perf report: Fix a wrong offset issue when using /proc/kcore
When a valid vmlinux is not found, 'perf report' falls back to look at /proc/kcore. In this case, it will report the impossible large offset. For example: # perf record -b -e cycles:k find /etc/ > /dev/null # perf report --stdio --branch-history 22.77% _vm_normal_page+18446603336221188162 | ---page_remove_rmap +18446603336221188324 page_remove_rmap +18446603336221188487 (cycles:5) unlock_page_memcg +18446603336221188096 page_remove_rmap +18446603336221188327 (cycles:1) The issue is the value which is passed to parameter 'addr' in __get_srcline() is the objdump address. It's not correct if we calculate the offset by using 'addr - sym->start'. This patch creates a new parameter 'ip' in __get_srcline(). It is not converted to objdump address. With this patch, the perf report output is: 22.77% _vm_normal_page+66 | ---page_remove_rmap +228 page_remove_rmap +391 (cycles:5) unlock_page_memcg +0 page_remove_rmap +231 (cycles:1) page_remove_rmap +236 Committer testing: Make sure you get any valid vmlinux out of the way, using '-v' on the 'perf report' case and deleting it from places where perf searches them, like your kernel build dir and the build-id cache, in ~/.debug/. Reported-by: NArnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: NJin Yao <yao.jin@linux.intel.com> Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kan Liang <kan.liang@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1514564812-17344-1-git-send-email-yao.jin@linux.intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
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