An issue can be observed when probe C++ demangled symbol with steps:
# nm test_cpp_mangle | grep print_data
0000000000000c94 t _GLOBAL__sub_I__Z10print_datai
0000000000000afc T _Z10print_datai
0000000000000b38 T _Z10print_dataR5Point
# perf probe -x /home/niayan01/test_cpp_mangle -F --demangle
...
print_data(Point&)
print_data(int)
...
# perf --debug verbose=3 probe -x test_cpp_mangle --add "test=print_data(int)"
probe-definition(0): test=print_data(int)
symbol:print_data(int) file:(null) line:0 offset:0 return:0 lazy:(null)
0 arguments
Open Debuginfo file: /home/niayan01/test_cpp_mangle
Try to find probe point from debuginfo.
Symbol print_data(int) address found : afc
Matched function: print_data [2ccf]
Probe point found: print_data+0
Found 1 probe_trace_events.
Opening /sys/kernel/tracing//uprobe_events write=1
Opening /sys/kernel/tracing//README write=0
Writing event: p:probe_test_cpp_mangle/test /home/niayan01/test_cpp_mangle:0xb38
...
When tried to probe symbol "print_data(int)", the log shows:
Symbol print_data(int) address found : afc
The found address is 0xafc - which is right with verifying the output
result from nm. Afterwards when write event, the command uses offset
0xb38 in the last log, which is a wrong address.
The dwarf_diename() gets a common function name, in above case, it
returns string "print_data". As a result, the tool parses the offset
based on the common name. This leads to probe at the wrong symbol
"print_data(Point&)".
To fix the issue, use the die_get_linkage_name() function to retrieve
the distinct linkage name - this is the mangled name for the C++ case.
Based on this unique name, the tool can get a correct offset for
probing. Based on DWARF doc, it is possible the linkage name is missed
in the DIE, it rolls back to use dwarf_diename().
After:
# perf --debug verbose=3 probe -x test_cpp_mangle --add "test=print_data(int)"
probe-definition(0): test=print_data(int)
symbol:print_data(int) file:(null) line:0 offset:0 return:0 lazy:(null)
0 arguments
Open Debuginfo file: /home/niayan01/test_cpp_mangle
Try to find probe point from debuginfo.
Symbol print_data(int) address found : afc
Matched function: print_data [2d06]
Probe point found: print_data+0
Found 1 probe_trace_events.
Opening /sys/kernel/tracing//uprobe_events write=1
Opening /sys/kernel/tracing//README write=0
Writing event: p:probe_test_cpp_mangle/test /home/niayan01/test_cpp_mangle:0xafc
Added new event:
probe_test_cpp_mangle:test (on print_data(int) in /home/niayan01/test_cpp_mangle)
You can now use it in all perf tools, such as:
perf record -e probe_test_cpp_mangle:test -aR sleep 1
# perf --debug verbose=3 probe -x test_cpp_mangle --add "test2=print_data(Point&)"
probe-definition(0): test2=print_data(Point&)
symbol:print_data(Point&) file:(null) line:0 offset:0 return:0 lazy:(null)
0 arguments
Open Debuginfo file: /home/niayan01/test_cpp_mangle
Try to find probe point from debuginfo.
Symbol print_data(Point&) address found : b38
Matched function: print_data [2ccf]
Probe point found: print_data+0
Found 1 probe_trace_events.
Opening /sys/kernel/tracing//uprobe_events write=1
Parsing probe_events: p:probe_test_cpp_mangle/test /home/niayan01/test_cpp_mangle:0x0000000000000afc
Group:probe_test_cpp_mangle Event:test probe:p
Opening /sys/kernel/tracing//README write=0
Writing event: p:probe_test_cpp_mangle/test2 /home/niayan01/test_cpp_mangle:0xb38
Added new event:
probe_test_cpp_mangle:test2 (on print_data(Point&) in /home/niayan01/test_cpp_mangle)
You can now use it in all perf tools, such as:
perf record -e probe_test_cpp_mangle:test2 -aR sleep 1
Fixes: fb1587d869 ("perf probe: List probes with line number and file name")
Signed-off-by: Leo Yan <leo.yan@arm.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Link: https://lore.kernel.org/r/20241012141432.877894-1-leo.yan@arm.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
During the rework of the dso structure in patch ee756ef749 an
increment was forgotten for the symtab_type in case the data for
the kernel module are compressed. This affects the probing of the
kernel modules, which fails if the data are not already cached.
Increment the value of the symtab_type to its compressed variant so the
data could be recovered successfully.
Fixes: ee756ef749 ("perf dso: Add reference count checking and accessor functions")
Signed-off-by: Veronika Molnarova <vmolnaro@redhat.com>
Acked-by: Michael Petlan <mpetlan@redhat.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Michael Petlan <mpetlan@redhat.com>
Link: https://lore.kernel.org/r/20241010144836.16424-1-vmolnaro@redhat.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
If a symbol name is longer than the maximum event length (64 bytes), the
perf tool reports error:
# perf probe -x test_cpp_mangle --add "this_is_a_very_very_long_print_data_abcdefghijklmnopqrstuvwxyz(int)"
snprintf() failed: -7; the event name nbase='this_is_a_very_very_long_print_data_abcdefghijklmnopqrstuvwxyz(int)' is too long
Error: Failed to add events.
An information is missed in the log that the symbol name and the event
name can be set separately. Especially, this is recommended for adding
probe for a long symbol.
This commit refines the log for reminding event syntax.
After:
# perf probe -x test_cpp_mangle --add "this_is_a_very_very_long_print_data_abcdefghijklmnopqrstuvwxyz(int)"
snprintf() failed: -7; the event name 'this_is_a_very_very_long_print_data_abcdefghijklmnopqrstuvwxyz(int)' is too long
Hint: Set a shorter event with syntax "EVENT=PROBEDEF"
EVENT: Event name (max length: 64 bytes).
Error: Failed to add events.
Signed-off-by: Leo Yan <leo.yan@arm.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Link: https://lore.kernel.org/r/20241012204725.928794-4-leo.yan@arm.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Use the info in the metadata to decide if the data source feature is
supported. The CPU MIDR must be in the CPU list for the common data
source encoding.
For the metadata version 1, it doesn't include info for MIDR. In this
case, due to absent info for making decision, print out warning to
remind users to upgrade tool and returns false.
Signed-off-by: Leo Yan <leo.yan@arm.com>
Reviewed-by: James Clark <james.clark@linaro.org>
Link: https://lore.kernel.org/r/20241003185322.192357-5-leo.yan@arm.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
The hashmap__for_each_entry[_safe] is accessing 'map' as if it's a
pointer. But it does without parentheses so passing a static hash map
with an ampersand (like &slab_hash below) caused compiler warnings due
to unmatched types.
In file included from util/bpf_lock_contention.c:5:
util/bpf_lock_contention.c: In function ‘exit_slab_cache_iter’:
linux/tools/perf/util/hashmap.h:169:32: error: invalid type argument of ‘->’ (have ‘struct hashmap’)
169 | for (bkt = 0; bkt < map->cap; bkt++) \
| ^~
util/bpf_lock_contention.c:105:9: note: in expansion of macro ‘hashmap__for_each_entry’
105 | hashmap__for_each_entry(&slab_hash, cur, bkt)
| ^~~~~~~~~~~~~~~~~~~~~~~
/home/namhyung/project/linux/tools/perf/util/hashmap.h:170:31: error: invalid type argument of ‘->’ (have ‘struct hashmap’)
170 | for (cur = map->buckets[bkt]; cur; cur = cur->next)
| ^~
util/bpf_lock_contention.c:105:9: note: in expansion of macro ‘hashmap__for_each_entry’
105 | hashmap__for_each_entry(&slab_hash, cur, bkt)
| ^~~~~~~~~~~~~~~~~~~~~~~
Cc: bpf@vger.kernel.org
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20241009202009.884884-1-namhyung@kernel.org
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
util/tool_pmu.c: In function 'evsel__tool_pmu_read':
util/tool_pmu.c:419:55: error: passing argument 2 of 'tool_pmu__read_event' from incompatible pointer type [-Werror=incompatible-pointer-types]
419 | if (!tool_pmu__read_event(ev, &val)) {
| ^~~~
| |
| long unsigned int *
util/tool_pmu.c:335:56: note: expected 'u64 *' {aka 'long long unsigned int *'} but argument is of type 'long unsigned int *'
335 | bool tool_pmu__read_event(enum tool_pmu_event ev, u64 *result)
| ~~~~~^~~~~~
Link: https://lore.kernel.org/r/Zw1XIGML32VaxE0t@google.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Use the regular PMU approaches with tool json events to reduce the
amount of special tool_pmu code - tool_pmu__config_terms and
tool_pmu__for_each_event_cb are removed. Some functions remain, like
tool_pmu__str_to_event, as conveniences to metricgroups. Add
tool_pmu__skip_event/tool_pmu__num_skip_events to handle the case that
tool json events shouldn't appear on certain architectures. This isn't
done in jevents.py due to complexity in the empty-pmu-events.c and
when all vendor json is built into the tool.
Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20241002032016.333748-10-irogers@google.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Add the expr literals like "#smt_on" as tool events, this allows stat
events to give the values. On my laptop with hyperthreading enabled:
```
$ perf stat -e "has_pmem,num_cores,num_cpus,num_cpus_online,num_dies,num_packages,smt_on,system_tsc_freq" true
Performance counter stats for 'true':
0 has_pmem
8 num_cores
16 num_cpus
16 num_cpus_online
1 num_dies
1 num_packages
1 smt_on
2,496,000,000 system_tsc_freq
0.001113637 seconds time elapsed
0.001218000 seconds user
0.000000000 seconds sys
```
And with hyperthreading disabled:
```
$ perf stat -e "has_pmem,num_cores,num_cpus,num_cpus_online,num_dies,num_packages,smt_on,system_tsc_freq" true
Performance counter stats for 'true':
0 has_pmem
8 num_cores
16 num_cpus
8 num_cpus_online
1 num_dies
1 num_packages
0 smt_on
2,496,000,000 system_tsc_freq
0.000802115 seconds time elapsed
0.000000000 seconds user
0.000806000 seconds sys
```
As zero matters for these values, in stat-display
should_skip_zero_counter only skip the zero value if it is not the
first aggregation index.
The tool event implementations are used in expr but not evaluated as
events for simplicity. Also core_wide isn't made a tool event as it
requires command line parameters.
Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20241002032016.333748-8-irogers@google.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Rather than treat tool events as a special kind of event, create a
tool only PMU where the events/aliases match the existing
duration_time, user_time and system_time events. Remove special
parsing and printing support for the tool events, but add function
calls for when PMU functions are called on a tool_pmu.
Move the tool PMU code in evsel into tool_pmu.c to better encapsulate
the tool event behavior in that file.
Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20241002032016.333748-5-irogers@google.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Hard coded terms like "config=10" are skipped by perf_pmu__config
assuming they were already applied to a perf_event_attr by parse
event's config_attr function. When doing a reverse number to name
lookup in perf_pmu__name_from_config, as the hardcoded terms aren't
applied the config value is incorrect leading to misses or false
matches. Fix this by adding a parameter to have perf_pmu__config apply
hardcoded terms too (not just in parse event's config_term_common).
Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20241002032016.333748-3-irogers@google.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Pull perf tools fixes from Arnaldo Carvalho de Melo:
- Fix an assert() to handle captured and unprocessed ARM CoreSight CPU
traces
- Fix static build compilation error when libdw isn't installed or is
too old
- Add missing include when building with
!HAVE_DWARF_GETLOCATIONS_SUPPORT
- Add missing refcount put on 32-bit DSOs
- Fix disassembly of user space binaries by setting the binary_type of
DSO when loading
- Update headers with the kernel sources, including asound.h, sched.h,
fcntl, msr-index.h, irq_vectors.h, socket.h, list_sort.c and arm64's
cputype.h
* tag 'perf-tools-fixes-for-v6.12-1-2024-10-08' of git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools:
perf cs-etm: Fix the assert() to handle captured and unprocessed cpu trace
perf build: Fix build feature-dwarf_getlocations fail for old libdw
perf build: Fix static compilation error when libdw is not installed
perf dwarf-aux: Fix build with !HAVE_DWARF_GETLOCATIONS_SUPPORT
tools headers arm64: Sync arm64's cputype.h with the kernel sources
perf tools: Cope with differences for lib/list_sort.c copy from the kernel
tools check_headers.sh: Add check variant that excludes some hunks
perf beauty: Update copy of linux/socket.h with the kernel sources
tools headers UAPI: Sync the linux/in.h with the kernel sources
perf trace beauty: Update the arch/x86/include/asm/irq_vectors.h copy with the kernel sources
tools arch x86: Sync the msr-index.h copy with the kernel sources
tools include UAPI: Sync linux/fcntl.h copy with the kernel sources
tools include UAPI: Sync linux/sched.h copy with the kernel sources
tools include UAPI: Sync sound/asound.h copy with the kernel sources
perf vdso: Missed put on 32-bit dsos
perf symbol: Set binary_type of dso when loading
This commit dumps metadata with version 2. It dumps metadata for header
and per CPU data respectively in the arm_spe_print_info() function to
support metadata version 2 format.
After:
0 0 0x3c0 [0x1b0]: PERF_RECORD_AUXTRACE_INFO type: 4
Header version :2
Header size :4
PMU type v2 :13
CPU number :8
Magic :0x1010101010101010
CPU # :0
Num of params :3
MIDR :0x410fd801
PMU Type :-1
Min Interval :0
Magic :0x1010101010101010
CPU # :1
Num of params :3
MIDR :0x410fd801
PMU Type :-1
Min Interval :0
Magic :0x1010101010101010
CPU # :2
Num of params :3
MIDR :0x410fd870
PMU Type :13
Min Interval :1024
Magic :0x1010101010101010
CPU # :3
Num of params :3
MIDR :0x410fd870
PMU Type :13
Min Interval :1024
Magic :0x1010101010101010
CPU # :4
Num of params :3
MIDR :0x410fd870
PMU Type :13
Min Interval :1024
Magic :0x1010101010101010
CPU # :5
Num of params :3
MIDR :0x410fd870
PMU Type :13
Min Interval :1024
Magic :0x1010101010101010
CPU # :6
Num of params :3
MIDR :0x410fd850
PMU Type :-1
Min Interval :0
Magic :0x1010101010101010
CPU # :7
Num of params :3
MIDR :0x410fd850
PMU Type :-1
Min Interval :0
Signed-off-by: Leo Yan <leo.yan@arm.com>
Reviewed-by: James Clark <james.clark@linaro.org>
Cc: Will Deacon <will@kernel.org>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Besar Wicaksono <bwicaksono@nvidia.com>
Cc: John Garry <john.g.garry@oracle.com>
Link: https://lore.kernel.org/r/20241003184302.190806-6-leo.yan@arm.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
The "perf record" tool will now default to this new mode if the user
specifies a sampling group when not in system-wide mode, and when
"--no-inherit" is not specified.
This change updates evsel to allow the combination of inherit
and PERF_SAMPLE_READ.
A fallback is implemented for kernel versions where this feature is not
supported.
Signed-off-by: Ben Gainey <ben.gainey@arm.com>
Cc: james.clark@arm.com
Link: https://lore.kernel.org/r/20241001121505.1009685-3-ben.gainey@arm.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Sample period calculation in deliver_sample_value is updated to
calculate the per-thread period delta for events that are inherit +
PERF_SAMPLE_READ. When the sampling event has this configuration, the
read_format.id is used with the tid from the sample to lookup the
storage of the previously accumulated counter total before calculating
the delta. All existing valid configurations where read_format.value
represents some global value continue to use just the read_format.id to
locate the storage of the previously accumulated total.
perf_sample_id is modified to support tracking per-thread
values, along with the existing global per-id values. In the
per-thread case, values are stored in a hash by tid within the
perf_sample_id, and are dynamically allocated as the number is not known
ahead of time.
Signed-off-by: Ben Gainey <ben.gainey@arm.com>
Cc: james.clark@arm.com
Link: https://lore.kernel.org/r/20241001121505.1009685-2-ben.gainey@arm.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
asm/unaligned.h is always an include of asm-generic/unaligned.h;
might as well move that thing to linux/unaligned.h and include
that - there's nothing arch-specific in that header.
auto-generated by the following:
for i in `git grep -l -w asm/unaligned.h`; do
sed -i -e "s/asm\/unaligned.h/linux\/unaligned.h/" $i
done
for i in `git grep -l -w asm-generic/unaligned.h`; do
sed -i -e "s/asm-generic\/unaligned.h/linux\/unaligned.h/" $i
done
git mv include/asm-generic/unaligned.h include/linux/unaligned.h
git mv tools/include/asm-generic/unaligned.h tools/include/linux/unaligned.h
sed -i -e "/unaligned.h/d" include/asm-generic/Kbuild
sed -i -e "s/__ASM_GENERIC/__LINUX/" include/linux/unaligned.h tools/include/linux/unaligned.h