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| author | Tianyi Liu <i.pear@outlook.com> | 2022-09-28 11:09:32 +0300 |
|---|---|---|
| committer | Andrii Nakryiko <andrii@kernel.org> | 2022-10-01 01:40:46 +0300 |
| commit | 3ca2fb497440a3c8294f9df0ce7b2c3c9a1c5875 (patch) | |
| tree | 7ef24febc2a8323e03331e137d3b42c9ded065d8 /tools/bpf/bpftool/map_perf_ring.c | |
| parent | 51e05a8cf8eb34da7473823b7f236a77adfef0b4 (diff) | |
| download | linux-3ca2fb497440a3c8294f9df0ce7b2c3c9a1c5875.tar.xz | |
bpftool: Fix error message of strerror
strerror() expects a positive errno, however variable err will never be
positive when an error occurs. This causes bpftool to output too many
"unknown error", even a simple "file not exist" error can not get an
accurate message.
This patch fixed all "strerror(err)" patterns in bpftool.
Specially in btf.c#L823, hashmap__append() is an internal function of
libbpf and will not change errno, so there's a little difference.
Some libbpf_get_error() calls are kept for return values.
Changes since v1: https://lore.kernel.org/bpf/SY4P282MB1084B61CD8671DFA395AA8579D539@SY4P282MB1084.AUSP282.PROD.OUTLOOK.COM/
Check directly for NULL values instead of calling libbpf_get_error().
Signed-off-by: Tianyi Liu <i.pear@outlook.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/SY4P282MB1084AD9CD84A920F08DF83E29D549@SY4P282MB1084.AUSP282.PROD.OUTLOOK.COM
Diffstat (limited to 'tools/bpf/bpftool/map_perf_ring.c')
| -rw-r--r-- | tools/bpf/bpftool/map_perf_ring.c | 7 |
1 files changed, 3 insertions, 4 deletions
diff --git a/tools/bpf/bpftool/map_perf_ring.c b/tools/bpf/bpftool/map_perf_ring.c index 1583281d1327..21d7d447e1f3 100644 --- a/tools/bpf/bpftool/map_perf_ring.c +++ b/tools/bpf/bpftool/map_perf_ring.c @@ -188,10 +188,9 @@ int do_event_pipe(int argc, char **argv) opts.map_keys = &ctx.idx; pb = perf_buffer__new_raw(map_fd, MMAP_PAGE_CNT, &perf_attr, print_bpf_output, &ctx, &opts); - err = libbpf_get_error(pb); - if (err) { + if (!pb) { p_err("failed to create perf buffer: %s (%d)", - strerror(err), err); + strerror(errno), errno); goto err_close_map; } @@ -206,7 +205,7 @@ int do_event_pipe(int argc, char **argv) err = perf_buffer__poll(pb, 200); if (err < 0 && err != -EINTR) { p_err("perf buffer polling failed: %s (%d)", - strerror(err), err); + strerror(errno), errno); goto err_close_pb; } } |