diff options
author | Yafang Shao <laoar.shao@gmail.com> | 2023-08-30 03:03:25 +0000 |
---|---|---|
committer | Daniel Borkmann <daniel@iogearbox.net> | 2023-08-30 08:39:00 +0200 |
commit | 6a8faf10709161e7138202a8cf052b070971239f (patch) | |
tree | 14ccf85023822ef62c03ef2b7282d04d787b6322 /tools | |
parent | 32337c0a28242f725c2c499c15100d67a4133050 (diff) |
bpftool: Fix build warnings with -Wtype-limits
Quentin reported build warnings when building bpftool :
link.c: In function ‘perf_config_hw_cache_str’:
link.c:86:18: warning: comparison of unsigned expression in ‘>= 0’ is always true [-Wtype-limits]
86 | if ((id) >= 0 && (id) < ARRAY_SIZE(array)) \
| ^~
link.c:320:20: note: in expansion of macro ‘perf_event_name’
320 | hw_cache = perf_event_name(evsel__hw_cache, config & 0xff);
| ^~~~~~~~~~~~~~~
[... more of the same for the other calls to perf_event_name ...]
He also pointed out the reason and the solution:
We're always passing unsigned, so it should be safe to drop the check on
(id) >= 0.
Fixes: 62b57e3ddd64 ("bpftool: Add perf event names")
Reported-by: Quentin Monnet <quentin@isovalent.com>
Suggested-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Quentin Monnet <quentin@isovalent.com>
Closes: https://lore.kernel.org/bpf/a35d9a2d-54a0-49ec-9ed1-8fcf1369d3cc@isovalent.com
Link: https://lore.kernel.org/bpf/20230830030325.3786-1-laoar.shao@gmail.com
Diffstat (limited to 'tools')
-rw-r--r-- | tools/bpf/bpftool/link.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/tools/bpf/bpftool/link.c b/tools/bpf/bpftool/link.c index 0b214f6ab5c8..2e5c231e08ac 100644 --- a/tools/bpf/bpftool/link.c +++ b/tools/bpf/bpftool/link.c @@ -83,7 +83,7 @@ const char *evsel__hw_cache_result[PERF_COUNT_HW_CACHE_RESULT_MAX] = { #define perf_event_name(array, id) ({ \ const char *event_str = NULL; \ \ - if ((id) >= 0 && (id) < ARRAY_SIZE(array)) \ + if ((id) < ARRAY_SIZE(array)) \ event_str = array[id]; \ event_str; \ }) |