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=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS autolearn=ham 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 CF3DFC43381 for ; Tue, 26 Mar 2019 01:36:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A3EF92083D for ; Tue, 26 Mar 2019 01:36:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730675AbfCZBgK (ORCPT ); Mon, 25 Mar 2019 21:36:10 -0400 Received: from mail.kernel.org ([198.145.29.99]:38344 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727412AbfCZBgK (ORCPT ); Mon, 25 Mar 2019 21:36:10 -0400 Received: from oasis.local.home (cpe-66-24-58-225.stny.res.rr.com [66.24.58.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 3C8BC2075D; Tue, 26 Mar 2019 01:36:09 +0000 (UTC) Date: Mon, 25 Mar 2019 21:36:07 -0400 From: Steven Rostedt To: YueHaibing Cc: Ingo Molnar , , Subject: Re: [PATCH -next] ring-buffer: Fix ring buffer size in rb_write_something Message-ID: <20190325213607.74a62138@oasis.local.home> In-Reply-To: <1537704693-184237-1-git-send-email-yuehaibing@huawei.com> References: <1537704693-184237-1-git-send-email-yuehaibing@huawei.com> X-Mailer: Claws Mail 3.17.3 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, 23 Sep 2018 12:11:33 +0000 YueHaibing wrote: > 'cnt' should be used to calculate ring buffer size rather than data->cnt I just found this patch in my inbox (was traveling at the time. But now I have patchwork attached to my INBOX so patches like these shouldn't be missed anymore!) Yes, you are correct, this should be fixed. But as it is just for a startup test, I'll queue it for the next merge window. Thanks and sorry for the delay. -- Steve > > Signed-off-by: YueHaibing > --- > kernel/trace/ring_buffer.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c > index 65bd461..53538c3 100644 > --- a/kernel/trace/ring_buffer.c > +++ b/kernel/trace/ring_buffer.c > @@ -4924,7 +4924,7 @@ static __init int rb_write_something(struct > rb_test_data *data, bool nested) cnt = data->cnt + (nested ? 27 : 0); > > /* Multiply cnt by ~e, to make some unique increment */ > - size = (data->cnt * 68 / 25) % (sizeof(rb_string) - 1); > + size = (cnt * 68 / 25) % (sizeof(rb_string) - 1); > > len = size + sizeof(struct rb_item); > > >