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perf symbols: Fix kernel maps for kcore and eBPF

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commit 0affd0e5262b6d40f5f63466d88933e99698e240 upstream.

Adjust 'map->pgoff' also when moving a map's start address.

Example with v5.4.34 based kernel:

  Before:

    $ sudo tools/perf/perf record -a --kcore -e intel_pt//k sleep 1
    [ perf record: Woken up 1 times to write data ]
    [ perf record: Captured and wrote 1.958 MB perf.data ]
    $ sudo tools/perf/perf script --itrace=e >/dev/null
    Warning:
    961 instruction trace errors

  After:

    $ sudo tools/perf/perf script --itrace=e >/dev/null
    $

Committer testing:

  # uname -a
  Linux seventh 5.6.10-100.fc30.x86_64 #1 SMP Mon May 4 15:36:44 UTC 2020 x86_64 x86_64 x86_64 GNU/Linux
  #

Before:

  # perf record -a --kcore -e intel_pt//k sleep 1
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.923 MB perf.data ]
  # perf script --itrace=e >/dev/null
  Warning:
  295 instruction trace errors
  #

After:

  # perf record -a --kcore -e intel_pt//k sleep 1
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.919 MB perf.data ]
  # perf script --itrace=e >/dev/null
  #

Fixes: fb5a88d4131a ("perf tools: Preserve eBPF maps when loading kcore")
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: stable@vger.kernel.org
Link: http://lore.kernel.org/lkml/20200602112505.1406-1-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Adrian Hunter 2020-06-02 14:25:05 +03:00 committed by Greg Kroah-Hartman
parent 807cc607f1
commit 8e38ea68da
1 changed files with 2 additions and 0 deletions
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2
tools/perf/util/symbol.c
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@ -1221,6 +1221,7 @@ int map_groups__merge_in(struct map_groups *kmaps, struct map *new_map)
m->end = old_map->start;
list_add_tail(&m->node, &merged);
new_map->pgoff += old_map->end - new_map->start;
new_map->start = old_map->end;
}
} else {
@ -1241,6 +1242,7 @@ int map_groups__merge_in(struct map_groups *kmaps, struct map *new_map)
* |new......| -> |new...|
* |old....| -> |old....|
*/
new_map->pgoff += old_map->end - new_map->start;
new_map->start = old_map->end;
}
}