perf symbol: Fail to read phdr workaround
The perf jvmti agent doesn't create program headers, in this case
fallback on section headers as happened previously.
Committer notes:
To test this, from a public post by Ian:
1) download a Java workload dacapo-9.12-MR1-bach.jar from
https://sourceforge.net/projects/dacapobench/
2) build perf such as "make -C tools/perf O=/tmp/perf NO_LIBBFD=1" it
should detect Java and create /tmp/perf/libperf-jvmti.so
3) run perf with the jvmti agent:
perf record -k 1 java -agentpath:/tmp/perf/libperf-jvmti.so -jar dacapo-9.12-MR1-bach.jar -n 10 fop
4) run perf inject:
perf inject -i perf.data -o perf-injected.data -j
5) run perf report
perf report -i perf-injected.data | grep org.apache.fop
With this patch reverted I see lots of symbols like:
0.00% java jitted-388040-4656.so [.] org.apache.fop.fo.FObj.bind(org.apache.fop.fo.PropertyList)
With the patch (
c436ad9f4a2a0926 ("perf symbol: Correct address for bss
symbols")) I see lots of:
dso__load_sym_internal: failed to find program header for symbol:
Lorg/apache/fop/fo/FObj;bind(Lorg/apache/fop/fo/PropertyList;)V
st_value: 0x40
Fixes: c436ad9f4a2a0926 ("perf symbol: Correct address for bss symbols")
Reviewed-by: Leo Yan <leo.yan@linaro.org>
Signed-off-by: Ian Rogers <irogers@google.com>
Tested-by: Leo Yan <leo.yan@linaro.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20220731164923.691193-1-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>