From: Fenghua Yu <fenghua.yu@intel.com>
Date: Wed, 20 Dec 2017 14:57:24 -0800
Subject: x86/intel_rdt: Add command line parameter to control L2_CDP
Git-commit: 31516de306c0c9235156cdc7acb976ea21f1f646
Patch-mainline: v4.16-rc1
References: fate#325152
L2 CDP can be controlled by kernel parameter "rdt=".
If "rdt=l2cdp", L2 CDP is turned on.
If "rdt=!l2cdp", L2 CDP is turned off.
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: "Ravi V Shankar" <ravi.v.shankar@intel.com>
Cc: "Tony Luck" <tony.luck@intel.com>
Cc: Vikas" <vikas.shivappa@intel.com>
Cc: Sai Praneeth" <sai.praneeth.prakhya@intel.com>
Cc: Reinette" <reinette.chatre@intel.com>
Link: https://lkml.kernel.org/r/1513810644-78015-7-git-send-email-fenghua.yu@intel.com
Acked-by: Borislav Petkov <bp@suse.de>
---
Documentation/admin-guide/kernel-parameters.txt | 3 ++-
arch/x86/kernel/cpu/intel_rdt.c | 2 ++
2 files changed, 4 insertions(+), 1 deletion(-)
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 46b26bfee27b..fde058ca8419 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -3682,7 +3682,8 @@
rdt= [HW,X86,RDT]
Turn on/off individual RDT features. List is:
- cmt, mbmtotal, mbmlocal, l3cat, l3cdp, l2cat, mba.
+ cmt, mbmtotal, mbmlocal, l3cat, l3cdp, l2cat, l2cdp,
+ mba.
E.g. to turn on cmt and turn off mba use:
rdt=cmt,!mba
diff --git a/arch/x86/kernel/cpu/intel_rdt.c b/arch/x86/kernel/cpu/intel_rdt.c
index 5202da08fd6f..410629f10ad3 100644
--- a/arch/x86/kernel/cpu/intel_rdt.c
+++ b/arch/x86/kernel/cpu/intel_rdt.c
@@ -691,6 +691,7 @@ enum {
RDT_FLAG_L3_CAT,
RDT_FLAG_L3_CDP,
RDT_FLAG_L2_CAT,
+ RDT_FLAG_L2_CDP,
RDT_FLAG_MBA,
};
@@ -713,6 +714,7 @@ struct rdt_options {
RDT_OPT(RDT_FLAG_L3_CAT, "l3cat", X86_FEATURE_CAT_L3),
RDT_OPT(RDT_FLAG_L3_CDP, "l3cdp", X86_FEATURE_CDP_L3),
RDT_OPT(RDT_FLAG_L2_CAT, "l2cat", X86_FEATURE_CAT_L2),
+ RDT_OPT(RDT_FLAG_L2_CDP, "l2cdp", X86_FEATURE_CDP_L2),
RDT_OPT(RDT_FLAG_MBA, "mba", X86_FEATURE_MBA),
};
#define NUM_RDT_OPTIONS ARRAY_SIZE(rdt_options)