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 5E3DCC433F5 for ; Wed, 20 Apr 2022 18:44:49 +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-Type: Content-Transfer-Encoding:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:From:References:Cc:To:Subject: MIME-Version:Date:Message-ID:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=XUlwwttos/uq1aTEAaHmpkl1mdqWT2mJBzThBd3pij4=; b=nDwYiBDdBckxdF fn2Z1bPflk87FJBoFxhGNR02mhBqcU/65jai0naMiksjHNfrp7zw/BcVb4LoEVB8jo+idKN8o7/0n X1DckmLzQccAOOxgknxA21eyU4sxwp8u47B76nzW5Guk7lm/rtem0/ciLW/ADsM3xUrlxnyAmys53 IQU2aIs7oANXvVs8059Si+AQ2t/f3Rop+m4On3gINVcdEgbkFroSkzz0Zv+sO1+plAyYVYQVfrA63 2+M6GqWyDFQ0YCLh6V1v+hewQlKAkn6AmGALLx/WFVuJ+waFgPMbLpfIt6YD9ykeRukPsds9tzj2p lemYos1jpLXzqXCQWxNg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1nhFIl-00A5Ky-De; Wed, 20 Apr 2022 18:43:43 +0000 Received: from mga03.intel.com ([134.134.136.65]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1nhFIh-00A5Ig-Kx for linux-arm-kernel@lists.infradead.org; Wed, 20 Apr 2022 18:43:41 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1650480219; x=1682016219; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=JVLsyYBZq1esqPxRCB4pCE4fLG7rN1RBuCQlNd7wmv0=; b=LxowGVslhUWiG7H7iVC4eb74kflXIUjyHfLs06PBT5XHdfW7Y+xf6w/s bzcWsJ8zOHIhrnOD8By/b6K8/OoJHjRvyLdAoQNNPUM64lQh8yap4grYN wBDkWrbYYIGxEHnQ32A3jwimrrJUpQSNNkUjmPgclb3VK2dwSHkZ8UTKp T0HO4zOJ7OTlC4AR4H8deoVV+3oOfky6Js0zs5jwcdKYjeWBYiz9+PlES PsS60Cvw3JM7/S59AaYUnI52SAJZV9iBw3FgoG+QOGlLt1RNGu+TgiEoc 1oEUi1fVABk8iUqEnTG/WKH89k22Lqw6IEDYjs9gMLJdp8ww/Kf4D4tkK A==; X-IronPort-AV: E=McAfee;i="6400,9594,10323"; a="263886756" X-IronPort-AV: E=Sophos;i="5.90,276,1643702400"; d="scan'208";a="263886756" Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by orsmga103.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 20 Apr 2022 11:43:32 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.90,276,1643702400"; d="scan'208";a="647785859" Received: from linux.intel.com ([10.54.29.200]) by FMSMGA003.fm.intel.com with ESMTP; 20 Apr 2022 11:43:31 -0700 Received: from [10.209.97.182] (kliang2-MOBL.ccr.corp.intel.com [10.209.97.182]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by linux.intel.com (Postfix) with ESMTPS id D8F01580AE2; Wed, 20 Apr 2022 11:43:29 -0700 (PDT) Message-ID: Date: Wed, 20 Apr 2022 14:43:28 -0400 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.8.0 Subject: Re: [PATCH v5 2/5] perf: Add SNOOP_PEER flag to perf mem data struct Content-Language: en-US To: Ali Saidi , linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, linux-arm-kernel@lists.infradead.org, german.gomez@arm.com, leo.yan@linaro.org, acme@kernel.org Cc: benh@kernel.crashing.org, Nick.Forrington@arm.com, alexander.shishkin@linux.intel.com, andrew.kilroy@arm.com, james.clark@arm.com, john.garry@huawei.com, jolsa@kernel.org, kjain@linux.ibm.com, lihuafei1@huawei.com, mark.rutland@arm.com, mathieu.poirier@linaro.org, mingo@redhat.com, namhyung@kernel.org, peterz@infradead.org, will@kernel.org References: <20220408195344.32764-1-alisaidi@amazon.com> <20220408195344.32764-3-alisaidi@amazon.com> From: "Liang, Kan" In-Reply-To: <20220408195344.32764-3-alisaidi@amazon.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220420_114339_817674_0FA9F41A X-CRM114-Status: GOOD ( 20.75 ) 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-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 4/8/2022 3:53 PM, Ali Saidi wrote: > Add a flag to the perf mem data struct to signal that a request caused a > cache-to-cache transfer of a line from a peer of the requestor and > wasn't sourced from a lower cache level. It sounds similar to the Forward state. Why can't the PERF_MEM_SNOOPX_FWD be reused? Thanks, Kan > The line being moved from one > peer cache to another has latency and performance implications. On Arm64 > Neoverse systems the data source can indicate a cache-to-cache transfer > but not if the line is dirty or clean, so instead of overloading HITM > define a new flag that indicates this type of transfer. > > Signed-off-by: Ali Saidi > --- > include/uapi/linux/perf_event.h | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/include/uapi/linux/perf_event.h b/include/uapi/linux/perf_event.h > index 82858b697c05..c9e58c79f3e5 100644 > --- a/include/uapi/linux/perf_event.h > +++ b/include/uapi/linux/perf_event.h > @@ -1308,7 +1308,7 @@ union perf_mem_data_src { > #define PERF_MEM_SNOOP_SHIFT 19 > > #define PERF_MEM_SNOOPX_FWD 0x01 /* forward */ > -/* 1 free */ > +#define PERF_MEM_SNOOPX_PEER 0x02 /* xfer from peer */ > #define PERF_MEM_SNOOPX_SHIFT 38 > > /* locked instruction */ _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel