tools/perf/util/Build | 1 + tools/perf/util/annotate.c | 1711 ++--------------------------------- tools/perf/util/annotate.h | 59 +- tools/perf/util/disasm.c | 1739 ++++++++++++++++++++++++++++++++++++ tools/perf/util/disasm.h | 112 +++ 5 files changed, 1914 insertions(+), 1708 deletions(-) create mode 100644 tools/perf/util/disasm.c create mode 100644 tools/perf/util/disasm.h
Hello, As we've added libcapstone support, it's natural to use it for perf annotate as well. This change added the capstone support on x86 first. Other archs can be added later (by someone who can verify it doesn't break things). For now it tries to use capstone (if available) before objdump. But it doesn't support source file and line number info. So users should use the objdump (by passing --objdump=PATH option) if they need them. For example, this command line will keep the existing behavior (i.e. using objdump). # not to use capstone for disassembly $ perf annotate --objdump=objdump The capstone uses LLVM objdump style output which is slightly different than the GNU objdump. But it should not have differences besides that. I've verified the result of data type profiling and it produced the same output but gave me ~3x speedups. Thanks, Namhyung Cc: Changbin Du <changbin.du@huawei.com> Namhyung Kim (4): perf annotate: Use ins__is_xxx() if possible perf annotate: Add and use ins__is_nop() perf annotate: Split out util/disasm.c perf annotate: Use libcapstone to disassemble tools/perf/util/Build | 1 + tools/perf/util/annotate.c | 1711 ++--------------------------------- tools/perf/util/annotate.h | 59 +- tools/perf/util/disasm.c | 1739 ++++++++++++++++++++++++++++++++++++ tools/perf/util/disasm.h | 112 +++ 5 files changed, 1914 insertions(+), 1708 deletions(-) create mode 100644 tools/perf/util/disasm.c create mode 100644 tools/perf/util/disasm.h -- 2.44.0.478.gd926399ef9-goog
On Thu, Mar 28, 2024 at 04:20:05PM -0700, Namhyung Kim wrote: > Hello, > > As we've added libcapstone support, it's natural to use it for perf annotate > as well. This change added the capstone support on x86 first. Other archs > can be added later (by someone who can verify it doesn't break things). > > For now it tries to use capstone (if available) before objdump. But it > doesn't support source file and line number info. So users should use the > objdump (by passing --objdump=PATH option) if they need them. For example, > this command line will keep the existing behavior (i.e. using objdump). > > # not to use capstone for disassembly > $ perf annotate --objdump=objdump > > The capstone uses LLVM objdump style output which is slightly different than > the GNU objdump. But it should not have differences besides that. I've > verified the result of data type profiling and it produced the same output > but gave me ~3x speedups. Excellent news, I'll try and test all this soon! - Arnaldo
On Thu, Mar 28, 2024 at 4:20 PM Namhyung Kim <namhyung@kernel.org> wrote: > > Hello, > > As we've added libcapstone support, it's natural to use it for perf annotate > as well. This change added the capstone support on x86 first. Other archs > can be added later (by someone who can verify it doesn't break things). > > For now it tries to use capstone (if available) before objdump. But it > doesn't support source file and line number info. So users should use the > objdump (by passing --objdump=PATH option) if they need them. For example, > this command line will keep the existing behavior (i.e. using objdump). > > # not to use capstone for disassembly > $ perf annotate --objdump=objdump > > The capstone uses LLVM objdump style output which is slightly different than > the GNU objdump. But it should not have differences besides that. I've > verified the result of data type profiling and it produced the same output > but gave me ~3x speedups. > > Thanks, > Namhyung I wanted to see what -fsanitize=address would think of libcaptstone and no issues, so: Tested-by: Ian Rogers <irogers@google.com> Some thoughts: - it may be worth adding to the commit message in "perf annotate: Split out util/disasm.c" that there's no functional change, - we lack perf annotate testing, - it seems capstone should be opt-out rather than opt-in as a library dependency (given the performance delta and the objdump interactions are at best messy), - if libcapstone could solve our addr2line issues too this would be great :-). Thanks, Ian > Cc: Changbin Du <changbin.du@huawei.com> > > > Namhyung Kim (4): > perf annotate: Use ins__is_xxx() if possible > perf annotate: Add and use ins__is_nop() > perf annotate: Split out util/disasm.c > perf annotate: Use libcapstone to disassemble > > tools/perf/util/Build | 1 + > tools/perf/util/annotate.c | 1711 ++--------------------------------- > tools/perf/util/annotate.h | 59 +- > tools/perf/util/disasm.c | 1739 ++++++++++++++++++++++++++++++++++++ > tools/perf/util/disasm.h | 112 +++ > 5 files changed, 1914 insertions(+), 1708 deletions(-) > create mode 100644 tools/perf/util/disasm.c > create mode 100644 tools/perf/util/disasm.h > > -- > 2.44.0.478.gd926399ef9-goog >
Hi Ian, On Fri, Mar 29, 2024 at 9:33 AM Ian Rogers <irogers@google.com> wrote: > > On Thu, Mar 28, 2024 at 4:20 PM Namhyung Kim <namhyung@kernel.org> wrote: > > > > Hello, > > > > As we've added libcapstone support, it's natural to use it for perf annotate > > as well. This change added the capstone support on x86 first. Other archs > > can be added later (by someone who can verify it doesn't break things). > > > > For now it tries to use capstone (if available) before objdump. But it > > doesn't support source file and line number info. So users should use the > > objdump (by passing --objdump=PATH option) if they need them. For example, > > this command line will keep the existing behavior (i.e. using objdump). > > > > # not to use capstone for disassembly > > $ perf annotate --objdump=objdump > > > > The capstone uses LLVM objdump style output which is slightly different than > > the GNU objdump. But it should not have differences besides that. I've > > verified the result of data type profiling and it produced the same output > > but gave me ~3x speedups. > > > > Thanks, > > Namhyung > > I wanted to see what -fsanitize=address would think of libcaptstone > and no issues, so: > > Tested-by: Ian Rogers <irogers@google.com> Thanks for checking it! > > Some thoughts: > - it may be worth adding to the commit message in "perf annotate: > Split out util/disasm.c" that there's no functional change, > - we lack perf annotate testing, > - it seems capstone should be opt-out rather than opt-in as a library > dependency (given the performance delta and the objdump interactions > are at best messy), > - if libcapstone could solve our addr2line issues too this would be great :-). I think addr2line should be handled using libdw. I'll take a look. Thanks, Namhyung
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