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 861C6C3271F for ; Fri, 5 Jul 2024 10:34:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=YV31UWEg8nqTKxNGTfd8XnNg5IvRR8O6w9IVeB6fHxc=; b=SLgn2yxa/wakPQSkeAPHANmKso 21Z5/Y+sY/zgLrr/9ePtPdMD5nZeMAFkDdrtcNHigU1vAmmCtg2kQUyOjVGBAoI51unXwnuEodFfg bA3qMkMfMfZcMdiTwqFdtoF67NaaznF9VGqDpPw4Fmd2WrY4M0cxvuQIlgWO94PeZaTcPec1hTny4 aFNOzwm3RoIQ2k5BP8CSihOd9EmfFQoiTNhpLfilm31uwLUu7Pd6ipDoSAnxIvERc9kMjAeGZAPJj ZphnwkbDS0SpcTcrzCmywv9K6W4bkxBHItmKG6E4U1DDVNbyYVYGEyrw+7VxFnyyQbHYhiNhB9vn+ LkHzQtJw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1sPgGw-0000000Fepx-2Lxz; Fri, 05 Jul 2024 10:34:34 +0000 Received: from dfw.source.kernel.org ([139.178.84.217]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1sPgGi-0000000FenL-36Hd for linux-arm-kernel@lists.infradead.org; Fri, 05 Jul 2024 10:34:22 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id C182E62B9C; Fri, 5 Jul 2024 10:34:19 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4B308C116B1; Fri, 5 Jul 2024 10:34:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1720175659; bh=OHwCYZYWuxr2zibh0sQUzfqPPVvOiWBqC8XZucSKSvk=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=d3safjMw/dDD3rJLDXb4XhWm2WKeYsnc1ctTMrqVkE8pKfVodLxHeKO3Dl7M2tmaG RLlM8EsRhZyAJSjcexvOmNNb86bntNpEQCEEn8cchKb2M6GlG7aG1aayYkk6egYUJp hXFXJRYYOdslWYc14Ow/awXNWVHHzRpqVWCLvR8Rdzy4Ed4gvCkZgnQ72AuxtquCUr 7z5fYzuUPLqqEYIDAMkZEiF1vIWdWYR0TS5xEWYLH0aFmxWIbFw94ZAg7bVtYQy3U0 W5ROIRgRP6Hia3VBf/OkpHm/aUN1Tvxtlyrw+wKeh9mnKLMM9Nn3/DmRaaNVX2X0Kl MJSaSH4t6ouXQ== Date: Fri, 5 Jul 2024 11:34:13 +0100 From: Will Deacon To: Tiezhu Yang Cc: Mark Rutland , Russell King , Catalin Marinas , Oleg Nesterov , Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Namhyung Kim , linux-arm-kernel@lists.infradead.org, linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 1/3] perf: Add perf_event_attr::bp_priv Message-ID: <20240705103413.GA8971@willie-the-truck> References: <20240621073910.8465-1-yangtiezhu@loongson.cn> <20240621073910.8465-2-yangtiezhu@loongson.cn> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240621073910.8465-2-yangtiezhu@loongson.cn> User-Agent: Mutt/1.10.1 (2018-07-13) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240705_033420_866833_344C2786 X-CRM114-Status: GOOD ( 21.20 ) 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: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Fri, Jun 21, 2024 at 03:39:08PM +0800, Tiezhu Yang wrote: > Add a member "bp_priv" at the end of the uapi struct perf_event_attr > to make a bridge between ptrace and hardware breakpoint. > > This is preparation for later patch on some archs such as ARM, ARM64 > and LoongArch which have privilege level of breakpoint. > > Signed-off-by: Tiezhu Yang > --- > include/uapi/linux/perf_event.h | 3 +++ > kernel/events/hw_breakpoint.c | 1 + > 2 files changed, 4 insertions(+) > > diff --git a/include/uapi/linux/perf_event.h b/include/uapi/linux/perf_event.h > index 3a64499b0f5d..f9f917e854e6 100644 > --- a/include/uapi/linux/perf_event.h > +++ b/include/uapi/linux/perf_event.h > @@ -379,6 +379,7 @@ enum perf_event_read_format { > #define PERF_ATTR_SIZE_VER6 120 /* add: aux_sample_size */ > #define PERF_ATTR_SIZE_VER7 128 /* add: sig_data */ > #define PERF_ATTR_SIZE_VER8 136 /* add: config3 */ > +#define PERF_ATTR_SIZE_VER9 144 /* add: bp_priv */ > > /* > * Hardware event_id to monitor via a performance monitoring event: > @@ -522,6 +523,8 @@ struct perf_event_attr { > __u64 sig_data; > > __u64 config3; /* extension of config2 */ > + > + __u8 bp_priv; /* privilege level of breakpoint */ > }; Why are we extending the user ABI for this? Perf events already have the privilege encoded (indirectly) by the exclude_{user,kernel,hv} fields in 'struct perf_event_attr'. Will