Wrong Perf Backtraces

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I used "Perf" to extract call graphs in an evince benchmark. The command used is as follows: sudo perf record -d --call-graph dwarf -c 10000 e mem_load_uops_retired.l3_miss:uppp /opt/evince-3.28.4/bin/evince

I extracted the backtraces using "perf script" and found out that there are many corrupted backtrace instances. Some contained repeated function calls, for example two consecutive gmallocn()s exactly at the same offsets. There are also some backtraces where the callers and callees do not match.

Note that that mappings are correct. In other words, each single line of the reported backtraces is correct (i.e., addresses match with functions). But is seems that there are some function calls in the middle, which are missed by "Perf". Strangely, in all runs (and also with different sampling frequencies) the problem occurs exactly at the same place.

I am really confused and looking forward to any help. I can also send backtraces if needed.

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