From e96e4078e9a5ea150b3ad9a296440a7976439e4a Mon Sep 17 00:00:00 2001
From: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Date: Wed, 18 Nov 2015 15:40:22 +0900
Subject: [PATCH] perf machine: Fix machine__destroy_kernel_maps to drop
vmlinux_maps references
Fix machine__destroy_kernel_maps() to drop vmlinux_maps references
before filling it with NULL.
Refcnt debugger shows
==== [1] ====
Unreclaimed map: 0x36b1070
Refcount +1 => 1 at
./perf(map__new2+0xb5) [0x4bdec5]
./perf(machine__create_kernel_maps+0x72) [0x4bb152]
./perf(machine__new_host+0xfa) [0x4bb41a]
./perf(init_probe_symbol_maps+0x93) [0x5062d3]
./perf() [0x455ffa]
./perf(cmd_probe+0x6c) [0x4566bc]
./perf() [0x47abc5]
./perf(main+0x610) [0x421f90]
/lib64/libc.so.6(__libc_start_main+0xf5) [0x7f1fc9fc4af5]
./perf() [0x4220a9]
Refcount +1 => 2 at
./perf(maps__insert+0x9a) [0x4bfd6a]
./perf(machine__create_kernel_maps+0xc3) [0x4bb1a3]
./perf(machine__new_host+0xfa) [0x4bb41a]
./perf(init_probe_symbol_maps+0x93) [0x5062d3]
./perf() [0x455ffa]
./perf(cmd_probe+0x6c) [0x4566bc]
./perf() [0x47abc5]
./perf(main+0x610) [0x421f90]
/lib64/libc.so.6(__libc_start_main+0xf5) [0x7f1fc9fc4af5]
./perf() [0x4220a9]
Refcount -1 => 1 at
./perf(map_groups__exit+0x94) [0x4bea74]
./perf(machine__delete+0x3d) [0x4b91fd]
./perf(exit_probe_symbol_maps+0x28) [0x506378]
./perf() [0x45628a]
./perf(cmd_probe+0x6c) [0x4566bc]
./perf() [0x47abc5]
./perf(main+0x610) [0x421f90]
/lib64/libc.so.6(__libc_start_main+0xf5) [0x7f1fc9fc4af5]
./perf() [0x4220a9]
map__new2() returns map with refcnt = 1, and also map_groups__insert
gets it again in__machine__create_kernel_maps().
machine__destroy_kernel_maps() calls map_groups__remove() to
decrement the refcnt, but before decrement it again (corresponding
to map__new2), it makes vmlinux_maps[type] = NULL. And this may
cause a refcnt leak.
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20151118064022.30709.3897.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
tools/perf/util/machine.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c
index 0487d7795f13..e9e09bee221c 100644
--- a/tools/perf/util/machine.c
+++ b/tools/perf/util/machine.c
@@ -790,6 +790,7 @@ void machine__destroy_kernel_maps(struct machine *machine)
kmap->ref_reloc_sym = NULL;
}
+ map__put(machine->vmlinux_maps[type]);
machine->vmlinux_maps[type] = NULL;
}
}
--
GitLab