From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pl1-f180.google.com (mail-pl1-f180.google.com [209.85.214.180]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1DE104878E for ; Fri, 8 Dec 2023 19:22:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="dY2cPynp" Received: by mail-pl1-f180.google.com with SMTP id d9443c01a7336-1d1d307bbb3so18805ad.0 for ; Fri, 08 Dec 2023 11:22:44 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1702063364; x=1702668164; darn=lists.linux.dev; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:from:to:cc:subject:date :message-id:reply-to; bh=gZ30NYGkjbX21PN8dBphQWbz/hwhfTyVX43/tAQx5MY=; b=dY2cPynpg530EOA/7lAEf0bkVGWkr8B3X7Qk7r1ew35ChvJk5ofmPfo4/9LKqm3hkh 3Ba0OTSvnD0x+0iAPrhELwpjVzzcG2vviU+DUZVXl6UusuMO1Fd4dSea0q3e1+FxvvLJ bxy3fWU+2Mf1BISnsNTgkI1Nmgo1asVGZGDkJNHuWTLHZKq5knDbqlZCF+A5USXF11LR EUpssbrrJvigrOWz1NopFyqAdpvz0m4VRoViBYt/HiPLJqypMfVUFsRRwTphKwbTmjt3 qLsq1InQKTMJWBATwStv/r5mRGP1R4wpSGpTyllpqU+WIjkyjCE63mpj+cHe/IOIIyqn Bo9g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1702063364; x=1702668164; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=gZ30NYGkjbX21PN8dBphQWbz/hwhfTyVX43/tAQx5MY=; b=ZfF/kaiyYcN8iX5NF4eqXXO77936I7pHRte9r0NdgE+Vl/uXh/k1wgw5xyEY6ccilZ hSdFynt2rjg94GsKC/Q3t7YOmFum4JZh060nYKcyGawxBel0dcZoKy/xh62ir20QvYa6 nT49rBTDwDt4Kj81BsRtRKprXSNDp0rJMkAh10eAvDCWFLrU6Gafc89vf5qIenfmC94u NON8r9WTCcTX68Cp7sMx2vrWz0DVNXkFrvvZlxfUgPnJQUZ4QD69N/SjK/Sz306ARkkr B4pewjy73OwTmgeJQzdesNY9tvBhkplQFEVqADG5NfeDQLUXGWycv+W3uRQ0+U4H/gbL I2tQ== X-Gm-Message-State: AOJu0Yy98fDj8tnRqGeKl2ok44FPHciDg4mBatDouXdVZrmx0aeVFQJ/ fY6bhKo6dF5Zhs2kX4+Rcw9O4uw/CmKSJTtLN1N2yw== X-Google-Smtp-Source: AGHT+IGasWbbXvVDHLeMypAYC8mh/pLHr897bAE6/ckWJyPBsRxFn+J1youQDVPIKNs88w/EVxdL10enFiyIBoZk4VI= X-Received: by 2002:a17:902:e881:b0:1d0:4548:97ff with SMTP id w1-20020a170902e88100b001d0454897ffmr195882plg.13.1702063364214; Fri, 08 Dec 2023 11:22:44 -0800 (PST) Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 References: <20231201214737.104444-1-tony.luck@intel.com> <20231207195613.153980-1-tony.luck@intel.com> <20231207195613.153980-4-tony.luck@intel.com> In-Reply-To: <20231207195613.153980-4-tony.luck@intel.com> From: Peter Newman Date: Fri, 8 Dec 2023 11:22:33 -0800 Message-ID: Subject: Re: [PATCH v6 3/3] x86/resctrl: Add new "mba_MBps_event" mount option to documentation To: Tony Luck Cc: Fenghua Yu , Reinette Chatre , Jonathan Corbet , Shuah Khan , x86@kernel.org, Shaopeng Tan , James Morse , Jamie Iles , Babu Moger , Randy Dunlap , linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, patches@lists.linux.dev Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Thu, Dec 7, 2023 at 11:56=E2=80=AFAM Tony Luck wro= te: > > New mount option may be used to choose a specific memory bandwidth > monitoring event to feed the MBA Software Controller(mba_sc) feedback > loop. > > Signed-off-by: Tony Luck > --- > Documentation/arch/x86/resctrl.rst | 16 ++++++++++++++-- > 1 file changed, 14 insertions(+), 2 deletions(-) > > diff --git a/Documentation/arch/x86/resctrl.rst b/Documentation/arch/x86/= resctrl.rst > index a6279df64a9d..a0c521db6786 100644 > --- a/Documentation/arch/x86/resctrl.rst > +++ b/Documentation/arch/x86/resctrl.rst > @@ -35,7 +35,8 @@ about the feature from resctrl's info directory. > > To use the feature mount the file system:: > > - # mount -t resctrl resctrl [-o cdp[,cdpl2][,mba_MBps][,debug]] /sys/fs/= resctrl > + # mount -t resctrl resctrl [-o cdp[,cdpl2][,mba_MBps] \ > + [,mba_MBps_event=3D[mbm_local_bytes|mbm_total_bytes]][,debug]] /sys/fs/= resctrl > > mount options are: > > @@ -45,7 +46,12 @@ mount options are: > Enable code/data prioritization in L2 cache allocations. > "mba_MBps": > Enable the MBA Software Controller(mba_sc) to specify MBA > - bandwidth in MBps > + bandwidth in MBps. Defaults to using MBM local bandwidth, > + but will use total bandwidth on systems that do not support > + local bandwidth monitoring. > +"mba_MBps_event=3D[mbm_local_bytes|mbm_total_bytes]": > + Enable the MBA Software Controller(mba_sc) with a specific > + MBM event as input to the feedback loop. > "debug": > Make debug files accessible. Available debug files are annotated = with > "Available only with debug option". > @@ -538,6 +544,12 @@ where as user can switch to the "MBA software contro= ller" mode using > a mount option 'mba_MBps'. The schemata format is specified in the below > sections. > > +By default the software feedback mechanism uses measurement of local > +memory bandwidth to make adjustments to throttling levels. If a system > +is running applications with poor NUMA locality users may want to use > +the "mba_MBps_event=3Dmbm_total_bytes" mount option which will use total > +memory bandwidth measurements instead of local. > + > L3 schemata file details (code and data prioritization disabled) > ---------------------------------------------------------------- > With CDP disabled the L3 schemata format is:: > -- > 2.41.0 > for content: Reviewed-by: Peter Newman