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Commit 22a66551 authored by Yang Jihong's avatar Yang Jihong Committed by Arnaldo Carvalho de Melo
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perf probe: Fix add event failure when running 32-bit perf in a 64-bit kernel



The "address" member of "struct probe_trace_point" uses long data type.
If kernel is 64-bit and perf program is 32-bit, size of "address"
variable is 32 bits.

As a result, upper 32 bits of address read from kernel are truncated, an
error occurs during address comparison in kprobe_warn_out_range().

Before:

  # perf probe -a schedule
  schedule is out of .text, skip it.
    Error: Failed to add events.

Solution:
  Change data type of "address" variable to u64 and change corresponding
address printing and value assignment.

After:

  # perf.new.new probe -a schedule
  Added new event:
    probe:schedule       (on schedule)

  You can now use it in all perf tools, such as:

          perf record -e probe:schedule -aR sleep 1

  # perf probe -l
    probe:schedule       (on schedule@kernel/sched/core.c)
  # perf record -e probe:schedule -aR sleep 1
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.156 MB perf.data (1366 samples) ]
  # perf report --stdio
  # To display the perf.data header info, please use --header/--header-only options.
  #
  #
  # Total Lost Samples: 0
  #
  # Samples: 1K of event 'probe:schedule'
  # Event count (approx.): 1366
  #
  # Overhead  Command          Shared Object      Symbol
  # ........  ...............  .................  ............
  #
       6.22%  migration/0      [kernel.kallsyms]  [k] schedule
       6.22%  migration/1      [kernel.kallsyms]  [k] schedule
       6.22%  migration/2      [kernel.kallsyms]  [k] schedule
       6.22%  migration/3      [kernel.kallsyms]  [k] schedule
       6.15%  migration/10     [kernel.kallsyms]  [k] schedule
       6.15%  migration/11     [kernel.kallsyms]  [k] schedule
       6.15%  migration/12     [kernel.kallsyms]  [k] schedule
       6.15%  migration/13     [kernel.kallsyms]  [k] schedule
       6.15%  migration/14     [kernel.kallsyms]  [k] schedule
       6.15%  migration/15     [kernel.kallsyms]  [k] schedule
       6.15%  migration/4      [kernel.kallsyms]  [k] schedule
       6.15%  migration/5      [kernel.kallsyms]  [k] schedule
       6.15%  migration/6      [kernel.kallsyms]  [k] schedule
       6.15%  migration/7      [kernel.kallsyms]  [k] schedule
       6.15%  migration/8      [kernel.kallsyms]  [k] schedule
       6.15%  migration/9      [kernel.kallsyms]  [k] schedule
       0.22%  rcu_sched        [kernel.kallsyms]  [k] schedule
  ...
  #
  # (Cannot load tips.txt file, please install perf!)
  #

Signed-off-by: default avatarYang Jihong <yangjihong1@huawei.com>
Acked-by: default avatarMasami Hiramatsu <mhiramat@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jianlin Lv <jianlin.lv@arm.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Li Huafei <lihuafei1@huawei.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Link: http://lore.kernel.org/lkml/20210715063723.11926-1-yangjihong1@huawei.com


Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
parent d4b3eedc
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