From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.19]) (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 C0A7A1862A; Thu, 14 Nov 2024 00:17:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.19 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731543445; cv=none; b=pXT2MMfpwZna8vmOI0hYHn6KfwFb8fLMhVBVNXEK6YnV32RyX16h7Q3yqmZHhlrPaOq0HTZ4lL7dC18apbwFIdKSD1hKVVuqHKmMMelwmTwwLBchi9shFC5V1G3eu2/jqYDcPoVDsSdN02K/ekqTwOv+S8bcDgarp6QuXQ17wlM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731543445; c=relaxed/simple; bh=GIBBPueD41f/gJbHQyFVQ4yIOZGadcuF/ZE+ZTaWWqc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=ZMF7oEqH7bBsprTBrj4K5khgKdixUBHLmfHUxtkvOQH68oBcCMT5RFYT6fqhD+isU7oO/UyN2s8r69a2molMNknUxpOV9IuN47d6ubHESFkHaGVZayVKAMbyL2V1LHprhWPWY9N53j74ugUJ8i2YZGA6uYyW5GgKx0iWvF4Lo5w= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com; spf=pass smtp.mailfrom=intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=ipxUWFwV; arc=none smtp.client-ip=192.198.163.19 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="ipxUWFwV" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1731543444; x=1763079444; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=GIBBPueD41f/gJbHQyFVQ4yIOZGadcuF/ZE+ZTaWWqc=; b=ipxUWFwVpWD0cdQ/nVrwHbDrdUGlpbbvb1ZkMpgTYJqM7eewpYp0zqwU 18/rRmkfaefsbmC01P6KeyjMfU/aWvzfKkYCTayhxT5BaPal0HLTIROzp D7mhcB0vwG7n3Pq125b6XlnOFXBCj0YHyRtRtjH/FMbNWEz9EyZ6ifm1o 32YyeAW9ceH+KLAlNpIDiuEksvytQSD4hlON2Rv1Lah1IUWeoib+7MBUI ffxopdxLBQ1AIQvTszZr3WgMa+P2uH0Rci920DKWu4iZITt8xuo0hfG+Q DEcVTGh441AO1+bUG7YRgNBDrIG/EZpvtEDr3sPBezCi4GyDf5cCzVAvL Q==; X-CSE-ConnectionGUID: Wm+x/8MoQKK66ZgpZb0TzA== X-CSE-MsgGUID: BeiUS6hZQOG2mGZ9Q8skzA== X-IronPort-AV: E=McAfee;i="6700,10204,11255"; a="30869529" X-IronPort-AV: E=Sophos;i="6.12,152,1728975600"; d="scan'208";a="30869529" Received: from fmviesa003.fm.intel.com ([10.60.135.143]) by fmvoesa113.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Nov 2024 16:17:18 -0800 X-CSE-ConnectionGUID: dAGrj+e/QTeHbfwF+6rOeQ== X-CSE-MsgGUID: AXTdSrBDQNiZGzAmRXtJ9g== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.12,152,1728975600"; d="scan'208";a="92081169" Received: from agluck-desk3.sc.intel.com ([172.25.222.70]) by fmviesa003-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Nov 2024 16:17:19 -0800 From: Tony Luck To: Fenghua Yu , Reinette Chatre , Peter Newman , Jonathan Corbet , x86@kernel.org Cc: James Morse , Jamie Iles , Babu Moger , Randy Dunlap , "Shaopeng Tan (Fujitsu)" , linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, patches@lists.linux.dev, Tony Luck Subject: [PATCH v9 7/9] x86/resctrl: Add write option to "mba_MBps_event" file Date: Wed, 13 Nov 2024 16:17:09 -0800 Message-ID: <20241114001712.80315-8-tony.luck@intel.com> X-Mailer: git-send-email 2.47.0 In-Reply-To: <20241114001712.80315-1-tony.luck@intel.com> References: <20241114001712.80315-1-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-Transfer-Encoding: 8bit The "mba_MBps" mount option provides an alternate method to control memory bandwidth. Instead of specifying allowable bandwidth as a percentage of maximum possible, the user provides a MiB/s limit value. Historically the limit was enforced by a feedback loop from the measure local bandwidth to adjust the memory bandwidth allocation controls. There is a file in each ctrl_mon group directory that shows the event currently in use (always says "mbm_local_bytes"). Allow writing that file to choose a different event. A user can choose any of the memory bandwidth monitoring events listed in /sys/fs/resctrl/info/L3_mon/mon_features independently for each ctrl_mon group by writing to the "mba_MBps_event" file. Signed-off-by: Tony Luck --- arch/x86/kernel/cpu/resctrl/internal.h | 2 ++ arch/x86/kernel/cpu/resctrl/ctrlmondata.c | 40 +++++++++++++++++++++++ arch/x86/kernel/cpu/resctrl/rdtgroup.c | 3 +- 3 files changed, 44 insertions(+), 1 deletion(-) diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h index ce10a883ecf8..6345ab3e0890 100644 --- a/arch/x86/kernel/cpu/resctrl/internal.h +++ b/arch/x86/kernel/cpu/resctrl/internal.h @@ -609,6 +609,8 @@ ssize_t rdtgroup_schemata_write(struct kernfs_open_file *of, char *buf, size_t nbytes, loff_t off); int rdtgroup_schemata_show(struct kernfs_open_file *of, struct seq_file *s, void *v); +ssize_t rdtgroup_mba_mbps_event_write(struct kernfs_open_file *of, + char *buf, size_t nbytes, loff_t off); int rdtgroup_mba_mbps_event_show(struct kernfs_open_file *of, struct seq_file *s, void *v); bool rdtgroup_cbm_overlaps(struct resctrl_schema *s, struct rdt_ctrl_domain *d, diff --git a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c index 5fa37b4ecc7a..ee983b68c046 100644 --- a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c +++ b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c @@ -518,6 +518,46 @@ static int smp_mon_event_count(void *arg) return 0; } +ssize_t rdtgroup_mba_mbps_event_write(struct kernfs_open_file *of, + char *buf, size_t nbytes, loff_t off) +{ + struct rdtgroup *rdtgrp; + int ret = 0; + + /* Valid input requires a trailing newline */ + if (nbytes == 0 || buf[nbytes - 1] != '\n') + return -EINVAL; + buf[nbytes - 1] = '\0'; + + rdtgrp = rdtgroup_kn_lock_live(of->kn); + if (!rdtgrp) { + rdtgroup_kn_unlock(of->kn); + return -ENOENT; + } + rdt_last_cmd_clear(); + + if (!strcmp(buf, "mbm_local_bytes")) { + if (is_mbm_local_enabled()) + rdtgrp->mba_mbps_event = QOS_L3_MBM_LOCAL_EVENT_ID; + else + ret = -EINVAL; + } else if (!strcmp(buf, "mbm_total_bytes")) { + if (is_mbm_total_enabled()) + rdtgrp->mba_mbps_event = QOS_L3_MBM_TOTAL_EVENT_ID; + else + ret = -EINVAL; + } else { + ret = -EINVAL; + } + + if (ret) + rdt_last_cmd_printf("Unsupported event id '%s'\n", buf); + + rdtgroup_kn_unlock(of->kn); + + return ret ?: nbytes; +} + int rdtgroup_mba_mbps_event_show(struct kernfs_open_file *of, struct seq_file *s, void *v) { diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c index 416e1acfad9f..3f2e035208e6 100644 --- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c +++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c @@ -1945,8 +1945,9 @@ static struct rftype res_common_files[] = { }, { .name = "mba_MBps_event", - .mode = 0444, + .mode = 0644, .kf_ops = &rdtgroup_kf_single_ops, + .write = rdtgroup_mba_mbps_event_write, .seq_show = rdtgroup_mba_mbps_event_show, }, { -- 2.47.0