From e1f5bb18a7b25cac6cbf219b5f28159656faa152 Mon Sep 17 00:00:00 2001 From: Namhyung Kim Date: Thu, 6 Mar 2025 22:12:50 -0800 Subject: [PATCH] perf report: Fix memory leaks in the hierarchy mode Ian told me that there are many memory leaks in the hierarchy mode. I can easily reproduce it with the follwing command. $ make DEBUG=1 EXTRA_CFLAGS=-fsanitize=leak $ perf record --latency -g -- ./perf test -w thloop $ perf report -H --stdio ... Indirect leak of 168 byte(s) in 21 object(s) allocated from: #0 0x7f3414c16c65 in malloc ../../../../src/libsanitizer/lsan/lsan_interceptors.cpp:75 #1 0x55ed3602346e in map__get util/map.h:189 #2 0x55ed36024cc4 in hist_entry__init util/hist.c:476 #3 0x55ed36025208 in hist_entry__new util/hist.c:588 #4 0x55ed36027c05 in hierarchy_insert_entry util/hist.c:1587 #5 0x55ed36027e2e in hists__hierarchy_insert_entry util/hist.c:1638 #6 0x55ed36027fa4 in hists__collapse_insert_entry util/hist.c:1685 #7 0x55ed360283e8 in hists__collapse_resort util/hist.c:1776 #8 0x55ed35de0323 in report__collapse_hists /home/namhyung/project/linux/tools/perf/builtin-report.c:735 #9 0x55ed35de15b4 in __cmd_report /home/namhyung/project/linux/tools/perf/builtin-report.c:1119 #10 0x55ed35de43dc in cmd_report /home/namhyung/project/linux/tools/perf/builtin-report.c:1867 #11 0x55ed35e66767 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:351 #12 0x55ed35e66a0e in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:404 #13 0x55ed35e66b67 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:448 #14 0x55ed35e66eb0 in main /home/namhyung/project/linux/tools/perf/perf.c:556 #15 0x7f340ac33d67 in __libc_start_call_main ../sysdeps/nptl/libc_start_call_main.h:58 ... $ perf report -H --stdio 2>&1 | grep -c '^Indirect leak' 93 I found that hist_entry__delete() missed to release child entries in the hierarchy tree (hroot_{in,out}). It needs to iterate the child entries and call hist_entry__delete() recursively. After this change: $ perf report -H --stdio 2>&1 | grep -c '^Indirect leak' 0 Reported-by: Ian Rogers Tested-by Thomas Falcon Reviewed-by: Ian Rogers Link: https://lore.kernel.org/r/20250307061250.320849-2-namhyung@kernel.org Signed-off-by: Namhyung Kim --- tools/perf/util/hist.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/tools/perf/util/hist.c b/tools/perf/util/hist.c index fbf131aeae7f..d65228c11412 100644 --- a/tools/perf/util/hist.c +++ b/tools/perf/util/hist.c @@ -1385,6 +1385,16 @@ void hist_entry__delete(struct hist_entry *he) { struct hist_entry_ops *ops = he->ops; + if (symbol_conf.report_hierarchy) { + struct rb_root *root = &he->hroot_out.rb_root; + struct hist_entry *child, *tmp; + + rbtree_postorder_for_each_entry_safe(child, tmp, root, rb_node) + hist_entry__delete(child); + + *root = RB_ROOT; + } + thread__zput(he->thread); map_symbol__exit(&he->ms);