| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-ID: <CAP-5=fWHDZOCgmm7x+Lcgh6Gx+5orSGaDs7XmeL6hxTL8Kwx5A@mail.gmail.com>
Date: Mon, 20 Mar 2023 10:00:11 -0700
From: Ian Rogers <irogers@...gle.com>
To: Adrian Hunter <adrian.hunter@...el.com>
Cc: Peter Zijlstra <peterz@...radead.org>,
Ingo Molnar <mingo@...hat.com>,
Arnaldo Carvalho de Melo <acme@...nel.org>,
Mark Rutland <mark.rutland@....com>,
Alexander Shishkin <alexander.shishkin@...ux.intel.com>,
Jiri Olsa <jolsa@...nel.org>,
Namhyung Kim <namhyung@...nel.org>,
Thomas Gleixner <tglx@...utronix.de>,
Darren Hart <dvhart@...radead.org>,
Davidlohr Bueso <dave@...olabs.net>,
André Almeida <andrealmeid@...labora.com>,
James Clark <james.clark@....com>,
John Garry <john.g.garry@...cle.com>,
Riccardo Mancini <rickyman7@...il.com>,
Yury Norov <yury.norov@...il.com>,
Andy Shevchenko <andriy.shevchenko@...ux.intel.com>,
Andrew Morton <akpm@...ux-foundation.org>,
Leo Yan <leo.yan@...aro.org>, Andi Kleen <ak@...ux.intel.com>,
Thomas Richter <tmricht@...ux.ibm.com>,
Kan Liang <kan.liang@...ux.intel.com>,
Madhavan Srinivasan <maddy@...ux.ibm.com>,
Shunsuke Nakamura <nakamura.shun@...itsu.com>,
Song Liu <song@...nel.org>,
Masami Hiramatsu <mhiramat@...nel.org>,
Steven Rostedt <rostedt@...dmis.org>,
Miaoqian Lin <linmq006@...il.com>,
Stephen Brennan <stephen.s.brennan@...cle.com>,
Kajol Jain <kjain@...ux.ibm.com>,
Alexey Bayduraev <alexey.v.bayduraev@...ux.intel.com>,
German Gomez <german.gomez@....com>,
linux-perf-users@...r.kernel.org, linux-kernel@...r.kernel.org,
Eric Dumazet <edumazet@...gle.com>,
Dmitry Vyukov <dvyukov@...gle.com>,
Hao Luo <haoluo@...gle.com>,
Stephane Eranian <eranian@...gle.com>
Subject: Re: [PATCH v4 17/22] perf map: Changes to reference counting
On Mon, Mar 20, 2023 at 4:19 AM Adrian Hunter <adrian.hunter@...el.com> wrote:
>
> On 20/03/23 05:38, Ian Rogers wrote:
> > When a pointer to a map exists do a get, when that pointer is
> > overwritten or freed, put the map. This avoids issues with gets and
> > puts being inconsistently used causing, use after puts, etc. For
> > example, the map in struct addr_location is changed to hold a
> > reference count.
>
> I am not sure I understand the reason for that. A thread's address
> mappings are inherently transitory with respect to perf (MMAP) event
> processing. Holding on to a reference to a thread's map is not a
> valid thing to do if more perf events can be processed in the meantime.
> Reference counting seems to hide the problem in that case, since
> the solution is: don't keep the reference.
Agreed. I think the code is complex enough that we just need to do
proper reference counting so that we don't get use after frees, etc.
I've tried to fix things here by only following what leak tracker is
telling me, rather than fully wholesale getting/putting.
> > Reference count checking and address sanitizer were
> > used to identify issues.
> >
> > Signed-off-by: Ian Rogers <irogers@...gle.com>
> > ---
> > tools/perf/tests/code-reading.c | 1 +
> > tools/perf/tests/hists_cumulate.c | 10 ++++
> > tools/perf/tests/hists_filter.c | 10 ++++
> > tools/perf/tests/hists_link.c | 18 +++++-
> > tools/perf/tests/hists_output.c | 10 ++++
> > tools/perf/tests/mmap-thread-lookup.c | 1 +
> > tools/perf/util/callchain.c | 9 +--
> > tools/perf/util/event.c | 8 ++-
> > tools/perf/util/hist.c | 10 ++--
> > tools/perf/util/machine.c | 79 ++++++++++++++++-----------
> > tools/perf/util/map.c | 2 +-
> > 11 files changed, 114 insertions(+), 44 deletions(-)
> >
> > diff --git a/tools/perf/tests/code-reading.c b/tools/perf/tests/code-reading.c
> > index 1545fcaa95c6..efe026a35010 100644
> > --- a/tools/perf/tests/code-reading.c
> > +++ b/tools/perf/tests/code-reading.c
> > @@ -366,6 +366,7 @@ static int read_object_code(u64 addr, size_t len, u8 cpumode,
> > }
> > pr_debug("Bytes read match those read by objdump\n");
> > out:
> > + map__put(al.map);
>
> Given that it is 'al' that is going away, wouldn't it be
> more logical to have here:
>
> addr_location__exit(&al);
>
> where:
>
> void addr_location__exit(struct addr_location *al)
> {
> if (al->map) {
> map__put(al->map);
> al->map = NULL;
> }
> }
I think making addr_location have an init, exit, etc. would be good.
There are some troublesome cases like struct hist_iter_ops where the
iteration function pass an addr_location. Wrt this patch series I
think we should try to land what's here and follow up. The biggest
issue the reference counting / address and leak sanitizer code is
pointing at is leaks with thread, so I'd prefer to follow up on that
first.
>
> > return err;
> > }
> >
> > diff --git a/tools/perf/tests/hists_cumulate.c b/tools/perf/tests/hists_cumulate.c
> > index f00ec9abdbcd..8c0e3f334747 100644
> > --- a/tools/perf/tests/hists_cumulate.c
> > +++ b/tools/perf/tests/hists_cumulate.c
> > @@ -112,6 +112,7 @@ static int add_hist_entries(struct hists *hists, struct machine *machine)
> > }
> >
> > fake_samples[i].thread = al.thread;
> > + map__put(fake_samples[i].map);
> > fake_samples[i].map = al.map;
> > fake_samples[i].sym = al.sym;
> > }
> > @@ -147,6 +148,14 @@ static void del_hist_entries(struct hists *hists)
> > }
> > }
> >
> > +static void put_fake_samples(void)
> > +{
> > + size_t i;
> > +
> > + for (i = 0; i < ARRAY_SIZE(fake_samples); i++)
> > + map__put(fake_samples[i].map);
> > +}
> > +
> > typedef int (*test_fn_t)(struct evsel *, struct machine *);
> >
> > #define COMM(he) (thread__comm_str(he->thread))
> > @@ -733,6 +742,7 @@ static int test__hists_cumulate(struct test_suite *test __maybe_unused, int subt
> > /* tear down everything */
> > evlist__delete(evlist);
> > machines__exit(&machines);
> > + put_fake_samples();
> >
> > return err;
> > }
> > diff --git a/tools/perf/tests/hists_filter.c b/tools/perf/tests/hists_filter.c
> > index 7c552549f4a4..98eff5935a1c 100644
> > --- a/tools/perf/tests/hists_filter.c
> > +++ b/tools/perf/tests/hists_filter.c
> > @@ -89,6 +89,7 @@ static int add_hist_entries(struct evlist *evlist,
> > }
> >
> > fake_samples[i].thread = al.thread;
> > + map__put(fake_samples[i].map);
> > fake_samples[i].map = al.map;
> > fake_samples[i].sym = al.sym;
> > }
> > @@ -101,6 +102,14 @@ static int add_hist_entries(struct evlist *evlist,
> > return TEST_FAIL;
> > }
> >
> > +static void put_fake_samples(void)
> > +{
> > + size_t i;
> > +
> > + for (i = 0; i < ARRAY_SIZE(fake_samples); i++)
> > + map__put(fake_samples[i].map);
> > +}
> > +
> > static int test__hists_filter(struct test_suite *test __maybe_unused, int subtest __maybe_unused)
> > {
> > int err = TEST_FAIL;
> > @@ -322,6 +331,7 @@ static int test__hists_filter(struct test_suite *test __maybe_unused, int subtes
> > evlist__delete(evlist);
> > reset_output_field();
> > machines__exit(&machines);
> > + put_fake_samples();
> >
> > return err;
> > }
> > diff --git a/tools/perf/tests/hists_link.c b/tools/perf/tests/hists_link.c
> > index e7e4ee57ce04..64ce8097889c 100644
> > --- a/tools/perf/tests/hists_link.c
> > +++ b/tools/perf/tests/hists_link.c
> > @@ -6,6 +6,7 @@
> > #include "evsel.h"
> > #include "evlist.h"
> > #include "machine.h"
> > +#include "map.h"
> > #include "parse-events.h"
> > #include "hists_common.h"
> > #include "util/mmap.h"
> > @@ -94,6 +95,7 @@ static int add_hist_entries(struct evlist *evlist, struct machine *machine)
> > }
> >
> > fake_common_samples[k].thread = al.thread;
> > + map__put(fake_common_samples[k].map);
> > fake_common_samples[k].map = al.map;
> > fake_common_samples[k].sym = al.sym;
> > }
> > @@ -126,11 +128,24 @@ static int add_hist_entries(struct evlist *evlist, struct machine *machine)
> > return -1;
> > }
> >
> > +static void put_fake_samples(void)
> > +{
> > + size_t i, j;
> > +
> > + for (i = 0; i < ARRAY_SIZE(fake_common_samples); i++)
> > + map__put(fake_common_samples[i].map);
> > + for (i = 0; i < ARRAY_SIZE(fake_samples); i++) {
> > + for (j = 0; j < ARRAY_SIZE(fake_samples[0]); j++)
> > + map__put(fake_samples[i][j].map);
> > + }
> > +}
> > +
> > static int find_sample(struct sample *samples, size_t nr_samples,
> > struct thread *t, struct map *m, struct symbol *s)
> > {
> > while (nr_samples--) {
> > - if (samples->thread == t && samples->map == m &&
> > + if (samples->thread == t &&
> > + samples->map == m &&
> > samples->sym == s)
> > return 1;
> > samples++;
> > @@ -336,6 +351,7 @@ static int test__hists_link(struct test_suite *test __maybe_unused, int subtest
> > evlist__delete(evlist);
> > reset_output_field();
> > machines__exit(&machines);
> > + put_fake_samples();
> >
> > return err;
> > }
> > diff --git a/tools/perf/tests/hists_output.c b/tools/perf/tests/hists_output.c
> > index 428d11a938f2..cebd5226bb12 100644
> > --- a/tools/perf/tests/hists_output.c
> > +++ b/tools/perf/tests/hists_output.c
> > @@ -78,6 +78,7 @@ static int add_hist_entries(struct hists *hists, struct machine *machine)
> > }
> >
> > fake_samples[i].thread = al.thread;
> > + map__put(fake_samples[i].map);
> > fake_samples[i].map = al.map;
> > fake_samples[i].sym = al.sym;
> > }
> > @@ -113,6 +114,14 @@ static void del_hist_entries(struct hists *hists)
> > }
> > }
> >
> > +static void put_fake_samples(void)
> > +{
> > + size_t i;
> > +
> > + for (i = 0; i < ARRAY_SIZE(fake_samples); i++)
> > + map__put(fake_samples[i].map);
> > +}
> > +
> > typedef int (*test_fn_t)(struct evsel *, struct machine *);
> >
> > #define COMM(he) (thread__comm_str(he->thread))
> > @@ -620,6 +629,7 @@ static int test__hists_output(struct test_suite *test __maybe_unused, int subtes
> > /* tear down everything */
> > evlist__delete(evlist);
> > machines__exit(&machines);
> > + put_fake_samples();
> >
> > return err;
> > }
> > diff --git a/tools/perf/tests/mmap-thread-lookup.c b/tools/perf/tests/mmap-thread-lookup.c
> > index 5cc4644e353d..898eda55b7a8 100644
> > --- a/tools/perf/tests/mmap-thread-lookup.c
> > +++ b/tools/perf/tests/mmap-thread-lookup.c
> > @@ -203,6 +203,7 @@ static int mmap_events(synth_cb synth)
> > }
> >
> > pr_debug("map %p, addr %" PRIx64 "\n", al.map, map__start(al.map));
> > + map__put(al.map);
> > }
> >
> > machine__delete_threads(machine);
> > diff --git a/tools/perf/util/callchain.c b/tools/perf/util/callchain.c
> > index 9e9c39dd9d2b..78dc7b6f7ff7 100644
> > --- a/tools/perf/util/callchain.c
> > +++ b/tools/perf/util/callchain.c
> > @@ -589,7 +589,7 @@ fill_node(struct callchain_node *node, struct callchain_cursor *cursor)
> > }
> > call->ip = cursor_node->ip;
> > call->ms = cursor_node->ms;
> > - map__get(call->ms.map);
> > + call->ms.map = map__get(call->ms.map);
> > call->srcline = cursor_node->srcline;
> >
> > if (cursor_node->branch) {
> > @@ -1067,7 +1067,7 @@ int callchain_cursor_append(struct callchain_cursor *cursor,
> > node->ip = ip;
> > map__zput(node->ms.map);
> > node->ms = *ms;
> > - map__get(node->ms.map);
> > + node->ms.map = map__get(node->ms.map);
> > node->branch = branch;
> > node->nr_loop_iter = nr_loop_iter;
> > node->iter_cycles = iter_cycles;
> > @@ -1115,7 +1115,8 @@ int fill_callchain_info(struct addr_location *al, struct callchain_cursor_node *
> > struct machine *machine = maps__machine(node->ms.maps);
> >
> > al->maps = node->ms.maps;
> > - al->map = node->ms.map;
> > + map__put(al->map);
> > + al->map = map__get(node->ms.map);
> > al->sym = node->ms.sym;
> > al->srcline = node->srcline;
> > al->addr = node->ip;
> > @@ -1528,7 +1529,7 @@ int callchain_node__make_parent_list(struct callchain_node *node)
> > goto out;
> > *new = *chain;
> > new->has_children = false;
> > - map__get(new->ms.map);
> > + new->ms.map = map__get(new->ms.map);
> > list_add_tail(&new->list, &head);
> > }
> > parent = parent->parent;
> > diff --git a/tools/perf/util/event.c b/tools/perf/util/event.c
> > index 2712d1a8264e..8293c8a3406b 100644
> > --- a/tools/perf/util/event.c
> > +++ b/tools/perf/util/event.c
> > @@ -485,13 +485,14 @@ size_t perf_event__fprintf_text_poke(union perf_event *event, struct machine *ma
> > if (machine) {
> > struct addr_location al;
> >
> > - al.map = maps__find(machine__kernel_maps(machine), tp->addr);
> > + al.map = map__get(maps__find(machine__kernel_maps(machine), tp->addr));
> > if (al.map && map__load(al.map) >= 0) {
> > al.addr = map__map_ip(al.map, tp->addr);
> > al.sym = map__find_symbol(al.map, al.addr);
> > if (al.sym)
> > ret += symbol__fprintf_symname_offs(al.sym, &al, fp);
> > }
> > + map__put(al.map);
> > }
> > ret += fprintf(fp, " old len %u new len %u\n", tp->old_len, tp->new_len);
> > old = true;
> > @@ -582,6 +583,7 @@ struct map *thread__find_map(struct thread *thread, u8 cpumode, u64 addr,
> > al->filtered = 0;
> >
> > if (machine == NULL) {
> > + map__put(al->map);
>
> Often as not, addr_location is not initialized before a call
> to thread__find_map(), so this is dereferencing an uninitialized
> pointer in those cases.
Agreed. I suspect this was an earlier fix for the struct hist_iter_ops
issues and I've now dropped this and the changes below in v5.
Thanks,
Ian
> > al->map = NULL;
> > return NULL;
> > }
> > @@ -600,6 +602,7 @@ struct map *thread__find_map(struct thread *thread, u8 cpumode, u64 addr,
> > al->level = 'u';
> > } else {
> > al->level = 'H';
> > + map__put(al->map);
>
> As above
>
> > al->map = NULL;
> >
> > if ((cpumode == PERF_RECORD_MISC_GUEST_USER ||
> > @@ -614,7 +617,7 @@ struct map *thread__find_map(struct thread *thread, u8 cpumode, u64 addr,
> > return NULL;
> > }
> >
> > - al->map = maps__find(maps, al->addr);
> > + al->map = map__get(maps__find(maps, al->addr));
>
> The map__put() above suggest there should one here before
> overwriting al->map?
>
> In general, it looks like there are callers of thread__find_map()
> that are not covered by this patch?
>
> > if (al->map != NULL) {
> > /*
> > * Kernel maps might be changed when loading symbols so loading
> > @@ -773,6 +776,7 @@ int machine__resolve(struct machine *machine, struct addr_location *al,
> > */
> > void addr_location__put(struct addr_location *al)
> > {
> > + map__zput(al->map);
> > thread__zput(al->thread);
> > }
> >
> > diff --git a/tools/perf/util/hist.c b/tools/perf/util/hist.c
> > index fdf0562d2fd3..02b4bf31b1a7 100644
> > --- a/tools/perf/util/hist.c
> > +++ b/tools/perf/util/hist.c
> > @@ -450,7 +450,7 @@ static int hist_entry__init(struct hist_entry *he,
> > memset(&he->stat, 0, sizeof(he->stat));
> > }
> >
> > - map__get(he->ms.map);
> > + he->ms.map = map__get(he->ms.map);
> >
> > if (he->branch_info) {
> > /*
> > @@ -465,13 +465,13 @@ static int hist_entry__init(struct hist_entry *he,
> > memcpy(he->branch_info, template->branch_info,
> > sizeof(*he->branch_info));
> >
> > - map__get(he->branch_info->from.ms.map);
> > - map__get(he->branch_info->to.ms.map);
> > + he->branch_info->from.ms.map = map__get(he->branch_info->from.ms.map);
> > + he->branch_info->to.ms.map = map__get(he->branch_info->to.ms.map);
> > }
> >
> > if (he->mem_info) {
> > - map__get(he->mem_info->iaddr.ms.map);
> > - map__get(he->mem_info->daddr.ms.map);
> > + he->mem_info->iaddr.ms.map = map__get(he->mem_info->iaddr.ms.map);
> > + he->mem_info->daddr.ms.map = map__get(he->mem_info->daddr.ms.map);
> > }
> >
> > if (hist_entry__has_callchains(he) && symbol_conf.use_callchain)
> > diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c
> > index 916d98885128..502e97010a3c 100644
> > --- a/tools/perf/util/machine.c
> > +++ b/tools/perf/util/machine.c
> > @@ -880,21 +880,29 @@ static int machine__process_ksymbol_register(struct machine *machine,
> > struct symbol *sym;
> > struct dso *dso;
> > struct map *map = maps__find(machine__kernel_maps(machine), event->ksymbol.addr);
> > + bool put_map = false;
> > + int err = 0;
> >
> > if (!map) {
> > - int err;
> > -
> > dso = dso__new(event->ksymbol.name);
> > - if (dso) {
> > - dso->kernel = DSO_SPACE__KERNEL;
> > - map = map__new2(0, dso);
> > - dso__put(dso);
> > - }
> >
> > - if (!dso || !map) {
> > - return -ENOMEM;
> > + if (!dso) {
> > + err = -ENOMEM;
> > + goto out;
> > }
> > -
> > + dso->kernel = DSO_SPACE__KERNEL;
> > + map = map__new2(0, dso);
> > + dso__put(dso);
> > + if (!map) {
> > + err = -ENOMEM;
> > + goto out;
> > + }
> > + /*
> > + * The inserted map has a get on it, we need to put to release
> > + * the reference count here, but do it after all accesses are
> > + * done.
> > + */
> > + put_map = true;
> > if (event->ksymbol.ksym_type == PERF_RECORD_KSYMBOL_TYPE_OOL) {
> > dso->binary_type = DSO_BINARY_TYPE__OOL;
> > dso->data.file_size = event->ksymbol.len;
> > @@ -904,9 +912,10 @@ static int machine__process_ksymbol_register(struct machine *machine,
> > map->start = event->ksymbol.addr;
> > map->end = map__start(map) + event->ksymbol.len;
> > err = maps__insert(machine__kernel_maps(machine), map);
> > - map__put(map);
> > - if (err)
> > - return err;
> > + if (err) {
> > + err = -ENOMEM;
> > + goto out;
> > + }
> >
> > dso__set_loaded(dso);
> >
> > @@ -921,10 +930,15 @@ static int machine__process_ksymbol_register(struct machine *machine,
> > sym = symbol__new(map__map_ip(map, map__start(map)),
> > event->ksymbol.len,
> > 0, 0, event->ksymbol.name);
> > - if (!sym)
> > - return -ENOMEM;
> > + if (!sym) {
> > + err = -ENOMEM;
> > + goto out;
> > + }
> > dso__insert_symbol(dso, sym);
> > - return 0;
> > +out:
> > + if (put_map)
> > + map__put(map);
> > + return err;
> > }
> >
> > static int machine__process_ksymbol_unregister(struct machine *machine,
> > @@ -1026,13 +1040,11 @@ static struct map *machine__addnew_module_map(struct machine *machine, u64 start
> > goto out;
> >
> > err = maps__insert(machine__kernel_maps(machine), map);
> > -
> > - /* Put the map here because maps__insert already got it */
> > - map__put(map);
> > -
> > /* If maps__insert failed, return NULL. */
> > - if (err)
> > + if (err) {
> > + map__put(map);
> > map = NULL;
> > + }
> > out:
> > /* put the dso here, corresponding to machine__findnew_module_dso */
> > dso__put(dso);
> > @@ -1324,6 +1336,7 @@ __machine__create_kernel_maps(struct machine *machine, struct dso *kernel)
> > /* In case of renewal the kernel map, destroy previous one */
> > machine__destroy_kernel_maps(machine);
> >
> > + map__put(machine->vmlinux_map);
> > machine->vmlinux_map = map__new2(0, kernel);
> > if (machine->vmlinux_map == NULL)
> > return -ENOMEM;
> > @@ -1612,7 +1625,7 @@ static int machine__create_module(void *arg, const char *name, u64 start,
> > map->end = start + size;
> >
> > dso__kernel_module_get_build_id(map__dso(map), machine->root_dir);
> > -
> > + map__put(map);
> > return 0;
> > }
> >
> > @@ -1658,16 +1671,18 @@ static void machine__set_kernel_mmap(struct machine *machine,
> > static int machine__update_kernel_mmap(struct machine *machine,
> > u64 start, u64 end)
> > {
> > - struct map *map = machine__kernel_map(machine);
> > + struct map *orig, *updated;
> > int err;
> >
> > - map__get(map);
> > - maps__remove(machine__kernel_maps(machine), map);
> > + orig = machine->vmlinux_map;
> > + updated = map__get(orig);
> >
> > + machine->vmlinux_map = updated;
> > machine__set_kernel_mmap(machine, start, end);
> > + maps__remove(machine__kernel_maps(machine), orig);
> > + err = maps__insert(machine__kernel_maps(machine), updated);
> > + map__put(orig);
> >
> > - err = maps__insert(machine__kernel_maps(machine), map);
> > - map__put(map);
> > return err;
> > }
> >
> > @@ -2294,7 +2309,7 @@ static int add_callchain_ip(struct thread *thread,
> > {
> > struct map_symbol ms;
> > struct addr_location al;
> > - int nr_loop_iter = 0;
> > + int nr_loop_iter = 0, err;
> > u64 iter_cycles = 0;
> > const char *srcline = NULL;
> >
> > @@ -2355,9 +2370,11 @@ static int add_callchain_ip(struct thread *thread,
> > ms.map = al.map;
> > ms.sym = al.sym;
> > srcline = callchain_srcline(&ms, al.addr);
> > - return callchain_cursor_append(cursor, ip, &ms,
> > - branch, flags, nr_loop_iter,
> > - iter_cycles, branch_from, srcline);
> > + err = callchain_cursor_append(cursor, ip, &ms,
> > + branch, flags, nr_loop_iter,
> > + iter_cycles, branch_from, srcline);
> > + map__put(al.map);
> > + return err;
> > }
> >
> > struct branch_info *sample__resolve_bstack(struct perf_sample *sample,
> > diff --git a/tools/perf/util/map.c b/tools/perf/util/map.c
> > index 1fe367e2cf19..acbc37359e06 100644
> > --- a/tools/perf/util/map.c
> > +++ b/tools/perf/util/map.c
> > @@ -410,7 +410,7 @@ struct map *map__clone(struct map *from)
> > map = memdup(from, size);
> > if (map != NULL) {
> > refcount_set(&map->refcnt, 1);
> > - dso__get(dso);
> > + map->dso = dso__get(dso);
> > }
> >
> > return map;
>
Powered by blists - more mailing lists