linux-kernel - [PATCH v5 08/12] x86/resctrl: Add sysfs interface to read mbm_local

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <166431038771.373387.9706240777220251603.stgit@bmoger-ubuntu>
Date:   Tue, 27 Sep 2022 15:26:27 -0500
From:   Babu Moger <babu.moger@....com>
To:     <corbet@....net>, <reinette.chatre@...el.com>,
        <tglx@...utronix.de>, <mingo@...hat.com>, <bp@...en8.de>
CC:     <fenghua.yu@...el.com>, <dave.hansen@...ux.intel.com>,
        <x86@...nel.org>, <hpa@...or.com>, <paulmck@...nel.org>,
        <akpm@...ux-foundation.org>, <quic_neeraju@...cinc.com>,
        <rdunlap@...radead.org>, <damien.lemoal@...nsource.wdc.com>,
        <songmuchun@...edance.com>, <peterz@...radead.org>,
        <jpoimboe@...nel.org>, <pbonzini@...hat.com>, <babu.moger@....com>,
        <chang.seok.bae@...el.com>, <pawan.kumar.gupta@...ux.intel.com>,
        <jmattson@...gle.com>, <daniel.sneddon@...ux.intel.com>,
        <sandipan.das@....com>, <tony.luck@...el.com>,
        <james.morse@....com>, <linux-doc@...r.kernel.org>,
        <linux-kernel@...r.kernel.org>, <bagasdotme@...il.com>,
        <eranian@...gle.com>
Subject: [PATCH v5 08/12] x86/resctrl: Add sysfs interface to read
 mbm_local_bytes event configuration

The current event configuration can be viewed by the user by reading
the configuration file /sys/fs/resctrl/info/L3_MON/mbm_local_config.

Following are the types of events supported:

====  ===========================================================
Bits   Description
====  ===========================================================
6      Dirty Victims from the QOS domain to all types of memory
5      Reads to slow memory in the non-local NUMA domain
4      Reads to slow memory in the local NUMA domain
3      Non-temporal writes to non-local NUMA domain
2      Non-temporal writes to local NUMA domain
1      Reads to memory in the non-local NUMA domain
0      Reads to memory in the local NUMA domain
====  ===========================================================

By default, the mbm_local_bytes configuration is set to 0x15 to count
all the local event types. The event configuration settings are domain
specific. Changing the configuration on one CPU in a domain would
affect the whole domain.

For example:
    $cat /sys/fs/resctrl/info/L3_MON/mbm_local_config
    0:0x15;1:0x15;2:0x15;3:0x15

    In this case the event mbm_local_bytes is currently configured with
    0x15 on domains 0 to 3.

Signed-off-by: Babu Moger <babu.moger@....com>
---
 arch/x86/kernel/cpu/resctrl/rdtgroup.c |   20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index b51fae77ba5c..27bf6ade0dbf 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -1481,6 +1481,16 @@ static int mbm_total_config_show(struct kernfs_open_file *of,
 	return 0;
 }
 
+static int mbm_local_config_show(struct kernfs_open_file *of,
+				 struct seq_file *seq, void *v)
+{
+	struct rdt_resource *r = of->kn->parent->priv;
+
+	mbm_config_show(seq, r, QOS_L3_MBM_LOCAL_EVENT_ID);
+
+	return 0;
+}
+
 /* rdtgroup information files for one cache resource. */
 static struct rftype res_common_files[] = {
 	{
@@ -1585,6 +1595,12 @@ static struct rftype res_common_files[] = {
 		.kf_ops		= &rdtgroup_kf_single_ops,
 		.seq_show	= mbm_total_config_show,
 	},
+	{
+		.name		= "mbm_local_config",
+		.mode		= 0644,
+		.kf_ops		= &rdtgroup_kf_single_ops,
+		.seq_show	= mbm_local_config_show,
+	},
 	{
 		.name		= "cpus",
 		.mode		= 0644,
@@ -1698,6 +1714,10 @@ void __init mbm_config_rftype_init(void)
 	rft = rdtgroup_get_rftype_by_name("mbm_total_config");
 	if (rft)
 		rft->fflags = RF_MON_INFO | RFTYPE_RES_CACHE;
+
+	rft = rdtgroup_get_rftype_by_name("mbm_local_config");
+	if (rft)
+		rft->fflags = RF_MON_INFO | RFTYPE_RES_CACHE;
 }
 
 /**