6.10-stable review patch. If anyone has any objections, please let me know.
------------------
From: Ian Rogers irogers@google.com
[ Upstream commit 599c19397b17d197fc1184bbc950f163a292efc9 ]
The 'struct callchain_cursor_node' has a 'struct map_symbol' whose maps and map members are reference counted. Ensure these values use a _get routine to increment the reference counts and use map_symbol__exit() to release the reference counts.
Do similar for 'struct thread's prev_lbr_cursor, but save the size of the prev_lbr_cursor array so that it may be iterated.
Ensure that when stitch_nodes are placed on the free list the map_symbols are exited.
Fix resolve_lbr_callchain_sample() by replacing list_replace_init() to list_splice_init(), so the whole list is moved and nodes aren't leaked.
A reproduction of the memory leaks is possible with a leak sanitizer build in the perf report command of:
``` $ perf record -e cycles --call-graph lbr perf test -w thloop $ perf report --stitch-lbr ```
Reviewed-by: Kan Liang kan.liang@linux.intel.com Fixes: ff165628d72644e3 ("perf callchain: Stitch LBR call stack") Signed-off-by: Ian Rogers irogers@google.com [ Basic tests after applying the patch, repeating the example above ] Tested-by: Arnaldo Carvalho de Melo acme@redhat.com Cc: Adrian Hunter adrian.hunter@intel.com Cc: Alexander Shishkin alexander.shishkin@linux.intel.com Cc: Andi Kleen ak@linux.intel.com Cc: Anne Macedo retpolanne@posteo.net Cc: Changbin Du changbin.du@huawei.com Cc: Ingo Molnar mingo@redhat.com Cc: Jiri Olsa jolsa@kernel.org Cc: Mark Rutland mark.rutland@arm.com Cc: Namhyung Kim namhyung@kernel.org Cc: Peter Zijlstra peterz@infradead.org Link: https://lore.kernel.org/r/20240808054644.1286065-1-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo acme@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- tools/perf/util/machine.c | 17 +++++++++++++++-- tools/perf/util/thread.c | 4 ++++ tools/perf/util/thread.h | 1 + 3 files changed, 20 insertions(+), 2 deletions(-)
diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c index 8477edefc2997..706be5e4a0761 100644 --- a/tools/perf/util/machine.c +++ b/tools/perf/util/machine.c @@ -2270,8 +2270,12 @@ static void save_lbr_cursor_node(struct thread *thread, cursor->curr = cursor->first; else cursor->curr = cursor->curr->next; + + map_symbol__exit(&lbr_stitch->prev_lbr_cursor[idx].ms); memcpy(&lbr_stitch->prev_lbr_cursor[idx], cursor->curr, sizeof(struct callchain_cursor_node)); + lbr_stitch->prev_lbr_cursor[idx].ms.maps = maps__get(cursor->curr->ms.maps); + lbr_stitch->prev_lbr_cursor[idx].ms.map = map__get(cursor->curr->ms.map);
lbr_stitch->prev_lbr_cursor[idx].valid = true; cursor->pos++; @@ -2482,6 +2486,9 @@ static bool has_stitched_lbr(struct thread *thread, memcpy(&stitch_node->cursor, &lbr_stitch->prev_lbr_cursor[i], sizeof(struct callchain_cursor_node));
+ stitch_node->cursor.ms.maps = maps__get(lbr_stitch->prev_lbr_cursor[i].ms.maps); + stitch_node->cursor.ms.map = map__get(lbr_stitch->prev_lbr_cursor[i].ms.map); + if (callee) list_add(&stitch_node->node, &lbr_stitch->lists); else @@ -2505,6 +2512,8 @@ static bool alloc_lbr_stitch(struct thread *thread, unsigned int max_lbr) if (!thread__lbr_stitch(thread)->prev_lbr_cursor) goto free_lbr_stitch;
+ thread__lbr_stitch(thread)->prev_lbr_cursor_size = max_lbr + 1; + INIT_LIST_HEAD(&thread__lbr_stitch(thread)->lists); INIT_LIST_HEAD(&thread__lbr_stitch(thread)->free_lists);
@@ -2560,8 +2569,12 @@ static int resolve_lbr_callchain_sample(struct thread *thread, max_lbr, callee);
if (!stitched_lbr && !list_empty(&lbr_stitch->lists)) { - list_replace_init(&lbr_stitch->lists, - &lbr_stitch->free_lists); + struct stitch_list *stitch_node; + + list_for_each_entry(stitch_node, &lbr_stitch->lists, node) + map_symbol__exit(&stitch_node->cursor.ms); + + list_splice_init(&lbr_stitch->lists, &lbr_stitch->free_lists); } memcpy(&lbr_stitch->prev_sample, sample, sizeof(*sample)); } diff --git a/tools/perf/util/thread.c b/tools/perf/util/thread.c index 87c59aa9fe38b..0ffdd52d86d70 100644 --- a/tools/perf/util/thread.c +++ b/tools/perf/util/thread.c @@ -476,6 +476,7 @@ void thread__free_stitch_list(struct thread *thread) return;
list_for_each_entry_safe(pos, tmp, &lbr_stitch->lists, node) { + map_symbol__exit(&pos->cursor.ms); list_del_init(&pos->node); free(pos); } @@ -485,6 +486,9 @@ void thread__free_stitch_list(struct thread *thread) free(pos); }
+ for (unsigned int i = 0 ; i < lbr_stitch->prev_lbr_cursor_size; i++) + map_symbol__exit(&lbr_stitch->prev_lbr_cursor[i].ms); + zfree(&lbr_stitch->prev_lbr_cursor); free(thread__lbr_stitch(thread)); thread__set_lbr_stitch(thread, NULL); diff --git a/tools/perf/util/thread.h b/tools/perf/util/thread.h index 8b4a3c69bad19..6cbf6eb2812e0 100644 --- a/tools/perf/util/thread.h +++ b/tools/perf/util/thread.h @@ -26,6 +26,7 @@ struct lbr_stitch { struct list_head free_lists; struct perf_sample prev_sample; struct callchain_cursor_node *prev_lbr_cursor; + unsigned int prev_lbr_cursor_size; };
DECLARE_RC_STRUCT(thread) {