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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 60B9AC433EF for ; Wed, 16 Mar 2022 17:26:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1357523AbiCPR11 (ORCPT ); Wed, 16 Mar 2022 13:27:27 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49236 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232691AbiCPR1Z (ORCPT ); Wed, 16 Mar 2022 13:27:25 -0400 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 11010AE66; Wed, 16 Mar 2022 10:26:11 -0700 (PDT) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id CA3B31476; Wed, 16 Mar 2022 10:26:10 -0700 (PDT) Received: from [10.57.44.7] (unknown [10.57.44.7]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id C82FB3F7D7; Wed, 16 Mar 2022 10:26:08 -0700 (PDT) Message-ID: <73353bec-6949-dd0b-ff1c-a8143e169602@arm.com> Date: Wed, 16 Mar 2022 17:26:07 +0000 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.5.0 Subject: Re: [PATCH V4 04/10] perf: Capture branch privilege information Content-Language: en-US To: Anshuman Khandual , linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, peterz@infradead.org, acme@kernel.org Cc: Robin Murphy , Suzuki Poulose , Ingo Molnar , Mark Rutland , Alexander Shishkin , Jiri Olsa , Namhyung Kim , Thomas Gleixner , Will Deacon , linux-arm-kernel@lists.infradead.org References: <20220315053516.431515-1-anshuman.khandual@arm.com> <20220315053516.431515-5-anshuman.khandual@arm.com> From: James Clark In-Reply-To: <20220315053516.431515-5-anshuman.khandual@arm.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 15/03/2022 05:35, Anshuman Khandual wrote: > Platforms like arm64 could capture privilege level information for all the > branch records. Hence this adds a new element in the struct branch_entry to > record the privilege level information, which could be requested through a > new event.attr.branch_sample_type based flag PERF_SAMPLE_BRANCH_PRIV_SAVE. > This flag helps user choose whether privilege information is captured. > Reviewed-by: James Clark > Cc: Peter Zijlstra > Cc: Ingo Molnar > Cc: Arnaldo Carvalho de Melo > Cc: Mark Rutland > Cc: Alexander Shishkin > Cc: Jiri Olsa > Cc: Namhyung Kim > Cc: Thomas Gleixner > Cc: Will Deacon > Cc: linux-arm-kernel@lists.infradead.org > Cc: linux-perf-users@vger.kernel.org > Cc: linux-kernel@vger.kernel.org > Signed-off-by: Anshuman Khandual > --- > include/uapi/linux/perf_event.h | 14 +++++++++++++- > 1 file changed, 13 insertions(+), 1 deletion(-) > > diff --git a/include/uapi/linux/perf_event.h b/include/uapi/linux/perf_event.h > index d29280adc3c4..193dba2ecdc1 100644 > --- a/include/uapi/linux/perf_event.h > +++ b/include/uapi/linux/perf_event.h > @@ -204,6 +204,8 @@ enum perf_branch_sample_type_shift { > > PERF_SAMPLE_BRANCH_HW_INDEX_SHIFT = 17, /* save low level index of raw branch records */ > > + PERF_SAMPLE_BRANCH_PRIV_SAVE_SHIFT = 18, /* save privilege mode */ > + > PERF_SAMPLE_BRANCH_MAX_SHIFT /* non-ABI */ > }; > > @@ -233,6 +235,8 @@ enum perf_branch_sample_type { > > PERF_SAMPLE_BRANCH_HW_INDEX = 1U << PERF_SAMPLE_BRANCH_HW_INDEX_SHIFT, > > + PERF_SAMPLE_BRANCH_PRIV_SAVE = 1U << PERF_SAMPLE_BRANCH_PRIV_SAVE_SHIFT, > + > PERF_SAMPLE_BRANCH_MAX = 1U << PERF_SAMPLE_BRANCH_MAX_SHIFT, > }; > > @@ -271,6 +275,13 @@ enum { > PERF_BR_NEW_MAX, > }; > > +enum { > + PERF_BR_PRIV_UNKNOWN = 0, > + PERF_BR_PRIV_USER = 1, > + PERF_BR_PRIV_KERNEL = 2, > + PERF_BR_PRIV_HV = 3, > +}; > + > #define PERF_SAMPLE_BRANCH_PLM_ALL \ > (PERF_SAMPLE_BRANCH_USER|\ > PERF_SAMPLE_BRANCH_KERNEL|\ > @@ -1386,7 +1397,8 @@ struct perf_branch_entry { > cycles:16, /* cycle count to last branch */ > type:4, /* branch type */ > new_type:4, /* additional branch type */ > - reserved:36; > + priv:3, /* privilege level */ > + reserved:33; > }; > > union perf_sample_weight {