Hi,
Here is the 2nd version of remote cross-arch probe support on perf-probe.
V1 is here:
https://lkml.org/lkml/2016/8/24/29
Currently perf-probe doesn't supoort cross/remote target. This means
we have to cross-build the perf-tools including libraries (elfutils,
libelf etc.), and to prepare vmlinux with debuginfo which can be
accessed from the target machine.
This requires too much resource for a small embededd device.
If we can analyze the debuginfo by perf-probe on host machine,
we do not need to cross-build perf-tools, nor copy vmlinux on the
device. :)
For that purpose, this series adds --definition(-D) command for
perf-probe, which shows trace event definition instead of adding
it in running kernel, according to Arnaldo's comment.
Using -D with --vmlinux(or -k)=OFFLINE-VMLINUX, perf-probe reads
the vmlinux architecture and show definition with correct
dwarf-registers.
perf probe -k <cross-vmlinux> -D <probe-point> <arguments>
Here is an example:
-----
$ perf probe --vmlinux=./vmlinux-arm --definition 'do_sys_open $params'
p:probe/do_sys_open do_sys_open+0 dfd=%r5:s32 filename=%r1:u32 flags=%r6:s32
mode=%r3:u16
-----
Here, we can get probe/do_sys_open event by "copy & paste" the
definition to target-machine's debugfs/tracing/kprobe_events.
Note that it shows definition with direct symbol name instead of
_text+offset. It is treated as an offline module.
Thanks,
---
Masami Hiramatsu (3):
perf-probe: Show trace event definition
perf-probe: Ignore vmlinux buildid if offline kernel is given
perf-probe: Support probing on offline cross-arch binary
tools/perf/Documentation/perf-probe.txt | 9 +++
tools/perf/arch/arm/include/dwarf-regs-table.h | 9 +++
tools/perf/arch/arm64/include/dwarf-regs-table.h | 13 +++++
tools/perf/arch/powerpc/include/dwarf-regs-table.h | 27 ++++++++++
tools/perf/arch/s390/include/dwarf-regs-table.h | 8 +++
tools/perf/arch/sh/include/dwarf-regs-table.h | 25 +++++++++
tools/perf/arch/sparc/include/dwarf-regs-table.h | 18 +++++++
tools/perf/arch/x86/include/dwarf-regs-table.h | 14 +++++
tools/perf/arch/xtensa/include/dwarf-regs-table.h | 8 +++
tools/perf/builtin-probe.c | 34 ++++++++++--
tools/perf/util/Build | 1
tools/perf/util/dwarf-regs.c | 55 ++++++++++++++++++++
tools/perf/util/include/dwarf-regs.h | 6 ++
tools/perf/util/probe-event.c | 50 ++++++++++++++++++
tools/perf/util/probe-event.h | 1
tools/perf/util/probe-finder.c | 27 ++++++----
tools/perf/util/probe-finder.h | 1
tools/perf/util/symbol-elf.c | 2 -
18 files changed, 289 insertions(+), 19 deletions(-)
create mode 100644 tools/perf/arch/arm/include/dwarf-regs-table.h
create mode 100644 tools/perf/arch/arm64/include/dwarf-regs-table.h
create mode 100644 tools/perf/arch/powerpc/include/dwarf-regs-table.h
create mode 100644 tools/perf/arch/s390/include/dwarf-regs-table.h
create mode 100644 tools/perf/arch/sh/include/dwarf-regs-table.h
create mode 100644 tools/perf/arch/sparc/include/dwarf-regs-table.h
create mode 100644 tools/perf/arch/x86/include/dwarf-regs-table.h
create mode 100644 tools/perf/arch/xtensa/include/dwarf-regs-table.h
create mode 100644 tools/perf/util/dwarf-regs.c
--
Masami Hiramatsu (Linaro Ltd.) <[email protected]>
