From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 02FBE1FBEA5 for ; Tue, 3 Dec 2024 18:04:42 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1733249083; cv=none; b=qTG984NmPvjmKM5qYvml1/CYNneUBQmNkyxWaLLOZ25td5Lkdsy9p8c0Yjpt3f/AAMOO78gxNcPXufV334IYvRG3YU1XQMFRpPTW9k09T7vkHdC9coYC7cab6PFRpXrUXv7/n5xOd2p7PNXpH3ZT9sRgYnpEmQ+fIhqtln0PC3E= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1733249083; c=relaxed/simple; bh=m9oWvK5bOeQAAs9/R49XPd8h7UE2JPqfV743Ea8xDsM=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=YG5tQSRz4Uma+8EtnY+dNd0MTqygEwsART8v9/QqFFb6oJv3mBbSt9x7+sv/8QhvAlEc8w5BC2rOwp7t2psIe0c2KOtr4psD8scSTIhpjrntiO6Pb2H4SerGc2GnTwRJONZErv9kzTEYPH9XW3cgmajCJ6gkz4p0mnwCPkuT/Lk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=cEVFvJrW; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="cEVFvJrW" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 37E9FC4CECF; Tue, 3 Dec 2024 18:04:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1733249082; bh=m9oWvK5bOeQAAs9/R49XPd8h7UE2JPqfV743Ea8xDsM=; h=From:To:Cc:Subject:Date:From; b=cEVFvJrWzzKkKkBLcG6gMSM0H39ra/39SlyqANv/PS/k3oxOT7Fo3bRUMMBluAxfQ ygskOUfIhIaudeGXUEaboU/1Ac+66LKR3OqGNbf3juv6kWLdcgIh2l0hrOehpbLD5Y 1TMEP0K0zzqu1nYBBYjpRC7U87hUU7oQvImHM2zjuQmn/Mau83WHHDbu+Pwzp8yxk3 3C0u5YUDyq7G0U66FlaCPfneIKqBJaQ+rDxQEkGkumOQtSiSs3Fz1ItJc3Gi+5jWA/ n71pCDr3YXA+Q+D/gzkTZoga1srb1AQyIzkZ1Tzsw7wJkRqOK9Mq2H9IGKqqiNRPoG jHZqeIoCTd4qA== From: Namhyung Kim To: Peter Zijlstra , Ingo Molnar Cc: Kan Liang , Mark Rutland , Alexander Shishkin , Arnaldo Carvalho de Melo , LKML Subject: [PATCH v6 0/2] perf: Relex privilege restriction on AMD IBS Date: Tue, 3 Dec 2024 10:04:39 -0800 Message-ID: <20241203180441.1634709-1-namhyung@kernel.org> X-Mailer: git-send-email 2.47.0.338.g60cca15819-goog Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Hello, This is v6 to allow AMD IBS to regular users on the default settings where kernel-level profiling is disabled (perf_event_paranoid=2). Currently AMD IBS doesn't allow any kind of exclusion in the event attribute. But users needs to set attr.exclude_kernel to open an event on such an environment. v6 changes) * add Reviewed-and-tested-by from Ravi v5) https://lore.kernel.org/lkml/20241028200153.1466731-1-namhyung@kernel.org * drop PERF_FORMAT_DROPPED support for now * add Acked-by from Thomas for s390 v4) https://lore.kernel.org/lkml/20241023000928.957077-1-namhyung@kernel.org * remove RFC tag * fix sysfs attribute for ibs_fetch/format (Ravi) * handle exclude_hv as well, so ":u" modifier would work for IBS * add Acked and Reviewed-by from Kyle and Madhavan v3) https://lore.kernel.org/lkml/20240905031027.2567913-1-namhyung@kernel.org * fix build on s390 * add swfilt format for attr.config2 * count powerpc core-book3s dropped samples v2) https://lore.kernel.org/lkml/20240830232910.1839548-1-namhyung@kernel.org/ * add PERF_FORMAT_DROPPED * account dropped sw events and from BPF handler * use precise RIP from IBS record v1) https://lore.kernel.org/lkml/20240822230816.564262-1-namhyung@kernel.org/ While IBS doesn't support hardware level privilege filters, the kernel can allow the event and drop samples belongs to the kernel like in the software events. This is limited but it still contains precise samples which is important for various analysis like data type profiling. This version added format/swfilt file in sysfs to expose the software filtering by setting the attribute config2 value. I think it's easier to add a new config rather than adding a new PMU in order to handle event multiplexing across IBS PMU. Users can use the perf tool to enable this feature manually like below. Probably the perf tool can handle this automatically in the future. $ perf record -e ibs_op/swfilt=1/u $PROG Let me know what you think. Thanks, Namhyung Namhyung Kim (2): perf/core: Export perf_exclude_event() perf/x86: Relax privilege filter restriction on AMD IBS arch/s390/kernel/perf_cpum_sf.c | 6 ++-- arch/x86/events/amd/ibs.c | 59 +++++++++++++++++++++++---------- include/linux/perf_event.h | 6 ++++ kernel/events/core.c | 3 +- 4 files changed, 51 insertions(+), 23 deletions(-) -- 2.47.0.338.g60cca15819-goog