Fix spurious "backtraces skipped due to no file mapping" log entries
When using operf to do callgraph profiling, the following message may be
WARNING: Lost samples detected! See .../oprofile_data/samples/operf.log for details.
And in the operf.log, you may see something like:
Nr. backtraces skipped due to no file mapping: 267
A bug in the code is causing most of these "no file mapping" counts.
This patch fixes that problem.
Signed-off-by: Maynard Johnson <email@example.com>