From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 85E61C433B4 for ; Mon, 17 May 2021 17:54:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5DC94610CD for ; Mon, 17 May 2021 17:54:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236741AbhEQR4D (ORCPT ); Mon, 17 May 2021 13:56:03 -0400 Received: from mail.kernel.org ([198.145.29.99]:32794 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236840AbhEQRz5 (ORCPT ); Mon, 17 May 2021 13:55:57 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 5A1F26108D; Mon, 17 May 2021 17:54:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1621274081; bh=jiEeCtCrsDMF9QllnOiUbRVpV9taErAhHTbDHtEG7QU=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=OwaMs+nU5kR1JYU5rzaty4sUIKE1xtd5O4qGk/r6SfH5ZYwdn/mDD9Klwl7ANoy9z RSJhuW0PN3io710gZvQ1tPSPxKCeVFKwDhq8CC4RmwjSq7a3eRuGfd/IS5t9ceUqxs 0W5+RXf2G8ITSTaSGZY1udqbNkrjNGQ+frn20KWGiK/bWJXsYwBjGXO/8rHOERaMe1 bNlliNAtvt43ow57pwGvwuhqanWRedtf6wu69/WenY/961j/kKRYNvVPjXUm4hjkGp HYPFQx1riZ7TBkDaw7b6plXvQG3SjIkeDUjTiTINDM6IqC4kBTzFpUZiyJBsa/Cf9t KP/GHQsObd9vg== Received: by mail-lj1-f172.google.com with SMTP id e2so1990495ljk.4; Mon, 17 May 2021 10:54:41 -0700 (PDT) X-Gm-Message-State: AOAM533kyBaqgaIRzgKQNd5+j6WzBnePQN/FaSwYVu7dnovXRCRYT/NN nMouGhohOTCKaYcCNt1QwHX2EG6PTB2Rw/MnbtU= X-Google-Smtp-Source: ABdhPJxzwjY9y7VK+QK3QovMADJ8au82rWOcutY7OHv0i3qPCx0ccVe6D16Ewmt8+2WakK1+AdSOthv0yOr8AVBldNk= X-Received: by 2002:a05:651c:39d:: with SMTP id e29mr489160ljp.97.1621274079735; Mon, 17 May 2021 10:54:39 -0700 (PDT) MIME-Version: 1.0 References: <20210517092830.1026418-1-revest@chromium.org> In-Reply-To: <20210517092830.1026418-1-revest@chromium.org> From: Song Liu Date: Mon, 17 May 2021 10:54:28 -0700 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH bpf 1/2] bpf: Clarify a bpf_bprintf_prepare macro To: Florent Revest Cc: bpf , Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , KP Singh , jackmanb@google.com, open list Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, May 17, 2021 at 2:29 AM Florent Revest wrote: > > 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 Acked-by: Song Liu > --- > kernel/bpf/helpers.c | 9 +++++---- > 1 file changed, 5 insertions(+), 4 deletions(-) > > 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; > } > > -- > 2.31.1.751.gd2f1c929bd-goog >