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perf machine: Fix refcount usage when processing PERF_RECORD_KSYMBOL
ASan reported a memory leak of BPF-related ksymbols map and dso. The leak is caused by refount never reaching 0, due to missing __put calls in the function machine__process_ksymbol_register. Once the dso is inserted in the map, dso__put() should be called (map__new2() increases the refcount to 2). The same thing applies for the map when it's inserted into maps (maps__insert() increases the refcount to 2). $ sudo ./perf record -- sleep 5 [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.025 MB perf.data (8 samples) ] ================================================================= ==297735==ERROR: LeakSanitizer: detected memory leaks Direct leak of 6992 byte(s) in 19 object(s) allocated from: #0 0x4f43c7 in calloc (/home/user/linux/tools/perf/perf+0x4f43c7) #1 0x8e4e53 in map__new2 /home/user/linux/tools/perf/util/map.c:216:20 #2 0x8cf68c in machine__process_ksymbol_register /home/user/linux/tools/perf/util/machine.c:778:10 [...] Indirect leak of 8702 byte(s) in 19 object(s) allocated from: #0 0x4f43c7 in calloc (/home/user/linux/tools/perf/perf+0x4f43c7) #1 0x8728d7 in dso__new_id /home/user/linux/tools/perf/util/dso.c:1256:20 #2 0x872015 in dso__new /home/user/linux/tools/perf/util/dso.c:1295:9 #3 0x8cf623 in machine__process_ksymbol_register /home/user/linux/tools/perf/util/machine.c:774:21 [...] Indirect leak of 1520 byte(s) in 19 object(s) allocated from: #0 0x4f43c7 in calloc (/home/user/linux/tools/perf/perf+0x4f43c7) #1 0x87b3da in symbol__new /home/user/linux/tools/perf/util/symbol.c:269:23 #2 0x888954 in map__process_kallsym_symbol /home/user/linux/tools/perf/util/symbol.c:710:8 [...] Indirect leak of 1406 byte(s) in 19 object(s) allocated from: #0 0x4f43c7 in calloc (/home/user/linux/tools/perf/perf+0x4f43c7) #1 0x87b3da in symbol__new /home/user/linux/tools/perf/util/symbol.c:269:23 #2 0x8cfbd8 in machine__process_ksymbol_register /home/user/linux/tools/perf/util/machine.c:803:8 [...] Signed-off-by: Riccardo Mancini <rickyman7@gmail.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Jiapeng Chong <jiapeng.chong@linux.alibaba.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Tommi Rantala <tommi.t.rantala@nokia.com> Link: http://lore.kernel.org/lkml/20210612173751.188582-1-rickyman7@gmail.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>