Since get_states() assumes the existence of libtraceevent, so move
to where it should belong, i.e, util/trace-event-parse.c, and also
rename it to parse_task_states().
Leave evsel_getstate() untouched as it fits well in the evsel
category.
Also make some necessary tweaks for python support, and get it
verified with: perf test python.
Signed-off-by: Ze Gao <zegao@tencent.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20240123070210.1669843-2-zegao@tencent.com
The 'Session topology' test currently fails with this message when
evlist__new_default() opens more than one event:
32: Session topology :
--- start ---
templ file: /tmp/perf-test-vv5YzZ
Using CPUID 0x00000000410fd070
Opening: unknown-hardware:HG
------------------------------------------------------------
perf_event_attr:
type 0 (PERF_TYPE_HARDWARE)
config 0xb00000000
disabled 1
------------------------------------------------------------
sys_perf_event_open: pid 0 cpu -1 group_fd -1 flags 0x8 = 4
Opening: unknown-hardware:HG
------------------------------------------------------------
perf_event_attr:
type 0 (PERF_TYPE_HARDWARE)
config 0xa00000000
disabled 1
------------------------------------------------------------
sys_perf_event_open: pid 0 cpu -1 group_fd -1 flags 0x8 = 5
non matching sample_type
FAILED tests/topology.c:73 can't get session
---- end ----
Session topology: FAILED!
This is because when re-opening the file and parsing the header, Perf
expects that any file that has more than one event has the sample ID
flag set. Perf record already sets the flag in a similar way when there
is more than one event, so add the same logic to evlist__new_default().
evlist__new_default() is only currently used in tests, so I don't
expect this change to have any other side effects. The other tests that
use it don't save and re-open the file so don't hit this issue.
The session topology test has been failing on Arm big.LITTLE platforms
since commit 251aa04024 ("perf parse-events: Wildcard most
"numeric" events") when evlist__new_default() started opening multiple
events for 'cycles'.
Fixes: 251aa04024 ("perf parse-events: Wildcard most "numeric" events")
Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: James Clark <james.clark@arm.com>
[ This was failing as well on a Rocket Lake Refresh/14700k Intel hybrid system - Arnaldo ]
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Tested-by: Ian Rogers <irogers@google.com>
Tested-by: Kan Liang <kan.liang@linux.intel.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Changbin Du <changbin.du@huawei.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Yang Jihong <yangjihong1@huawei.com>
Closes: https://lore.kernel.org/lkml/CAP-5=fWVQ-7ijjK3-w1q+k2WYVNHbAcejb-xY0ptbjRw476VKA@mail.gmail.com/
Link: https://lore.kernel.org/r/20240124094358.489372-1-james.clark@arm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The msr PMU is a software one, meaning msr events may be grouped
with events in a hardware context. As the msr PMU isn't marked as a
software PMU by perf_pmu__is_software, groups with the msr PMU in
are broken and the msr events placed in a different group. This
may lead to multiplexing errors where a hardware event isn't
counted while the msr event, such as tsc, is. Fix all of this by
marking the msr PMU as software, which agrees with the driver.
Before:
```
$ perf stat -e '{slots,tsc}' -a true
WARNING: events were regrouped to match PMUs
Performance counter stats for 'system wide':
1,750,335 slots
4,243,557 tsc
0.001456717 seconds time elapsed
```
After:
```
$ perf stat -e '{slots,tsc}' -a true
Performance counter stats for 'system wide':
12,526,380 slots
3,415,163 tsc
0.001488360 seconds time elapsed
```
Fixes: 251aa04024 ("perf parse-events: Wildcard most "numeric" events")
Signed-off-by: Ian Rogers <irogers@google.com>
Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
Cc: James Clark <james.clark@arm.com>
Cc: Caleb Biggers <caleb.biggers@intel.com>
Cc: Edward Baker <edward.baker@intel.com>
Cc: Perry Taylor <perry.taylor@intel.com>
Cc: Samantha Alt <samantha.alt@intel.com>
Cc: Weilin Wang <weilin.wang@intel.com>
Link: https://lore.kernel.org/r/20240124234200.1510417-1-irogers@google.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
The 'Session topology' test currently fails with this message when
evlist__new_default() opens more than one event:
32: Session topology :
--- start ---
templ file: /tmp/perf-test-vv5YzZ
Using CPUID 0x00000000410fd070
Opening: unknown-hardware:HG
------------------------------------------------------------
perf_event_attr:
type 0 (PERF_TYPE_HARDWARE)
config 0xb00000000
disabled 1
------------------------------------------------------------
sys_perf_event_open: pid 0 cpu -1 group_fd -1 flags 0x8 = 4
Opening: unknown-hardware:HG
------------------------------------------------------------
perf_event_attr:
type 0 (PERF_TYPE_HARDWARE)
config 0xa00000000
disabled 1
------------------------------------------------------------
sys_perf_event_open: pid 0 cpu -1 group_fd -1 flags 0x8 = 5
non matching sample_type
FAILED tests/topology.c:73 can't get session
---- end ----
Session topology: FAILED!
This is because when re-opening the file and parsing the header, Perf
expects that any file that has more than one event has the sample ID
flag set. Perf record already sets the flag in a similar way when there
is more than one event, so add the same logic to evlist__new_default().
evlist__new_default() is only currently used in tests, so I don't
expect this change to have any other side effects. The other tests that
use it don't save and re-open the file so don't hit this issue.
The session topology test has been failing on Arm big.LITTLE platforms
since commit 251aa04024 ("perf parse-events: Wildcard most
"numeric" events") when evlist__new_default() started opening multiple
events for 'cycles'.
Fixes: 251aa04024 ("perf parse-events: Wildcard most "numeric" events")
Closes: https://lore.kernel.org/lkml/CAP-5=fWVQ-7ijjK3-w1q+k2WYVNHbAcejb-xY0ptbjRw476VKA@mail.gmail.com/
Tested-by: Ian Rogers <irogers@google.com>
Reviewed-by: Ian Rogers <irogers@google.com>
Tested-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: James Clark <james.clark@arm.com>
Cc: Changbin Du <changbin.du@huawei.com>
Cc: Yang Jihong <yangjihong1@huawei.com>
Link: https://lore.kernel.org/r/20240124094358.489372-1-james.clark@arm.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Perf uses a hard coded string "RSDTtXZPI" to index the sched_switch
prev_state field raw bitmask value. This works well except for when
the kernel changes this string, in which case this will break again.
Instead we add a new way to parse task state string from tracepoint
print format already recorded by perf, which eliminates the further
dependencies with this hardcode and unmaintainable macro, and this
is exactly what libtraceevent[1] does for now.
So we borrow the print flags parsing logic from libtraceevent[1].
And in get_states(), we walk the print arguments until the
__print_flags() for the target state field is found, and use that to
build the states string for future parsing.
[1]: https://lore.kernel.org/linux-trace-devel/20231224140732.7d41698d@rorschach.local.home/
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Ze Gao <zegao@tencent.com>
Link: https://lore.kernel.org/r/20240122070859.1394479-4-zegao@tencent.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
In pipe mode, no need to switch perf data output, therefore,
'--timestamp-filename' option should not take effect.
Check the conflict before recording and output WARNING.
In this case, the check pipe mode in perf_data__switch() can be removed.
Before:
# perf record --timestamp-filename -o- perf test -w noploop | perf report -i- --percent-limit=1
# To display the perf.data header info, please use --header/--header-only options.
#
[ perf record: Woken up 1 times to write data ]
[ perf record: Dump -.2024011812110182 ]
#
# Total Lost Samples: 0
#
# Samples: 4K of event 'cycles:P'
# Event count (approx.): 2176784359
#
# Overhead Command Shared Object Symbol
# ........ ....... .................... ......................................
#
97.83% perf perf [.] noploop
#
# (Tip: Print event counts in CSV format with: perf stat -x,)
#
After:
# perf record --timestamp-filename -o- perf test -w noploop | perf report -i- --percent-limit=1
WARNING: --timestamp-filename option is not available in pipe mode.
# To display the perf.data header info, please use --header/--header-only options.
#
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.000 MB - ]
#
# Total Lost Samples: 0
#
# Samples: 4K of event 'cycles:P'
# Event count (approx.): 2185575421
#
# Overhead Command Shared Object Symbol
# ........ ....... ..................... .............................................
#
97.75% perf perf [.] noploop
#
# (Tip: Profiling branch (mis)predictions with: perf record -b / perf report)
#
Fixes: ecfd7a9c04 ("perf record: Add '--timestamp-filename' option to append timestamp to output file name")
Signed-off-by: Yang Jihong <yangjihong1@huawei.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20240119040304.3708522-3-yangjihong1@huawei.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
The DWARF location expression can be fairly complex and it'd be hard
to match it with the condition correctly. So let's be conservative
and only allow simple expressions. For now it just checks the first
operation in the list. The following operations looks ok:
* DW_OP_stack_value
* DW_OP_deref_size
* DW_OP_deref
* DW_OP_piece
To refuse complex (and unsupported) location expressions, add
check_allowed_ops() to compare the rest of the list. It seems earlier
result contained those unsupported expressions. For example, I found
some local struct variable is placed like below.
<2><43d1517>: Abbrev Number: 62 (DW_TAG_variable)
<43d1518> DW_AT_location : 15 byte block: 91 50 93 8 91 78 93 4 93 84 8 91 68 93 4
(DW_OP_fbreg: -48; DW_OP_piece: 8;
DW_OP_fbreg: -8; DW_OP_piece: 4;
DW_OP_piece: 1028;
DW_OP_fbreg: -24; DW_OP_piece: 4)
Another example is something like this.
0057c8be ffffffffffffffff ffffffff812109f0 (base address)
0057c8ce ffffffff812112b5 ffffffff812112c8 (DW_OP_breg3 (rbx): 0;
DW_OP_constu: 18446744073709551612;
DW_OP_and;
DW_OP_stack_value)
It should refuse them. After the change, the stat shows:
Annotate data type stats:
total 294, ok 158 (53.7%), bad 136 (46.3%)
-----------------------------------------------------------
30 : no_sym
32 : no_mem_ops
53 : no_var
14 : no_typeinfo
7 : bad_offset
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Reviewed-by: Ian Rogers <irogers@google.com>
Cc: Stephane Eranian <eranian@google.com>
Link: https://lore.kernel.org/r/20240117062657.985479-10-namhyung@kernel.org
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Local variables are allocated in the stack and the location list
should look like base register(s) and an offset. Extend the
die_find_variable_by_reg() to handle the following expressions
* DW_OP_breg{0..31}
* DW_OP_bregx
* DW_OP_fbreg
Ususally DWARF subprogram entries have frame base information and
use it to locate stack variable like below:
<2><43d1575>: Abbrev Number: 62 (DW_TAG_variable)
<43d1576> DW_AT_location : 2 byte block: 91 7c (DW_OP_fbreg: -4) <--- here
<43d1579> DW_AT_name : (indirect string, offset: 0x2c00c9): i
<43d157d> DW_AT_decl_file : 1
<43d157e> DW_AT_decl_line : 78
<43d157f> DW_AT_type : <0x43d19d7>
I found some differences on saving the frame base between gcc and clang.
The gcc uses the CFA to get the base so it needs to check the current
frame's CFI info. In this case, stack offset needs to be adjusted from
the start of the CFA.
<1><1bb8d>: Abbrev Number: 102 (DW_TAG_subprogram)
<1bb8e> DW_AT_name : (indirect string, offset: 0x74d41): kernel_init
<1bb92> DW_AT_decl_file : 2
<1bb92> DW_AT_decl_line : 1440
<1bb94> DW_AT_decl_column : 18
<1bb95> DW_AT_prototyped : 1
<1bb95> DW_AT_type : <0xcc>
<1bb99> DW_AT_low_pc : 0xffffffff81bab9e0
<1bba1> DW_AT_high_pc : 0x1b2
<1bba9> DW_AT_frame_base : 1 byte block: 9c (DW_OP_call_frame_cfa) <------ here
<1bbab> DW_AT_call_all_calls: 1
<1bbab> DW_AT_sibling : <0x1bf5a>
While clang sets it to a register directly and it can check the register
and offset in the instruction directly.
<1><43d1542>: Abbrev Number: 60 (DW_TAG_subprogram)
<43d1543> DW_AT_low_pc : 0xffffffff816a7c60
<43d154b> DW_AT_high_pc : 0x98
<43d154f> DW_AT_frame_base : 1 byte block: 56 (DW_OP_reg6 (rbp)) <---------- here
<43d1551> DW_AT_GNU_all_call_sites: 1
<43d1551> DW_AT_name : (indirect string, offset: 0x3bce91): foo
<43d1555> DW_AT_decl_file : 1
<43d1556> DW_AT_decl_line : 75
<43d1557> DW_AT_prototyped : 1
<43d1557> DW_AT_type : <0x43c7332>
<43d155b> DW_AT_external : 1
Also it needs to update the offset after finding the type like global
variables since the offset was from the frame base. Factor out
match_var_offset() to check global and local variables in the same way.
The type stats are improved too:
Annotate data type stats:
total 294, ok 160 (54.4%), bad 134 (45.6%)
-----------------------------------------------------------
30 : no_sym
32 : no_mem_ops
51 : no_var
14 : no_typeinfo
7 : bad_offset
Reviewed-by: Ian Rogers <irogers@google.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Link: https://lore.kernel.org/r/20240117062657.985479-9-namhyung@kernel.org
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Global variables are accessed using PC-relative address so it needs to
be handled separately. The PC-rel addressing is detected by using
DWARF_REG_PC. On x86, %rip register would be used.
The address can be calculated using the ip and offset in the
instruction. But it should start from the next instruction so add
calculate_pcrel_addr() to do it properly.
But global variables defined in a different file would only have a
declaration which doesn't include a location list. So it first tries
to get the type info using the address, and then looks up the variable
declarations using name. The name of global variables should be get
from the symbol table. The declaration would have the type info.
So extend find_var_type() to take both address and name for global
variables.
The stat is now looks like:
Annotate data type stats:
total 294, ok 153 (52.0%), bad 141 (48.0%)
-----------------------------------------------------------
30 : no_sym
32 : no_mem_ops
61 : no_var
10 : no_typeinfo
8 : bad_offset
Reviewed-by: Ian Rogers <irogers@google.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Link: https://lore.kernel.org/r/20240117062657.985479-7-namhyung@kernel.org
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Extend find_data_type_die() to find data type from PC-relative address
using die_find_variable_by_addr(). Users need to pass the address for
the (global) variable.
The offset for the variable should be updated after finding the type
because the offset in the instruction is just to calcuate the address
for the variable. So it changed to pass a pointer to offset and renamed
it to 'poffset'.
First it searches variables in the CU DIE as it's likely that the global
variables are defined in the file level. And then it iterates the scope
DIEs to find a local (static) variable.
Reviewed-by: Ian Rogers <irogers@google.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Link: https://lore.kernel.org/r/20240117062657.985479-6-namhyung@kernel.org
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
A typical function prologue and epilogue include multiple stack
operations to save and restore the current value of registers.
On x86, it looks like below:
push r15
push r14
push r13
push r12
...
pop r12
pop r13
pop r14
pop r15
ret
As these all touches the stack memory region, chances are high that they
appear in a memory profile data. But these are not used for any real
purpose yet so it'd return no types.
One of my profile type shows that non neglible portion of data came from
the stack operations. It also seems GCC generates more stack operations
than clang.
Annotate Instruction stats
total 264, ok 169 (64.0%), bad 95 (36.0%)
Name : Good Bad
-----------------------------------------------------------
movq : 49 27
movl : 24 9
popq : 0 19 <-- here
cmpl : 17 2
addq : 14 1
cmpq : 12 2
cmpxchgl : 3 7
Instead of dealing them as unknown, let's create a seperate pseudo type
to represent those stack operations separately.
Reviewed-by: Ian Rogers <irogers@google.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Link: https://lore.kernel.org/r/20240117062657.985479-5-namhyung@kernel.org
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
On x86, instructions for array access often looks like below.
mov 0x1234(%rax,%rbx,8), %rcx
Usually the first register holds the type information and the second one
has the index. And the current code only looks up a variable for the
first register. But it's possible to be in the other way around so it
needs to check the second register if the first one failed.
The stat changed like this.
Annotate data type stats:
total 294, ok 148 (50.3%), bad 146 (49.7%)
-----------------------------------------------------------
30 : no_sym
32 : no_mem_ops
66 : no_var
10 : no_typeinfo
8 : bad_offset
Reviewed-by: Ian Rogers <irogers@google.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Link: https://lore.kernel.org/r/20240117062657.985479-4-namhyung@kernel.org
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
When a sample was come from a conditional branch without a memory
operand, it could be due to a macro fusion with a previous instruction.
So it needs to check the memory operand in the previous one.
This improves the stat like below:
Annotate data type stats:
total 294, ok 147 (50.0%), bad 147 (50.0%)
-----------------------------------------------------------
30 : no_sym
32 : no_mem_ops
71 : no_var
6 : no_typeinfo
8 : bad_offset
Reviewed-by: Ian Rogers <irogers@google.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Link: https://lore.kernel.org/r/20240117062657.985479-3-namhyung@kernel.org
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
For the performance reason, I prefer llvm-objdump over GNU's. But I
found that llvm-objdump puts x86 lock prefix in a separate line like
below.
ffffffff81000695: f0 lock
ffffffff81000696: ff 83 54 0b 00 00 incl 2900(%rbx)
This should be parsed properly, but I just changed to find the insn
with next offset for now.
This improves the statistics as it can process more instructions.
Annotate data type stats:
total 294, ok 144 (49.0%), bad 150 (51.0%)
-----------------------------------------------------------
30 : no_sym
35 : no_mem_ops
71 : no_var
6 : no_typeinfo
8 : bad_offset
Reviewed-by: Ian Rogers <irogers@google.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Link: https://lore.kernel.org/r/20240117062657.985479-2-namhyung@kernel.org
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
The addr_location map and maps fields in the inner loop were missing
calls to map__get()/maps__get(). The subsequent addr_location__exit()
call in each loop puts the map/maps fields causing use-after-free
aborts.
This issue reproduces on at least arm64 and x86_64 with something
simple like `perf record -g ls` followed by `perf script -s script.py`
with the following script:
perf_db_export_mode = True
perf_db_export_calls = False
perf_db_export_callchains = True
def sample_table(*args):
print(f'sample_table({args})')
def call_path_table(*args):
print(f'call_path_table({args}')
Committer testing:
This test, just introduced by Ian Rogers, now passes, not segfaulting
anymore:
# perf test "perf script tests"
95: perf script tests : Ok
#
Fixes: 0dd5041c9a ("perf addr_location: Add init/exit/copy functions")
Signed-off-by: Ben Gainey <ben.gainey@arm.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Tested-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.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/20231207140911.3240408-1-ben.gainey@arm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This is for a debugging purpose. It'd be useful to see per-instrucion
level success/failure stats.
$ perf annotate --data-type --insn-stat
Annotate Instruction stats
total 264, ok 143 (54.2%), bad 121 (45.8%)
Name : Good Bad
-----------------------------------------------------------
movq : 45 31
movl : 22 11
popq : 0 19
cmpl : 16 3
addq : 8 7
cmpq : 11 3
cmpxchgl : 3 7
cmpxchgq : 8 0
incl : 3 3
movzbl : 4 2
incq : 4 2
decl : 6 0
...
Committer notes:
So these are about being able to find the type for accesses from these
instructions, we should improve the naming, but it is for debugging, we
can improve this later:
@@ -3726,6 +3759,10 @@ struct annotated_data_type *hist_entry__get_data_type(struct hist_entry *he)
continue;
mem_type = find_data_type(ms, ip, op_loc->reg, op_loc->offset);
+ if (mem_type)
+ istat->good++;
+ else
+ istat->bad++;
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: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: linux-toolchains@vger.kernel.org
Cc: linux-trace-devel@vger.kernel.org
Link: https://lore.kernel.org/r/20231213001323.718046-18-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Support data type annotation with new --data-type option. It internally
uses type sort key to collect sample histogram for the type and display
every members like below.
$ perf annotate --data-type
...
Annotate type: 'struct cfs_rq' in [kernel.kallsyms] (13 samples):
============================================================================
samples offset size field
13 0 640 struct cfs_rq {
2 0 16 struct load_weight load {
2 0 8 unsigned long weight;
0 8 4 u32 inv_weight;
};
0 16 8 unsigned long runnable_weight;
0 24 4 unsigned int nr_running;
1 28 4 unsigned int h_nr_running;
...
For simplicity it prints the number of samples per field for now.
But it should be easy to show the overhead percentage instead.
The number at the outer struct is a sum of the numbers of the inner
members. For example, struct cfs_rq got total 13 samples, and 2 came
from the load (struct load_weight) and 1 from h_nr_running. Similarly,
the struct load_weight got total 2 samples and they all came from the
weight field.
I've added two new flags in the symbol_conf for this. The
annotate_data_member is to get the members of the type. This is also
needed for perf report with typeoff sort key. The annotate_data_sample
is to update sample stats for each offset and used only in annotate.
Currently it only support stdio output mode, TUI support can be added
later.
Committer testing:
With the perf.data from the previous csets, a very simple, short
duration one:
# perf annotate --data-type
Annotate type: 'struct list_head' in [kernel.kallsyms] (1 samples):
============================================================================
samples offset size field
1 0 16 struct list_head {
0 0 8 struct list_head* next;
1 8 8 struct list_head* prev;
};
Annotate type: 'char' in [kernel.kallsyms] (1 samples):
============================================================================
samples offset size field
1 0 1 char ;
#
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: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: linux-toolchains@vger.kernel.org
Cc: linux-trace-devel@vger.kernel.org
Link: https://lore.kernel.org/r/20231213001323.718046-15-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The typeoff sort key shows the data type name, offset and the name of
the field. This is useful to see which field in the struct is accessed
most frequently.
$ perf report -s type,typeoff --hierarchy --stdio
...
# Overhead Data Type / Data Type Offset
# ............ ............................
#
...
1.23% struct cfs_rq
0.19% struct cfs_rq +404 (throttle_count)
0.19% struct cfs_rq +0 (load.weight)
0.19% struct cfs_rq +336 (leaf_cfs_rq_list.next)
0.09% struct cfs_rq +272 (propagate)
0.09% struct cfs_rq +196 (removed.nr)
0.09% struct cfs_rq +80 (curr)
0.09% struct cfs_rq +544 (lt_b_children_throttled)
0.06% struct cfs_rq +320 (rq)
Committer testing:
Again with the perf.data from the previous csets:
# perf report --stdio -s type,typeoff
# To display the perf.data header info, please use --header/--header-only options.
#
#
# Total Lost Samples: 0
#
# Samples: 4 of event 'cpu_atom/mem-loads,ldlat=30/P'
# Event count (approx.): 7
#
# Overhead Data Type Data Type Offset
# ........ ......... ................
#
42.86% struct list_head struct list_head +8 (prev)
42.86% (unknown) (unknown) +0 (no field)
14.29% char char +0 (no field)
#
# (Tip: To see callchains in a more compact form: perf report -g folded)
#
# perf report --stdio -s dso,type,typeoff
# To display the perf.data header info, please use --header/--header-only options.
#
#
# Total Lost Samples: 0
#
# Samples: 4 of event 'cpu_atom/mem-loads,ldlat=30/P'
# Event count (approx.): 7
#
# Overhead Shared Object Data Type Data Type Offset
# ........ .................... ......... ................
#
42.86% [kernel.kallsyms] struct list_head struct list_head +8 (prev)
28.57% libc.so.6 (unknown) (unknown) +0 (no field)
14.29% [kernel.kallsyms] char char +0 (no field)
14.29% ld-linux-x86-64.so.2 (unknown) (unknown) +0 (no field)
#
# (Tip: If you have debuginfo enabled, try: perf report -s sym,srcline)
#
#
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: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: linux-toolchains@vger.kernel.org
Cc: linux-trace-devel@vger.kernel.org
Link: https://lore.kernel.org/r/20231213001323.718046-13-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To aggregate accesses to the same data type, add 'data_types' tree in
DSO to maintain data types and find it by name and size.
It might have different data types that happen to have the same name,
so it also compares the size of the type.
Even if it doesn't 100% guarantee, it reduces the possibility of
mis-handling of such conflicts.
And I don't think it's common to have different types with the same
name.
Committer notes:
Very few cases on the Linux kernel, but there are some different types
with the same name, unsure if there is a debug mode in libbpf dedup that
warns about such cases, but there are provisions in pahole for that,
see:
"emit: Notice type shadowing, i.e. multiple types with the same name (enum, struct, union, etc)"
https://git.kernel.org/pub/scm/devel/pahole/pahole.git/commit/?id=4f332dbfd02072e4f410db7bdcda8d6e3422974b
$ pahole --compile > vmlinux.h
$ rm -f a ; make a
cc a.c -o a
$ grep __[0-9] vmlinux.h
union irte__1 {
struct map_info__1;
struct map_info__1 {
struct map_info__1 * next; /* 0 8 */
$
drivers/iommu/amd/amd_iommu_types.h 'union irte'
include/linux/dmar.h 'struct irte'
include/linux/device-mapper.h:
union map_info {
void *ptr;
};
include/linux/mtd/map.h:
struct map_info {
const char *name;
unsigned long size;
resource_size_t phys;
<SNIP>
kernel/events/uprobes.c:
struct map_info {
struct map_info *next;
struct mm_struct *mm;
unsigned long vaddr;
};
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: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: linux-toolchains@vger.kernel.org
Cc: linux-trace-devel@vger.kernel.org
Link: https://lore.kernel.org/r/20231213001323.718046-5-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The find_data_type() is to get a data type from the memory access at the
given address (IP) using a register and an offset.
It requires DWARF debug info in the DSO and searches the list of
variables and function parameters in the scope.
In a pseudo code, it does basically the following:
find_data_type(dso, ip, reg, offset)
{
pc = map__rip_2objdump(ip);
CU = dwarf_addrdie(dso->dwarf, pc);
scopes = die_get_scopes(CU, pc);
for_each_scope(S, scopes) {
V = die_find_variable_by_reg(S, pc, reg);
if (V && V.type == pointer_type) {
T = die_get_real_type(V);
if (offset < T.size)
return T;
}
}
return NULL;
}
Committer notes:
The 'size' variable in check_variable() is 64-bit, so use PRIu64 and
inttypes.h to debug it.
Ditto at find_data_type_die().
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: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: linux-toolchains@vger.kernel.org
Cc: linux-trace-devel@vger.kernel.org
Link: https://lore.kernel.org/r/20231213001323.718046-4-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
