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=-8.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SPF_HELO_NONE,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 D0D63C433C1 for ; Tue, 23 Mar 2021 21:43:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9D88A619CC for ; Tue, 23 Mar 2021 21:43:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233652AbhCWVm6 (ORCPT ); Tue, 23 Mar 2021 17:42:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58434 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233856AbhCWVmP (ORCPT ); Tue, 23 Mar 2021 17:42:15 -0400 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 B1565C061764 for ; Tue, 23 Mar 2021 14:42:11 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=8rNFDdFuXcvKEbcGYkkCSUHerc7FqNZ2rVvQuj4NgXc=; b=fyzmbsSXFIEU7Oku2tQlk8WIt8 zPMmJHqW/d84PSQVOl8tlhtWGFuiK6gPKxnRK0YbVELnP81Hytm9o1jo8nhbRwxMzEW4iyUBkdny9 iEcTMjOjmYKJ85Toc0VHX1FfaJNlCM3ScKqSLzRfJh2wxbD+/v5kK54dGhPiPEYMsCAfeQKforELP VZGdDitOT+1TZRRCYZtWxHggAnFYWUrDocmG8sIr/mqnPxI63ouCOdOQZEXwQxN4PDkP50qpIlZIb AxK+Tl/olEV8BrIw/vpVdoQXlNSv6b7WwKcbGC7z27FD1A7Q1aV1tcxgM6VkOiQvoeLEBxDz2OyPw 9aKCwKHw==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=worktop.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.94 #2 (Red Hat Linux)) id 1lOomT-00FnlG-07; Tue, 23 Mar 2021 21:41:46 +0000 Received: by worktop.programming.kicks-ass.net (Postfix, from userid 1000) id 9AF0B9864F6; Tue, 23 Mar 2021 22:41:40 +0100 (CET) Date: Tue, 23 Mar 2021 22:41:40 +0100 From: Peter Zijlstra To: Like Xu Cc: Ingo Molnar , Arnaldo Carvalho de Melo , Mark Rutland , Alexander Shishkin , Jiri Olsa , Namhyung Kim , Thomas Gleixner , Borislav Petkov , Kan Liang , x86@kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v4 RESEND 3/5] perf/x86/lbr: Move cpuc->lbr_xsave allocation out of sleeping region Message-ID: <20210323214140.GE4746@worktop.programming.kicks-ass.net> References: <20210322060635.821531-1-like.xu@linux.intel.com> <20210322060635.821531-4-like.xu@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210322060635.821531-4-like.xu@linux.intel.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Mar 22, 2021 at 02:06:33PM +0800, Like Xu wrote: > diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c > index 18df17129695..a4ce669cc78d 100644 > --- a/arch/x86/events/core.c > +++ b/arch/x86/events/core.c > @@ -373,7 +373,7 @@ set_ext_hw_attr(struct hw_perf_event *hwc, struct perf_event *event) > return x86_pmu_extra_regs(val, event); > } > > -int x86_reserve_hardware(void) > +int x86_reserve_hardware(struct perf_event *event) > { > int err = 0; > > @@ -382,8 +382,10 @@ int x86_reserve_hardware(void) > if (atomic_read(&pmc_refcount) == 0) { > if (!reserve_pmc_hardware()) > err = -EBUSY; > - else > + else { > reserve_ds_buffers(); > + reserve_lbr_buffers(event); > + } > } > if (!err) > atomic_inc(&pmc_refcount); This makes absolutely no sense what so ever. This is only executed for the first event that gets here.