From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (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 A5B4E1D6A8 for ; Wed, 25 Oct 2023 20:52:42 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="TGq8NBDO" Received: from mgamail.intel.com (mgamail.intel.com [192.55.52.115]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8CC81136; Wed, 25 Oct 2023 13:52:40 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1698267160; x=1729803160; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=XTbrElkU1MbX6ZrhPb1QYOzV1U9Co1VHsj67ZR6GG3g=; b=TGq8NBDOml6EemXEi9z6ISE3nVI291MD184rYq3x5nMy8II6Rtc3wLc8 dqzEzUlUyooxAfoTwlze/vcXw3VWYMETeDKLtijq7NTkm6hl/QPhzbcjc H6Hmjsz19ZJZsEvazEQPvGQiuDB7SXQ63bJA3hfQwD3itZiF62lv323gi t8NhIT1/qb0aJW/U4ClFOeM6kbhzTvYwUD/FyFKAbOdiX+3cbYsx2UPB+ 9InzzXxYCOsvVfU+cgZWNEx3MPzlvrhSJ2tkNDmmD+2IGTJVge7uK5CaU /z5bc536Sa/KoiQdt6MrrMAwQC7I/qpqagxbX0LEiQLrV7ZZWoWO908K6 Q==; X-IronPort-AV: E=McAfee;i="6600,9927,10874"; a="387222339" X-IronPort-AV: E=Sophos;i="6.03,250,1694761200"; d="scan'208";a="387222339" Received: from orsmga003.jf.intel.com ([10.7.209.27]) by fmsmga103.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 25 Oct 2023 13:52:39 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10874"; a="708817429" X-IronPort-AV: E=Sophos;i="6.03,250,1694761200"; d="scan'208";a="708817429" Received: from agluck-desk3.sc.intel.com (HELO agluck-desk3) ([172.25.222.74]) by orsmga003-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 25 Oct 2023 13:52:38 -0700 Date: Wed, 25 Oct 2023 13:52:37 -0700 From: Tony Luck To: "Moger, Babu" Cc: Peter Newman , Fenghua Yu , Reinette Chatre , Jonathan Corbet , Shuah Khan , x86@kernel.org, Shaopeng Tan , James Morse , Jamie Iles , Randy Dunlap , linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, patches@lists.linux.dev Subject: Re: [PATCH] x86/resctrl: mba_MBps: Fall back to total b/w if local b/w unavailable Message-ID: References: <20231024181600.8270-1-tony.luck@intel.com> Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Wed, Oct 25, 2023 at 03:42:14PM -0500, Moger, Babu wrote: > I meant, I was thinking bit different. > > > > > You need these changes in only two functions, mbm_bw_count and > > update_mba_bw. You decide which event you want to use based on availability, > > > > Something like this. I updated mbm_bw_count. > > > > diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c > > b/arch/x86/kernel/cpu/resctrl/monitor.c > > index 0ad23475fe16..302993e4fbc3 100644 > > --- a/arch/x86/kernel/cpu/resctrl/monitor.c > > +++ b/arch/x86/kernel/cpu/resctrl/monitor.c > > @@ -436,8 +436,16 @@ static int __mon_event_count(u32 rmid, struct > > rmid_read *rr) > > */ > > static void mbm_bw_count(u32 rmid, struct rmid_read *rr) > > { > > - struct mbm_state *m = &rr->d->mbm_local[rmid]; > > u64 cur_bw, bytes, cur_bytes; > > + struct mbm_state *m; > > + int evtid; > > + > > + if (is_mbm_local_enabled()) > > + evtid = QOS_L3_MBM_LOCAL_EVENT_ID; > > + else > > + evtid = QOS_L3_MBM_TOTAL_EVENT_ID; > > + > > + m = get_mbm_state(rr->d, rmid, evtid); Ok. Yes. That seems simpler. Maybe I should just set a global "mbm_evtid" at mount time. No need to check every time to see if is_mbm_local_enabled() somehow changed and local b/w measurements were suddenly available! -Tony