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Subject[PATCH perf/core 05/13] perf: Fix machine__findnew_module_map to put registered map
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Fix machine object to put the map object which is already
insterted to machine->kmaps.

refcnt debugger shows what happened:
----
==== [2] ====
Unreclaimed map: 0x346f750
Refcount +1 => 1 at
./perf(map__new2+0xb5) [0x4bdea5]
./perf() [0x4b8aaf]
./perf(modules__parse+0xfc) [0x4a9cbc]
./perf() [0x4b83c0]
./perf(machine__create_kernel_maps+0x148) [0x4bb208]
./perf(machine__new_host+0xfa) [0x4bb3fa]
./perf(init_probe_symbol_maps+0x93) [0x5062b3]
./perf() [0x455ffa]
./perf(cmd_probe+0x6c) [0x4566bc]
./perf() [0x47abc5]
./perf(main+0x610) [0x421f90]
/lib64/libc.so.6(__libc_start_main+0xf5) [0x7f5373899af5]
./perf() [0x4220a9]
Refcount +1 => 2 at
./perf(maps__insert+0x9a) [0x4bfd4a]
./perf() [0x4b8acb]
./perf(modules__parse+0xfc) [0x4a9cbc]
./perf() [0x4b83c0]
./perf(machine__create_kernel_maps+0x148) [0x4bb208]
./perf(machine__new_host+0xfa) [0x4bb3fa]
./perf(init_probe_symbol_maps+0x93) [0x5062b3]
./perf() [0x455ffa]
./perf(cmd_probe+0x6c) [0x4566bc]
./perf() [0x47abc5]
./perf(main+0x610) [0x421f90]
/lib64/libc.so.6(__libc_start_main+0xf5) [0x7f5373899af5]
./perf() [0x4220a9]
Refcount -1 => 1 at
./perf(map_groups__exit+0x94) [0x4bea54]
./perf(machine__delete+0x3d) [0x4b91ed]
./perf(exit_probe_symbol_maps+0x28) [0x506358]
./perf() [0x45628a]
./perf(cmd_probe+0x6c) [0x4566bc]
./perf() [0x47abc5]
./perf(main+0x610) [0x421f90]
/lib64/libc.so.6(__libc_start_main+0xf5) [0x7f5373899af5]
./perf() [0x4220a9]
----
This pattern clearly shows that the refcnt of the map is acquired
twice ny map__new2 and maps__insert but released once at map_groups_exit.
Since maps__insert already got the dso, we have to put it right
after that which corresponding to the map__new2.

These are happened in machine__findnew_module_map, as below.
----
# eu-addr2line -e ./perf -f 0x4b8aaf
machine__findnew_module_map inlined at util/machine.c:1046
in machine__create_module
util/machine.c:582
# eu-addr2line -e ./perf -f 0x4b8acb
map_groups__insert inlined at util/machine.c:585
in machine__create_module
util/map.h:208
----
(note that both are at util/machine.c:58X which is
machine__findnew_module_map)
So, this patch fixes machine__findnew_module_map to put the map
right after map_groups__insert.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
---
tools/perf/util/machine.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c
index 5ef90be..5ca4064 100644
--- a/tools/perf/util/machine.c
+++ b/tools/perf/util/machine.c
@@ -584,6 +584,8 @@ struct map *machine__findnew_module_map(struct machine *machine, u64 start,

map_groups__insert(&machine->kmaps, map);

+ /* Put the map here because map_groups__insert alread got it */
+ map__put(map);
out:
free(m.name);
return map;


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