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=-5.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=no 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 1FE9EC49EA2 for ; Thu, 17 Jun 2021 10:23:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 099B561057 for ; Thu, 17 Jun 2021 10:23:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232203AbhFQKZu (ORCPT ); Thu, 17 Jun 2021 06:25:50 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37170 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232089AbhFQKZi (ORCPT ); Thu, 17 Jun 2021 06:25:38 -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 CCB9AC061280 for ; Thu, 17 Jun 2021 03:23:20 -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=sm7PZgjQz5zYbS6T2zkMlFmy5MlgXNyPsFshR7FkJog=; b=h6Qot+wKmU6avy4U655Lgf11Nt t7zMgpixnX1ZJy/BN59+D8giSYrvhJONKgJTMEzdiPFEkSAx1wbunr1xR6Z1+8X06BqR8+wCal6VJ j0kdWiLv6K4fN8cPbcfDBhtgcAz0CeeUnPBQzqOAaoNQy0b9V5lXqNLSn+qpRBVJkodHpz2GKB02v hHAAh2pyZfmj0OrMhI9L2cUIsYMwrNAO+W+3PAXXeFptxosgsqKd2JNF3jzjeK2rS+JobEOcwwals r5gCFjt9b8ud3xaAtemcbqm1UKwW69jYOXO3MUZEY9L4TlAKylAxy710mY5TEJxvwEOFS6wtKg4AV 4kADCdyQ==; 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 1ltpAt-008bTD-5c; Thu, 17 Jun 2021 10:23:10 +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 (2048 bits) server-digest SHA256) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id DC4A93001DB; Thu, 17 Jun 2021 12:23:06 +0200 (CEST) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id B0C3E2CC18C69; Thu, 17 Jun 2021 12:23:06 +0200 (CEST) Date: Thu, 17 Jun 2021 12:23:06 +0200 From: Peter Zijlstra To: kan.liang@linux.intel.com Cc: mingo@redhat.com, linux-kernel@vger.kernel.org, acme@kernel.org, mark.rutland@arm.com, ak@linux.intel.com, alexander.shishkin@linux.intel.com, namhyung@kernel.org, jolsa@redhat.com Subject: Re: [PATCH 0/4] perf: Fix the ctx->pmu for a hybrid system Message-ID: References: <1623869734-133974-1-git-send-email-kan.liang@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1623869734-133974-1-git-send-email-kan.liang@linux.intel.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jun 16, 2021 at 11:55:30AM -0700, kan.liang@linux.intel.com wrote: > To fix the issue, the generic perf codes have to understand the > supported CPU mask of a specific hybrid PMU. So it can update the > ctx->pmu accordingly, when a task is scheduled on a CPU which has > a different type of PMU from the previous CPU. The supported_cpus > has to be moved to the struct pmu. Urghh.. I so hate this :-/ I *did* point you to: https://lore.kernel.org/lkml/20181010104559.GO5728@hirez.programming.kicks-ass.net/ when you started this whole hybrid crud, and I think that's still the correct thing to do. Still, let me consider if there's a workable short-term cludge I hate less.