Hello,
There are roughly two modes in the perf annotate. One is normal code
annotation and the other is data type annotation. I'm proposing a new
way to combine the code and data annotation together.
With this option, "# data-type: <name> [offset (field)]" part will be
added when it found a data type for the given instruction. This is
for every instruction in the function regardless whether it has a
sample or not.
This will be useful to understand function level data access patterns.
Currently it only works with --stdio, but I can add it to TUI later.
v2 changes)
* fix typos in the cover letter (Ian)
* fix a build error when !HAVE_LIBDW_SUPPORT
* add Reviewed-by from Ian
v1: https://lore.kernel.org/r/20250303173807.1765098-1-namhyung@kernel.org
Here's an example output.
$ perf annotate --code-with-type --stdio
...
Percent | Source code & Disassembly of elf for cpu/mem-loads,ldlat=30/P (4 samples, percent: local period)
----------------------------------------------------------------------------------------------------------------
: 0 0xffffffff81bb7060 <__schedule>:
0.00 : ffffffff81bb7060: pushq %rbp # data-type: (stack operation)
0.00 : ffffffff81bb7061: movq %rsp, %rbp
0.00 : ffffffff81bb7064: pushq %r15 # data-type: (stack operation)
0.00 : ffffffff81bb7066: pushq %r14 # data-type: (stack operation)
0.00 : ffffffff81bb7068: pushq %r13 # data-type: (stack operation)
0.00 : ffffffff81bb706a: pushq %r12 # data-type: (stack operation)
0.00 : ffffffff81bb706c: pushq %rbx # data-type: (stack operation)
0.00 : ffffffff81bb706d: movq $0x33180, %rbx
0.00 : ffffffff81bb7074: movq %rbx, %r12
0.00 : ffffffff81bb7077: subq $0x38, %rsp
0.00 : ffffffff81bb707b: movl %edi, -0x5c(%rbp) # data-type: unsigned int +0
0.00 : ffffffff81bb707e: movq %gs:0x28, %rax # data-type: (stack canary)
0.00 : ffffffff81bb7087: movq %rax, -0x30(%rbp) # data-type: (stack canary)
0.00 : ffffffff81bb708b: xorl %eax, %eax
0.00 : ffffffff81bb708d: movq $0x0, -0x58(%rbp) # data-type: struct rq_flags +0 (flags)
0.00 : ffffffff81bb7095: movq $0x0, -0x50(%rbp) # data-type: struct rq_flags +0x8 (clock_update_flags)
0.00 : ffffffff81bb709d: callq 0xffffffff81baa100 <debug_smp_processor_id> # data-type: (stack operation)
0.00 : ffffffff81bb70a2: cltq
0.00 : ffffffff81bb70a4: addq -0x7dcf0500(,%rax,8), %r12 # data-type: long unsigned int[] +0
0.00 : ffffffff81bb70ac: movq 0x960(%r12), %r13 # data-type: struct rq +0x960 (curr)
0.00 : ffffffff81bb70b4: movq 0x20(%r13), %rax # data-type: struct task_struct +0x20 (stack)
0.00 : ffffffff81bb70b8: cmpq $0x57ac6e9d, (%rax)
0.00 : ffffffff81bb70bf: jne 0xffffffff81bb7bca <__schedule+0xb6a>
0.00 : ffffffff81bb70c5: movl %gs:0x7e47b87c(%rip), %eax # 0x32948 <pcpu_hot+0x8> # data-type: struct pcpu_hot +0x8 (preempt_count)
0.00 : ffffffff81bb70cc: andl $0x7fffffff, %eax
0.00 : ffffffff81bb70d1: cmpl $0x1, %eax
0.00 : ffffffff81bb70d4: jne 0xffffffff81bb79de <__schedule+0x97e>
0.00 : ffffffff81bb70da: nopl (%rax,%rax)
0.00 : ffffffff81bb70df: cmpl $0x2, 0xe86b3a(%rip) # 0xffffffff82a3dc20 <prof_on> # data-type: int +0
0.00 : ffffffff81bb70e6: movq 0x8(%rbp), %rsi
0.00 : ffffffff81bb70ea: je 0xffffffff81bb7a0b <__schedule+0x9ab>
0.00 : ffffffff81bb70f0: nopl (%rax,%rax)
0.00 : ffffffff81bb70f5: nop
...
The code is also available at 'perf/annotate-code-data-v2' branch in
git://git.kernel.org/pub/scm/linux/kernel/git/namhyung/linux-perf.git
Thanks,
Namhyung
Namhyung Kim (7):
perf annotate-data: Add annotated_data_type__get_member_name()
perf annotate: Remove unused len parameter from annotation_line__print()
perf annotate: Pass annotation_options to annotation_line__print()
perf annotate: Pass hist_entry to annotate functions
perf annotate: Factor out __hist_entry__get_data_type()
perf annotate: Implement code + data type annotation
perf annotate: Add --code-with-type option.
tools/perf/Documentation/perf-annotate.txt | 4 +
tools/perf/builtin-annotate.c | 19 +-
tools/perf/builtin-top.c | 2 +-
tools/perf/util/annotate-data.c | 34 +++
tools/perf/util/annotate-data.h | 13 +
tools/perf/util/annotate.c | 267 +++++++++++++--------
tools/perf/util/annotate.h | 8 +-
tools/perf/util/sort.c | 39 +--
8 files changed, 246 insertions(+), 140 deletions(-)
--
2.49.0.rc0.332.g42c0ae87b1-goog