On Mon, 23 Mar 2020 00:54:01 +0430 ahmadkhorrami <ahmadkhorrami@xxxxxxxx> wrote: > Hi, > 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. Could you show some examples of the backtraces you mention? > > 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. -- Steve
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