[PATCHSET/RFC 0/9] perf tools: Support out-of-tree modules

[Namhyung Kim]

Hello,

Currently perf loads modules only in the canonical directory
(/lib/modules/`uname -r`/).  But in some situation users want to use
local or out-of-tree modules which are not placed in the directory.

One example is developing kernel in a qemu environment.  In this case,
guest doesn't see vmlinux or modules but one can load a module in some
directory which was copied separately.  During the development, the
module can be unloaded, fixed and reloaded more than once.

I notice that perf uses symbols in /proc/kallsyms (and /proc/kcore)
and it sometimes shows different result with a same data file.  This
was due to a same module being loaded at a different address or a
reworked module being loaded at a same address.

I think it needs to use build-id cache if possible.  To do that we
need to add an option to search modules and to save them in the
build-id cache automatically.

The code is available on 'perf/kmod-dir-v1' branch at

  git://git.kernel.org/pub/scm/linux/kernel/git/namhyung/linux-perf.git

Thanks,
Namhyung


Namhyung Kim (9):
  perf symbols: Use absolute address to fixup map address
  perf tools: Remove duplicate code
  perf symbols: Discard symbols in kallsyms for loaded modules
  perf symbols: Load kernel module symbols ASAP
  perf symbols: Fixup the end address of kernel map properly
  perf symbols: Use already loaded module dso when loading kcore
  perf tools: Add symbol_conf.use_kcore
  perf record: Not use kcore by default
  perf record: Add --module-dir option

 tools/perf/Documentation/perf-record.txt |  6 ++++
 tools/perf/builtin-record.c              |  7 ++++
 tools/perf/perf-with-kcore.sh            |  1 +
 tools/perf/util/machine.c                | 33 ++++++++---------
 tools/perf/util/map.c                    |  4 +--
 tools/perf/util/symbol.c                 | 61 +++++++++++++++++---------------
 tools/perf/util/symbol.h                 |  6 ++--
 7 files changed, 69 insertions(+), 49 deletions(-)

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2.13.1