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 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id DC838FA3740 for ; Thu, 27 Oct 2022 17:26:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=DSMlzLDOU+p/D2URrXbBNuk5Wi3IYzmlVEYh+fbYCNU=; b=bQ+vs1gT3gvtBh 0mn4eVxHU1YF6ggLZSKxTG8+eapPHeoU33DQ69pNGy+JHeOUprAMwLQFkD5R++VXu/rAUMDlitX3u wvCk7bnQyB1XIftAEr/wxOc4nRRfVbtbwzyTCDfGY2hLw/x0r8jrROEEe7EKIWZRbW9P4JjJfcFNt moE5CZx5yMEoLXYJMWYPISFujnf72LgKsMWjzelnZ2sW4Y38t8UPRlvb1k72w0wXB3txyCVl5jbCj MIRLSbdJLd/DaXg0e5JSAWJhArPKQrrcp+0l5oDM1OXWJ9RdSbHL52ST4eVEl1WqHcdqanoYqWdus m4b3efBIxN8PHaKtwBwA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1oo6cv-00EM1L-Cd; Thu, 27 Oct 2022 17:25:09 +0000 Received: from casper.infradead.org ([2001:8b0:10b:1236::1]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1oo6cs-00ELzt-VS for linux-arm-kernel@bombadil.infradead.org; Thu, 27 Oct 2022 17:25:07 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.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; bh=xudGXE+bH5g0uONSt7W7O2capWykcQVvMeLlbM88H0c=; b=onax5cj46BBmSaer2uSKXZEkQs oA+FAjxCJOlLeWflBb9VqaU0mPXUetzMX4sRSEFNdQQV7deJs5IEMxW8YqxOBdy5KM7CPRm6W3YNz A6Z1jGTb7uG/eyXfAViZ+nOUoUlMFwXff8YQJfFBFd2ELbYvZiAwBcLw4wFcAjSnVw7R2+29163hL /FauygackP6NDvE/INb7d/CHDJFSwzXwwPVlQFCWKisG9DeGZEVl897BuI5KRjO4grAWxfOryKkIP tvzjtjebSFEj0PCd1NgIbaBQJmarf6VQ8QkfAVHviEhArYSEUlB8taSbVrKBoZ3q8omk9+/qZnSA8 kRRZSr8A==; Received: from j130084.upc-j.chello.nl ([24.132.130.84] helo=noisy.programming.kicks-ass.net) by casper.infradead.org with esmtpsa (Exim 4.94.2 #2 (Red Hat Linux)) id 1oo6cw-000RdB-7A; Thu, 27 Oct 2022 17:25:10 +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 (4096 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id 2174D30029C; Thu, 27 Oct 2022 19:25:05 +0200 (CEST) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 0DC6B2C450539; Thu, 27 Oct 2022 19:25:05 +0200 (CEST) Date: Thu, 27 Oct 2022 19:25:04 +0200 From: Peter Zijlstra To: James Clark Cc: linux-perf-users@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, broonie@kernel.org, acme@kernel.org, Andrew Kilroy , Vince Weaver , Mark Rutland , Ingo Molnar , Alexander Shishkin , Jiri Olsa , Namhyung Kim , Will Deacon , Catalin Marinas , kristina.martsenko@arm.com Subject: Re: [PATCH v2 1/1] perf arm64: Send pointer auth masks to ring buffer Message-ID: References: <20221020101921.1219533-1-james.clark@arm.com> <20221020101921.1219533-2-james.clark@arm.com> <4e50b890-0588-1551-fb7c-6cd8191d1054@arm.com> <8eb174c0-c785-c092-96f5-3a4fa3441287@arm.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <8eb174c0-c785-c092-96f5-3a4fa3441287@arm.com> X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Thu, Oct 27, 2022 at 03:11:47PM +0100, James Clark wrote: > Sorry for flip flopping, but I've read those threads that I linked and > spoke with Kristina and we would like to stick with the per sample > implementation after all. > > The reason is that in the future there may also be a prctrl for 48/52 > bit userspace addressing which would change the mask dynamically in the > same way as the enabled keys. Although this isn't possible now it makes > sense to do it this way in case of that, and also for consistency with > the ptrace feature. > > I also think that repeating the mask in this case has a very low impact > because if you are doing dwarf unwinding, then the whole stack is saved > anyway, so a few extra u64s wouldn't be noticeable. > > Are you ok with that and for me to resubmit with the expanded commit > message? But you can send a side-band thing around if/when it changes. Same as all the other stuff. We don't include MMAP data with each event either. Yes, the DWARF thing is slow as anything. but imagine needing this for something else as well, and then you're stuck with it. _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel