[tip:x86/cache] x86/intel_rdt: Introduce the Cache Pseudo-Locking modes

[tip-bot for Reinette Chatre]

Commit-ID:  f438e62bcabd3e616b6280d422c5ba1c70b37f44
Gitweb:     https://git.kernel.org/tip/f438e62bcabd3e616b6280d422c5ba1c70b37f44
Author:     Reinette Chatre <reinette.chatre@xxxxxxxxx>
AuthorDate: Tue, 29 May 2018 05:57:41 -0700
Committer:  Thomas Gleixner <tglx@xxxxxxxxxxxxx>
CommitDate: Wed, 20 Jun 2018 00:56:33 +0200

x86/intel_rdt: Introduce the Cache Pseudo-Locking modes

The two modes used to manage Cache Pseudo-Locked regions are introduced.  A
resource group is assigned "pseudo-locksetup" mode when the user indicates
that this resource group will be used for a Cache Pseudo-Locked
region. When the Cache Pseudo-Locked region has been set up successfully
after the user wrote the requested schemata to the "schemata" file, then
the mode will automatically changed to "pseudo-locked".  The user is not
able to modify the mode to "pseudo-locked" by writing "pseudo-locked" to
the "mode" file directly.

Signed-off-by: Reinette Chatre <reinette.chatre@xxxxxxxxx>
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: fenghua.yu@xxxxxxxxx
Cc: tony.luck@xxxxxxxxx
Cc: vikas.shivappa@xxxxxxxxxxxxxxx
Cc: gavin.hindman@xxxxxxxxx
Cc: jithu.joseph@xxxxxxxxx
Cc: dave.hansen@xxxxxxxxx
Cc: hpa@xxxxxxxxx
Link: https://lkml.kernel.org/r/6ab82fb595f4b0ffa305dc204255b921eed51de7.1527593970.git.reinette.chatre@xxxxxxxxx

---
 arch/x86/kernel/cpu/intel_rdt.h          | 10 ++++++++++
 arch/x86/kernel/cpu/intel_rdt_rdtgroup.c | 13 +++++++++++--
 2 files changed, 21 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kernel/cpu/intel_rdt.h b/arch/x86/kernel/cpu/intel_rdt.h
index 8bbb047bf37c..bda87f5ef7bc 100644
--- a/arch/x86/kernel/cpu/intel_rdt.h
+++ b/arch/x86/kernel/cpu/intel_rdt.h
@@ -84,15 +84,25 @@ enum rdt_group_type {
  * enum rdtgrp_mode - Mode of a RDT resource group
  * @RDT_MODE_SHAREABLE: This resource group allows sharing of its allocations
  * @RDT_MODE_EXCLUSIVE: No sharing of this resource group's allocations allowed
+ * @RDT_MODE_PSEUDO_LOCKSETUP: Resource group will be used for Pseudo-Locking
+ * @RDT_MODE_PSEUDO_LOCKED: No sharing of this resource group's allocations
+ *                          allowed AND the allocations are Cache Pseudo-Locked
  *
  * The mode of a resource group enables control over the allowed overlap
  * between allocations associated with different resource groups (classes
  * of service). User is able to modify the mode of a resource group by
  * writing to the "mode" resctrl file associated with the resource group.
+ *
+ * The "shareable", "exclusive", and "pseudo-locksetup" modes are set by
+ * writing the appropriate text to the "mode" file. A resource group enters
+ * "pseudo-locked" mode after the schemata is written while the resource
+ * group is in "pseudo-locksetup" mode.
  */
 enum rdtgrp_mode {
 	RDT_MODE_SHAREABLE = 0,
 	RDT_MODE_EXCLUSIVE,
+	RDT_MODE_PSEUDO_LOCKSETUP,
+	RDT_MODE_PSEUDO_LOCKED,
 
 	/* Must be last */
 	RDT_NUM_MODES,
diff --git a/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c b/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c
index 7d63380abe02..9e69f4dbc686 100644
--- a/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c
+++ b/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c
@@ -161,8 +161,10 @@ enum rdtgrp_mode rdtgroup_mode_by_closid(int closid)
 }
 
 static const char * const rdt_mode_str[] = {
-	[RDT_MODE_SHAREABLE]	= "shareable",
-	[RDT_MODE_EXCLUSIVE]	= "exclusive",
+	[RDT_MODE_SHAREABLE]		= "shareable",
+	[RDT_MODE_EXCLUSIVE]		= "exclusive",
+	[RDT_MODE_PSEUDO_LOCKSETUP]	= "pseudo-locksetup",
+	[RDT_MODE_PSEUDO_LOCKED]	= "pseudo-locked",
 };
 
 /**
@@ -759,6 +761,13 @@ static int rdt_bit_usage_show(struct kernfs_open_file *of,
 			case RDT_MODE_EXCLUSIVE:
 				exclusive |= *ctrl;
 				break;
+			/*
+			 * Temporarily handle pseudo-locking enums
+			 * to silence compile warnings until handling
+			 * added in later patches.
+			 */
+			case RDT_MODE_PSEUDO_LOCKSETUP:
+			case RDT_MODE_PSEUDO_LOCKED:
 			case RDT_NUM_MODES:
 				WARN(1,
 				     "invalid mode for closid %d\n", i);