From patchwork Thu Sep 1 13:26:56 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: James Clark X-Patchwork-Id: 12962647 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 CA160ECAAD1 for ; Thu, 1 Sep 2022 13:35:08 +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:MIME-Version:Message-Id:Date:Subject:Cc :To:From:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References: List-Owner; bh=zHHBg1QYLS6AK1z90ZBKCxp5e9iKvBdocZxBZCz4OxM=; b=C2IpP9qmJXswcj pOlcrk/3UTrKKPe6YJi82KwcErMfxZFTTab9wzdkXhmSSf7ds5UOf4ZbT14131NOZWe+pPPTLseZl OWy3QVK8zUD6ORkq/zIHwxv0PmrU7VAKrLwpGQ4UZayU+f8UXjb06p2Q2wpTRPCJXvG2Gzm60920D OefSeFxWB4laovxj3mnAROQIzdfvjzsRchmbiEZ4+R+TyA+XL3xI5i/VQzR6KRQubIK+9IhGU0Mim tE0Z4HQLL8a+xAg0vU/76p1T2jJ4Odrpi7lOjvbFE17oIno3iirmf8rtxEtJTzb3vUayQmtWZL0Cj cxm5MLA24FWSwCAUwVAg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1oTkKU-00C5Qd-Lo; Thu, 01 Sep 2022 13:33:59 +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 1oTkEG-00C24u-Vs for linux-arm-kernel@lists.infradead.org; Thu, 01 Sep 2022 13:27:35 +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 DBAE7D6E; Thu, 1 Sep 2022 06:27:32 -0700 (PDT) Received: from e121896.arm.com (unknown [10.57.16.42]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 11CB83F7B4; Thu, 1 Sep 2022 06:27:52 -0700 (PDT) From: James Clark To: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, broonie@kernel.org, acme@kernel.org, leo.yan@linaro.org, john.garry@huawei.com, catalin.marinas@arm.com, will@kernel.org, James Clark , Jonathan Corbet , Mark Rutland , linux-doc@vger.kernel.org Subject: [PATCH v3 0/2] perf: arm64: Kernel support for Dwarf unwinding through SVE functions Date: Thu, 1 Sep 2022 14:26:56 +0100 Message-Id: <20220901132658.1024635-1-james.clark@arm.com> X-Mailer: git-send-email 2.28.0 MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220901_062733_134134_BA7BEB70 X-CRM114-Status: GOOD ( 14.08 ) 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 Hi, I'm resubmitting this with a few of the changes suggested by Will on V2. I haven't made any changes regarding the open questions about the discoverability or saving the new reg and passing to output_sample() because I think it's best to be consistent with the implementations on other platforms first. I have explained in more detail on v2 [1]. [1]: https://lore.kernel.org/lkml/5fcf1a6f-c8fb-c296-992e-18aae8874095@arm.com/ ======= Changes since v2: * Add definition for PERF_REG_EXTENDED_MASK which is needed for PERF_PMU_CAP_EXTENDED_REGS to work properly * Simplify changes to enum perf_event_arm_regs Changes since v1: * Add Mark's review tag * Clarify in docs that it's the SVE register length * Split patchset into kernel side and Perf tool changes ======= When SVE registers are pushed onto the stack the VG register is required to unwind because the stack offsets would vary by the SVE register width at the time when the sample was taken. These first two patches add support for sampling the VG register to the kernel and the docs. There is another patchset to add support to userspace perf. A small change is also required to libunwind or libdw depending on which unwinder is used, and these will be published later. Without these changes Perf continues to work with both libraries, although the VG register is still not used for unwinding. Thanks James James Clark (2): perf: arm64: Add SVE vector granule register to user regs arm64/sve: Add Perf extensions documentation Documentation/arm64/sve.rst | 20 +++++++++++++++++ arch/arm64/include/uapi/asm/perf_regs.h | 7 ++++++ arch/arm64/kernel/perf_regs.c | 30 +++++++++++++++++++++++-- drivers/perf/arm_pmu.c | 2 +- 4 files changed, 56 insertions(+), 3 deletions(-)