linux-stable.git/tools/perf/util/map.c, branch linux-4.3.y

perf tools: Initialize reference counts in map__clone()

2015-08-21T15:39:30+00:00

Map clone was written before we introduced reference counts for
maps and dsos, so all that was needed was just a copy and then we
would insert it into the new map_groups instance.

Fix it by, after copying, initializing the map->refcnt, grabbing
a struct dso refcount and resetting pointers that may be used
to determine if a map, when deleted, is in a rb_tree.

Cc: Adrian Hunter 
Cc: Borislav Petkov 
Cc: David Ahern 
Cc: Frederic Weisbecker 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Cc: Stephane Eranian 
Link: http://lkml.kernel.org/n/tip-pd4mr80o5b9gvk50iineacec@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf symbols: Introduce map__is_(kernel,kmodule)()

2015-07-23T14:28:36+00:00

To, with members we already have, check if a kernel level map is for the
kernel proper or for a module.

Acked-by: David Ahern 
Cc: Adrian Hunter 
Cc: Borislav Petkov 
Cc: Frederic Weisbecker 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Cc: Stephane Eranian 
Link: http://lkml.kernel.org/n/tip-m5ic7h0z2crmtj7vi1a1rj3b@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Replace map->referenced & maps->removed_maps with map->refcnt

2015-06-16T13:34:38+00:00

Use just reference counts, so that when no more hist_entry instances
references a map and the thread instance goes away by processing a
PERF_RECORD_EXIT, we can delete the maps.

Cc: Adrian Hunter 
Cc: Borislav Petkov 
Cc: David Ahern 
Cc: Don Zickus 
Cc: Frederic Weisbecker 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Cc: Stephane Eranian 
Link: http://lkml.kernel.org/n/tip-oym7lfhcc7ss6xpz44h7nbxs@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Reference count struct dso

2015-06-08T13:31:40+00:00

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 
Cc: David Ahern 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Link: http://lkml.kernel.org/n/tip-majzgz07cm90t2tejrjy4clf@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf machine: Fix up vdso methods names

2015-05-29T15:43:44+00:00

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 
Cc: David Ahern 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Link: http://lkml.kernel.org/n/tip-r3w3tvh8exm9xfz3p4tz9qbz@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf machine: Introduce machine__findnew_dso() method

2015-05-29T15:43:44+00:00

Similar to machine__findnew_thread(), also prepping for refcounting and
locking, this time for struct dso instances.

Cc: Adrian Hunter 
Cc: David Ahern 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Link: http://lkml.kernel.org/n/tip-fv3tshv5o1413coh147lszjc@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf machine: No need to have two DSOs lists

2015-05-29T15:43:43+00:00

We can, given a DSO, figure out if it is a kernel, a kernel module or
a userlevel DSO, so stop having to process two lists in several
functions.

If searching becomes an issue at some point, we can have them in a
rbtree, etc.

Cc: Adrian Hunter 
Cc: Borislav Petkov 
Cc: David Ahern 
Cc: Don Zickus 
Cc: Frederic Weisbecker 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Cc: Stephane Eranian 
Link: http://lkml.kernel.org/n/tip-s4yb0onpdywu6dj2xl9lxi4t@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Reference count struct map

2015-05-27T23:27:30+00:00

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 
Cc: Borislav Petkov 
Cc: David Ahern 
Cc: Don Zickus 
Cc: Frederic Weisbecker 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Cc: Stephane Eranian 
Link: http://lkml.kernel.org/n/tip-wi19xczk0t2a41r1i2chuio5@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Check if a map is still in use when deleting it

2015-05-27T23:27:16+00:00

I.e. match RB_CLEAR_NODE() with RB_EMPTY_NODE(), to check that it isn't
in a rb tree at the time of its deletion.

Cc: Adrian Hunter 
Cc: Borislav Petkov 
Cc: David Ahern 
Cc: Don Zickus 
Cc: Frederic Weisbecker 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Cc: Stephane Eranian 
Link: http://lkml.kernel.org/n/tip-vumvhird765id11zbx00d2r8@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Protect accesses the map rbtrees with a rw lock

2015-05-27T23:25:16+00:00

To allow concurrent access, next step: refcount struct map instances, so
that we can ditch maps->removed_maps and stop leaking threads, maps,
then struct DSO needs the same treatment.

Cc: Adrian Hunter 
Cc: Borislav Petkov 
Cc: David Ahern 
Cc: Don Zickus 
Cc: Frederic Weisbecker 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Cc: Stephane Eranian 
Link: http://lkml.kernel.org/n/tip-o45w2w5dzrza38nzqxnqzhyf@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo