[tip:x86/cache] x86/intel_rdt: Introduce new "exclusive" mode

From: tip-bot for Reinette Chatre
Date: Sat Jun 23 2018 - 08:11:36 EST


Commit-ID: 414dd2b4732949ddc972c2592a13c799434249c6
Gitweb: https://git.kernel.org/tip/414dd2b4732949ddc972c2592a13c799434249c6
Author: Reinette Chatre <reinette.chatre@xxxxxxxxx>
AuthorDate: Fri, 22 Jun 2018 15:42:00 -0700
Committer: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
CommitDate: Sat, 23 Jun 2018 13:03:42 +0200

x86/intel_rdt: Introduce new "exclusive" mode

At the moment all allocations are shareable. There is no way for a user to
designate that an allocation associated with a resource group cannot be
shared by another.

Introduce the new mode "exclusive". When a resource group is marked as such
it implies that no overlap is allowed between its allocation and that of
another resource group.

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/f6d24672a4280fe3b24cd2da9b5f50214439c1af.1529706536.git.reinette.chatre@xxxxxxxxx

---
arch/x86/kernel/cpu/intel_rdt.h | 2 ++
arch/x86/kernel/cpu/intel_rdt_rdtgroup.c | 1 +
2 files changed, 3 insertions(+)

diff --git a/arch/x86/kernel/cpu/intel_rdt.h b/arch/x86/kernel/cpu/intel_rdt.h
index f2fbf4059b3f..c9033fd774d5 100644
--- a/arch/x86/kernel/cpu/intel_rdt.h
+++ b/arch/x86/kernel/cpu/intel_rdt.h
@@ -83,6 +83,7 @@ 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
*
* The mode of a resource group enables control over the allowed overlap
* between allocations associated with different resource groups (classes
@@ -91,6 +92,7 @@ enum rdt_group_type {
*/
enum rdtgrp_mode {
RDT_MODE_SHAREABLE = 0,
+ RDT_MODE_EXCLUSIVE,

/* 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 80ac09cf978b..910febef55e8 100644
--- a/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c
+++ b/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c
@@ -161,6 +161,7 @@ enum rdtgrp_mode rdtgroup_mode_by_closid(int closid)

static const char * const rdt_mode_str[] = {
[RDT_MODE_SHAREABLE] = "shareable",
+ [RDT_MODE_EXCLUSIVE] = "exclusive",
};

/**