The HRESET instruction isolates the classification of individual
tasks when they run sequentially on the same logical processor. It resets
the classification history that the logical processor maintains.
Cc: Ben Segall <bsegall@google.com>
Cc: Daniel Bristot de Oliveira <bristot@redhat.com>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Ionela Voinescu <ionela.voinescu@arm.com>
Cc: Joel Fernandes (Google) <joel@joelfernandes.org>
Cc: Len Brown <len.brown@intel.com>
Cc: Lukasz Luba <lukasz.luba@arm.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Perry Yuan <Perry.Yuan@amd.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Tim C. Chen <tim.c.chen@intel.com>
Cc: Valentin Schneider <vschneid@redhat.com>
Cc: Zhao Liu <zhao1.liu@linux.intel.com>
Cc: x86@kernel.org
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
---
Changes since v3:
* Moved definition of HRESET to its correct leaf: CPUID_7_1_EAX (Zhao)
Changes since v2:
* None
Changes since v1:
* None
---
arch/x86/include/asm/cpufeatures.h | 1 +
arch/x86/include/asm/msr-index.h | 3 +++
2 files changed, 4 insertions(+)
diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h
index 98a84cbf4261..5edb63af2996 100644
--- a/arch/x86/include/asm/cpufeatures.h
+++ b/arch/x86/include/asm/cpufeatures.h
@@ -319,6 +319,7 @@
#define X86_FEATURE_FSRC (12*32+12) /* "" Fast short REP {CMPSB,SCASB} */
#define X86_FEATURE_LKGS (12*32+18) /* "" Load "kernel" (userspace) GS */
#define X86_FEATURE_AMX_FP16 (12*32+21) /* "" AMX fp16 Support */
+#define X86_FEATURE_HRESET (12*32+22) /* Hardware history reset instruction */
#define X86_FEATURE_AVX_IFMA (12*32+23) /* "" Support for VPMADD52[H,L]UQ */
#define X86_FEATURE_LAM (12*32+26) /* Linear Address Masking */
diff --git a/arch/x86/include/asm/msr-index.h b/arch/x86/include/asm/msr-index.h
index 7823b87bf383..605c01539b0d 100644
--- a/arch/x86/include/asm/msr-index.h
+++ b/arch/x86/include/asm/msr-index.h
@@ -1111,6 +1111,9 @@
#define MSR_IA32_HW_FEEDBACK_THREAD_CONFIG 0x17d4
#define MSR_IA32_HW_FEEDBACK_CHAR 0x17d2
+/* Hardware History Reset */
+#define MSR_IA32_HW_HRESET_ENABLE 0x17da
+
/* x2APIC locked status */
#define MSR_IA32_XAPIC_DISABLE_STATUS 0xBD
#define LEGACY_XAPIC_DISABLED BIT(0) /*
--
2.25.1