When perf report with annotation for a symbol, press 's' and 'T', then exit
the annotate browser. Once annotate the same symbol, the annotate browser
will crash.
The browser.arch was required to be correctly updated when data type
feature was enabled by 'T'. Usually it was initialized by symbol__annotate2
function. If a symbol has already been correctly annotated at the first
time, it should not call the symbol__annotate2 function again, thus the
browser.arch will not get initialized. Then at the second time to show the
annotate browser, the data type needs to be displayed but the browser.arch
is empty.
Stack trace as below:
Perf: Segmentation fault
-------- backtrace --------
#0 0x55d365 in ui__signal_backtrace setup.c:0
#1 0x7f5ff1a3e930 in __restore_rt libc.so.6[3e930]
#2 0x570f08 in arch__is perf[570f08]
#3 0x562186 in annotate_get_insn_location perf[562186]
#4 0x562626 in __hist_entry__get_data_type annotate.c:0
#5 0x56476d in annotation_line__write perf[56476d]
#6 0x54e2db in annotate_browser__write annotate.c:0
#7 0x54d061 in ui_browser__list_head_refresh perf[54d061]
#8 0x54dc9e in annotate_browser__refresh annotate.c:0
#9 0x54c03d in __ui_browser__refresh browser.c:0
#10 0x54ccf8 in ui_browser__run perf[54ccf8]
#11 0x54eb92 in __hist_entry__tui_annotate perf[54eb92]
#12 0x552293 in do_annotate hists.c:0
#13 0x55941c in evsel__hists_browse hists.c:0
#14 0x55b00f in evlist__tui_browse_hists perf[55b00f]
#15 0x42ff02 in cmd_report perf[42ff02]
#16 0x494008 in run_builtin perf.c:0
#17 0x494305 in handle_internal_command perf.c:0
#18 0x410547 in main perf[410547]
#19 0x7f5ff1a295d0 in __libc_start_call_main libc.so.6[295d0]
#20 0x7f5ff1a29680 in __libc_start_main@@GLIBC_2.34 libc.so.6[29680]
#21 0x410b75 in _start perf[410b75]
Fixes: 1d4374afd0 ("perf annotate: Add 'T' hot key to toggle data type display")
Reviewed-by: James Clark <james.clark@linaro.org>
Tested-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Tianyou Li <tianyou.li@intel.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Recently it uses llvm and capstone to speed up annotation or disassembly
of instructions. But they don't support source code view yet. Until it
fixed, we can force to use objdump for source code annotation.
To prevent performance loss, it's disabled by default and turned it on
when user requests it in TUI by pressing 's' key.
Acked-by: Ian Rogers <irogers@google.com>
Link: https://lore.kernel.org/r/20250625230339.702610-1-namhyung@kernel.org
Reported-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Sometimes it's useful to see both instructions and their data type
together. Let's extend the annotate code to use data type profiling
functions.
To make it easy to pass more argument, introduce a struct to carry
necessary information together. Also add a new annotation_option called
'code_with_type' to control the behavior. This is not enabled yet but
it'll be set later from the command line.
For simplicity, this is implemented for --stdio only.
Reviewed-by: Ian Rogers <irogers@google.com>
Link: https://lore.kernel.org/r/20250310224925.799005-7-namhyung@kernel.org
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
It's a prepartion to support code annotation and data type
annotation at the same time. Data type annotation needs more
information in the hist_entry so it needs to be passed deeper.
Also rename a function with the same name in the builtin-annotate.c
to hist_entry__stdio_annotate since it matches better to the command
line option. And change the condition inside to be simpler.
Reviewed-by: Ian Rogers <irogers@google.com>
Link: https://lore.kernel.org/r/20250310224925.799005-5-namhyung@kernel.org
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
When doing "perf annotate", perf tool provides option to
use specific disassembler like llvm/objdump/capstone. The
order picked is to use llvm first and if that fails fallback
to objdump ie to use PERF_DISASM_LLVM, PERF_DISASM_CAPSTONE
and PERF_DISASM_OBJDUMP
In powerpc, when using "data type" sort keys, first preferred
approach is to read the raw instruction from the DSO. In objdump
is specified in "--objdump" option, it picks the symbol disassemble
using objdump. Currently disasm_line__parse_powerpc() function
uses length of the "line" to determine if objdump is used.
But there are few cases, where if objdump doesn't recognise the
instruction, the disassembled string will be empty.
Example:
134cdc: c4 05 82 41 beq 1352a0 <getcwd+0x6e0>
134ce0: ac 00 8e 40 bne cr3,134d8c <getcwd+0x1cc>
134ce4: 0f 00 10 04 pld r9,1028308
====>134ce8: d4 b0 20 e5
134cec: 16 00 40 39 li r10,22
134cf0: 48 01 21 ea ld r17,328(r1)
So depending on length of line will give bad results.
Add a new filed to annotation options structure,
"struct annotation_options" to save the disassembler used.
Use this info to determine if disassembly is done while
parsing the disasm line.
Reported-by: Tejas Manhas <Tejas.Manhas1@ibm.com>
Signed-off-by: Athira Rajeev <atrajeev@linux.ibm.com>
Tested-By: Venkat Rao Bagalkote <venkat88@linux.ibm.com>
Link: https://lore.kernel.org/r/20250304154114.62093-1-atrajeev@linux.ibm.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Prior to this change a string was used which could cause issues with
an unrecognized disassembler in symbol__disassembler. Change to
initializing an array of perf_disassembler enum values. If a value
already exists then adding it a second time is ignored to avoid array
out of bounds problems present in the previous code, it also allows a
statically sized array and removes memory allocation needs. Errors in
the disassembler string are reported when the config is parsed during
perf annotate or perf top start up. If the array is uninitialized
after processing the config file the default llvm, capstone then
objdump values are added but without a need to parse a string.
Fixes: a6e8a58de6 ("perf disasm: Allow configuring what disassemblers to use")
Closes: https://lore.kernel.org/lkml/CAP-5=fUdfCyxmEiTpzS2uumUp3-SyQOseX2xZo81-dQtWXj6vA@mail.gmail.com/
Signed-off-by: Ian Rogers <irogers@google.com>
Tested-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20250124043856.1177264-1-irogers@google.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
The perf tools annotation code used for a long time parsing the output
of binutils's objdump (or its reimplementations, like llvm's) to then
parse and augment it with samples, allow navigation, etc.
More recently disassemblers from the capstone and llvm (libraries, not
parsing the output of tools using those libraries to mimic binutils's
objdump output) were introduced.
So when all those methods are available, there is a static preference
for a series of attempts of disassembling a binary, with the 'llvm,
capstone, objdump' sequence being hard coded.
This patch allows users to change that sequence, specifying via a 'perf
config' 'annotate.disassemblers' entry which and in what order
disassemblers should be attempted.
As alluded to in the comments in the source code of this series, this
flexibility is useful for users and developers alike, elliminating the
requirement to rebuild the tool with some specific set of libraries to
see how the output of disassembling would be for one of these methods.
root@x1:~# rm -f ~/.perfconfig
root@x1:~# perf annotate -v --stdio2 update_load_avg
<SNIP>
symbol__disassemble:
filename=/usr/lib/debug/lib/modules/6.11.4-201.fc40.x86_64/vmlinux,
sym=update_load_avg, start=0xffffffffb6148fe0, en>
annotating [0x6ff7170]
/usr/lib/debug/lib/modules/6.11.4-201.fc40.x86_64/vmlinux :
[0x7407ca0] update_load_avg
Disassembled with llvm
annotate.disassemblers=llvm,capstone,objdump
Samples: 66 of event 'cpu_atom/cycles/P', 10000 Hz,
Event count (approx.): 5185444, [percent: local period]
update_load_avg()
/usr/lib/debug/lib/modules/6.11.4-201.fc40.x86_64/vmlinux
Percent 0xffffffff81148fe0 <update_load_avg>:
1.61 pushq %r15
pushq %r14
1.00 pushq %r13
movl %edx,%r13d
1.90 pushq %r12
pushq %rbp
movq %rsi,%rbp
pushq %rbx
movq %rdi,%rbx
subq $0x18,%rsp
15.14 movl 0x1a4(%rdi),%eax
root@x1:~# perf config annotate.disassemblers=capstone
root@x1:~# cat ~/.perfconfig
# this file is auto-generated.
[annotate]
disassemblers = capstone
root@x1:~#
root@x1:~# perf annotate -v --stdio2 update_load_avg
<SNIP>
Disassembled with capstone
annotate.disassemblers=capstone
Samples: 66 of event 'cpu_atom/cycles/P', 10000 Hz,
Event count (approx.): 5185444, [percent: local period]
update_load_avg()
/usr/lib/debug/lib/modules/6.11.4-201.fc40.x86_64/vmlinux
Percent 0xffffffff81148fe0 <update_load_avg>:
1.61 pushq %r15
pushq %r14
1.00 pushq %r13
movl %edx,%r13d
1.90 pushq %r12
pushq %rbp
movq %rsi,%rbp
pushq %rbx
movq %rdi,%rbx
subq $0x18,%rsp
15.14 movl 0x1a4(%rdi),%eax
root@x1:~# perf config annotate.disassemblers=objdump,capstone
root@x1:~# perf config annotate.disassemblers
annotate.disassemblers=objdump,capstone
root@x1:~# cat ~/.perfconfig
# this file is auto-generated.
[annotate]
disassemblers = objdump,capstone
root@x1:~# perf annotate -v --stdio2 update_load_avg
Executing: objdump --start-address=0xffffffff81148fe0 \
--stop-address=0xffffffff811497aa \
-d --no-show-raw-insn -S -C "$1"
Disassembled with objdump
annotate.disassemblers=objdump,capstone
Samples: 66 of event 'cpu_atom/cycles/P', 10000 Hz,
Event count (approx.): 5185444, [percent: local period]
update_load_avg()
/usr/lib/debug/lib/modules/6.11.4-201.fc40.x86_64/vmlinux
Percent
Disassembly of section .text:
ffffffff81148fe0 <update_load_avg>:
#define DO_ATTACH 0x4
ffffffff81148fe0 <update_load_avg>:
#define DO_ATTACH 0x4
#define DO_DETACH 0x8
/* Update task and its cfs_rq load average */
static inline void update_load_avg(struct cfs_rq *cfs_rq,
struct sched_entity *se,
int flags)
{
1.61 push %r15
push %r14
1.00 push %r13
mov %edx,%r13d
1.90 push %r12
push %rbp
mov %rsi,%rbp
push %rbx
mov %rdi,%rbx
sub $0x18,%rsp
}
/* rq->task_clock normalized against any time
this cfs_rq has spent throttled */
static inline u64 cfs_rq_clock_pelt(struct cfs_rq *cfs_rq)
{
if (unlikely(cfs_rq->throttle_count))
15.14 mov 0x1a4(%rdi),%eax
root@x1:~#
After adding a way to select the disassembler from the command line a
'perf test' comparing the output of the various diassemblers should be
introduced, to test these codebases.
Acked-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Steinar H. Gunderson <sesse@google.com>
Link: https://lore.kernel.org/r/20241111151734.1018476-4-acme@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When annotating a basic block, it's useful to display the occurrences
of other events in the block.
The branch counter feature is only available for newer Intel platforms.
So a dedicated option to display the branch counters is not introduced.
Reuse the existing --total-cycles option, which triggers the annotation
of a basic block and displays the cycle-related annotation.
When the branch counters information is available, the branch counters
are automatically appended after all the cycle-related annotation.
Accounting the branch counters as well when accounting the cycles in
hist__account_cycles().
In 'struct annotated_branch', introduce a br_cntr array to save the
accumulation of each branch counter.
In a sample, all the branch counters for a branch are saved in a u64
space.
Because the saturation of a branch counter is small, e.g., for Intel
Sierra Forest, the saturation is only 3.
Add ANNOTATION__BR_CNTR_SATURATED_FLAG to indicate if a branch counter
once saturated. That can be used to indicate a potential event lost
because of the saturation.
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Acked-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: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: https://lore.kernel.org/r/20240813160208.2493643-5-kan.liang@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
In find_data_type(), it creates and deletes a debug info whenver it
tries to find data type for a sample. This is inefficient and it most
likely accesses the same binary again and again.
Let's add a single entry cache the debug info structure for the last DSO.
Depending on sample data, it usually gives me 2~3x (and sometimes more)
speed ups.
Note that this will introduce a little difference in the output due to
the order of checking stack operations. It used to check the stack ops
before checking the availability of debug info but I moved it after the
symbol check. So it'll report stack operations in DSOs without debug
info as unknown. But I think it's ok and better to have the checking
near the caching logic.
Committer testing:
root@x1:~# perf mem record -a sleep 5s
root@x1:~# perf evlist
cpu_atom/mem-loads,ldlat=30/P
cpu_atom/mem-stores/P
dummy:u
root@x1:~# diff -u before after
--- before 2024-08-08 09:33:53.880780784 -0300
+++ after 2024-08-08 09:35:13.917325041 -0300
@@ -81,8 +81,8 @@
# Overhead Data Type
# ........ .........
#
- 55.43% (unknown)
- 11.61% (stack operation)
+ 55.56% (unknown)
+ 11.48% (stack operation)
4.93% struct pcpu_hot
3.26% unsigned int
2.48% struct
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: Athira Rajeev <atrajeev@linux.vnet.ibm.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/20240805234648.1453689-1-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Currently, the perf tool infrastructure uses the disasm_line__parse
function to parse disassembled line.
Example snippet from objdump:
objdump --start-address=<address> --stop-address=<address> -d --no-show-raw-insn -C <vmlinux>
c0000000010224b4: lwz r10,0(r9)
This line "lwz r10,0(r9)" is parsed to extract instruction name,
registers names and offset.
In powerpc, the approach for data type profiling uses raw instruction
instead of result from objdump to identify the instruction category and
extract the source/target registers.
Example: 38 01 81 e8 ld r4,312(r1)
Here "38 01 81 e8" is the raw instruction representation. Add function
"disasm_line__parse_powerpc" to handle parsing of raw instruction.
Also update "struct disasm_line" to save the binary code/
With the change, function captures:
line -> "38 01 81 e8 ld r4,312(r1)"
raw instruction "38 01 81 e8"
Raw instruction is used later to extract the reg/offset fields. Macros
are added to extract opcode and register fields. "struct disasm_line"
is updated to carry union of "bytes" and "raw_insn" of 32 bit to carry raw
code (raw).
Function "disasm_line__parse_powerpc fills the raw instruction hex value
and can use macros to get opcode. There is no changes in existing code
paths, which parses the disassembled code. The size of raw instruction
depends on architecture.
In case of powerpc, the parsing the disasm line needs to handle cases
for reading binary code directly from DSO as well as parsing the objdump
result. Hence adding the logic into separate function instead of
updating "disasm_line__parse". The architecture using the instruction
name and present approach is not altered. Since this approach targets
powerpc, the macro implementation is added for powerpc as of now.
Since the disasm_line__parse is used in other cases (perf annotate) and
not only data tye profiling, the powerpc callback includes changes to
work with binary code as well as mnemonic representation.
Also in case if the DSO read fails and libcapstone is not supported, the
approach fallback to use objdump as option. Hence as option, patch has
changes to ensure objdump option also works well.
Reviewed-by: Kajol Jain <kjain@linux.ibm.com>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Tested-by: Kajol Jain <kjain@linux.ibm.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Akanksha J N <akanksha@linux.ibm.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Disha Goel <disgoel@linux.vnet.ibm.com>
Cc: Hari Bathini <hbathini@linux.ibm.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Segher Boessenkool <segher@kernel.crashing.org>
Link: https://lore.kernel.org/lkml/20240718084358.72242-5-atrajeev@linux.vnet.ibm.com
[ Add check for strndup() result ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
