| Commit message (Collapse) | Author | Age | Files | Lines |
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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>
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Display the branch counter histogram in the annotation view.
Press 'B' to display the branch counter's abbreviation list as well.
Samples: 1M of events 'anon group { branch-instructions:ppp, branch-misses }',
4000 Hz, Event count (approx.):
f3 /home/sdp/test/tchain_edit [Percent: local period]
Percent │ IPC Cycle Branch Counter (Average IPC: 1.39, IPC Coverage: 29.4%)
│ 0000000000401755 <f3>:
0.00 0.00 │ endbr64
│ push %rbp
│ mov %rsp,%rbp
│ movl $0x0,-0x4(%rbp)
0.00 0.00 │1.33 3 |A |- | ↓ jmp 25
11.03 11.03 │ 11: mov -0x4(%rbp),%eax
│ and $0x1,%eax
│ test %eax,%eax
17.13 17.13 │2.41 1 |A |- | ↓ je 21
│ addl $0x1,-0x4(%rbp)
21.84 21.84 │2.22 2 |AA |- | ↓ jmp 25
17.13 17.13 │ 21: addl $0x1,-0x4(%rbp)
21.84 21.84 │ 25: cmpl $0x270f,-0x4(%rbp)
11.03 11.03 │0.61 3 |A |- | ↑ jle 11
│ nop
│ pop %rbp
0.00 0.00 │0.24 20 |AA |B | ← ret
Originally-by: Tinghao Zhang <tinghao.zhang@intel.com>
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/20240813160208.2493643-8-kan.liang@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Reusing the existing --total-cycles option to display the branch
counters. Add a new PERF_HPP_REPORT__BLOCK_BRANCH_COUNTER to display
the logged branch counter events. They are shown right after all the
cycle-related annotations.
Extend the 'struct block_info' to store and pass the branch counter
related information.
The annotation_br_cntr_entry() is to print the histogram of each branch
counter event. If the number of logged events is less than 4, the exact
number of the abbr name is printed. Otherwise, using '+' to stands for
more than 3 events.
Assume the number of logged events is less than 4.
The annotation_br_cntr_abbr_list() prints the branch counter's
abbreviation list. Press 'B' to display the list in the TUI mode.
$ perf record -e "{branch-instructions:ppp,branch-misses}:S" -j any,counter
$ perf report --total-cycles --stdio
# To display the perf.data header info, please use --header/--header-only options.
#
#
# Total Lost Samples: 0
#
# Samples: 1M of events 'anon group { branch-instructions:ppp, branch-misses }'
# Event count (approx.): 1610046
#
# Branch counter abbr list:
# branch-instructions:ppp = A
# branch-misses = B
# '-' No event occurs
# '+' Event occurrences may be lost due to branch counter saturated
#
# Sampled Cycles% Sampled Cycles Avg Cycles% Avg Cycles Branch Counter [Program Block Range]
# ............... .............. ........... .......... .............. ..................
#
57.55% 2.5M 0.00% 3 |A |- | ...
25.27% 1.1M 0.00% 2 |AA |- | ...
15.61% 667.2K 0.00% 1 |A |- | ...
0.16% 6.9K 0.81% 575 |A |- | ...
0.16% 6.8K 1.38% 977 |AA |- | ...
0.16% 6.8K 0.04% 28 |AA |B | ...
0.15% 6.6K 1.33% 946 |A |- | ...
0.11% 4.5K 0.06% 46 |AAA+|- | ...
0.10% 4.4K 0.88% 624 |A |- | ...
0.09% 3.7K 0.74% 524 |AAA+|B | ...
With -v applied,
# Sampled Cycles% Sampled Cycles Avg Cycles% Avg Cycles Branch Counter [Program Block Range]
# ............... .............. ........... .......... .............. ..................
#
57.55% 2.5M 0.00% 3 A=1 ,B=- ...
25.27% 1.1M 0.00% 2 A=2 ,B=- ...
15.61% 667.2K 0.00% 1 A=1 ,B=- ...
0.16% 6.9K 0.81% 575 A=1 ,B=- ...
0.16% 6.8K 1.38% 977 A=2 ,B=- ...
0.16% 6.8K 0.04% 28 A=2 ,B=1 ...
0.15% 6.6K 1.33% 946 A=1 ,B=- ...
0.11% 4.5K 0.06% 46 A=3+,B=- ...
0.10% 4.4K 0.88% 624 A=1 ,B=- ...
0.09% 3.7K 0.74% 524 A=3+,B=1 ...
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/20240813160208.2493643-7-kan.liang@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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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>
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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>
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The annotation__pcnt_width() calculates the screen width for the
overhead (percent) area considering event groups properly. Use this
function consistently so that we can make sure it has similar output
in different modes. But there's a difference in stdio and tui output:
stdio uses 8 and tui uses 7 for a percent.
Let's use 8 and adjust the print width in __annotation_line__write()
properly.
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/20240803211332.1107222-4-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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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>
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It's only used in 'perf annotate' output which means functions with actual
samples. No need to consume memory for every symbol ('struct annotation').
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20240404175716.1225482-10-namhyung@kernel.org
Cc: Ian Rogers <irogers@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: LKML <linux-kernel@vger.kernel.org>
Cc: <linux-perf-users@vger.kernel.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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It's only used in 'perf annotate' output which means functions with actual
samples. No need to consume memory for every symbol ('struct annotation').
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>
Link: https://lore.kernel.org/r/20240404175716.1225482-9-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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It's only used in 'perf annotate' output which means functions with actual
samples. No need to consume memory for every symbol ('struct annotation').
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>
Link: https://lore.kernel.org/r/20240404175716.1225482-8-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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It's only used in 'perf annotate' output which means functions with
actual samples. No need to consume memory for every symbol
('struct annotation').
Also move the 'max_line_len' field into it as it's related.
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>
Link: https://lore.kernel.org/r/20240404175716.1225482-7-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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The struct annotated_source.offsets[] is to save pointers to
annotation_line at each offset. We can use annotated_source__get_line()
helper instead so let's get rid of the array.
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>
Link: https://lore.kernel.org/r/20240404175716.1225482-6-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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It's a helper function to get annotation_line at the given offset
without using the offsets array. The goal is to get rid of the
offsets array altogether. It just does the linear search but I
think it's better to save memory as it won't be called in a hot
path.
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>
Link: https://lore.kernel.org/r/20240404175716.1225482-4-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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I found annotation__mark_jump_targets(), annotation__set_offsets()
and annotation__init_column_widths() are only used in the same file.
Let's make them static.
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>
Link: https://lore.kernel.org/r/20240404175716.1225482-3-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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The util/annotate.c code has both disassembly and sample annotation
related codes. Factor out the disasm part so that it can be handled
more easily.
No functional changes intended.
Committer notes:
Add missing include env.h, util.h, bpf-event.h and bpf-util.h to
disasm.c, to fix things like:
util/disasm.c: In function ‘symbol__disassemble_bpf’:
util/disasm.c:1203:9: error: implicit declaration of function ‘perf_exe’ [-Werror=implicit-function-declaration]
1203 | perf_exe(tpath, sizeof(tpath));
| ^~~~~~~~
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.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/20240329215812.537846-4-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Likewise, add ins__is_nop() to check if the current instruction is NOP.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.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/20240329215812.537846-3-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Add a segment field in the struct annotated_insn_loc and save it for the
segment based addressing like %gs:0x28. For simplicity it now handles
%gs register only.
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>
Link: https://lore.kernel.org/r/20240319055115.4063940-17-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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The annotate_get_basic_blocks() is to find a list of basic blocks from
the source instruction to the destination instruction in a function.
It'll be used to find variables in a scope. Use BFS (Breadth First
Search) to find a shortest path to carry the variable/register state
minimally.
Also change find_disasm_line() to be used in annotate_get_basic_blocks()
and add 'allow_update' argument to control if it can update the IP.
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>
Link: https://lore.kernel.org/r/20240319055115.4063940-8-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Reviewed-by: Ian Rogers <irogers@google.com>
Reviewed-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20240304230815.1440583-5-namhyung@kernel.org
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It's not used anymore and the code is coverted to use a hash map. Now
sym_hist has a static size, so no need to have sizeof_sym_hist in the
struct annotated_source.
Reviewed-by: Ian Rogers <irogers@google.com>
Reviewed-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20240304230815.1440583-4-namhyung@kernel.org
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Use annotated_source.samples hashmap instead of addr array in the
struct sym_hist.
Reviewed-by: Ian Rogers <irogers@google.com>
Reviewed-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20240304230815.1440583-3-namhyung@kernel.org
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Now symbol histogram uses an array to save per-offset sample counts.
But it wastes a lot of memory if the symbol has a few samples only.
Add a hashmap to save values only for actual samples.
For now, it has duplicate histogram (one in the existing array and
another in the new hash map). Once it can convert to use the hash
in all places, we can get rid of the array later.
Reviewed-by: Ian Rogers <irogers@google.com>
Reviewed-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20240304230815.1440583-2-namhyung@kernel.org
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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>
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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>
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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>
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It's the function to find out the type info from the given sample data
and will be called from the hist_entry sort logic when 'type' sort key
is used.
It first calls objdump to disassemble the instructions and figure out
information about memory access at the location. Maybe we can do it
better by analyzing the instruction directly, but I'll leave it for
later work.
The memory access is determined by checking instruction operands to
have "(" and then extract register name and offset. It'll return NULL
if no data type is found.
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/20231213001323.718046-8-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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The annotate_get_insn_location() is to get the detailed information of
instruction locations like registers and offset. It has source and
target operands locations in an array. Each operand can have a register
and an offset. The offset is meaningful when mem_ref flag is set.
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/20231213001323.718046-7-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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The evsel__get_arch() is to get architecture info from the environment.
It'll be used by other places later so let's factor it out.
Also add arch__is() to check the arch info by name.
Committer notes:
"get" is usually associated with refcounting, so we better rename this
at some point to a better name.
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/20231213001323.718046-6-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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It doesn't need the option in the struct annotation which is allocated
for each symbol. It can directly use the global options and save 8
bytes per symbol.
Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20231128175441.721579-9-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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So that it can get rid of the unused data.
Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20231128175441.721579-8-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Now it only cares about the global options so it can just handle it
without the argument.
Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20231128175441.721579-7-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Now it can use the global options and no need save local browser
options separately.
Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20231128175441.721579-6-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Now it can directly use the global options and no need to pass it as an
argument.
Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20231128175441.721579-5-namhyung@kernel.org
[ Fixup build with GTK2=1 ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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The annotation options are to control the behavior of objdump and the
output. It's basically used by 'perf annotate' but 'perf report' and
'perf top' can call it on TUI dynamically.
But it doesn't need to have a copy of annotation options in many places.
As most of the work is done in the util/annotate.c file, add a global
variable and set/use it instead of having their own copies.
Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20231128175441.721579-2-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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It needs to check all possible information in an instruction. Let's add
a field indicating if the operand has multiple registers. I'll be used
to search type information like in an array access on x86 like:
mov 0x10(%rax,%rbx,8), %rcx
-------------
here
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/20231012035111.676789-3-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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ins_operands'
Thoese two fields are used only for the jump_ops, so move them into the
union to save some bytes. Also add jump__delete() callback not to free
the fields as they didn't allocate new strings.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Huacai Chen <chenhuacai@kernel.org>
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 (Google) <mhiramat@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: WANG Rui <wangrui@loongson.cn>
Cc: linux-toolchains@vger.kernel.org
Cc: linux-trace-devel@vger.kernel.org
Link: https://lore.kernel.org/r/20231110000012.3538610-3-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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annotated_source'
The offsets array keeps pointers to 'struct annotation_line' entries
which are available in the 'struct annotated_source'. Let's move it to
there.
Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20231103191907.54531-6-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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to 'struct annotated_source'
Some fields in the 'struct annotation' are only used with 'struct
annotated_source' so better to be moved there in order to reduce memory
consumption for other symbols.
Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20231103191907.54531-5-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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annotated_branch'
The max_coverage field is only used when branch stack info is available
so it'd be natural to move to 'struct annotated_branch'.
Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20231103191907.54531-4-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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The cycles info is only meaningful when sample has branch stacks. To
save the memory for normal cases, move those fields to a new 'struct
annotated_branch' and dynamically allocate it when needed. Also move
cycles_hist from annotated_source as it's related here.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20231103191907.54531-3-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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annotation_line'
The cycles info is used only when branch stack is provided. Separate
them from 'struct annotation_line' into a separate struct and lazy
allocate them to save some memory.
Committer notes:
Make annotation__compute_ipc() check if the lazy allocation works,
bailing out if so, its callers already do error checking and
propagation.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20231103191907.54531-2-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Remove the "struct mutex lock" variable from annotation that is
allocated per symbol. This removes in the region of 40 bytes per
symbol allocation. Use a sharded mutex where the number of shards is
set to the number of CPUs. Assuming good hashing of the annotation
(done based on the pointer), this means in order to contend there
needs to be more threads than CPUs, which is not currently true in any
perf command. Were contention an issue it is straightforward to
increase the number of shards in the mutex.
On my Debian/glibc based machine, this reduces the size of struct
annotation from 136 bytes to 96 bytes, or nearly 30%.
Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Andres Freund <andres@anarazel.de>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Yuan Can <yuancan@huawei.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Link: https://lore.kernel.org/r/20230615040715.2064350-2-irogers@google.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
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Make struct annotation_options own the strings objdump_path and
disassembler_style, freeing them on exit. Add missing strdup for
disassembler_style when read from a config file.
Committer notes:
Converted free(obj->member) to zfree(&obj->member) in
annotation_options__exit()
Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andres Freund <andres@anarazel.de>
Cc: German Gomez <german.gomez@arm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.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: Nathan Chancellor <nathan@kernel.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sandipan Das <sandipan.das@amd.com>
Cc: Tom Rix <trix@redhat.com>
Cc: llvm@lists.linux.dev
Link: https://lore.kernel.org/r/20230328235543.1082207-2-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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The annotation__default_options global variable was used to initialize
annotation_options. Switch to the init/exit pattern as later changes
will give ownership over strings and this will be necessary to avoid
memory leaks.
Committer note:
Fix the GTK2=1 build, hist_entry__gtk_annotate() needs to receive a
'struct annotation_options' pointer.
Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andres Freund <andres@anarazel.de>
Cc: German Gomez <german.gomez@arm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.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: Nathan Chancellor <nathan@kernel.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sandipan Das <sandipan.das@amd.com>
Cc: Tom Rix <trix@redhat.com>
Cc: llvm@lists.linux.dev
Link: https://lore.kernel.org/r/20230328235543.1082207-2-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Handle 'f' key to toggle the display offset and full address. Obviously
it only works when users set to see disassembler output ('o' key). It'd
be useful when users want to see the full virtual address in the TUI
annotate browser.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: https://lore.kernel.org/r/20220923173142.805896-5-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Switch to the use of mutex wrappers that provide better error checking.
Signed-off-by: Ian Rogers <irogers@google.com>
Reviewed-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexandre Truong <alexandre.truong@arm.com>
Cc: Alexey Bayduraev <alexey.v.bayduraev@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andres Freund <andres@anarazel.de>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: André Almeida <andrealmeid@igalia.com>
Cc: Athira Jajeev <atrajeev@linux.vnet.ibm.com>
Cc: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Cc: Colin Ian King <colin.king@intel.com>
Cc: Dario Petrillo <dario.pk1@gmail.com>
Cc: Darren Hart <dvhart@infradead.org>
Cc: Dave Marchevsky <davemarchevsky@fb.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Fangrui Song <maskray@google.com>
Cc: Hewenliang <hewenliang4@huawei.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jason Wang <wangborong@cdjrlc.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Kim Phillips <kim.phillips@amd.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Martin Liška <mliska@suse.cz>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Pavithra Gurushankar <gpavithrasha@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Quentin Monnet <quentin@isovalent.com>
Cc: Ravi Bangoria <ravi.bangoria@amd.com>
Cc: Remi Bernon <rbernon@codeweavers.com>
Cc: Riccardo Mancini <rickyman7@gmail.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Cc: Tom Rix <trix@redhat.com>
Cc: Weiguo Li <liwg06@foxmail.com>
Cc: Wenyu Liu <liuwenyu7@huawei.com>
Cc: William Cohen <wcohen@redhat.com>
Cc: Zechuan Chen <chenzechuan1@huawei.com>
Cc: bpf@vger.kernel.org
Cc: llvm@lists.linux.dev
Cc: yaowenbin <yaowenbin1@huawei.com>
Link: https://lore.kernel.org/r/20220826164242.43412-13-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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The exit function fixes a memory leak with the src field as detected by
leak sanitizer. An example of which is:
Indirect leak of 25133184 byte(s) in 207 object(s) allocated from:
#0 0x7f199ecfe987 in __interceptor_calloc libsanitizer/asan/asan_malloc_linux.cpp:154
#1 0x55defe638224 in annotated_source__alloc_histograms util/annotate.c:803
#2 0x55defe6397e4 in symbol__hists util/annotate.c:952
#3 0x55defe639908 in symbol__inc_addr_samples util/annotate.c:968
#4 0x55defe63aa29 in hist_entry__inc_addr_samples util/annotate.c:1119
#5 0x55defe499a79 in hist_iter__report_callback tools/perf/builtin-report.c:182
#6 0x55defe7a859d in hist_entry_iter__add util/hist.c:1236
#7 0x55defe49aa63 in process_sample_event tools/perf/builtin-report.c:315
#8 0x55defe731bc8 in evlist__deliver_sample util/session.c:1473
#9 0x55defe731e38 in machines__deliver_event util/session.c:1510
#10 0x55defe732a23 in perf_session__deliver_event util/session.c:1590
#11 0x55defe72951e in ordered_events__deliver_event util/session.c:183
#12 0x55defe740082 in do_flush util/ordered-events.c:244
#13 0x55defe7407cb in __ordered_events__flush util/ordered-events.c:323
#14 0x55defe740a61 in ordered_events__flush util/ordered-events.c:341
#15 0x55defe73837f in __perf_session__process_events util/session.c:2390
#16 0x55defe7385ff in perf_session__process_events util/session.c:2420
...
Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Martin Liška <mliska@suse.cz>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: https://lore.kernel.org/r/20211112035124.94327-3-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Right now, when Line numbers are displayed, one can't easily find a
source file that the line corresponds to.
When a source line is selected and 'l' is pressed, full source file
location is displayed in perf UI footer line. The hotkey works only for
source code lines.
Signed-off-by: Martin Liška <mliska@suse.cz>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Link: http://lore.kernel.org/lkml/25a6384f-d862-5dda-4fec-8f0555599c75@suse.cz
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Considering the following testcase:
int
foo(int a, int b)
{
for (unsigned i = 0; i < 1000000000; i++)
a += b;
return a;
}
int main()
{
foo (3, 4);
return 0;
}
'perf annotate' displays:
86.52 │40055e: → ja 40056c <foo(int, int)+0x26>
13.37 │400560: mov -0x18(%rbp),%eax
│400563: add %eax,-0x14(%rbp)
│400566: addl $0x1,-0x4(%rbp)
0.11 │40056a: → jmp 400557 <foo(int, int)+0x11>
│40056c: mov -0x14(%rbp),%eax
│40056f: pop %rbp
and the 'ja 40056c' does not link to the location in the function. It's
caused by fact that comma is wrongly parsed, it's part of function
signature.
With my patch I see:
86.52 │ ┌──ja 26
13.37 │ │ mov -0x18(%rbp),%eax
│ │ add %eax,-0x14(%rbp)
│ │ addl $0x1,-0x4(%rbp)
0.11 │ │↑ jmp 11
│26:└─→mov -0x14(%rbp),%eax
and 'o' output prints:
86.52 │4005┌── ↓ ja 40056c <foo(int, int)+0x26>
13.37 │4005│0: mov -0x18(%rbp),%eax
│4005│3: add %eax,-0x14(%rbp)
│4005│6: addl $0x1,-0x4(%rbp)
0.11 │4005│a: ↑ jmp 400557 <foo(int, int)+0x11>
│4005└─→ mov -0x14(%rbp),%eax
On the contrary, compiling the very same file with gcc -x c, the parsing
is fine because function arguments are not displayed:
jmp 400543 <foo+0x1d>
Committer testing:
Before:
$ cat cpp_args_annotate.c
int
foo(int a, int b)
{
for (unsigned i = 0; i < 1000000000; i++)
a += b;
return a;
}
int main()
{
foo (3, 4);
return 0;
}
$ gcc --version |& head -1
gcc (GCC) 10.2.1 20201125 (Red Hat 10.2.1-9)
$ gcc -g cpp_args_annotate.c -o cpp_args_annotate
$ perf record ./cpp_args_annotate
[ perf record: Woken up 2 times to write data ]
[ perf record: Captured and wrote 0.275 MB perf.data (7188 samples) ]
$ perf annotate --stdio2 foo
Samples: 7K of event 'cycles:u', 4000 Hz, Event count (approx.): 7468429289, [percent: local period]
foo() /home/acme/c/cpp_args_annotate
Percent
0000000000401106 <foo>:
foo():
int
foo(int a, int b)
{
push %rbp
mov %rsp,%rbp
mov %edi,-0x14(%rbp)
mov %esi,-0x18(%rbp)
for (unsigned i = 0; i < 1000000000; i++)
movl $0x0,-0x4(%rbp)
↓ jmp 1d
a += b;
13.45 13: mov -0x18(%rbp),%eax
add %eax,-0x14(%rbp)
for (unsigned i = 0; i < 1000000000; i++)
addl $0x1,-0x4(%rbp)
0.09 1d: cmpl $0x3b9ac9ff,-0x4(%rbp)
86.46 ↑ jbe 13
return a;
mov -0x14(%rbp),%eax
}
pop %rbp
← retq
$
I.e. works for C, now lets switch to C++:
$ g++ -g cpp_args_annotate.c -o cpp_args_annotate
$ perf record ./cpp_args_annotate
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.268 MB perf.data (6976 samples) ]
$ perf annotate --stdio2 foo
Samples: 6K of event 'cycles:u', 4000 Hz, Event count (approx.): 7380681761, [percent: local period]
foo() /home/acme/c/cpp_args_annotate
Percent
0000000000401106 <foo(int, int)>:
foo(int, int):
int
foo(int a, int b)
{
push %rbp
mov %rsp,%rbp
mov %edi,-0x14(%rbp)
mov %esi,-0x18(%rbp)
for (unsigned i = 0; i < 1000000000; i++)
movl $0x0,-0x4(%rbp)
cmpl $0x3b9ac9ff,-0x4(%rbp)
86.53 → ja 40112c <foo(int, int)+0x26>
a += b;
13.32 mov -0x18(%rbp),%eax
0.00 add %eax,-0x14(%rbp)
for (unsigned i = 0; i < 1000000000; i++)
addl $0x1,-0x4(%rbp)
0.15 → jmp 401117 <foo(int, int)+0x11>
return a;
mov -0x14(%rbp),%eax
}
pop %rbp
← retq
$
Reproduced.
Now with this patch:
Reusing the C++ built binary, as we can see here:
$ readelf -wi cpp_args_annotate | grep producer
<c> DW_AT_producer : (indirect string, offset: 0x2e): GNU C++14 10.2.1 20201125 (Red Hat 10.2.1-9) -mtune=generic -march=x86-64 -g
$
And furthermore:
$ file cpp_args_annotate
cpp_args_annotate: ELF 64-bit LSB executable, x86-64, version 1 (SYSV), dynamically linked, interpreter /lib64/ld-linux-x86-64.so.2, BuildID[sha1]=4fe3cab260204765605ec630d0dc7a7e93c361a9, for GNU/Linux 3.2.0, with debug_info, not stripped
$ perf buildid-list -i cpp_args_annotate
4fe3cab260204765605ec630d0dc7a7e93c361a9
$ perf buildid-list | grep cpp_args_annotate
4fe3cab260204765605ec630d0dc7a7e93c361a9 /home/acme/c/cpp_args_annotate
$
It now works:
$ perf annotate --stdio2 foo
Samples: 6K of event 'cycles:u', 4000 Hz, Event count (approx.): 7380681761, [percent: local period]
foo() /home/acme/c/cpp_args_annotate
Percent
0000000000401106 <foo(int, int)>:
foo(int, int):
int
foo(int a, int b)
{
push %rbp
mov %rsp,%rbp
mov %edi,-0x14(%rbp)
mov %esi,-0x18(%rbp)
for (unsigned i = 0; i < 1000000000; i++)
movl $0x0,-0x4(%rbp)
11: cmpl $0x3b9ac9ff,-0x4(%rbp)
86.53 ↓ ja 26
a += b;
13.32 mov -0x18(%rbp),%eax
0.00 add %eax,-0x14(%rbp)
for (unsigned i = 0; i < 1000000000; i++)
addl $0x1,-0x4(%rbp)
0.15 ↑ jmp 11
return a;
26: mov -0x14(%rbp),%eax
}
pop %rbp
← retq
$
Signed-off-by: Martin Liška <mliska@suse.cz>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Link: http://lore.kernel.org/lkml/13e1a405-edf9-e4c2-4327-a9b454353730@suse.cz
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array
member[1][2], introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning in
case the flexible array does not occur last in the structure, which will
help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by this
change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
sizeof(flexible-array-member) triggers a warning because flexible array
members have incomplete type[1]. There are some instances of code in
which the sizeof operator is being incorrectly/erroneously applied to
zero-length arrays and the result is zero. Such instances may be hiding
some bugs. So, this work (flexible-array member conversions) will also
help to get completely rid of those sorts of issues.
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Gustavo A. R. Silva <gustavo@embeddedor.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20200515172926.GA31976@embeddedor
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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