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 5B733C433EF for ; Tue, 19 Apr 2022 14:55:06 +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: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=QDLw2Uff4gP7SKjI+bmuLm/9PU3ih8p53yoJqiuwECI=; b=TMMnvz/oIfdBN8 snTTQp/x2NdqryxVAR5Hi9tiL0lg68qkTNLdiY3FbryrdkcXdFDLQrEOFrY3q6lhCCuqexW1NL5L8 awrHOe5Cip0/oYgV3hxF6cVou2Jb2n3ZQX9Rg3eTW/VngMeh1qKDRdIF8iwLCUzTCRHtbJR9CNk/e 8f+mn1iTx7oTrkiCCoy/TLchdEMaDxJTXpcFL4OCJMB+bThJKBVYGl+TaYZSw6YytHd+wWMCEWnoh ZI1xuO3Cdd7EUeJ775jsU4m95nCqfTszyq/0jTEKMLbL7MSCeMOxg2TXacy8m9hAME4upGx/5M/mb eJTWRimKKYdpygohI5jQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1ngpEh-004QcT-KE; Tue, 19 Apr 2022 14:53:47 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1ngoLH-0043Lj-Bz for linux-arm-kernel@lists.infradead.org; Tue, 19 Apr 2022 13:56:34 +0000 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 047E31063; Tue, 19 Apr 2022 06:56:30 -0700 (PDT) Received: from [10.32.36.25] (e121896.Emea.Arm.com [10.32.36.25]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id EC7023F766; Tue, 19 Apr 2022 06:56:26 -0700 (PDT) Message-ID: Date: Tue, 19 Apr 2022 14:56:25 +0100 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.7.0 Subject: Re: [PATCH V5 2/8] perf: Extend branch type classification 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: <20220404045046.634522-1-anshuman.khandual@arm.com> <20220404045046.634522-3-anshuman.khandual@arm.com> From: James Clark In-Reply-To: <20220404045046.634522-3-anshuman.khandual@arm.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220419_065631_730048_C33838C0 X-CRM114-Status: GOOD ( 24.77 ) 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 04/04/2022 05:50, Anshuman Khandual wrote: > branch_entry.type now has ran out of space to accommodate more branch types > classification. This will prevent perf branch stack implementation on arm64 > (via BRBE) to capture all available branch types. Extending this bit field > i.e branch_entry.type [4 bits] is not an option as it will break user space > ABI both for little and big endian perf tools. > > Extend branch classification with a new field branch_entry.new_type via a > new branch type PERF_BR_EXTEND_ABI in branch_entry.type. Perf tools which > could decode PERF_BR_EXTEND_ABI, will then parse branch_entry.new_type as > well. > > branch_entry.new_type is a 4 bit field which can hold upto 16 branch types. > The first three branch types will hold various generic page faults followed > by five architecture specific branch types, which can be overridden by the > platform for specific use cases. These architecture specific branch types > gets overridden on arm64 platform for BRBE implementation. > > New generic branch types > > - PERF_BR_NEW_FAULT_ALGN > - PERF_BR_NEW_FAULT_DATA > - PERF_BR_NEW_FAULT_INST > > New arch specific branch types > > - PERF_BR_NEW_ARCH_1 > - PERF_BR_NEW_ARCH_2 > - PERF_BR_NEW_ARCH_3 > - PERF_BR_NEW_ARCH_4 > - PERF_BR_NEW_ARCH_5 > > 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 Reviewed-by: James Clark > --- > include/uapi/linux/perf_event.h | 16 +++++++++++++++- > 1 file changed, 15 insertions(+), 1 deletion(-) > > diff --git a/include/uapi/linux/perf_event.h b/include/uapi/linux/perf_event.h > index 26d8f0b5ac0d..d29280adc3c4 100644 > --- a/include/uapi/linux/perf_event.h > +++ b/include/uapi/linux/perf_event.h > @@ -255,9 +255,22 @@ enum { > PERF_BR_IRQ = 12, /* irq */ > PERF_BR_SERROR = 13, /* system error */ > PERF_BR_NO_TX = 14, /* not in transaction */ > + PERF_BR_EXTEND_ABI = 15, /* extend ABI */ > PERF_BR_MAX, > }; > > +enum { > + PERF_BR_NEW_FAULT_ALGN = 0, /* Alignment fault */ > + PERF_BR_NEW_FAULT_DATA = 1, /* Data fault */ > + PERF_BR_NEW_FAULT_INST = 2, /* Inst fault */ > + PERF_BR_NEW_ARCH_1 = 3, /* Architecture specific */ > + PERF_BR_NEW_ARCH_2 = 4, /* Architecture specific */ > + PERF_BR_NEW_ARCH_3 = 5, /* Architecture specific */ > + PERF_BR_NEW_ARCH_4 = 6, /* Architecture specific */ > + PERF_BR_NEW_ARCH_5 = 7, /* Architecture specific */ > + PERF_BR_NEW_MAX, > +}; > + > #define PERF_SAMPLE_BRANCH_PLM_ALL \ > (PERF_SAMPLE_BRANCH_USER|\ > PERF_SAMPLE_BRANCH_KERNEL|\ > @@ -1372,7 +1385,8 @@ struct perf_branch_entry { > abort:1, /* transaction abort */ > cycles:16, /* cycle count to last branch */ > type:4, /* branch type */ > - reserved:40; > + new_type:4, /* additional branch type */ > + reserved:36; > }; > > union perf_sample_weight { _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel