When new maps are cloned out of split map they are added into origin
map's group, but their groups pointer is not updated.
This could lead to a segfault, because map->groups is expected to be
always set as reported by Markus:
__map__is_kernel (map=map@entry=0x1abb7a0) at util/map.c:238
238 return __machine__kernel_map(map->groups->machine, map->type) =
(gdb) bt
#0 __map__is_kernel (map=map@entry=0x1abb7a0) at util/map.c:238
#1 0x00000000004393e4 in symbol_filter (map=map@entry=0x1abb7a0, sym=sym@entry
#2 0x00000000004fcd4d in dso__load_sym (dso=dso@entry=0x166dae0, map=map@entry
#3 0x00000000004a64e0 in dso__load (dso=0x166dae0, map=map@entry=0x1abb7a0, fi
#4 0x00000000004b941f in map__load (filter=0x4393c0 <symbol_filter>, map=<opti
#5 map__find_symbol (map=0x1abb7a0, addr=40188, filter=0x4393c0 <symbol_filter
...
Adding __map_groups__insert function to add map into groups together
with map->groups pointer update. It takes no lock as opposed to existing
map_groups__insert, as maps__fixup_overlappings(), where it is being
called, already has the necessary lock held.
Using __map_groups__insert to add new maps after map split.
Reported-by: Markus Trippelsdorf <markus@trippelsdorf.de>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Markus Trippelsdorf <markus@trippelsdorf.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20151104140811.GA32664@krava.brq.redhat.com
Fixes: cfc5acd4c8 ("perf top: Filter symbols based on __map__is_kernel(map)")
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This has a different model than the 'thread' and 'map' struct lifetimes:
there is not a definitive "don't use this DSO anymore" event, i.e. we may
get many 'struct map' holding references to the '/usr/lib64/libc-2.20.so'
DSO but then at some point some DSO may have no references but we still
don't want to straight away release its resources, because "soon" we may
get a new 'struct map' that needs it and we want to reuse its symtab or
other resources.
So we need some way to garbage collect it when crossing some memory
usage threshold, which is left for anoter patch, for now it is
sufficient to release it when calling dsos__exit(), i.e. when deleting
the whole list as part of deleting the 'struct machine' containing it,
which will leave only referenced objects being used.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/n/tip-majzgz07cm90t2tejrjy4clf@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To make it consistent with the other dso lifetime routines.
For instance:
struct dso *vdso__new(struct machine *machine, const char *short_name,
const char *long_name)
Becomes:
struct dso *machine__addnew_vdso(struct machine *machine, const
char *short_name, const char *long_name)
Because:
1) There is no 'struct vdso' for us to have vdso__ prefixed routines.
2) Because it will not really just create a new instance of 'struct
dso', it'll call dso__new() but it will also insert it into the
DSO's list/rbtree, and we have a method name for that: 'addnew',
just like we have dsos__addnew().
3) So it is really a 'struct machine' operation, it is the first
argument, etc.
This way the place where this is used gets consistent:
if (vdso) {
pgoff = 0;
- dso = vdso__dso_findnew(machine, thread);
+ dso = machine__findnew_vdso(machine, thread);
} else
dso = machine__findnew_dso(machine, filename);
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/n/tip-r3w3tvh8exm9xfz3p4tz9qbz@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
We have pointers to struct map instances in several places, like in the
hist_entry instances, so we need a way to know when we can destroy them,
otherwise we may either keep leaking them or end up referencing deleted
instances.
Start fixing it by reference counting them.
This patch puts the reference count for struct map in place, replacing
direct map__delete() calls with map__put() ones and then grabbing a
reference count when adding it to the maps struct where maps for a
struct thread are kept.
Next we'll grab reference counts when setting pointers to struct map
instances, in places like in the hist_entry code.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-wi19xczk0t2a41r1i2chuio5@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This patch fixes off-by-one errors in the management of maps.
A map is defined by start address and length as implemented by
map__new():
map__init(map, type, start, start + len, pgoff, dso);
map->start = addr;
map->end = end;
Consequently, the actual address range is [start; end[ map->end is the
first byte outside the range.
This patch fixes two bugs where upper bound checking was off-by-one.
In V2, we fix map_groups__fixup_overlappings() some more where
map->start was off-by-one as reported by Jiri.
Signed-off-by: Stephane Eranian <eranian@google.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20141006083532.GA4850@quad
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>