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=-2.0 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 D4E97C43603 for ; Wed, 4 Dec 2019 12:37:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 92AF02077B for ; Wed, 4 Dec 2019 12:37:11 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="VSpWWV6N" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727682AbfLDMhK (ORCPT ); Wed, 4 Dec 2019 07:37:10 -0500 Received: from bombadil.infradead.org ([198.137.202.133]:53138 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726586AbfLDMhK (ORCPT ); Wed, 4 Dec 2019 07:37:10 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; 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:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=ZzCSk1fVGYsKa4mpW0zBDhBYag2lMaeRmgfUQsjzofc=; b=VSpWWV6N9rXAO9kLKhiJRE3F5 iNh1HYE80pUy8AL8f7MyKpGWxahVW3jZovgSnjqrsDu5CTJvnzkfTUzcapUndYxtdLHqHL0pektto Hg71pS/EaXlZnEXOoTPG/FJkGiEkp8o+wHDAMoHzPIz/avdrp/kqEbAyWcBLB3gNZiR0K/hF7g1JW EqbSuLG4eKQwqvd9dUsk8QdoWfZKtIKyGYr1lIrbaHalcQPHyezC7jqTN0zY/AFXKjIuF714XZVr6 +0Bopg2tiJnCr7YGp9F9OWXAu85mTPRcNXdxGU4zqBzWcwZBKANgXPsV8HYL9AnYv1diEDW+MrEAE KmiZ4bCAg==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by bombadil.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1icTtr-00087U-6I; Wed, 04 Dec 2019 12:36:59 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id 3961D3011E0; Wed, 4 Dec 2019 13:35:40 +0100 (CET) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id D4BC82024721C; Wed, 4 Dec 2019 13:36:56 +0100 (CET) Date: Wed, 4 Dec 2019 13:36:56 +0100 From: Peter Zijlstra To: "Liang, Kan" Cc: mingo@redhat.com, acme@kernel.org, tglx@linutronix.de, bp@alien8.de, linux-kernel@vger.kernel.org, eranian@google.com, alexey.budankov@linux.intel.com, vitaly.slobodskoy@intel.com, ak@linux.intel.com Subject: Re: [RFC PATCH 2/8] perf: Helpers for alloc/init/fini PMU specific data Message-ID: <20191204123656.GU2844@hirez.programming.kicks-ass.net> References: <1574954071-6321-1-git-send-email-kan.liang@linux.intel.com> <1574954071-6321-2-git-send-email-kan.liang@linux.intel.com> <20191202131646.GD2827@hirez.programming.kicks-ass.net> <2d036aa5-542a-8c01-762c-3b68136887f5@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <2d036aa5-542a-8c01-762c-3b68136887f5@linux.intel.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Dec 02, 2019 at 03:35:00PM -0500, Liang, Kan wrote: > Could you please give me an example? There's a ton of refcounting in perf, none of it follows this pattern. > I think we do need something to protect the refcount. Are you suggesting > atomic_*? refcount_t comes to mind.