIFIER, read_format: ID|LOST, disabled: 1, inherit: 1, freq: 1, sample_id_all: 1
dummy:u: type: 1 (software), size: 136, config: 0x9 (PERF_COUNT_SW_DUMMY), { sample_period, sample_freq }: 1, sample_type: IP|TID|TIME|CPU|IDENTIFIER, read_format: ID|LOST, inherit: 1, exclude_kernel: 1, exclude_hv: 1, mmap: 1, comm: 1, task: 1, sample_id_all: 1, exclude_guest: 1, mmap2: 1, comm_exec: 1, ksymbol: 1, bpf_event: 1
root@x1:~# perf trace -e bpf --max-events 5 perf record --off-cpu
0.000 ( 0.015 ms): :2949124/2949124 bpf(cmd: 36, uattr: 0x7ffefc6dbe30, size: 8) = -1 EOPNOTSUPP (Operation not supported)
0.031 ( 0.115 ms): :2949124/2949124 bpf(cmd: PROG_LOAD, uattr: 0x7ffefc6dbb60, size: 148) = 14
0.159 ( 0.037 ms): :2949124/2949124 bpf(cmd: PROG_LOAD, uattr: 0x7ffefc6dbc20, size: 148) = 14
23.868 ( 0.144 ms): perf/2949124 bpf(cmd: PROG_LOAD, uattr: 0x7ffefc6dbad0, size: 148) = 14
24.027 ( 0.014 ms): perf/2949124 bpf(uattr: 0x7ffefc6dbc80, size: 80) = 14
root@x1:~#
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: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240902200515.2103769-6-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
|
||
|
Namhyung Kim
|
4afdc00c37 |
perf lock contention: Constify control data for BPF
The control knobs set before loading BPF programs should be declared as
'const volatile' so that it can be optimized by the BPF core.
Committer testing:
root@x1:~# perf lock contention --use-bpf
contended total wait max wait avg wait type caller
5 31.57 us 14.93 us 6.31 us mutex btrfs_delayed_update_inode+0x43
1 16.91 us 16.91 us 16.91 us rwsem:R btrfs_tree_read_lock_nested+0x1b
1 15.13 us 15.13 us 15.13 us spinlock btrfs_getattr+0xd1
1 6.65 us 6.65 us 6.65 us rwsem:R btrfs_tree_read_lock_nested+0x1b
1 4.34 us 4.34 us 4.34 us spinlock process_one_work+0x1a9
root@x1:~#
root@x1:~# perf trace -e bpf --max-events 10 perf lock contention --use-bpf
0.000 ( 0.013 ms): :2948281/2948281 bpf(cmd: 36, uattr: 0x7ffd5f12d730, size: 8) = -1 EOPNOTSUPP (Operation not supported)
0.024 ( 0.120 ms): :2948281/2948281 bpf(cmd: PROG_LOAD, uattr: 0x7ffd5f12d460, size: 148) = 16
0.158 ( 0.034 ms): :2948281/2948281 bpf(cmd: PROG_LOAD, uattr: 0x7ffd5f12d520, size: 148) = 16
26.653 ( 0.154 ms): perf/2948281 bpf(cmd: PROG_LOAD, uattr: 0x7ffd5f12d3d0, size: 148) = 16
26.825 ( 0.014 ms): perf/2948281 bpf(uattr: 0x7ffd5f12d580, size: 80) = 16
87.924 ( 0.038 ms): perf/2948281 bpf(cmd: BTF_LOAD, uattr: 0x7ffd5f12d400, size: 40) = 16
87.988 ( 0.006 ms): perf/2948281 bpf(cmd: BTF_LOAD, uattr: 0x7ffd5f12d470, size: 40) = 16
88.019 ( 0.006 ms): perf/2948281 bpf(cmd: BTF_LOAD, uattr: 0x7ffd5f12d250, size: 40) = 16
88.029 ( 0.172 ms): perf/2948281 bpf(cmd: PROG_LOAD, uattr: 0x7ffd5f12d320, size: 148) = 17
88.217 ( 0.005 ms): perf/2948281 bpf(cmd: BTF_LOAD, uattr: 0x7ffd5f12d4d0, size: 40) = 16
root@x1:~#
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: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240902200515.2103769-5-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
|
||
|
Namhyung Kim
|
066fd84087 |
perf kwork: Constify control data for BPF
The control knobs set before loading BPF programs should be declared as
'const volatile' so that it can be optimized by the BPF core.
Committer testing:
root@x1:~# perf kwork report --use-bpf
Starting trace, Hit <Ctrl+C> to stop and report
^C
Kwork Name | Cpu | Total Runtime | Count | Max runtime | Max runtime start | Max runtime end |
--------------------------------------------------------------------------------------------------------------------------------
(w)intel_atomic_commit_work [ | 0009 | 18.680 ms | 2 | 18.553 ms | 362410.681580 s | 362410.700133 s |
(w)pm_runtime_work | 0007 | 13.300 ms | 1 | 13.300 ms | 362410.254996 s | 362410.268295 s |
(w)intel_atomic_commit_work [ | 0009 | 9.846 ms | 2 | 9.717 ms | 362410.172352 s | 362410.182069 s |
(w)acpi_ec_event_processor | 0002 | 8.106 ms | 1 | 8.106 ms | 362410.463187 s | 362410.471293 s |
(s)SCHED:7 | 0000 | 1.351 ms | 106 | 0.063 ms | 362410.658017 s | 362410.658080 s |
i915:157 | 0008 | 0.994 ms | 13 | 0.361 ms | 362411.222125 s | 362411.222486 s |
(s)SCHED:7 | 0001 | 0.703 ms | 98 | 0.047 ms | 362410.245004 s | 362410.245051 s |
(s)SCHED:7 | 0005 | 0.674 ms | 42 | 0.074 ms | 362411.483039 s | 362411.483113 s |
(s)NET_RX:3 | 0001 | 0.556 ms | 10 | 0.079 ms | 362411.066388 s | 362411.066467 s |
<SNIP>
root@x1:~# perf trace -e bpf --max-events 5 perf kwork report --use-bpf
0.000 ( 0.016 ms): perf/2948007 bpf(cmd: 36, uattr: 0x7ffededa6660, size: 8) = -1 EOPNOTSUPP (Operation not supported)
0.026 ( 0.106 ms): perf/2948007 bpf(cmd: PROG_LOAD, uattr: 0x7ffededa6390, size: 148) = 12
0.152 ( 0.032 ms): perf/2948007 bpf(cmd: PROG_LOAD, uattr: 0x7ffededa6450, size: 148) = 12
26.247 ( 0.138 ms): perf/2948007 bpf(cmd: PROG_LOAD, uattr: 0x7ffededa6300, size: 148) = 12
26.396 ( 0.012 ms): perf/2948007 bpf(uattr: 0x7ffededa64b0, size: 80) = 12
Starting trace, Hit <Ctrl+C> to stop and report
root@x1:~#
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: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <song@kernel.org>
Cc: Yang Jihong <yangjihong@bytedance.com>
Link: https://lore.kernel.org/r/20240902200515.2103769-4-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
|
||
|
Namhyung Kim
|
ac5a23b2f2 |
perf ftrace latency: Constify control data for BPF
The control knobs set before loading BPF programs should be declared as
'const volatile' so that it can be optimized by the BPF core.
Committer testing:
root@x1:~# perf ftrace latency --use-bpf -T schedule
^C# DURATION | COUNT | GRAPH |
0 - 1 us | 0 | |
1 - 2 us | 0 | |
2 - 4 us | 0 | |
4 - 8 us | 0 | |
8 - 16 us | 1 | |
16 - 32 us | 5 | |
32 - 64 us | 2 | |
64 - 128 us | 6 | |
128 - 256 us | 7 | |
256 - 512 us | 5 | |
512 - 1024 us | 22 | # |
1 - 2 ms | 36 | ## |
2 - 4 ms | 68 | ##### |
4 - 8 ms | 22 | # |
8 - 16 ms | 91 | ####### |
16 - 32 ms | 11 | |
32 - 64 ms | 26 | ## |
64 - 128 ms | 213 | ################# |
128 - 256 ms | 19 | # |
256 - 512 ms | 14 | # |
512 - 1024 ms | 5 | |
1 - ... s | 8 | |
root@x1:~#
root@x1:~# perf trace -e bpf perf ftrace latency --use-bpf -T schedule
0.000 ( 0.015 ms): perf/2944525 bpf(cmd: 36, uattr: 0x7ffe80de7b40, size: 8) = -1 EOPNOTSUPP (Operation not supported)
0.025 ( 0.102 ms): perf/2944525 bpf(cmd: PROG_LOAD, uattr: 0x7ffe80de7870, size: 148) = 8
0.136 ( 0.026 ms): perf/2944525 bpf(cmd: PROG_LOAD, uattr: 0x7ffe80de7930, size: 148) = 8
0.174 ( 0.026 ms): perf/2944525 bpf(cmd: PROG_LOAD, uattr: 0x7ffe80de77e0, size: 148) = 8
0.205 ( 0.010 ms): perf/2944525 bpf(uattr: 0x7ffe80de7990, size: 80) = 8
0.227 ( 0.011 ms): perf/2944525 bpf(cmd: BTF_LOAD, uattr: 0x7ffe80de7810, size: 40) = 8
0.244 ( 0.004 ms): perf/2944525 bpf(cmd: BTF_LOAD, uattr: 0x7ffe80de7880, size: 40) = 8
0.257 ( 0.006 ms): perf/2944525 bpf(cmd: BTF_LOAD, uattr: 0x7ffe80de7660, size: 40) = 8
0.265 ( 0.058 ms): perf/2944525 bpf(cmd: PROG_LOAD, uattr: 0x7ffe80de7730, size: 148) = 9
0.330 ( 0.004 ms): perf/2944525 bpf(cmd: BTF_LOAD, uattr: 0x7ffe80de78e0, size: 40) = 8
0.337 ( 0.003 ms): perf/2944525 bpf(cmd: BTF_LOAD, uattr: 0x7ffe80de7890, size: 40) = 8
0.343 ( 0.004 ms): perf/2944525 bpf(cmd: BTF_LOAD, uattr: 0x7ffe80de7880, size: 40) = 8
0.349 ( 0.003 ms): perf/2944525 bpf(cmd: BTF_LOAD, uattr: 0x7ffe80de78b0, size: 40) = 8
0.355 ( 0.004 ms): perf/2944525 bpf(cmd: BTF_LOAD, uattr: 0x7ffe80de7890, size: 40) = 8
0.361 ( 0.003 ms): perf/2944525 bpf(cmd: BTF_LOAD, uattr: 0x7ffe80de78b0, size: 40) = 8
0.367 ( 0.003 ms): perf/2944525 bpf(cmd: BTF_LOAD, uattr: 0x7ffe80de7880, size: 40) = 8
0.373 ( 0.014 ms): perf/2944525 bpf(cmd: BTF_LOAD, uattr: 0x7ffe80de7a00, size: 40) = 8
0.390 ( 0.358 ms): perf/2944525 bpf(uattr: 0x7ffe80de7950, size: 80) = 9
0.763 ( 0.014 ms): perf/2944525 bpf(uattr: 0x7ffe80de7950, size: 80) = 9
0.783 ( 0.011 ms): perf/2944525 bpf(uattr: 0x7ffe80de7950, size: 80) = 9
0.798 ( 0.017 ms): perf/2944525 bpf(uattr: 0x7ffe80de7950, size: 80) = 9
0.819 ( 0.003 ms): perf/2944525 bpf(uattr: 0x7ffe80de7700, size: 80) = 9
0.824 ( 0.047 ms): perf/2944525 bpf(cmd: PROG_LOAD, uattr: 0x7ffe80de76c0, size: 148) = 10
0.878 ( 0.008 ms): perf/2944525 bpf(uattr: 0x7ffe80de7950, size: 80) = 9
0.891 ( 0.014 ms): perf/2944525 bpf(cmd: MAP_UPDATE_ELEM, uattr: 0x7ffe80de79e0, size: 32) = 0
0.910 ( 0.103 ms): perf/2944525 bpf(cmd: PROG_LOAD, uattr: 0x7ffe80de7880, size: 148) = 9
1.016 ( 0.143 ms): perf/2944525 bpf(cmd: PROG_LOAD, uattr: 0x7ffe80de7880, size: 148) = 10
3.777 ( 0.068 ms): perf/2944525 bpf(cmd: PROG_LOAD, uattr: 0x7ffe80de7570, size: 148) = 12
3.848 ( 0.003 ms): perf/2944525 bpf(cmd: LINK_CREATE, uattr: 0x7ffe80de7550, size: 64) = -1 EBADF (Bad file descriptor)
3.859 ( 0.006 ms): perf/2944525 bpf(cmd: LINK_CREATE, uattr: 0x7ffe80de77c0, size: 64) = 12
6.504 ( 0.010 ms): perf/2944525 bpf(cmd: LINK_CREATE, uattr: 0x7ffe80de77c0, size: 64) = 14
^C# DURATION | COUNT | GRAPH |
0 - 1 us | 0 | |
1 - 2 us | 0 | |
2 - 4 us | 1 | |
4 - 8 us | 3 | |
8 - 16 us | 3 | |
16 - 32 us | 11 | |
32 - 64 us | 9 | |
64 - 128 us | 17 | |
128 - 256 us | 30 | # |
256 - 512 us | 20 | |
512 - 1024 us | 42 | # |
1 - 2 ms | 151 | ###### |
2 - 4 ms | 106 | #### |
4 - 8 ms | 18 | |
8 - 16 ms | 149 | ###### |
16 - 32 ms | 30 | # |
32 - 64 ms | 17 | |
64 - 128 ms | 360 | ############### |
128 - 256 ms | 52 | ## |
256 - 512 ms | 18 | |
512 - 1024 ms | 28 | # |
1 - ... s | 5 | |
root@x1:~#
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: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240902200515.2103769-3-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
|
||
|
Namhyung Kim
|
76d3685400 |
perf stat: Constify control data for BPF
The control knobs set before loading BPF programs should be declared as
'const volatile' so that it can be optimized by the BPF core.
Committer testing:
root@x1:~# perf stat --bpf-counters -e cpu_core/cycles/,cpu_core/instructions/ sleep 1
Performance counter stats for 'sleep 1':
2,442,583 cpu_core/cycles/
2,494,425 cpu_core/instructions/
1.002687372 seconds time elapsed
0.001126000 seconds user
0.001166000 seconds sys
root@x1:~# perf trace -e bpf --max-events 10 perf stat --bpf-counters -e cpu_core/cycles/,cpu_core/instructions/ sleep 1
0.000 ( 0.019 ms): perf/2944119 bpf(cmd: OBJ_GET, uattr: 0x7fffdf5cdd40, size: 20) = 5
0.021 ( 0.002 ms): perf/2944119 bpf(cmd: OBJ_GET_INFO_BY_FD, uattr: 0x7fffdf5cdcd0, size: 16) = 0
0.030 ( 0.005 ms): perf/2944119 bpf(cmd: MAP_LOOKUP_ELEM, uattr: 0x7fffdf5ceda0, size: 32) = 0
0.037 ( 0.004 ms): perf/2944119 bpf(cmd: LINK_GET_FD_BY_ID, uattr: 0x7fffdf5ced80, size: 12) = -1 ENOENT (No such file or directory)
0.189 ( 0.004 ms): perf/2944119 bpf(cmd: 36, uattr: 0x7fffdf5cec10, size: 8) = -1 EOPNOTSUPP (Operation not supported)
0.201 ( 0.095 ms): perf/2944119 bpf(cmd: PROG_LOAD, uattr: 0x7fffdf5ce940, size: 148) = 10
0.305 ( 0.026 ms): perf/2944119 bpf(cmd: PROG_LOAD, uattr: 0x7fffdf5cea00, size: 148) = 10
0.347 ( 0.012 ms): perf/2944119 bpf(cmd: BTF_LOAD, uattr: 0x7fffdf5ce8e0, size: 40) = 10
0.364 ( 0.004 ms): perf/2944119 bpf(cmd: BTF_LOAD, uattr: 0x7fffdf5ce950, size: 40) = 10
0.376 ( 0.006 ms): perf/2944119 bpf(cmd: BTF_LOAD, uattr: 0x7fffdf5ce730, size: 40) = 10
root@x1:~#
Performance counter stats for 'sleep 1':
271,221 cpu_core/cycles/
139,150 cpu_core/instructions/
1.002881677 seconds time elapsed
0.001318000 seconds user
0.001314000 seconds sys
root@x1:~#
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: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240902200515.2103769-2-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
|
||
|
Namhyung Kim
|
36cddd1056 |
perf lock contention: Do not fail EEXIST for update
When it updates the lock stat for the first time, it needs to create an element in the BPF hash map. But if there's a concurrent thread waiting for the same lock (like for rwsem or rwlock), it might race with the thread and possibly fail to update with -EEXIST. In that case, it can lookup the map again and put the data there instead of failing. Signed-off-by: Namhyung Kim <namhyung@kernel.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Song Liu <song@kernel.org> Cc: bpf@vger.kernel.org Link: https://lore.kernel.org/r/20240830065150.1758962-3-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> |
||
|
Namhyung Kim
|
05a5dd1dfd |
perf lock contention: Simplify spinlock check
The LCB_F_SPIN bit is used for spinlock, rwlock and optimistic spinning in mutex. In get_tstamp_elem() it needs to check spinlock and rwlock only. As mutex sets the LCB_F_MUTEX, it can check those two bits and reduce the number of operations. Signed-off-by: Namhyung Kim <namhyung@kernel.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Song Liu <song@kernel.org> Cc: bpf@vger.kernel.org Link: https://lore.kernel.org/r/20240830065150.1758962-2-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> |
||
|
Namhyung Kim
|
10d6c57c82 |
perf lock contention: Handle error in a single place
It has some duplicate codes to do the same job. Let's add a label and goto there to handle errors in a single place. Signed-off-by: Namhyung Kim <namhyung@kernel.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Song Liu <song@kernel.org> Cc: bpf@vger.kernel.org Link: https://lore.kernel.org/r/20240830065150.1758962-1-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> |
||
|
Namhyung Kim
|
91e88437d5 |
perf bpf-filter: Support filtering on cgroups
The new cgroup filter can take either of '==' or '!=' operator and a pathname for the target cgroup. $ perf record -a --all-cgroups -e cycles --filter 'cgroup == /abc/def' -- sleep 1 Users should have --all-cgroups option in the command line to enable cgroup filtering. Technically it doesn't need to have the option as it can get the current task's cgroup info directly from BPF. But I want to follow the convention for the other sample info. Signed-off-by: Namhyung Kim <namhyung@kernel.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: https://lore.kernel.org/r/20240826221045.1202305-4-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> |
||
|
Namhyung Kim
|
0fe2b18ddc |
perf bpf-filter: Support multiple events properly
So far it used tgid as a key to get the filter expressions in the pinned filters map for regular users but it won't work well if the has more than one filters at the same time. Let's add the event id to the key of the filter hash map so that it can identify the right filter expression in the BPF program. As the event can be inherited to child tasks, it should use the primary id which belongs to the parent (original) event. Since evsel opens the event for multiple CPUs and tasks, it needs to maintain a separate hash map for the event id. In the user space, it keeps a list for the multiple evsel and release the entries in the both hash map when it closes the event. Signed-off-by: Namhyung Kim <namhyung@kernel.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jiri Olsa <jolsa@kernel.org> Cc: KP Singh <kpsingh@kernel.org> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20240820154504.128923-1-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> |
||
|
Namhyung Kim
|
040c0f887f |
perf lock contention: Change stack_id type to s32
The bpf_get_stackid() helper returns a signed type to check whether it
failed to get a stacktrace or not. But it saved the result in u32 and
checked if the value is negative.
376 if (needs_callstack) {
377 pelem->stack_id = bpf_get_stackid(ctx, &stacks,
378 BPF_F_FAST_STACK_CMP | stack_skip);
--> 379 if (pelem->stack_id < 0)
./tools/perf/util/bpf_skel/lock_contention.bpf.c:379 contention_begin()
warn: unsigned 'pelem->stack_id' is never less than zero.
Let's change the type to s32 instead.
Fixes:
|
||
|
Namhyung Kim
|
1ec6fd34e0 |
perf bpf-filter: Support separate lost counts for each filter
As the BPF filter is shared between other processes, it should have its own counter for each invocation. Add a new array map (lost_count) to save the count using the same index as the filter. It should clear the count before running the filter. Signed-off-by: Namhyung Kim <namhyung@kernel.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jiri Olsa <jolsa@kernel.org> Cc: KP Singh <kpsingh@kernel.org> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Song Liu <song@kernel.org> Cc: Stephane Eranian <eranian@google.com> Cc: bpf@vger.kernel.org Link: https://lore.kernel.org/r/20240703223035.2024586-6-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> |
||
|
Namhyung Kim
|
eb1693b115 |
perf bpf-filter: Split per-task filter use case
If the target is a list of tasks, it can use a shared hash map for filter expressions. The key of the filter map is an integer index like in an array. A separate pid_hash map is added to get the index for the filter map using the tgid. For system-wide mode including per-cpu or per-user targets are handled by the single entry map like before. Signed-off-by: Namhyung Kim <namhyung@kernel.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jiri Olsa <jolsa@kernel.org> Cc: KP Singh <kpsingh@kernel.org> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Song Liu <song@kernel.org> Cc: Stephane Eranian <eranian@google.com> Cc: bpf@vger.kernel.org Link: https://lore.kernel.org/r/20240703223035.2024586-4-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> |
||
|
Namhyung Kim
|
edb08cdd10 |
perf bpf-filter: Make filters map a single entry hashmap
And the value is now an array. This is to support multiple filter entries in the map later. No functional changes intended. Signed-off-by: Namhyung Kim <namhyung@kernel.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jiri Olsa <jolsa@kernel.org> Cc: KP Singh <kpsingh@kernel.org> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Song Liu <song@kernel.org> Cc: Stephane Eranian <eranian@google.com> Cc: bpf@vger.kernel.org Link: https://lore.kernel.org/r/20240703223035.2024586-2-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> |
||
Ian Rogers
|
d92aa899fe |
perf bpf filter: Add uid and gid terms
Allow the BPF filter to use the uid and gid terms determined by the bpf_get_current_uid_gid BPF helper. For example, the following will record the cpu-clock event system wide discarding samples that don't belong to the current user. $ perf record -e cpu-clock --filter "uid == $(id -u)" -a sleep 0.1 Signed-off-by: Ian Rogers <irogers@google.com> Acked-by: Namhyung Kim <namhyung@kernel.org> Cc: John Fastabend <john.fastabend@gmail.com> Cc: Changbin Du <changbin.du@huawei.com> Cc: Yang Jihong <yangjihong1@huawei.com> Cc: Andrii Nakryiko <andrii@kernel.org> Cc: bpf@vger.kernel.org Signed-off-by: Namhyung Kim <namhyung@kernel.org> Link: https://lore.kernel.org/r/20240524205227.244375-3-irogers@google.com |
||
|
Ian Rogers
|
63b9cbd794 |
perf bpf filter: Give terms their own enum
Give the term types their own enum so that additional terms can be added that don't correspond to a PERF_SAMPLE_xx flag. The term values are numerically ascending rather than bit field positions, this means they need translating to a PERF_SAMPLE_xx bit field in certain places using a shift. Signed-off-by: Ian Rogers <irogers@google.com> Acked-by: Namhyung Kim <namhyung@kernel.org> Cc: John Fastabend <john.fastabend@gmail.com> Cc: Changbin Du <changbin.du@huawei.com> Cc: Yang Jihong <yangjihong1@huawei.com> Cc: Andrii Nakryiko <andrii@kernel.org> Cc: bpf@vger.kernel.org Signed-off-by: Namhyung Kim <namhyung@kernel.org> Link: https://lore.kernel.org/r/20240524205227.244375-2-irogers@google.com |
||
|
Arnaldo Carvalho de Melo
|
173b0b5b0e |
Merge remote-tracking branch 'torvalds/master' into perf-tools-next
To pick up fixes sent via perf-tools, by Namhyung Kim. Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> |
||
|
Ian Rogers
|
988052f4bf |
perf bench uprobe: Add uretprobe variant of uprobe benchmarks
Name benchmarks with _ret at the end to avoid creating a new set of benchmarks. Signed-off-by: Ian Rogers <irogers@google.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andrei Vagin <avagin@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Kees Kook <keescook@chromium.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: https://lore.kernel.org/r/20240406040911.1603801-2-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> |
||
|
Namhyung Kim
|
f3408580ba |
perf lock contention: Add a missing NULL check
I got a report for a failure in BPF verifier on a recent kernel with
perf lock contention command. It checks task->sighand->siglock without
checking if sighand is NULL or not. Let's add one.
; if (&curr->sighand->siglock == (void *)lock)
265: (79) r1 = *(u64 *)(r0 +2624) ; frame1: R0_w=trusted_ptr_task_struct(off=0,imm=0)
; R1_w=rcu_ptr_or_null_sighand_struct(off=0,imm=0)
266: (b7) r2 = 0 ; frame1: R2_w=0
267: (0f) r1 += r2
R1 pointer arithmetic on rcu_ptr_or_null_ prohibited, null-check it first
processed 164 insns (limit 1000000) max_states_per_insn 1 total_states 15 peak_states 15 mark_read 5
-- END PROG LOAD LOG --
libbpf: prog 'contention_end': failed to load: -13
libbpf: failed to load object 'lock_contention_bpf'
libbpf: failed to load BPF skeleton 'lock_contention_bpf': -13
Failed to load lock-contention BPF skeleton
lock contention BPF setup failed
lock contention did not detect any lock contention
Fixes:
|
||
|
Arnaldo Carvalho de Melo
|
a9f4c6c999 |
perf trace: Collect sys_nanosleep first argument
That is a 'struct timespec' passed from userspace to the kernel as we
can see with a system wide syscall tracing:
root@number:~# perf trace -e nanosleep
0.000 (10.102 ms): podman/9150 nanosleep(rqtp: { .tv_sec: 0, .tv_nsec: 10000000 }) = 0
38.924 (10.077 ms): podman/2195174 nanosleep(rqtp: { .tv_sec: 0, .tv_nsec: 10000000 }) = 0
100.177 (10.107 ms): podman/9150 nanosleep(rqtp: { .tv_sec: 0, .tv_nsec: 10000000 }) = 0
139.171 (10.063 ms): podman/2195174 nanosleep(rqtp: { .tv_sec: 0, .tv_nsec: 10000000 }) = 0
200.603 (10.105 ms): podman/9150 nanosleep(rqtp: { .tv_sec: 0, .tv_nsec: 10000000 }) = 0
239.399 (10.064 ms): podman/2195174 nanosleep(rqtp: { .tv_sec: 0, .tv_nsec: 10000000 }) = 0
300.994 (10.096 ms): podman/9150 nanosleep(rqtp: { .tv_sec: 0, .tv_nsec: 10000000 }) = 0
339.584 (10.067 ms): podman/2195174 nanosleep(rqtp: { .tv_sec: 0, .tv_nsec: 10000000 }) = 0
401.335 (10.057 ms): podman/9150 nanosleep(rqtp: { .tv_sec: 0, .tv_nsec: 10000000 }) = 0
439.758 (10.166 ms): podman/2195174 nanosleep(rqtp: { .tv_sec: 0, .tv_nsec: 10000000 }) = 0
501.814 (10.110 ms): podman/9150 nanosleep(rqtp: { .tv_sec: 0, .tv_nsec: 10000000 }) = 0
539.983 (10.227 ms): podman/2195174 nanosleep(rqtp: { .tv_sec: 0, .tv_nsec: 10000000 }) = 0
602.284 (10.199 ms): podman/9150 nanosleep(rqtp: { .tv_sec: 0, .tv_nsec: 10000000 }) = 0
640.208 (10.105 ms): podman/2195174 nanosleep(rqtp: { .tv_sec: 0, .tv_nsec: 10000000 }) = 0
702.662 (10.163 ms): podman/9150 nanosleep(rqtp: { .tv_sec: 0, .tv_nsec: 10000000 }) = 0
740.440 (10.107 ms): podman/2195174 nanosleep(rqtp: { .tv_sec: 0, .tv_nsec: 10000000 }) = 0
802.993 (10.159 ms): podman/9150 nanosleep(rqtp: { .tv_sec: 0, .tv_nsec: 10000000 }) = 0
^Croot@number:~# strace -p 9150 -e nanosleep
If we then use the ptrace method to look at that podman process:
root@number:~# strace -p 9150 -e nanosleep
strace: Process 9150 attached
nanosleep({tv_sec=0, tv_nsec=10000000}, NULL) = 0
nanosleep({tv_sec=0, tv_nsec=10000000}, NULL) = 0
nanosleep({tv_sec=0, tv_nsec=10000000}, NULL) = 0
nanosleep({tv_sec=0, tv_nsec=10000000}, NULL) = 0
nanosleep({tv_sec=0, tv_nsec=10000000}, NULL) = 0
nanosleep({tv_sec=0, tv_nsec=10000000}, NULL) = 0
nanosleep({tv_sec=0, tv_nsec=10000000}, NULL) = 0
^Cstrace: Process 9150 detached
root@number:~#
With some changes we can get something closer to the strace output,
still in system wide mode:
root@number:~# perf config trace.show_arg_names=false
root@number:~# perf config trace.show_duration=false
root@number:~# perf config trace.show_timestamp=false
root@number:~# perf config trace.show_zeros=true
root@number:~# perf config trace.args_alignment=0
root@number:~# perf trace -e nanosleep --max-events=10
podman/2195174 nanosleep({ .tv_sec: 0, .tv_nsec: 10000000 }, NULL) = 0
podman/9150 nanosleep({ .tv_sec: 0, .tv_nsec: 10000000 }, NULL) = 0
podman/2195174 nanosleep({ .tv_sec: 0, .tv_nsec: 10000000 }, NULL) = 0
podman/9150 nanosleep({ .tv_sec: 0, .tv_nsec: 10000000 }, NULL) = 0
podman/2195174 nanosleep({ .tv_sec: 0, .tv_nsec: 10000000 }, NULL) = 0
podman/9150 nanosleep({ .tv_sec: 0, .tv_nsec: 10000000 }, NULL) = 0
podman/2195174 nanosleep({ .tv_sec: 0, .tv_nsec: 10000000 }, NULL) = 0
podman/9150 nanosleep({ .tv_sec: 0, .tv_nsec: 10000000 }, NULL) = 0
podman/2195174 nanosleep({ .tv_sec: 0, .tv_nsec: 10000000 }, NULL) = 0
podman/9150 nanosleep({ .tv_sec: 0, .tv_nsec: 10000000 }, NULL) = 0
root@number:~#
root@number:~# perf config
trace.show_arg_names=false
trace.show_duration=false
trace.show_timestamp=false
trace.show_zeros=true
trace.args_alignment=0
root@number:~# cat ~/.perfconfig
# this file is auto-generated.
[trace]
show_arg_names = false
show_duration = false
show_timestamp = false
show_zeros = true
args_alignment = 0
root@number:~#
This will not get reused by any other syscall as nanosleep is the only
one to have as its first argument a 'struct timespec" pointer argument
passed from userspace to the kernel:
root@number:~# grep timespec /sys/kernel/tracing/events/syscalls/sys_enter_*/format | grep offset:16
/sys/kernel/tracing/events/syscalls/sys_enter_nanosleep/format: field:struct __kernel_timespec * rqtp; offset:16; size:8; signed:0;
root@number:~#
BTF based pretty printing will simplify all this, but then lets just get
the low hanging fruits first.
Reviewed-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/lkml/Zbq72dJRpOlfRWnf@kernel.org/
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
|
||
|
Namhyung Kim
|
b44d665368 |
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
|
||
Arnaldo Carvalho de Melo
|
29d16de26d |
perf augmented_raw_syscalls.bpf: Move 'struct timespec64' to vmlinux.h
If we instead decide to generate vmlinux.h from BTF info, it will be
there:
$ pahole timespec64
struct timespec64 {
time64_t tv_sec; /* 0 8 */
long int tv_nsec; /* 8 8 */
/* size: 16, cachelines: 1, members: 2 */
/* last cacheline: 16 bytes */
};
$
pahole manages to find it from /sys/kernel/btf/vmlinux, that is
generated from the kernel types.
With this linux/bpf.h doesn't need to be included, as its already in the
minimalistic tools/perf/util/bpf_skel/vmlinux/vmlinux.h file or what we
need comes when generating a vmlinux.h file from BTF info, i.e. when
using GEN_VMLINUX_H=1, as noticed by Namyung in a build break before
removing linux/bpf.h.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/Zc_fp6CgDClPhS_O@x1
|
||
|
Namhyung Kim
|
b5711042a1 |
perf lock contention: Use per-cpu array map for spinlocks
Currently lock contention timestamp is maintained in a hash map keyed by pid. That means it needs to get and release a map element (which is proctected by spinlock!) on each contention begin and end pair. This can impact on performance if there are a lot of contention (usually from spinlocks). It used to go with task local storage but it had an issue on memory allocation in some critical paths. Although it's addressed in recent kernels IIUC, the tool should support old kernels too. So it cannot simply switch to the task local storage at least for now. As spinlocks create lots of contention and they disabled preemption during the spinning, it can use per-cpu array to keep the timestamp to avoid overhead in hashmap update and delete. In contention_begin, it's easy to check the lock types since it can see the flags. But contention_end cannot see it. So let's try to per-cpu array first (unconditionally) if it has an active element (lock != 0). Then it should be used and per-task tstamp map should not be used until the per-cpu array element is cleared which means nested spinlock contention (if any) was finished and it nows see (the outer) lock. Signed-off-by: Namhyung Kim <namhyung@kernel.org> Acked-by: Ian Rogers <irogers@google.com> Cc: Hao Luo <haoluo@google.com> Cc: Song Liu <song@kernel.org> Cc: bpf@vger.kernel.org Link: https://lore.kernel.org/r/20231020204741.1869520-3-namhyung@kernel.org |
||
|
Namhyung Kim
|
6a070573f2 |
perf lock contention: Check race in tstamp elem creation
When pelem is NULL, it'd create a new entry with zero data. But it might be preempted by IRQ/NMI just before calling bpf_map_update_elem() then there's a chance to call it twice for the same pid. So it'd be better to use BPF_NOEXIST flag and check the return value to prevent the race. Signed-off-by: Namhyung Kim <namhyung@kernel.org> Acked-by: Ian Rogers <irogers@google.com> Cc: Hao Luo <haoluo@google.com> Cc: Song Liu <song@kernel.org> Cc: bpf@vger.kernel.org Link: https://lore.kernel.org/r/20231020204741.1869520-2-namhyung@kernel.org |