[tip:x86/cache] x86/intel_rdt: Add command line parameter to control L2_CDP

[tip-bot for Fenghua Yu]

Commit-ID:  31516de306c0c9235156cdc7acb976ea21f1f646
Gitweb:     https://git.kernel.org/tip/31516de306c0c9235156cdc7acb976ea21f1f646
Author:     Fenghua Yu <fenghua.yu@xxxxxxxxx>
AuthorDate: Wed, 20 Dec 2017 14:57:24 -0800
Committer:  Thomas Gleixner <tglx@xxxxxxxxxxxxx>
CommitDate: Thu, 18 Jan 2018 09:33:32 +0100

x86/intel_rdt: Add command line parameter to control L2_CDP

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@xxxxxxxxx>
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: "Ravi V Shankar" <ravi.v.shankar@xxxxxxxxx>
Cc: "Tony Luck" <tony.luck@xxxxxxxxx>
Cc: Vikas" <vikas.shivappa@xxxxxxxxx>
Cc: Sai Praneeth" <sai.praneeth.prakhya@xxxxxxxxx>
Cc: Reinette" <reinette.chatre@xxxxxxxxx>
Link: https://lkml.kernel.org/r/1513810644-78015-7-git-send-email-fenghua.yu@xxxxxxxxx


---
 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 46b26bf..fde058c 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 5202da0..410629f 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 @@ static struct rdt_options rdt_options[]  __initdata = {
 	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)