Jolsa Docs Annotations

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TODO: description & examples

The perf annotations is based on objdump tool from binutils package.


Annotations are based on debuginfo, which on most (Fedora) distributions come in separated *-debuginfo packages. Unfortunately objdump does not connect binaries with its debuginfo counterparts.

The result is that for binaries with separated debuginfo you'll not see annotations in perf.


There's a following workaround, that merges debuginfo back to the binary. Such binary will display proper annotations in perf.

The binary we want to annotate properly is ls.

  • find out the debuginfo holder:
$ rpm -ql coreutils-debuginfo | grep ls.debug
  • OPTIONAL if your distribution uses prelink, you need to undo it:
$ cp /bin/ls .
$ prelink -u ls
  • create the ls-di binary with debuginfo merged:
$ eu-unstrip -o ls-di ./ls /usr/lib/debug/usr/bin/ls.debug
$ file ls-di
ls-di: ELF 64-bit LSB executable, x86-64, version 1 (SYSV) [SNIP] not stripped
  • clean the build-id cache, since the ls share same build-id with ls-di:
$ perf buildid-cache -r ls
# or more efectively:
$ rm -rf ~/.debug/
  • enjoy your annotations via:
$ perf record ./ls-di [SNIP]
$ perf annotate [FUNC]
$ perf report
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