Re: [PATCH v3 12/22] perf maps: Remove rb_node from struct map

From: Ian Rogers
Date: Wed Feb 16 2022 - 12:36:47 EST

On Wed, Feb 16, 2022 at 6:08 AM Arnaldo Carvalho de Melo
<acme@xxxxxxxxxx> wrote:
>
> Em Fri, Feb 11, 2022 at 02:34:05AM -0800, Ian Rogers escreveu:
> > struct map is reference counted, having it also be a node in an
> > red-black tree complicates the reference counting.
>
> In what way?
>
> If I have some refcounted data structure and I want to add it to some
> container (an rb_tree, a list, etc) all I have to do is to grab a
> refcount when adding and dropping it after removing it from the list.
>
> IOW, in other words it is refcounted so that we can add it to a
> red-black tree, amongst other uses.

Thanks Arnaldo. So I'm not disputing that you can make reference
counted collections. With reference counting every reference should
have a count associated with it. So when symbol.c is using the list, a
node may be referenced from a prev and a next pointer, so being in the
list requires a reference count of 2. When you find something in the
list which reference count is that associated with? It doesn't matter
normally as you'd increment the reference count again and return that.
In the perf code find doesn't increment a reference count so I want to
return the "get" that belongs to the list. That's "get" singular,
hence wanting to add in the pointer indirection that incurs cost. To
make insertion and deletion work properly on list with a reference
count means reworking list.h.

The rbtree is the same problem only more-so, as you need pointers for
parent, left and right child.

> > Switch to having a map_rb_node which is a red-block tree node but
> > points at the reference counted struct map. This reference is
> > responsible for a single reference count.
>
> This makes every insertion incur in an allocation that has to be
> checked, etc, when we know that maps will live in rb_trees, so having
> the node structure allocated at the same time as the map is
> advantageous.

So this pattern is common in other languages, the default kernel style
is what at Google gets called invasive - you put the storage for list
nodes, reference counts, etc. into the referenced object itself. This
lowers the overhead within the struct, and I don't disagree it adds a
cost to insertion, unless maps are shared which isn't a use-case we
have at the moment. So this change is backing out an optimization, but
frankly fixing this properly is a much bigger overhaul than this
already big overhaul and I don't think losing the optimization is
really costing that much performance - a memory allocation costs in
the region of 40 cycles with an optimized implementation like
tcmalloc. We also don't use the invasive style for maps_by_name, it is
just a sorted array.

A side note, I see a lot of overhead in symbol allocation and part of
that is the size of the two invasive rbtree nodes (2 * 3 * 8 bytes =
48bytes). Were the symbols just referenced by a sorted array, like
maps_by_name, insertion and sorting would still be O(n*log(n)) but
we'd reduce the memory usage to a third. rbtree is a cool data
structure, but I think we could be over using it.

> We don't have to check if adding a data structure to a rbtree works, as
> all that is needed is already preallocated.

The issue here is that a find, or similar, wants to pass around
something that is owned by a list or an rbtree. We can have the idea
of ownership by adding a token/cookie and passing that around
everywhere, it gets problematic then to spot use after put and I think
that approach is overall more invasive to the APIs than what is in
these changes.

A better solution can be to keep the rbtree being invasive and at all
the find and similar routines, make sure a getted version is returned
- so the code outside of maps is never working with the rbtree's
reference counted version. The problem with this is that it is an
overhaul to all the uses of map. The reference count checker would
find misuse but again it'd be a far large patch series than what is
here - that is trying to fix the code base as it is.

I think the having our cake and eating solution (best performance +
checking) is that approach, but we need to get to a point where
checking is working. So if we focus on (1) checking and fixing those
bugs (the changes here), then (2) change the APIs so that everything
is getted and fix the leaks that introduces, then (3) go back to being
invasive I think we get to that solution. I like step (2) from a
cleanliness point-of-view, I'm fine with (3) I'm just not sure anybody
would notice the performance difference.

Thanks,
Ian

> - Arnaldo
>
> > Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx>
> > ---
> > tools/perf/arch/x86/util/event.c | 13 +-
> > tools/perf/builtin-report.c | 6 +-
> > tools/perf/tests/maps.c | 8 +-
> > tools/perf/tests/vmlinux-kallsyms.c | 17 +--
> > tools/perf/util/machine.c | 62 ++++++----
> > tools/perf/util/map.c | 16 ---
> > tools/perf/util/map.h | 1 -
> > tools/perf/util/maps.c | 182 ++++++++++++++++++----------
> > tools/perf/util/maps.h | 17 ++-
> > tools/perf/util/probe-event.c | 18 +--
> > tools/perf/util/symbol-elf.c | 9 +-
> > tools/perf/util/symbol.c | 77 +++++++-----
> > tools/perf/util/synthetic-events.c | 26 ++--
> > tools/perf/util/thread.c | 10 +-
> > tools/perf/util/vdso.c | 7 +-
> > 15 files changed, 288 insertions(+), 181 deletions(-)
> >
> > diff --git a/tools/perf/arch/x86/util/event.c b/tools/perf/arch/x86/util/event.c
> > index e670f3547581..7b6b0c98fb36 100644
> > --- a/tools/perf/arch/x86/util/event.c
> > +++ b/tools/perf/arch/x86/util/event.c
> > @@ -17,7 +17,7 @@ int perf_event__synthesize_extra_kmaps(struct perf_tool *tool,
> > struct machine *machine)
> > {
> > int rc = 0;
> > - struct map *pos;
> > + struct map_rb_node *pos;
> > struct maps *kmaps = machine__kernel_maps(machine);
> > union perf_event *event = zalloc(sizeof(event->mmap) +
> > machine->id_hdr_size);
> > @@ -31,11 +31,12 @@ int perf_event__synthesize_extra_kmaps(struct perf_tool *tool,
> > maps__for_each_entry(kmaps, pos) {
> > struct kmap *kmap;
> > size_t size;
> > + struct map *map = pos->map;
> >
> > - if (!__map__is_extra_kernel_map(pos))
> > + if (!__map__is_extra_kernel_map(map))
> > continue;
> >
> > - kmap = map__kmap(pos);
> > + kmap = map__kmap(map);
> >
> > size = sizeof(event->mmap) - sizeof(event->mmap.filename) +
> > PERF_ALIGN(strlen(kmap->name) + 1, sizeof(u64)) +
> > @@ -56,9 +57,9 @@ int perf_event__synthesize_extra_kmaps(struct perf_tool *tool,
> >
> > event->mmap.header.size = size;
> >
> > - event->mmap.start = pos->start;
> > - event->mmap.len = pos->end - pos->start;
> > - event->mmap.pgoff = pos->pgoff;
> > + event->mmap.start = map->start;
> > + event->mmap.len = map->end - map->start;
> > + event->mmap.pgoff = map->pgoff;
> > event->mmap.pid = machine->pid;
> >
> > strlcpy(event->mmap.filename, kmap->name, PATH_MAX);
> > diff --git a/tools/perf/builtin-report.c b/tools/perf/builtin-report.c
> > index 1dd92d8c9279..57611ef725c3 100644
> > --- a/tools/perf/builtin-report.c
> > +++ b/tools/perf/builtin-report.c
> > @@ -799,9 +799,11 @@ static struct task *tasks_list(struct task *task, struct machine *machine)
> > static size_t maps__fprintf_task(struct maps *maps, int indent, FILE *fp)
> > {
> > size_t printed = 0;
> > - struct map *map;
> > + struct map_rb_node *rb_node;
> > +
> > + maps__for_each_entry(maps, rb_node) {
> > + struct map *map = rb_node->map;
> >
> > - maps__for_each_entry(maps, map) {
> > printed += fprintf(fp, "%*s %" PRIx64 "-%" PRIx64 " %c%c%c%c %08" PRIx64 " %" PRIu64 " %s\n",
> > indent, "", map->start, map->end,
> > map->prot & PROT_READ ? 'r' : '-',
> > diff --git a/tools/perf/tests/maps.c b/tools/perf/tests/maps.c
> > index 6f53f17f788e..a58274598587 100644
> > --- a/tools/perf/tests/maps.c
> > +++ b/tools/perf/tests/maps.c
> > @@ -15,10 +15,12 @@ struct map_def {
> >
> > static int check_maps(struct map_def *merged, unsigned int size, struct maps *maps)
> > {
> > - struct map *map;
> > + struct map_rb_node *rb_node;
> > unsigned int i = 0;
> >
> > - maps__for_each_entry(maps, map) {
> > + maps__for_each_entry(maps, rb_node) {
> > + struct map *map = rb_node->map;
> > +
> > if (i > 0)
> > TEST_ASSERT_VAL("less maps expected", (map && i < size) || (!map && i == size));
> >
> > @@ -74,7 +76,7 @@ static int test__maps__merge_in(struct test_suite *t __maybe_unused, int subtest
> >
> > map->start = bpf_progs[i].start;
> > map->end = bpf_progs[i].end;
> > - maps__insert(maps, map);
> > + TEST_ASSERT_VAL("failed to insert map", maps__insert(maps, map) == 0);
> > map__put(map);
> > }
> >
> > diff --git a/tools/perf/tests/vmlinux-kallsyms.c b/tools/perf/tests/vmlinux-kallsyms.c
> > index 84bf5f640065..11a230ee5894 100644
> > --- a/tools/perf/tests/vmlinux-kallsyms.c
> > +++ b/tools/perf/tests/vmlinux-kallsyms.c
> > @@ -117,7 +117,8 @@ static int test__vmlinux_matches_kallsyms(struct test_suite *test __maybe_unused
> > int err = -1;
> > struct rb_node *nd;
> > struct symbol *sym;
> > - struct map *kallsyms_map, *vmlinux_map, *map;
> > + struct map *kallsyms_map, *vmlinux_map;
> > + struct map_rb_node *rb_node;
> > struct machine kallsyms, vmlinux;
> > struct maps *maps = machine__kernel_maps(&vmlinux);
> > u64 mem_start, mem_end;
> > @@ -285,15 +286,15 @@ static int test__vmlinux_matches_kallsyms(struct test_suite *test __maybe_unused
> >
> > header_printed = false;
> >
> > - maps__for_each_entry(maps, map) {
> > - struct map *
> > + maps__for_each_entry(maps, rb_node) {
> > + struct map *map = rb_node->map;
> > /*
> > * If it is the kernel, kallsyms is always "[kernel.kallsyms]", while
> > * the kernel will have the path for the vmlinux file being used,
> > * so use the short name, less descriptive but the same ("[kernel]" in
> > * both cases.
> > */
> > - pair = maps__find_by_name(kallsyms.kmaps, (map->dso->kernel ?
> > + struct map *pair = maps__find_by_name(kallsyms.kmaps, (map->dso->kernel ?
> > map->dso->short_name :
> > map->dso->name));
> > if (pair) {
> > @@ -309,8 +310,8 @@ static int test__vmlinux_matches_kallsyms(struct test_suite *test __maybe_unused
> >
> > header_printed = false;
> >
> > - maps__for_each_entry(maps, map) {
> > - struct map *pair;
> > + maps__for_each_entry(maps, rb_node) {
> > + struct map *pair, *map = rb_node->map;
> >
> > mem_start = vmlinux_map->unmap_ip(vmlinux_map, map->start);
> > mem_end = vmlinux_map->unmap_ip(vmlinux_map, map->end);
> > @@ -339,7 +340,9 @@ static int test__vmlinux_matches_kallsyms(struct test_suite *test __maybe_unused
> >
> > maps = machine__kernel_maps(&kallsyms);
> >
> > - maps__for_each_entry(maps, map) {
> > + maps__for_each_entry(maps, rb_node) {
> > + struct map *map = rb_node->map;
> > +
> > if (!map->priv) {
> > if (!header_printed) {
> > pr_info("WARN: Maps only in kallsyms:\n");
> > diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c
> > index 57fbdba66425..fa25174cabf7 100644
> > --- a/tools/perf/util/machine.c
> > +++ b/tools/perf/util/machine.c
> > @@ -786,6 +786,7 @@ static int machine__process_ksymbol_register(struct machine *machine,
> >
> > if (!map) {
> > struct dso *dso = dso__new(event->ksymbol.name);
> > + int err;
> >
> > if (dso) {
> > dso->kernel = DSO_SPACE__KERNEL;
> > @@ -805,8 +806,11 @@ static int machine__process_ksymbol_register(struct machine *machine,
> >
> > map->start = event->ksymbol.addr;
> > map->end = map->start + event->ksymbol.len;
> > - maps__insert(machine__kernel_maps(machine), map);
> > + err = maps__insert(machine__kernel_maps(machine), map);
> > map__put(map);
> > + if (err)
> > + return err;
> > +
> > dso__set_loaded(dso);
> >
> > if (is_bpf_image(event->ksymbol.name)) {
> > @@ -906,6 +910,7 @@ static struct map *machine__addnew_module_map(struct machine *machine, u64 start
> > struct map *map = NULL;
> > struct kmod_path m;
> > struct dso *dso;
> > + int err;
> >
> > if (kmod_path__parse_name(&m, filename))
> > return NULL;
> > @@ -918,10 +923,14 @@ static struct map *machine__addnew_module_map(struct machine *machine, u64 start
> > if (map == NULL)
> > goto out;
> >
> > - maps__insert(machine__kernel_maps(machine), map);
> > + 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)
> > + map = NULL;
> > out:
> > /* put the dso here, corresponding to machine__findnew_module_dso */
> > dso__put(dso);
> > @@ -1092,10 +1101,11 @@ int machine__create_extra_kernel_map(struct machine *machine,
> > {
> > struct kmap *kmap;
> > struct map *map;
> > + int err;
> >
> > map = map__new2(xm->start, kernel);
> > if (!map)
> > - return -1;
> > + return -ENOMEM;
> >
> > map->end = xm->end;
> > map->pgoff = xm->pgoff;
> > @@ -1104,14 +1114,16 @@ int machine__create_extra_kernel_map(struct machine *machine,
> >
> > strlcpy(kmap->name, xm->name, KMAP_NAME_LEN);
> >
> > - maps__insert(machine__kernel_maps(machine), map);
> > + err = maps__insert(machine__kernel_maps(machine), map);
> >
> > - pr_debug2("Added extra kernel map %s %" PRIx64 "-%" PRIx64 "\n",
> > - kmap->name, map->start, map->end);
> > + if (!err) {
> > + pr_debug2("Added extra kernel map %s %" PRIx64 "-%" PRIx64 "\n",
> > + kmap->name, map->start, map->end);
> > + }
> >
> > map__put(map);
> >
> > - return 0;
> > + return err;
> > }
> >
> > static u64 find_entry_trampoline(struct dso *dso)
> > @@ -1152,16 +1164,16 @@ int machine__map_x86_64_entry_trampolines(struct machine *machine,
> > struct maps *kmaps = machine__kernel_maps(machine);
> > int nr_cpus_avail, cpu;
> > bool found = false;
> > - struct map *map;
> > + struct map_rb_node *rb_node;
> > u64 pgoff;
> >
> > /*
> > * In the vmlinux case, pgoff is a virtual address which must now be
> > * mapped to a vmlinux offset.
> > */
> > - maps__for_each_entry(kmaps, map) {
> > + maps__for_each_entry(kmaps, rb_node) {
> > + struct map *dest_map, *map = rb_node->map;
> > struct kmap *kmap = __map__kmap(map);
> > - struct map *dest_map;
> >
> > if (!kmap || !is_entry_trampoline(kmap->name))
> > continue;
> > @@ -1216,11 +1228,10 @@ __machine__create_kernel_maps(struct machine *machine, struct dso *kernel)
> >
> > machine->vmlinux_map = map__new2(0, kernel);
> > if (machine->vmlinux_map == NULL)
> > - return -1;
> > + return -ENOMEM;
> >
> > machine->vmlinux_map->map_ip = machine->vmlinux_map->unmap_ip = identity__map_ip;
> > - maps__insert(machine__kernel_maps(machine), machine->vmlinux_map);
> > - return 0;
> > + return maps__insert(machine__kernel_maps(machine), machine->vmlinux_map);
> > }
> >
> > void machine__destroy_kernel_maps(struct machine *machine)
> > @@ -1542,25 +1553,26 @@ static void machine__set_kernel_mmap(struct machine *machine,
> > machine->vmlinux_map->end = ~0ULL;
> > }
> >
> > -static void machine__update_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);
> > + int err;
> >
> > map__get(map);
> > maps__remove(machine__kernel_maps(machine), map);
> >
> > machine__set_kernel_mmap(machine, start, end);
> >
> > - maps__insert(machine__kernel_maps(machine), map);
> > + err = maps__insert(machine__kernel_maps(machine), map);
> > map__put(map);
> > + return err;
> > }
> >
> > int machine__create_kernel_maps(struct machine *machine)
> > {
> > struct dso *kernel = machine__get_kernel(machine);
> > const char *name = NULL;
> > - struct map *map;
> > u64 start = 0, end = ~0ULL;
> > int ret;
> >
> > @@ -1592,7 +1604,9 @@ int machine__create_kernel_maps(struct machine *machine)
> > * we have a real start address now, so re-order the kmaps
> > * assume it's the last in the kmaps
> > */
> > - machine__update_kernel_mmap(machine, start, end);
> > + ret = machine__update_kernel_mmap(machine, start, end);
> > + if (ret < 0)
> > + goto out_put;
> > }
> >
> > if (machine__create_extra_kernel_maps(machine, kernel))
> > @@ -1600,9 +1614,12 @@ int machine__create_kernel_maps(struct machine *machine)
> >
> > if (end == ~0ULL) {
> > /* update end address of the kernel map using adjacent module address */
> > - map = map__next(machine__kernel_map(machine));
> > - if (map)
> > - machine__set_kernel_mmap(machine, start, map->start);
> > + struct map_rb_node *rb_node = maps__find_node(machine__kernel_maps(machine),
> > + machine__kernel_map(machine));
> > + struct map_rb_node *next = map_rb_node__next(rb_node);
> > +
> > + if (next)
> > + machine__set_kernel_mmap(machine, start, next->map->start);
> > }
> >
> > out_put:
> > @@ -1726,7 +1743,10 @@ static int machine__process_kernel_mmap_event(struct machine *machine,
> > if (strstr(kernel->long_name, "vmlinux"))
> > dso__set_short_name(kernel, "[kernel.vmlinux]", false);
> >
> > - machine__update_kernel_mmap(machine, xm->start, xm->end);
> > + if (machine__update_kernel_mmap(machine, xm->start, xm->end) < 0) {
> > + dso__put(kernel);
> > + goto out_problem;
> > + }
> >
> > if (build_id__is_defined(bid))
> > dso__set_build_id(kernel, bid);
> > diff --git a/tools/perf/util/map.c b/tools/perf/util/map.c
> > index 8bbf9246a3cf..dfa5f6b7381f 100644
> > --- a/tools/perf/util/map.c
> > +++ b/tools/perf/util/map.c
> > @@ -111,7 +111,6 @@ void map__init(struct map *map, u64 start, u64 end, u64 pgoff, struct dso *dso)
> > map->dso = dso__get(dso);
> > map->map_ip = map__map_ip;
> > map->unmap_ip = map__unmap_ip;
> > - RB_CLEAR_NODE(&map->rb_node);
> > map->erange_warned = false;
> > refcount_set(&map->refcnt, 1);
> > }
> > @@ -383,7 +382,6 @@ struct map *map__clone(struct map *from)
> > map = memdup(from, size);
> > if (map != NULL) {
> > refcount_set(&map->refcnt, 1);
> > - RB_CLEAR_NODE(&map->rb_node);
> > dso__get(map->dso);
> > }
> >
> > @@ -523,20 +521,6 @@ bool map__contains_symbol(const struct map *map, const struct symbol *sym)
> > return ip >= map->start && ip < map->end;
> > }
> >
> > -static struct map *__map__next(struct map *map)
> > -{
> > - struct rb_node *next = rb_next(&map->rb_node);
> > -
> > - if (next)
> > - return rb_entry(next, struct map, rb_node);
> > - return NULL;
> > -}
> > -
> > -struct map *map__next(struct map *map)
> > -{
> > - return map ? __map__next(map) : NULL;
> > -}
> > -
> > struct kmap *__map__kmap(struct map *map)
> > {
> > if (!map->dso || !map->dso->kernel)
> > diff --git a/tools/perf/util/map.h b/tools/perf/util/map.h
> > index 2879cae05ee0..d1a6f85fd31d 100644
> > --- a/tools/perf/util/map.h
> > +++ b/tools/perf/util/map.h
> > @@ -16,7 +16,6 @@ struct maps;
> > struct machine;
> >
> > struct map {
> > - struct rb_node rb_node;
> > u64 start;
> > u64 end;
> > bool erange_warned:1;
> > diff --git a/tools/perf/util/maps.c b/tools/perf/util/maps.c
> > index ededabf0a230..beb09b9a122c 100644
> > --- a/tools/perf/util/maps.c
> > +++ b/tools/perf/util/maps.c
> > @@ -10,9 +10,7 @@
> > #include "ui/ui.h"
> > #include "unwind.h"
> >
> > -static void __maps__insert(struct maps *maps, struct map *map);
> > -
> > -void maps__init(struct maps *maps, struct machine *machine)
> > +static void maps__init(struct maps *maps, struct machine *machine)
> > {
> > maps->entries = RB_ROOT;
> > init_rwsem(&maps->lock);
> > @@ -32,10 +30,44 @@ static void __maps__free_maps_by_name(struct maps *maps)
> > maps->nr_maps_allocated = 0;
> > }
> >
> > -void maps__insert(struct maps *maps, struct map *map)
> > +static int __maps__insert(struct maps *maps, struct map *map)
> > +{
> > + struct rb_node **p = &maps->entries.rb_node;
> > + struct rb_node *parent = NULL;
> > + const u64 ip = map->start;
> > + struct map_rb_node *m, *new_rb_node;
> > +
> > + new_rb_node = malloc(sizeof(*new_rb_node));
> > + if (!new_rb_node)
> > + return -ENOMEM;
> > +
> > + RB_CLEAR_NODE(&new_rb_node->rb_node);
> > + new_rb_node->map = map;
> > +
> > + while (*p != NULL) {
> > + parent = *p;
> > + m = rb_entry(parent, struct map_rb_node, rb_node);
> > + if (ip < m->map->start)
> > + p = &(*p)->rb_left;
> > + else
> > + p = &(*p)->rb_right;
> > + }
> > +
> > + rb_link_node(&new_rb_node->rb_node, parent, p);
> > + rb_insert_color(&new_rb_node->rb_node, &maps->entries);
> > + map__get(map);
> > + return 0;
> > +}
> > +
> > +int maps__insert(struct maps *maps, struct map *map)
> > {
> > + int err;
> > +
> > down_write(&maps->lock);
> > - __maps__insert(maps, map);
> > + err = __maps__insert(maps, map);
> > + if (err)
> > + goto out;
> > +
> > ++maps->nr_maps;
> >
> > if (map->dso && map->dso->kernel) {
> > @@ -59,8 +91,8 @@ void maps__insert(struct maps *maps, struct map *map)
> >
> > if (maps_by_name == NULL) {
> > __maps__free_maps_by_name(maps);
> > - up_write(&maps->lock);
> > - return;
> > + err = -ENOMEM;
> > + goto out;
> > }
> >
> > maps->maps_by_name = maps_by_name;
> > @@ -69,22 +101,29 @@ void maps__insert(struct maps *maps, struct map *map)
> > maps->maps_by_name[maps->nr_maps - 1] = map;
> > __maps__sort_by_name(maps);
> > }
> > +out:
> > up_write(&maps->lock);
> > + return err;
> > }
> >
> > -static void __maps__remove(struct maps *maps, struct map *map)
> > +static void __maps__remove(struct maps *maps, struct map_rb_node *rb_node)
> > {
> > - rb_erase_init(&map->rb_node, &maps->entries);
> > - map__put(map);
> > + rb_erase_init(&rb_node->rb_node, &maps->entries);
> > + map__put(rb_node->map);
> > + free(rb_node);
> > }
> >
> > void maps__remove(struct maps *maps, struct map *map)
> > {
> > + struct map_rb_node *rb_node;
> > +
> > down_write(&maps->lock);
> > if (maps->last_search_by_name == map)
> > maps->last_search_by_name = NULL;
> >
> > - __maps__remove(maps, map);
> > + rb_node = maps__find_node(maps, map);
> > + assert(rb_node->map == map);
> > + __maps__remove(maps, rb_node);
> > --maps->nr_maps;
> > if (maps->maps_by_name)
> > __maps__free_maps_by_name(maps);
> > @@ -93,15 +132,16 @@ void maps__remove(struct maps *maps, struct map *map)
> >
> > static void __maps__purge(struct maps *maps)
> > {
> > - struct map *pos, *next;
> > + struct map_rb_node *pos, *next;
> >
> > maps__for_each_entry_safe(maps, pos, next) {
> > rb_erase_init(&pos->rb_node, &maps->entries);
> > - map__put(pos);
> > + map__put(pos->map);
> > + free(pos);
> > }
> > }
> >
> > -void maps__exit(struct maps *maps)
> > +static void maps__exit(struct maps *maps)
> > {
> > down_write(&maps->lock);
> > __maps__purge(maps);
> > @@ -153,21 +193,21 @@ struct symbol *maps__find_symbol(struct maps *maps, u64 addr, struct map **mapp)
> > struct symbol *maps__find_symbol_by_name(struct maps *maps, const char *name, struct map **mapp)
> > {
> > struct symbol *sym;
> > - struct map *pos;
> > + struct map_rb_node *pos;
> >
> > down_read(&maps->lock);
> >
> > maps__for_each_entry(maps, pos) {
> > - sym = map__find_symbol_by_name(pos, name);
> > + sym = map__find_symbol_by_name(pos->map, name);
> >
> > if (sym == NULL)
> > continue;
> > - if (!map__contains_symbol(pos, sym)) {
> > + if (!map__contains_symbol(pos->map, sym)) {
> > sym = NULL;
> > continue;
> > }
> > if (mapp != NULL)
> > - *mapp = pos;
> > + *mapp = pos->map;
> > goto out;
> > }
> >
> > @@ -196,15 +236,15 @@ int maps__find_ams(struct maps *maps, struct addr_map_symbol *ams)
> > size_t maps__fprintf(struct maps *maps, FILE *fp)
> > {
> > size_t printed = 0;
> > - struct map *pos;
> > + struct map_rb_node *pos;
> >
> > down_read(&maps->lock);
> >
> > maps__for_each_entry(maps, pos) {
> > printed += fprintf(fp, "Map:");
> > - printed += map__fprintf(pos, fp);
> > + printed += map__fprintf(pos->map, fp);
> > if (verbose > 2) {
> > - printed += dso__fprintf(pos->dso, fp);
> > + printed += dso__fprintf(pos->map->dso, fp);
> > printed += fprintf(fp, "--\n");
> > }
> > }
> > @@ -231,11 +271,11 @@ int maps__fixup_overlappings(struct maps *maps, struct map *map, FILE *fp)
> > next = root->rb_node;
> > first = NULL;
> > while (next) {
> > - struct map *pos = rb_entry(next, struct map, rb_node);
> > + struct map_rb_node *pos = rb_entry(next, struct map_rb_node, rb_node);
> >
> > - if (pos->end > map->start) {
> > + if (pos->map->end > map->start) {
> > first = next;
> > - if (pos->start <= map->start)
> > + if (pos->map->start <= map->start)
> > break;
> > next = next->rb_left;
> > } else
> > @@ -244,14 +284,14 @@ int maps__fixup_overlappings(struct maps *maps, struct map *map, FILE *fp)
> >
> > next = first;
> > while (next) {
> > - struct map *pos = rb_entry(next, struct map, rb_node);
> > + struct map_rb_node *pos = rb_entry(next, struct map_rb_node, rb_node);
> > next = rb_next(&pos->rb_node);
> >
> > /*
> > * Stop if current map starts after map->end.
> > * Maps are ordered by start: next will not overlap for sure.
> > */
> > - if (pos->start >= map->end)
> > + if (pos->map->start >= map->end)
> > break;
> >
> > if (verbose >= 2) {
> > @@ -262,7 +302,7 @@ int maps__fixup_overlappings(struct maps *maps, struct map *map, FILE *fp)
> > } else {
> > fputs("overlapping maps:\n", fp);
> > map__fprintf(map, fp);
> > - map__fprintf(pos, fp);
> > + map__fprintf(pos->map, fp);
> > }
> > }
> >
> > @@ -271,8 +311,8 @@ int maps__fixup_overlappings(struct maps *maps, struct map *map, FILE *fp)
> > * Now check if we need to create new maps for areas not
> > * overlapped by the new map:
> > */
> > - if (map->start > pos->start) {
> > - struct map *before = map__clone(pos);
> > + if (map->start > pos->map->start) {
> > + struct map *before = map__clone(pos->map);
> >
> > if (before == NULL) {
> > err = -ENOMEM;
> > @@ -280,14 +320,17 @@ int maps__fixup_overlappings(struct maps *maps, struct map *map, FILE *fp)
> > }
> >
> > before->end = map->start;
> > - __maps__insert(maps, before);
> > + err = __maps__insert(maps, before);
> > + if (err)
> > + goto put_map;
> > +
> > if (verbose >= 2 && !use_browser)
> > map__fprintf(before, fp);
> > map__put(before);
> > }
> >
> > - if (map->end < pos->end) {
> > - struct map *after = map__clone(pos);
> > + if (map->end < pos->map->end) {
> > + struct map *after = map__clone(pos->map);
> >
> > if (after == NULL) {
> > err = -ENOMEM;
> > @@ -295,15 +338,19 @@ int maps__fixup_overlappings(struct maps *maps, struct map *map, FILE *fp)
> > }
> >
> > after->start = map->end;
> > - after->pgoff += map->end - pos->start;
> > - assert(pos->map_ip(pos, map->end) == after->map_ip(after, map->end));
> > - __maps__insert(maps, after);
> > + after->pgoff += map->end - pos->map->start;
> > + assert(pos->map->map_ip(pos->map, map->end) ==
> > + after->map_ip(after, map->end));
> > + err = __maps__insert(maps, after);
> > + if (err)
> > + goto put_map;
> > +
> > if (verbose >= 2 && !use_browser)
> > map__fprintf(after, fp);
> > map__put(after);
> > }
> > put_map:
> > - map__put(pos);
> > + map__put(pos->map);
> >
> > if (err)
> > goto out;
> > @@ -322,12 +369,12 @@ int maps__clone(struct thread *thread, struct maps *parent)
> > {
> > struct maps *maps = thread->maps;
> > int err;
> > - struct map *map;
> > + struct map_rb_node *rb_node;
> >
> > down_read(&parent->lock);
> >
> > - maps__for_each_entry(parent, map) {
> > - struct map *new = map__clone(map);
> > + maps__for_each_entry(parent, rb_node) {
> > + struct map *new = map__clone(rb_node->map);
> >
> > if (new == NULL) {
> > err = -ENOMEM;
> > @@ -338,7 +385,10 @@ int maps__clone(struct thread *thread, struct maps *parent)
> > if (err)
> > goto out_unlock;
> >
> > - maps__insert(maps, new);
> > + err = maps__insert(maps, new);
> > + if (err)
> > + goto out_unlock;
> > +
> > map__put(new);
> > }
> >
> > @@ -348,40 +398,30 @@ int maps__clone(struct thread *thread, struct maps *parent)
> > return err;
> > }
> >
> > -static void __maps__insert(struct maps *maps, struct map *map)
> > +struct map_rb_node *maps__find_node(struct maps *maps, struct map *map)
> > {
> > - struct rb_node **p = &maps->entries.rb_node;
> > - struct rb_node *parent = NULL;
> > - const u64 ip = map->start;
> > - struct map *m;
> > + struct map_rb_node *rb_node;
> >
> > - while (*p != NULL) {
> > - parent = *p;
> > - m = rb_entry(parent, struct map, rb_node);
> > - if (ip < m->start)
> > - p = &(*p)->rb_left;
> > - else
> > - p = &(*p)->rb_right;
> > + maps__for_each_entry(maps, rb_node) {
> > + if (rb_node->map == map)
> > + return rb_node;
> > }
> > -
> > - rb_link_node(&map->rb_node, parent, p);
> > - rb_insert_color(&map->rb_node, &maps->entries);
> > - map__get(map);
> > + return NULL;
> > }
> >
> > struct map *maps__find(struct maps *maps, u64 ip)
> > {
> > struct rb_node *p;
> > - struct map *m;
> > + struct map_rb_node *m;
> >
> > down_read(&maps->lock);
> >
> > p = maps->entries.rb_node;
> > while (p != NULL) {
> > - m = rb_entry(p, struct map, rb_node);
> > - if (ip < m->start)
> > + m = rb_entry(p, struct map_rb_node, rb_node);
> > + if (ip < m->map->start)
> > p = p->rb_left;
> > - else if (ip >= m->end)
> > + else if (ip >= m->map->end)
> > p = p->rb_right;
> > else
> > goto out;
> > @@ -390,14 +430,30 @@ struct map *maps__find(struct maps *maps, u64 ip)
> > m = NULL;
> > out:
> > up_read(&maps->lock);
> > - return m;
> > +
> > + return m ? m->map : NULL;
> > }
> >
> > -struct map *maps__first(struct maps *maps)
> > +struct map_rb_node *maps__first(struct maps *maps)
> > {
> > struct rb_node *first = rb_first(&maps->entries);
> >
> > if (first)
> > - return rb_entry(first, struct map, rb_node);
> > + return rb_entry(first, struct map_rb_node, rb_node);
> > return NULL;
> > }
> > +
> > +struct map_rb_node *map_rb_node__next(struct map_rb_node *node)
> > +{
> > + struct rb_node *next;
> > +
> > + if (!node)
> > + return NULL;
> > +
> > + next = rb_next(&node->rb_node);
> > +
> > + if (!next)
> > + return NULL;
> > +
> > + return rb_entry(next, struct map_rb_node, rb_node);
> > +}
> > diff --git a/tools/perf/util/maps.h b/tools/perf/util/maps.h
> > index 7e729ff42749..512746ec0f9a 100644
> > --- a/tools/perf/util/maps.h
> > +++ b/tools/perf/util/maps.h
> > @@ -15,15 +15,22 @@ struct map;
> > struct maps;
> > struct thread;
> >
> > +struct map_rb_node {
> > + struct rb_node rb_node;
> > + struct map *map;
> > +};
> > +
> > +struct map_rb_node *maps__first(struct maps *maps);
> > +struct map_rb_node *map_rb_node__next(struct map_rb_node *node);
> > +struct map_rb_node *maps__find_node(struct maps *maps, struct map *map);
> > struct map *maps__find(struct maps *maps, u64 addr);
> > -struct map *maps__first(struct maps *maps);
> > -struct map *map__next(struct map *map);
> >
> > #define maps__for_each_entry(maps, map) \
> > - for (map = maps__first(maps); map; map = map__next(map))
> > + for (map = maps__first(maps); map; map = map_rb_node__next(map))
> >
> > #define maps__for_each_entry_safe(maps, map, next) \
> > - for (map = maps__first(maps), next = map__next(map); map; map = next, next = map__next(map))
> > + for (map = maps__first(maps), next = map_rb_node__next(map); map; \
> > + map = next, next = map_rb_node__next(map))
> >
> > struct maps {
> > struct rb_root entries;
> > @@ -63,7 +70,7 @@ void maps__put(struct maps *maps);
> > int maps__clone(struct thread *thread, struct maps *parent);
> > size_t maps__fprintf(struct maps *maps, FILE *fp);
> >
> > -void maps__insert(struct maps *maps, struct map *map);
> > +int maps__insert(struct maps *maps, struct map *map);
> >
> > void maps__remove(struct maps *maps, struct map *map);
> >
> > diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
> > index bc5ab782ace5..f9fbf611f2bf 100644
> > --- a/tools/perf/util/probe-event.c
> > +++ b/tools/perf/util/probe-event.c
> > @@ -150,23 +150,27 @@ static int kernel_get_symbol_address_by_name(const char *name, u64 *addr,
> > static struct map *kernel_get_module_map(const char *module)
> > {
> > struct maps *maps = machine__kernel_maps(host_machine);
> > - struct map *pos;
> > + struct map_rb_node *pos;
> >
> > /* A file path -- this is an offline module */
> > if (module && strchr(module, '/'))
> > return dso__new_map(module);
> >
> > if (!module) {
> > - pos = machine__kernel_map(host_machine);
> > - return map__get(pos);
> > + struct map *map = machine__kernel_map(host_machine);
> > +
> > + return map__get(map);
> > }
> >
> > maps__for_each_entry(maps, pos) {
> > /* short_name is "[module]" */
> > - if (strncmp(pos->dso->short_name + 1, module,
> > - pos->dso->short_name_len - 2) == 0 &&
> > - module[pos->dso->short_name_len - 2] == '\0') {
> > - return map__get(pos);
> > + const char *short_name = pos->map->dso->short_name;
> > + u16 short_name_len = pos->map->dso->short_name_len;
> > +
> > + if (strncmp(short_name + 1, module,
> > + short_name_len - 2) == 0 &&
> > + module[short_name_len - 2] == '\0') {
> > + return map__get(pos->map);
> > }
> > }
> > return NULL;
> > diff --git a/tools/perf/util/symbol-elf.c b/tools/perf/util/symbol-elf.c
> > index 31cd59a2b66e..4607c9438866 100644
> > --- a/tools/perf/util/symbol-elf.c
> > +++ b/tools/perf/util/symbol-elf.c
> > @@ -1000,10 +1000,14 @@ static int dso__process_kernel_symbol(struct dso *dso, struct map *map,
> > map->unmap_ip = map__unmap_ip;
> > /* Ensure maps are correctly ordered */
> > if (kmaps) {
> > + int err;
> > +
> > map__get(map);
> > maps__remove(kmaps, map);
> > - maps__insert(kmaps, map);
> > + err = maps__insert(kmaps, map);
> > map__put(map);
> > + if (err)
> > + return err;
> > }
> > }
> >
> > @@ -1056,7 +1060,8 @@ static int dso__process_kernel_symbol(struct dso *dso, struct map *map,
> > curr_map->map_ip = curr_map->unmap_ip = identity__map_ip;
> > }
> > curr_dso->symtab_type = dso->symtab_type;
> > - maps__insert(kmaps, curr_map);
> > + if (maps__insert(kmaps, curr_map))
> > + return -1;
> > /*
> > * Add it before we drop the reference to curr_map, i.e. while
> > * we still are sure to have a reference to this DSO via
> > diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
> > index 99accae7d3b8..266c65bb8bbb 100644
> > --- a/tools/perf/util/symbol.c
> > +++ b/tools/perf/util/symbol.c
> > @@ -247,13 +247,13 @@ void symbols__fixup_end(struct rb_root_cached *symbols)
> >
> > void maps__fixup_end(struct maps *maps)
> > {
> > - struct map *prev = NULL, *curr;
> > + struct map_rb_node *prev = NULL, *curr;
> >
> > down_write(&maps->lock);
> >
> > maps__for_each_entry(maps, curr) {
> > - if (prev != NULL && !prev->end)
> > - prev->end = curr->start;
> > + if (prev != NULL && !prev->map->end)
> > + prev->map->end = curr->map->start;
> >
> > prev = curr;
> > }
> > @@ -262,8 +262,8 @@ void maps__fixup_end(struct maps *maps)
> > * We still haven't the actual symbols, so guess the
> > * last map final address.
> > */
> > - if (curr && !curr->end)
> > - curr->end = ~0ULL;
> > + if (curr && !curr->map->end)
> > + curr->map->end = ~0ULL;
> >
> > up_write(&maps->lock);
> > }
> > @@ -911,7 +911,10 @@ static int maps__split_kallsyms(struct maps *kmaps, struct dso *dso, u64 delta,
> > }
> >
> > curr_map->map_ip = curr_map->unmap_ip = identity__map_ip;
> > - maps__insert(kmaps, curr_map);
> > + if (maps__insert(kmaps, curr_map)) {
> > + dso__put(ndso);
> > + return -1;
> > + }
> > ++kernel_range;
> > } else if (delta) {
> > /* Kernel was relocated at boot time */
> > @@ -1099,14 +1102,15 @@ int compare_proc_modules(const char *from, const char *to)
> > static int do_validate_kcore_modules(const char *filename, struct maps *kmaps)
> > {
> > struct rb_root modules = RB_ROOT;
> > - struct map *old_map;
> > + struct map_rb_node *old_node;
> > int err;
> >
> > err = read_proc_modules(filename, &modules);
> > if (err)
> > return err;
> >
> > - maps__for_each_entry(kmaps, old_map) {
> > + maps__for_each_entry(kmaps, old_node) {
> > + struct map *old_map = old_node->map;
> > struct module_info *mi;
> >
> > if (!__map__is_kmodule(old_map)) {
> > @@ -1224,10 +1228,13 @@ static int kcore_mapfn(u64 start, u64 len, u64 pgoff, void *data)
> > */
> > int maps__merge_in(struct maps *kmaps, struct map *new_map)
> > {
> > - struct map *old_map;
> > + struct map_rb_node *rb_node;
> > LIST_HEAD(merged);
> > + int err = 0;
> > +
> > + maps__for_each_entry(kmaps, rb_node) {
> > + struct map *old_map = rb_node->map;
> >
> > - maps__for_each_entry(kmaps, old_map) {
> > /* no overload with this one */
> > if (new_map->end < old_map->start ||
> > new_map->start >= old_map->end)
> > @@ -1252,13 +1259,16 @@ int maps__merge_in(struct maps *kmaps, struct map *new_map)
> > struct map_list_node *m;
> >
> > m = malloc(sizeof(*m));
> > - if (!m)
> > - return -ENOMEM;
> > + if (!m) {
> > + err = -ENOMEM;
> > + goto out;
> > + }
> >
> > m->map = map__clone(new_map);
> > if (!m->map) {
> > free(m);
> > - return -ENOMEM;
> > + err = -ENOMEM;
> > + goto out;
> > }
> >
> > m->map->end = old_map->start;
> > @@ -1290,21 +1300,24 @@ int maps__merge_in(struct maps *kmaps, struct map *new_map)
> > }
> > }
> >
> > +out:
> > while (!list_empty(&merged)) {
> > struct map_list_node *old_node;
> >
> > old_node = list_entry(merged.next, struct map_list_node, node);
> > list_del_init(&old_node->node);
> > - maps__insert(kmaps, old_node->map);
> > + if (!err)
> > + err = maps__insert(kmaps, old_node->map);
> > map__put(old_node->map);
> > free(old_node);
> > }
> >
> > if (new_map) {
> > - maps__insert(kmaps, new_map);
> > + if (!err)
> > + err = maps__insert(kmaps, new_map);
> > map__put(new_map);
> > }
> > - return 0;
> > + return err;
> > }
> >
> > static int dso__load_kcore(struct dso *dso, struct map *map,
> > @@ -1312,7 +1325,8 @@ static int dso__load_kcore(struct dso *dso, struct map *map,
> > {
> > struct maps *kmaps = map__kmaps(map);
> > struct kcore_mapfn_data md;
> > - struct map *old_map, *replacement_map = NULL, *next;
> > + struct map *replacement_map = NULL;
> > + struct map_rb_node *old_node, *next;
> > struct machine *machine;
> > bool is_64_bit;
> > int err, fd;
> > @@ -1359,7 +1373,9 @@ static int dso__load_kcore(struct dso *dso, struct map *map,
> > }
> >
> > /* Remove old maps */
> > - maps__for_each_entry_safe(kmaps, old_map, next) {
> > + maps__for_each_entry_safe(kmaps, old_node, next) {
> > + struct map *old_map = old_node->map;
> > +
> > /*
> > * We need to preserve eBPF maps even if they are
> > * covered by kcore, because we need to access
> > @@ -1400,17 +1416,21 @@ static int dso__load_kcore(struct dso *dso, struct map *map,
> > /* Ensure maps are correctly ordered */
> > map__get(map);
> > maps__remove(kmaps, map);
> > - maps__insert(kmaps, map);
> > + err = maps__insert(kmaps, map);
> > map__put(map);
> > map__put(new_node->map);
> > + if (err)
> > + goto out_err;
> > } else {
> > /*
> > * Merge kcore map into existing maps,
> > * and ensure that current maps (eBPF)
> > * stay intact.
> > */
> > - if (maps__merge_in(kmaps, new_node->map))
> > + if (maps__merge_in(kmaps, new_node->map)) {
> > + err = -EINVAL;
> > goto out_err;
> > + }
> > }
> > free(new_node);
> > }
> > @@ -1457,7 +1477,7 @@ static int dso__load_kcore(struct dso *dso, struct map *map,
> > free(list_node);
> > }
> > close(fd);
> > - return -EINVAL;
> > + return err;
> > }
> >
> > /*
> > @@ -1991,8 +2011,9 @@ void __maps__sort_by_name(struct maps *maps)
> >
> > static int map__groups__sort_by_name_from_rbtree(struct maps *maps)
> > {
> > - struct map *map;
> > - struct map **maps_by_name = realloc(maps->maps_by_name, maps->nr_maps * sizeof(map));
> > + struct map_rb_node *rb_node;
> > + struct map **maps_by_name = realloc(maps->maps_by_name,
> > + maps->nr_maps * sizeof(struct map *));
> > int i = 0;
> >
> > if (maps_by_name == NULL)
> > @@ -2001,8 +2022,8 @@ static int map__groups__sort_by_name_from_rbtree(struct maps *maps)
> > maps->maps_by_name = maps_by_name;
> > maps->nr_maps_allocated = maps->nr_maps;
> >
> > - maps__for_each_entry(maps, map)
> > - maps_by_name[i++] = map;
> > + maps__for_each_entry(maps, rb_node)
> > + maps_by_name[i++] = rb_node->map;
> >
> > __maps__sort_by_name(maps);
> > return 0;
> > @@ -2024,6 +2045,7 @@ static struct map *__maps__find_by_name(struct maps *maps, const char *name)
> >
> > struct map *maps__find_by_name(struct maps *maps, const char *name)
> > {
> > + struct map_rb_node *rb_node;
> > struct map *map;
> >
> > down_read(&maps->lock);
> > @@ -2042,12 +2064,13 @@ struct map *maps__find_by_name(struct maps *maps, const char *name)
> > goto out_unlock;
> >
> > /* Fallback to traversing the rbtree... */
> > - maps__for_each_entry(maps, map)
> > + maps__for_each_entry(maps, rb_node) {
> > + map = rb_node->map;
> > if (strcmp(map->dso->short_name, name) == 0) {
> > maps->last_search_by_name = map;
> > goto out_unlock;
> > }
> > -
> > + }
> > map = NULL;
> >
> > out_unlock:
> > diff --git a/tools/perf/util/synthetic-events.c b/tools/perf/util/synthetic-events.c
> > index 70f095624a0b..ed2d55d224aa 100644
> > --- a/tools/perf/util/synthetic-events.c
> > +++ b/tools/perf/util/synthetic-events.c
> > @@ -639,7 +639,7 @@ int perf_event__synthesize_modules(struct perf_tool *tool, perf_event__handler_t
> > struct machine *machine)
> > {
> > int rc = 0;
> > - struct map *pos;
> > + struct map_rb_node *pos;
> > struct maps *maps = machine__kernel_maps(machine);
> > union perf_event *event;
> > size_t size = symbol_conf.buildid_mmap2 ?
> > @@ -662,37 +662,39 @@ int perf_event__synthesize_modules(struct perf_tool *tool, perf_event__handler_t
> > event->header.misc = PERF_RECORD_MISC_GUEST_KERNEL;
> >
> > maps__for_each_entry(maps, pos) {
> > - if (!__map__is_kmodule(pos))
> > + struct map *map = pos->map;
> > +
> > + if (!__map__is_kmodule(map))
> > continue;
> >
> > if (symbol_conf.buildid_mmap2) {
> > - size = PERF_ALIGN(pos->dso->long_name_len + 1, sizeof(u64));
> > + size = PERF_ALIGN(map->dso->long_name_len + 1, sizeof(u64));
> > event->mmap2.header.type = PERF_RECORD_MMAP2;
> > event->mmap2.header.size = (sizeof(event->mmap2) -
> > (sizeof(event->mmap2.filename) - size));
> > memset(event->mmap2.filename + size, 0, machine->id_hdr_size);
> > event->mmap2.header.size += machine->id_hdr_size;
> > - event->mmap2.start = pos->start;
> > - event->mmap2.len = pos->end - pos->start;
> > + event->mmap2.start = map->start;
> > + event->mmap2.len = map->end - map->start;
> > event->mmap2.pid = machine->pid;
> >
> > - memcpy(event->mmap2.filename, pos->dso->long_name,
> > - pos->dso->long_name_len + 1);
> > + memcpy(event->mmap2.filename, map->dso->long_name,
> > + map->dso->long_name_len + 1);
> >
> > perf_record_mmap2__read_build_id(&event->mmap2, false);
> > } else {
> > - size = PERF_ALIGN(pos->dso->long_name_len + 1, sizeof(u64));
> > + size = PERF_ALIGN(map->dso->long_name_len + 1, sizeof(u64));
> > event->mmap.header.type = PERF_RECORD_MMAP;
> > event->mmap.header.size = (sizeof(event->mmap) -
> > (sizeof(event->mmap.filename) - size));
> > memset(event->mmap.filename + size, 0, machine->id_hdr_size);
> > event->mmap.header.size += machine->id_hdr_size;
> > - event->mmap.start = pos->start;
> > - event->mmap.len = pos->end - pos->start;
> > + event->mmap.start = map->start;
> > + event->mmap.len = map->end - map->start;
> > event->mmap.pid = machine->pid;
> >
> > - memcpy(event->mmap.filename, pos->dso->long_name,
> > - pos->dso->long_name_len + 1);
> > + memcpy(event->mmap.filename, map->dso->long_name,
> > + map->dso->long_name_len + 1);
> > }
> >
> > if (perf_tool__process_synth_event(tool, event, machine, process) != 0) {
> > diff --git a/tools/perf/util/thread.c b/tools/perf/util/thread.c
> > index 665e5c0618ed..4baf4db8af65 100644
> > --- a/tools/perf/util/thread.c
> > +++ b/tools/perf/util/thread.c
> > @@ -338,9 +338,7 @@ int thread__insert_map(struct thread *thread, struct map *map)
> > return ret;
> >
> > maps__fixup_overlappings(thread->maps, map, stderr);
> > - maps__insert(thread->maps, map);
> > -
> > - return 0;
> > + return maps__insert(thread->maps, map);
> > }
> >
> > static int __thread__prepare_access(struct thread *thread)
> > @@ -348,12 +346,12 @@ static int __thread__prepare_access(struct thread *thread)
> > bool initialized = false;
> > int err = 0;
> > struct maps *maps = thread->maps;
> > - struct map *map;
> > + struct map_rb_node *rb_node;
> >
> > down_read(&maps->lock);
> >
> > - maps__for_each_entry(maps, map) {
> > - err = unwind__prepare_access(thread->maps, map, &initialized);
> > + maps__for_each_entry(maps, rb_node) {
> > + err = unwind__prepare_access(thread->maps, rb_node->map, &initialized);
> > if (err || initialized)
> > break;
> > }
> > diff --git a/tools/perf/util/vdso.c b/tools/perf/util/vdso.c
> > index 43beb169631d..835c39efb80d 100644
> > --- a/tools/perf/util/vdso.c
> > +++ b/tools/perf/util/vdso.c
> > @@ -144,10 +144,11 @@ static enum dso_type machine__thread_dso_type(struct machine *machine,
> > struct thread *thread)
> > {
> > enum dso_type dso_type = DSO__TYPE_UNKNOWN;
> > - struct map *map;
> > + struct map_rb_node *rb_node;
> > +
> > + maps__for_each_entry(thread->maps, rb_node) {
> > + struct dso *dso = rb_node->map->dso;
> >
> > - maps__for_each_entry(thread->maps, map) {
> > - struct dso *dso = map->dso;
> > if (!dso || dso->long_name[0] != '/')
> > continue;
> > dso_type = dso__type(dso, machine);
> > --
> > 2.35.1.265.g69c8d7142f-goog
>
> --
>
> - Arnaldo