From patchwork Fri Mar 4 15:19:54 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Peter Zijlstra X-Patchwork-Id: 549197 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 59345C433EF for ; Fri, 4 Mar 2022 15:22:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240251AbiCDPXW (ORCPT ); Fri, 4 Mar 2022 10:23:22 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37778 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240225AbiCDPXR (ORCPT ); Fri, 4 Mar 2022 10:23:17 -0500 Received: from desiato.infradead.org (desiato.infradead.org [IPv6:2001:8b0:10b:1:d65d:64ff:fe57:4e05]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6FADB113A; Fri, 4 Mar 2022 07:22:28 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=Content-Type:MIME-Version:References: Subject:Cc:To:From:Date:Message-ID:Sender:Reply-To:Content-Transfer-Encoding: Content-ID:Content-Description:In-Reply-To; bh=i3uMN0XPCwzCCdJutSxOT0wu27OyMGNYJIeJECgEmYE=; b=aYtGzYmw8n0hqlGzMB/GVKRc1k 0EUx7uJQPV8vHY0UYk/h/Dl3Dg+B1v2+sZ/pD2d9O5516+8E88oq/iLMFb+HA7CRpXaUouUq0vHzr lCXCMP+xWspJSRaqVgpXv/YURR0YI998jQ+0JI6PyuyGv9QwRX1TTUuxvPE9P8Dj3M9Lr7ZVTxZ76 Ei0UbSwKFAg27eutVG9tJQzaC5sGBTsSPk69dV9hLRs2CwpC1VIumN1B6XvOD0wWnd5REvwq+xLIa +SJATIAiRyN0v43H2L4gnpulrBoV8x3E8vmSYVFeEqAB53tCVu1kCEeP7Eq/T/jrM5Uw3AFs51g04 hMCL9xcw==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.94.2 #2 (Red Hat Linux)) id 1nQ9l4-00FEIm-Sp; Fri, 04 Mar 2022 15:22:19 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id 819D530041D; Fri, 4 Mar 2022 16:22:17 +0100 (CET) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 0) id 6B7102012A030; Fri, 4 Mar 2022 16:22:17 +0100 (CET) Message-ID: <20220304152135.914397165@infradead.org> User-Agent: quilt/0.66 Date: Fri, 04 Mar 2022 16:19:54 +0100 From: Peter Zijlstra To: x86@kernel.org, mathias.nyman@linux.intel.com, gregkh@linuxfoundation.org Cc: linux-kernel@vger.kernel.org, peterz@infradead.org, rdunlap@infradead.org, linux-usb@vger.kernel.org Subject: [PATCH 1/3] x86/tsc: Be consistent about use_tsc_delay() References: <20220304151953.830111479@infradead.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org Currently loops_per_jiffy is set in tsc_early_init(), but then don't switch to delay_tsc, with the result that delay_loop is used with loops_per_jiffy set for delay_tsc. Then in (late) tsc_init() lpj_fine is set (which is mostly unused) and after which use_tsc_delay() is finally called. Move both loops_per_jiffy and use_tsc_delay() into tsc_enable_sched_clock() which is called the moment tsc_khz is determined, be it early or late. Keeping the lot consistent. Signed-off-by: Peter Zijlstra (Intel) --- arch/x86/kernel/tsc.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) --- a/arch/x86/kernel/tsc.c +++ b/arch/x86/kernel/tsc.c @@ -1487,6 +1487,9 @@ static unsigned long __init get_loops_pe static void __init tsc_enable_sched_clock(void) { + loops_per_jiffy = get_loops_per_jiffy(); + use_tsc_delay(); + /* Sanitize TSC ADJUST before cyc2ns gets initialized */ tsc_store_and_check_tsc_adjust(true); cyc2ns_init_boot_cpu(); @@ -1502,8 +1505,6 @@ void __init tsc_early_init(void) return; if (!determine_cpu_tsc_frequencies(true)) return; - loops_per_jiffy = get_loops_per_jiffy(); - tsc_enable_sched_clock(); } @@ -1537,7 +1538,6 @@ void __init tsc_init(void) enable_sched_clock_irqtime(); lpj_fine = get_loops_per_jiffy(); - use_tsc_delay(); check_system_tsc_reliable();