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=-13.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 A62E8C433B4 for ; Sat, 3 Apr 2021 14:34:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 856D261278 for ; Sat, 3 Apr 2021 14:34:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236793AbhDCOeq (ORCPT ); Sat, 3 Apr 2021 10:34:46 -0400 Received: from mail.kernel.org ([198.145.29.99]:52464 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236621AbhDCOef (ORCPT ); Sat, 3 Apr 2021 10:34:35 -0400 Received: from gandalf.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 0CE2761279; Sat, 3 Apr 2021 14:34:33 +0000 (UTC) Received: from rostedt by gandalf.local.home with local (Exim 4.94) (envelope-from ) id 1lShM8-0040GN-3H; Sat, 03 Apr 2021 10:34:32 -0400 Message-ID: <20210403143431.982491171@goodmis.org> User-Agent: quilt/0.66 Date: Sat, 03 Apr 2021 10:33:51 -0400 From: Steven Rostedt To: linux-kernel@vger.kernel.org Cc: Ingo Molnar , Andrew Morton , Linus Torvalds Subject: [for-next][PATCH 4/4] ftrace: Simplify the calculation of page number for ftrace_page->records some more References: <20210403143347.409590683@goodmis.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: "Steven Rostedt (VMware)" Commit b40c6eabfcd40 ("ftrace: Simplify the calculation of page number for ftrace_page->records") simplified the calculation of the number of pages needed for each page group without having any empty pages, but it can be simplified even further. Link: https://lore.kernel.org/lkml/CAHk-=wjt9b7kxQ2J=aDNKbR1QBMB3Hiqb_hYcZbKsxGRSEb+gQ@mail.gmail.com/ Suggested-by: Linus Torvalds Signed-off-by: Steven Rostedt (VMware) --- kernel/trace/ftrace.c | 10 ++-------- 1 file changed, 2 insertions(+), 8 deletions(-) diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index f7bef5a9ada9..057e962ca5ce 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -3156,15 +3156,9 @@ static int ftrace_allocate_records(struct ftrace_page *pg, int count) if (WARN_ON(!count)) return -EINVAL; + /* We want to fill as much as possible, with no empty pages */ pages = DIV_ROUND_UP(count, ENTRIES_PER_PAGE); - order = get_count_order(pages); - - /* - * We want to fill as much as possible. No more than a page - * may be empty. - */ - if (!is_power_of_2(pages)) - order--; + order = fls(pages) - 1; again: pg->records = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, order); -- 2.30.1