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 381E33A1DB for ; Mon, 28 Oct 2024 20:01:54 +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=1730145715; cv=none; b=XIIiKBcEmz06ASdwbfP40v0sUICOebzPOIYnIj7OeJ0d5KGR/vNdnfVE6ZHtYBvckprkul2I3Nt1Ae+2q92UNc9TXLd93z2Ltwy8GdIwh9HZVfEYv+fp+6Ay5+qimtJViiCbgTseqEcR8YVRyjp3uw7LfjOWQvafjpN5E18ELlc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730145715; c=relaxed/simple; bh=/D3Hbmc4k31cO962NwxHMcfECtTuA5a+tAZ1KwkPABA=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=iGGGY61x0eZO3Pvzpp1m5T4zhItmYGiXC/OrV4tswiS1eGH2+vCbmvyXSCc6DNXqWCUyTmTe9FRFiCB+h0g3T1sQA31PyUUGppKUsRvKwfnvBLZ/KnPvlQulp7ZPBzNkHQZ43SBohDhGbGpHLCKBMfZodsvNr/YedEBCtX85QXo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Lv3dmlR+; 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="Lv3dmlR+" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 74932C4CEC3; Mon, 28 Oct 2024 20:01:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1730145714; bh=/D3Hbmc4k31cO962NwxHMcfECtTuA5a+tAZ1KwkPABA=; h=From:To:Cc:Subject:Date:From; b=Lv3dmlR+7TnMQuuX0hq+UH5lEgPbQnPzaAFtJ1nFP+/cq6FSWAJn2o+Gz55+d37gt Cr/MvUgyTHtDB0S2vz0SDCTXryqBqKSQZ7ewuxiYK5wWa2OFFqomHrlNyoHdE2if8e 9DO4ZN0/k5r/NsZcm+mXZHfsGwGDrfeAdUz3ttktscw8Qth7GNVkQwZAAmeEWsbObh 6oHbhORDsKDt2F4uIAXpyXxBX9IE8uQl8SDeW7TaYFdEbL7tIa7dxhybcnsaYjnn9P FRjMDzRbrliyLZilFK39IkupRliR0h0D+27F5qiecwNU/yCvD61MOMHUImVtBCbGOw lCfGRItKZr7XA== From: Namhyung Kim To: Peter Zijlstra , Ingo Molnar Cc: Kan Liang , Mark Rutland , Alexander Shishkin , Arnaldo Carvalho de Melo , LKML , Stephane Eranian , Ravi Bangoria , Sandipan Das Subject: [PATCH v5 0/2] perf: Relax privilege restriction on AMD IBS Date: Mon, 28 Oct 2024 13:01:51 -0700 Message-ID: <20241028200153.1466731-1-namhyung@kernel.org> X-Mailer: git-send-email 2.47.0.163.g1226f6d8fa-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 v5 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. v5 changes) * 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(-) -- 2.47.0.163.g1226f6d8fa-goog