The following commit has been merged into the x86/cache branch of tip:

Commit-ID:     bebf57bf054b561a62f3440142b2eddab2b0bbff
Gitweb:        https://git.kernel.org/tip/bebf57bf054b561a62f3440142b2eddab2b0bbff
Author:        Babu Moger <babu.moger@amd.com>
AuthorDate:    Fri, 05 Sep 2025 16:34:05 -05:00
Committer:     Borislav Petkov (AMD) <bp@alien8.de>
CommitterDate: Mon, 15 Sep 2025 12:05:23 +02:00

x86/resctrl: Add ABMC feature in the command line options

Add a kernel command-line parameter to enable or disable the exposure of
the ABMC (Assignable Bandwidth Monitoring Counters) hardware feature to
resctrl.

Signed-off-by: Babu Moger <babu.moger@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Link: https://lore.kernel.org/cover.1757108044.git.babu.moger@amd.com
---
 Documentation/admin-guide/kernel-parameters.txt | 2 +-
 Documentation/filesystems/resctrl.rst           | 1 +
 arch/x86/kernel/cpu/resctrl/core.c              | 2 ++
 3 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 5a7a83c..889e68e 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -6155,7 +6155,7 @@
 	rdt=		[HW,X86,RDT]
 			Turn on/off individual RDT features. List is:
 			cmt, mbmtotal, mbmlocal, l3cat, l3cdp, l2cat, l2cdp,
-			mba, smba, bmec.
+			mba, smba, bmec, abmc.
 			E.g. to turn on cmt and turn off mba use:
 				rdt=cmt,!mba
 
diff --git a/Documentation/filesystems/resctrl.rst b/Documentation/filesystems/resctrl.rst
index c7949dd..c97fd77 100644
--- a/Documentation/filesystems/resctrl.rst
+++ b/Documentation/filesystems/resctrl.rst
@@ -26,6 +26,7 @@ MBM (Memory Bandwidth Monitoring)		"cqm_mbm_total", "cqm_mbm_local"
 MBA (Memory Bandwidth Allocation)		"mba"
 SMBA (Slow Memory Bandwidth Allocation)         ""
 BMEC (Bandwidth Monitoring Event Configuration) ""
+ABMC (Assignable Bandwidth Monitoring Counters) ""
 ===============================================	================================
 
 Historically, new features were made visible by default in /proc/cpuinfo. This
diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index fbf019c..b07b12a 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -711,6 +711,7 @@ enum {
 	RDT_FLAG_MBA,
 	RDT_FLAG_SMBA,
 	RDT_FLAG_BMEC,
+	RDT_FLAG_ABMC,
 };
 
 #define RDT_OPT(idx, n, f)	\
@@ -736,6 +737,7 @@ static struct rdt_options rdt_options[]  __ro_after_init = {
 	RDT_OPT(RDT_FLAG_MBA,	    "mba",	X86_FEATURE_MBA),
 	RDT_OPT(RDT_FLAG_SMBA,	    "smba",	X86_FEATURE_SMBA),
 	RDT_OPT(RDT_FLAG_BMEC,	    "bmec",	X86_FEATURE_BMEC),
+	RDT_OPT(RDT_FLAG_ABMC,	    "abmc",	X86_FEATURE_ABMC),
 };
 #define NUM_RDT_OPTIONS ARRAY_SIZE(rdt_options)