From 8afcc19fbf083a8459284d9a29b4b5ac1cb2396c Mon Sep 17 00:00:00 2001 From: Florent Revest Date: Mon, 17 May 2021 11:28:29 +0200 Subject: bpf: Clarify a bpf_bprintf_prepare macro The per-cpu buffers contain bprintf data rather than printf arguments. The macro name and comment were a bit confusing, this rewords them in a clearer way. Signed-off-by: Florent Revest Signed-off-by: Daniel Borkmann Acked-by: Song Liu Link: https://lore.kernel.org/bpf/20210517092830.1026418-1-revest@chromium.org --- kernel/bpf/helpers.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) (limited to 'kernel') diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c index ef658a9ea5c9..3a5ab614cbb0 100644 --- a/kernel/bpf/helpers.c +++ b/kernel/bpf/helpers.c @@ -692,13 +692,14 @@ static int bpf_trace_copy_string(char *buf, void *unsafe_ptr, char fmt_ptype, return -EINVAL; } -/* Per-cpu temp buffers which can be used by printf-like helpers for %s or %p +/* Per-cpu temp buffers used by printf-like helpers to store the bprintf binary + * arguments representation. */ -#define MAX_PRINTF_BUF_LEN 512 +#define MAX_BPRINTF_BUF_LEN 512 /* Support executing three nested bprintf helper calls on a given CPU */ struct bpf_bprintf_buffers { - char tmp_bufs[3][MAX_PRINTF_BUF_LEN]; + char tmp_bufs[3][MAX_BPRINTF_BUF_LEN]; }; static DEFINE_PER_CPU(struct bpf_bprintf_buffers, bpf_bprintf_bufs); static DEFINE_PER_CPU(int, bpf_bprintf_nest_level); @@ -761,7 +762,7 @@ int bpf_bprintf_prepare(char *fmt, u32 fmt_size, const u64 *raw_args, if (num_args && try_get_fmt_tmp_buf(&tmp_buf)) return -EBUSY; - tmp_buf_end = tmp_buf + MAX_PRINTF_BUF_LEN; + tmp_buf_end = tmp_buf + MAX_BPRINTF_BUF_LEN; *bin_args = (u32 *)tmp_buf; } -- cgit v1.2.3