Utilizes the previous is_breg_access_indirect function to determine if
the register + offset stores the variable itself or the struct it points
to, save the information in die_var_type.is_reg_var_addr.
Since we are storing the real types in the stack state, we need to do a
type dereference when is_reg_var_addr is set to false for stack/frame
registers.
For other gp registers, skip the variable when the register is a pointer
to the type. If we want to accept these variables, we might also utilize
is_reg_var_addr in a different way, we need to mark that register as a
pointer to the type.
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Zecheng Li <zecheng@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.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: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Xu Liu <xliuprof@google.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Introduces the function is_breg_access_indirect to determine whether a
memory access involving a DW_OP_breg* operation refers to the variable's
value directly or requires dereferencing the variable's type as a
pointer based on the DWARF expression.
Previously, all breg based accesses were assumed to directly access the
variable's value (is_pointer = false).
The is_breg_access_indirect function handles three cases:
1. Base register + offset only: (e.g., DW_OP_breg7 RSP+88) The
calculated address is the location of the variable. The access is
direct, so no type dereference is needed. Returns false.
2. Base register + offset, followed by other operations ending in
DW_OP_stack_value, including DW_OP_deref: (e.g., DW_OP_breg*,
DW_OP_deref, DW_OP_stack_value) The DWARF expression computes the
variable's value, but that value requires a dereference. The memory
access is fetching that value, so no type dereference is needed.
Returns false.
3. Base register + offset, followed only by DW_OP_stack_value: (e.g.,
DW_OP_breg13 R13+256, DW_OP_stack_value) This indicates the value at
the base + offset is the variable's value. Since this value is being
used as an address in the memory access, the variable's type is
treated as a pointer and requires a type dereference. Returns true.
The is_pointer argument passed to match_var_offset is now set by
is_breg_access_indirect for breg accesses.
There are more complex expressions that includes multiple operations and
may require additional handling, such as DW_OP_deref without a
DW_OP_stack_value, or including multiple base registers. They are less
common in the Linux kernel dwarf and are skipped in check_allowed_ops.
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Zecheng Li <zecheng@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.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: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Xu Liu <xliuprof@google.com>
Link: https://lore.kernel.org/r/CAJUgMyK2wTiEZB__dtgCELmaNGFWhG1j0g9rv_C=cLD6Zq4_5w@mail.gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Current code skips to parse events after generating data source. The
reason is the data source packets have cache and snooping related info,
the afterwards event packets might contain duplicate info.
This commit changes to continue parsing the events after data source
analysis. If data source does not give out memory level and snooping
types, then the event info is used to synthesize the related fields.
As a result, both the peer snoop option ('-d peer') and hitm options
('-d tot/lcl/rmt') are supported by Arm SPE in 'perf c2c'.
Reviewed-by: James Clark <james.clark@linaro.org>
Signed-off-by: Leo Yan <leo.yan@arm.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ali Saidi <alisaidi@amazon.com>
Cc: German Gomez <german.gomez@arm.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Since FEAT_SPEv1p4, Arm SPE provides two extra events: "Cache data
modified" and "Data snooped".
Set the snoop mode as:
- If both the "Cache data modified" event and the "Data snooped" event
are set, which indicates a load operation that snooped from a outside
cache and hit a modified copy, set the HITM flag to inspect false
sharing.
- If the snooped event bit is not set, and the snooped event has been
supported by the hardware, set as NONE mode (no snoop operation).
- If the snooped event bit is not set, and the event is not supported or
absent the events info in the meta data, set as NA mode (not
available).
Don't set any mode for only "Cache data modified" event, as it hits a
local modified copy.
Reviewed-by: James Clark <james.clark@linaro.org>
Signed-off-by: Leo Yan <leo.yan@arm.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ali Saidi <alisaidi@amazon.com>
Cc: German Gomez <german.gomez@arm.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
__maps__fixup_overlap_and_insert may split or directly insert a map,
when doing this the map may need to have a kmap set up for the sake of
the kmaps. The missing kmap set up fails the check_invariants test in
maps, later "Internal error" reports from map__kmap and ultimately
causes segfaults.
Similar fixes were added in commit e0e4e0b8b7 ("perf maps: Add
missing map__set_kmap_maps() when replacing a kernel map") and commit
25d9c0301d ("perf maps: Set the kmaps for newly created/added kernel
maps") but they missed cases. To try to reduce the risk of this,
update the kmap directly following any manual insert. This identified
another problem in maps__copy_from.
Fixes: e0e4e0b8b7 ("perf maps: Add missing map__set_kmap_maps() when replacing a kernel map")
Fixes: 25d9c0301d ("perf maps: Set the kmaps for newly created/added kernel maps")
Signed-off-by: Ian Rogers <irogers@google.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
The function parse_events__sort_events_and_fix_groups is needed to fix
uncore events like:
```
$ perf stat -e '{data_read,data_write}' ...
```
so that the multiple uncore PMUs have a group each of data_read and
data_write events.
The same function will perform architecture sorting and group fixing,
in particular for Intel topdown/perf-metric events. Grouping multiple
perf metric events together causes perf_event_open to fail as the
group can only support one. This means command lines like:
```
$ perf stat -e 'slots,slots' ...
```
fail as the slots events are forced into a group together to try to
satisfy the perf-metric event constraints.
As the user may know better than
parse_events__sort_events_and_fix_groups add a 'X' modifier to skip
its regrouping behavior. This allows the following to succeed rather
than fail on the second slots event being opened:
```
$ perf stat -e 'slots,slots:X' -a sleep 1
Performance counter stats for 'system wide':
6,834,154,071 cpu_core/slots/ (50.13%)
5,548,629,453 cpu_core/slots/X (49.87%)
1.002634606 seconds time elapsed
```
Closes: https://lore.kernel.org/lkml/20250822082233.1850417-1-dapeng1.mi@linux.intel.com/
Reported-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
Reported-by: Xudong Hao <xudong.hao@intel.com>
Reviewed-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
Signed-off-by: Ian Rogers <irogers@google.com>
Tested-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Howard Chu <howardchu95@gmail.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: Thomas Falcon <thomas.falcon@intel.com>
Cc: Yoshihiro Furudera <fj5100bi@fujitsu.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The lzma_is_compressed and gzip_is_compressed functions are declared
to return a "bool" type, but in case of an error (e.g., file open
failure), they incorrectly returned -1.
A bool type is a boolean value that is either true or false.
Returning -1 for a bool return type can lead to unexpected behavior
and may violate strict type-checking in some compilers.
Fix the return value to be false in error cases, ensuring the function
adheres to its declared return type improves for preventing potential
bugs related to type mismatch.
Fixes: 4b57fd44b6 ("perf tools: Add lzma_is_compressed function")
Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: Yunseong Kim <ysk@kzalloc.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephen Brennan <stephen.s.brennan@oracle.com>
Link: https://lore.kernel.org/r/20250822162506.316844-3-ysk@kzalloc.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The various sample types that are generated are based on the same SPE
sample, just placed into different sample type bins.
The same sample can be in multiple bins if it has flags set that cause
it to be.
Currently we're only applying the --itrace interval downsampling to the
instruction bin, which means that the sample would appear in one bin but
not another if it was skipped due to downsampling.
I don't thing anyone would want or expect this, so make this behave
consistently by applying the downsampling before generating any sample.
You might argue that the "instructions" interval type doesn't make sense
to apply to "memory" sample types because it would be skipping every n
memory samples, rather than every n instructions.
ut the downsampling was already not an instruction interval even for the
instruction samples. SPE has a hardware based sampling interval, and the
instruction interval was just a convenient way to specify further
downsampling.
This is hinted at in the warning message shown for intervals greater
than 1.
This makes SPE diverge from trace technologies like Intel PT and Arm
Coresight.
In those cases instruction samples can be reduced but all branches are
still emitted. This makes sense there, because branches form a complete
execution history, and asking to skip branches every n instructions
doesn't really make sense.
But for SPE, as mentioned above, downsampling the instruction samples
already wasn't consistent with trace technologies so we ended up with
some middle ground that had no benefit.
Now it's possible to reduce the volume of samples in all groups and
samples won't be missing from one group but present in another.
Reviewed-by: Leo Yan <leo.yan@arm.com>
Signed-off-by: James Clark <james.clark@linaro.org>
Tested-by: Leo Yan <leo.yan@arm.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ben Gainey <Ben.Gainey@arm.com>
Cc: George Wort <George.Wort@arm.com>
Cc: Graham Woodward <Graham.Woodward@arm.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: John Garry <john.g.garry@oracle.com>
Cc: Leo Yan <leo.yan@linux.dev>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Michael Williams <Michael.Williams@arm.com>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
I started seeing this in recent Fedora 42 kernels:
# uname -a
Linux number 6.16.3-200.fc42.x86_64 #1 SMP PREEMPT_DYNAMIC Sat Aug 23 17:02:17 UTC 2025 x86_64 GNU/Linux
#
# perf test vmlinux
1: vmlinux symtab matches kallsyms : FAILED!
#
Rust is enabled and these were the symbols causing the above failure,
i.e. found in vmlinux but not in /proc/kallsyms:
$ grep -w N /proc/kallsyms
0000000000000000 N __pfx__RNCINvNtNtNtCsbDUBuN8AbD4_4core4iter8adapters3map12map_try_foldjNtCs6vVzKs5jPr6_12drm_panic_qr7VersionuINtNtNtBa_3ops12control_flow11ControlFlowB10_ENcB10_0NCINvNvNtNtNtB8_6traits8iterator8Iterator4find5checkB10_NCNvMB12_B10_13from_segments0E0E0B12_
0000000000000000 N _RNCINvNtNtNtCsbDUBuN8AbD4_4core4iter8adapters3map12map_try_foldjNtCs6vVzKs5jPr6_12drm_panic_qr7VersionuINtNtNtBa_3ops12control_flow11ControlFlowB10_ENcB10_0NCINvNvNtNtNtB8_6traits8iterator8Iterator4find5checkB10_NCNvMB12_B10_13from_segments0E0E0B12_
$
So accept those 'N' symbols as well.
About them, from 'man nm':
"N" The symbol is a debugging symbol.
"n" The symbol is in a non-data, non-code, non-debug read-only section.
Reviewed-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Miguel Ojeda <ojeda@kernel.org>
Cc: James Clark <james.clark@linaro.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To pick the fixes sent by Namhyung for tools/perf for v6.17-rc5 and get
closer to the other tools code that is used by tools/perf.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add a compute_metric function that computes a metric double value for a
given evlist, metric name, CPU and thread. For example:
```
>>> import perf
>>> x = perf.parse_metrics("TopdownL1")
>>> x.open()
>>> x.enable()
>>> x.disable()
>>> x.metrics()
['tma_bad_speculation', 'tma_frontend_bound', 'tma_backend_bound', 'tma_retiring']
>>> x.compute_metric('tma_bad_speculation', 0, -1)
0.08605342847131037
```
Committer notes:
Initialize thread_idx and cpu_idx to zero as albeit them not possibly
coming out unitialized from the loop as mexp would be not NULL only if
they were initialized, some older compilers don't notice that and error
with:
GEN /tmp/build/perf/python/perf.cpython-36m-x86_64-linux-gnu.so
/git/perf-6.17.0-rc3/tools/perf/util/python.c: In function ‘pyrf_evlist__compute_metric’:
/git/perf-6.17.0-rc3/tools/perf/util/python.c:1363:3: error: ‘thread_idx’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
evsel__read_counter(metric_events[i], cpu_idx, thread_idx);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/git/perf-6.17.0-rc3/tools/perf/util/python.c:1389:41: note: ‘thread_idx’ was declared here
int ret, cpu = 0, cpu_idx, thread = 0, thread_idx;
^~~~~~~~~~
/git/perf-6.17.0-rc3/tools/perf/util/python.c:1363:3: error: ‘cpu_idx’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
evsel__read_counter(metric_events[i], cpu_idx, thread_idx);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/git/perf-6.17.0-rc3/tools/perf/util/python.c:1389:20: note: ‘cpu_idx’ was declared here
int ret, cpu = 0, cpu_idx, thread = 0, thread_idx;
^~~~~~~
/git/perf-6.17.0-rc3/tools/perf/util/python.c: At top level:
cc1: error: unrecognized command line option ‘-Wno-cast-function-type’ [-Werror]
cc1: all warnings being treated as errors
error: command 'gcc' failed with exit status 1
cp: cannot stat '/tmp/build/perf/python_ext_build/lib/perf*.so': No such file or directory
Reviewed-by: Howard Chu <howardchu95@gmail.com>
Signed-off-by: Ian Rogers <irogers@google.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Chun-Tse Shao <ctshao@google.com>
Cc: Collin Funk <collin.funk1@gmail.com>
Cc: Dr. David Alan Gilbert <linux@treblig.org>
Cc: Gautam Menghani <gautam@linux.ibm.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: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Falcon <thomas.falcon@intel.com>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Cc: Tiezhu Yang <yangtiezhu@loongson.cn>
Cc: Weilin Wang <weilin.wang@intel.com>
Cc: Xu Yang <xu.yang_2@nxp.com>
Link: https://lore.kernel.org/r/20250819013941.209033-9-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
In get_bpf_prog_info_linear two calls to bpf_obj_get_info_by_fd are
made, the first to compute memory requirements for a struct perf_bpil
and the second to fill it in. Previously the code would warn when the
second call didn't match the first. Such races can be common place in
things like perf test, whose perf trace tests will frequently load BPF
programs. Rather than a debug message, return actual errors for this
case. Out of paranoia also validate the read bpf_prog_info array
value. Change the type of ptr to avoid mismatched pointer type
compiler warnings. Add some additional debug print outs and sanity
asserts.
Closes: https://lore.kernel.org/lkml/CAP-5=fWJQcmUOP7MuCA2ihKnDAHUCOBLkQFEkQES-1ZZTrgf8Q@mail.gmail.com/
Fixes: 6ac22d036f ("perf bpf: Pull in bpf_program__get_prog_info_linear()")
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Ian Rogers <irogers@google.com>
Link: https://lore.kernel.org/r/20250902181713.309797-4-irogers@google.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Calls to perf_env__insert_bpf_prog_info may fail as a sideband thread
may already have inserted the bpf_prog_info. Such failures may yield
info_linear being freed which then causes use-after-free issues with
the internal bpf_prog_info info struct. Make it so that
perf_env__insert_bpf_prog_info trigger early non-error paths and fix
the use-after-free in perf_event__synthesize_one_bpf_prog. Add proper
return error handling to perf_env__add_bpf_info (that calls
perf_env__insert_bpf_prog_info) and propagate the return value in its
callers.
Closes: https://lore.kernel.org/lkml/CAP-5=fWJQcmUOP7MuCA2ihKnDAHUCOBLkQFEkQES-1ZZTrgf8Q@mail.gmail.com/
Fixes: 03edb7020b ("perf bpf: Fix two memory leakages when calling perf_env__insert_bpf_prog_info()")
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Ian Rogers <irogers@google.com>
Link: https://lore.kernel.org/r/20250902181713.309797-2-irogers@google.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
