From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793654535; b=HchGx2GcXoWNhEWET3fFVSM8kLnySCcTYEF1qp4Jrn5UIleeprJrd+YLxN6YBToKm/vP 4XjYJU8FDAxu3hQlLYZ+4HTB7VM8hcvPuCBWrDXY6TUrnfhBNQTaUBJB4XxAkB0FpmWsG J6xDoCtsvYBQazmVEmweri28GXOZtcoiadxveo/VQtseQUV9SnxeoAvFhwH8/WlB9ueRb ZM601mjBBPZdrVZkIDefIwDvV5MuJ+82ho9WXK9K59kKzxZBD4OLU4RPGBn01Ne3nv5YJ QXI+/HxUtjJ4EQi1h4TW8/adn86/6B9rU33/epvWoQfRyKqiQLsZIE1+zonr3XTZ6kA== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793654535; h=Received:DKIM-Signature:Message-ID:From:Subject:Reply-To:To:Cc: In-Reply-To:References:Content-Type:Content-Transfer-Encoding:Date; bh=bJHRXh2RtxnFiB8irCpfoG3TotdBuywUjxkTgtgxy2Y=; b=cvGmmY/hYr4WTQOdQ99E96bHfRFziv4cKr9rRtEpFBLjMmVtoICDm3m4+Mx44yFZjB4e ddKubkt76g+B+fef/cE4ZYfxRsOxNdX/yG19Rqm/YaY54rfO7q/wNZ4QQlqyIqyOxOvYj Q2mFvwzcQSIhglxotV444ccsi+dQ0SgU2X1aDh5awpEDu92NU5c6ygPOK6PAHTFO2DMUT 8KJ1jKtOsiWg5mUH7MlzEoQhu5p//HJsDDWgL+Tj5a56H/i16alKJTtA0JUI+JiAPtwgn bBsvdRclfdzdV3zLsD++N9bes7VAtiEUuxrKJaZ/R/C5BYwOLOEm/qgvyCWU8XeALOw== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=asxYvhxo; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2D9E2606A324 for ; Mon, 2 Nov 2026 21:22:14 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=asxYvhxo Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9BE7F1F00A16; Mon, 2 Nov 2026 21:22:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793654534; bh=bJHRXh2RtxnFiB8irCpfoG3TotdBuywUjxkTgtgxy2Y=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=asxYvhxoeOnX8y3NkulwlzS9f3STvMg5hKC5FM+3RMdS/U26CG15F9jKdtWpgB1l8 v+mgjldtmddxpnZ/DFmikBDbJ7+U/a1drvCDXTf8eLkK6MGc1ctBiLHADOe5e3DZZF 9tvEK+HFGjcNd+bJuweJT0D3RqqR0YvQYkBtdpwL8f/sdnuIBSmtO5ixtgzIJubjh3 uCchGKP/lwCzWFfVyLXUt/JjCCfMwF3Vjx14MewIr1KPcw4GtxOyclqfWpWZCCCiE8 jSLd56d11YJTq8TeQoxgAOu/JkaoLvdXp4Dsw9JjcmuhA9fkAq95Da5dSn0+qDMo1u BTg562PQnaAHw== Message-ID: From: sashiko-bot@kernel.org Subject: Re: [PATCH v2 1/2] perf jevents: add iommu page table walk metrics Reply-To: sashiko-reviews@lists.linux.dev To: "Jacob Lefkowitz" Cc: linux-perf-users@vger.kernel.org In-Reply-To: <20261102-perf-tools-next-v2-1-4d237f886710@akamai.com> References: <20261102-perf-tools-next-v2-0-4d237f886710@akamai.com> <20261102-perf-tools-next-v2-1-4d237f886710@akamai.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Mon, 02 Nov 2026 21:22:14 +0000 X-Mailing-List: linux-perf-users@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list > From: Jacob Lefkowitz >=20 > Adds page table walk metrics specfically to perf jevents for AMD > platforms to enhance observability into IOMMU overhead. The metrics > are supported on Zen 2 and neweer processors. They are implemented > using the amd_iommu PMU events. >=20 > The list of metrics added here are: > - lpm_iommu_ptw_reads_per_tlb_miss > - lpm_iommu_ptw_nested_read_ratio > - lpm_iommu_ptw_guest_read_ratio > - lpm_iommu_trans_per_sec >=20 > The changes here have been tested with 'sleep 10' as the workload: >=20 > perf stat -M iommuptw --per-socket --metric-only -j -a -- sleep 10 > {"socket" : "S0", "counters" : 8, > "reads/tlb_miss lpm_iommu_ptw_reads_per_tlb_miss" : "0.5", > "% lpm_iommu_ptw_nested_read_ratio" : "none", > "% lpm_iommu_ptw_guest_read_ratio" : "0.0", > "trans/s lpm_iommu_trans_per_sec" : "971.5"} > {"socket" : "S1", "counters" : 0, > "reads/tlb_miss lpm_iommu_ptw_reads_per_tlb_miss" : "none", > "% lpm_iommu_ptw_nested_read_ratio" : "none", > "% lpm_iommu_ptw_guest_read_ratio" : "none, > "trans/s lpm_iommu_trans_per_sec" : "none"} >=20 > Signed-off-by: Jacob Lefkowitz Sashiko has reviewed this patch and found no issues. --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20261102-perf-tools= -next-v2-0-4d237f886710@akamai.com?part=3D1