x86/cpufeatures: Combine word 11 and 12 into a new scattered features word
authorFenghua Yu <fenghua.yu@intel.com>
Wed, 19 Jun 2019 16:51:09 +0000 (18:51 +0200)
committerBorislav Petkov <bp@suse.de>
Thu, 20 Jun 2019 10:38:44 +0000 (12:38 +0200)
It's a waste for the four X86_FEATURE_CQM_* feature bits to occupy two
whole feature bits words. To better utilize feature words, re-define
word 11 to host scattered features and move the four X86_FEATURE_CQM_*
features into Linux defined word 11. More scattered features can be
added in word 11 in the future.

Rename leaf 11 in cpuid_leafs to CPUID_LNX_4 to reflect it's a
Linux-defined leaf.

Rename leaf 12 as CPUID_DUMMY which will be replaced by a meaningful
name in the next patch when CPUID.7.1:EAX occupies world 12.

Maximum number of RMID and cache occupancy scale are retrieved from
CPUID.0xf.1 after scattered CQM features are enumerated. Carve out the
code into a separate function.

KVM doesn't support resctrl now. So it's safe to move the
X86_FEATURE_CQM_* features to scattered features word 11 for KVM.

Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Aaron Lewis <aaronlewis@google.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Babu Moger <babu.moger@amd.com>
Cc: "Chang S. Bae" <chang.seok.bae@intel.com>
Cc: "Sean J Christopherson" <sean.j.christopherson@intel.com>
Cc: Frederic Weisbecker <frederic@kernel.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jann Horn <jannh@google.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: kvm ML <kvm@vger.kernel.org>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Nadav Amit <namit@vmware.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Pavel Tatashin <pasha.tatashin@oracle.com>
Cc: Peter Feiner <pfeiner@google.com>
Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Cc: Ravi V Shankar <ravi.v.shankar@intel.com>
Cc: Sherry Hurwitz <sherry.hurwitz@amd.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Thomas Lendacky <Thomas.Lendacky@amd.com>
Cc: x86 <x86@kernel.org>
Link: https://lkml.kernel.org/r/1560794416-217638-2-git-send-email-fenghua.yu@intel.com
arch/x86/include/asm/cpufeature.h
arch/x86/include/asm/cpufeatures.h
arch/x86/kernel/cpu/common.c
arch/x86/kernel/cpu/cpuid-deps.c
arch/x86/kernel/cpu/scattered.c
arch/x86/kvm/cpuid.h

index 1d337c5..403f70c 100644 (file)
@@ -22,8 +22,8 @@ enum cpuid_leafs
        CPUID_LNX_3,
        CPUID_7_0_EBX,
        CPUID_D_1_EAX,
-       CPUID_F_0_EDX,
-       CPUID_F_1_EDX,
+       CPUID_LNX_4,
+       CPUID_DUMMY,
        CPUID_8000_0008_EBX,
        CPUID_6_EAX,
        CPUID_8000_000A_EDX,
index 1017b9c..be858b8 100644 (file)
 #define X86_FEATURE_XGETBV1            (10*32+ 2) /* XGETBV with ECX = 1 instruction */
 #define X86_FEATURE_XSAVES             (10*32+ 3) /* XSAVES/XRSTORS instructions */
 
-/* Intel-defined CPU QoS Sub-leaf, CPUID level 0x0000000F:0 (EDX), word 11 */
-#define X86_FEATURE_CQM_LLC            (11*32+ 1) /* LLC QoS if 1 */
-
-/* Intel-defined CPU QoS Sub-leaf, CPUID level 0x0000000F:1 (EDX), word 12 */
-#define X86_FEATURE_CQM_OCCUP_LLC      (12*32+ 0) /* LLC occupancy monitoring */
-#define X86_FEATURE_CQM_MBM_TOTAL      (12*32+ 1) /* LLC Total MBM monitoring */
-#define X86_FEATURE_CQM_MBM_LOCAL      (12*32+ 2) /* LLC Local MBM monitoring */
+/*
+ * Extended auxiliary flags: Linux defined - for features scattered in various
+ * CPUID levels like 0xf, etc.
+ *
+ * Reuse free bits when adding new feature flags!
+ */
+#define X86_FEATURE_CQM_LLC            (11*32+ 0) /* LLC QoS if 1 */
+#define X86_FEATURE_CQM_OCCUP_LLC      (11*32+ 1) /* LLC occupancy monitoring */
+#define X86_FEATURE_CQM_MBM_TOTAL      (11*32+ 2) /* LLC Total MBM monitoring */
+#define X86_FEATURE_CQM_MBM_LOCAL      (11*32+ 3) /* LLC Local MBM monitoring */
 
 /* AMD-defined CPU features, CPUID level 0x80000008 (EBX), word 13 */
 #define X86_FEATURE_CLZERO             (13*32+ 0) /* CLZERO instruction */
index fe6ed96..efb1142 100644 (file)
@@ -803,33 +803,25 @@ static void init_speculation_control(struct cpuinfo_x86 *c)
 
 static void init_cqm(struct cpuinfo_x86 *c)
 {
-       u32 eax, ebx, ecx, edx;
-
-       /* Additional Intel-defined flags: level 0x0000000F */
-       if (c->cpuid_level >= 0x0000000F) {
+       if (!cpu_has(c, X86_FEATURE_CQM_LLC)) {
+               c->x86_cache_max_rmid  = -1;
+               c->x86_cache_occ_scale = -1;
+               return;
+       }
 
-               /* QoS sub-leaf, EAX=0Fh, ECX=0 */
-               cpuid_count(0x0000000F, 0, &eax, &ebx, &ecx, &edx);
-               c->x86_capability[CPUID_F_0_EDX] = edx;
+       /* will be overridden if occupancy monitoring exists */
+       c->x86_cache_max_rmid = cpuid_ebx(0xf);
 
-               if (cpu_has(c, X86_FEATURE_CQM_LLC)) {
-                       /* will be overridden if occupancy monitoring exists */
-                       c->x86_cache_max_rmid = ebx;
+       if (cpu_has(c, X86_FEATURE_CQM_OCCUP_LLC) ||
+           cpu_has(c, X86_FEATURE_CQM_MBM_TOTAL) ||
+           cpu_has(c, X86_FEATURE_CQM_MBM_LOCAL)) {
+               u32 eax, ebx, ecx, edx;
 
-                       /* QoS sub-leaf, EAX=0Fh, ECX=1 */
-                       cpuid_count(0x0000000F, 1, &eax, &ebx, &ecx, &edx);
-                       c->x86_capability[CPUID_F_1_EDX] = edx;
+               /* QoS sub-leaf, EAX=0Fh, ECX=1 */
+               cpuid_count(0xf, 1, &eax, &ebx, &ecx, &edx);
 
-                       if ((cpu_has(c, X86_FEATURE_CQM_OCCUP_LLC)) ||
-                             ((cpu_has(c, X86_FEATURE_CQM_MBM_TOTAL)) ||
-                              (cpu_has(c, X86_FEATURE_CQM_MBM_LOCAL)))) {
-                               c->x86_cache_max_rmid = ecx;
-                               c->x86_cache_occ_scale = ebx;
-                       }
-               } else {
-                       c->x86_cache_max_rmid = -1;
-                       c->x86_cache_occ_scale = -1;
-               }
+               c->x86_cache_max_rmid  = ecx;
+               c->x86_cache_occ_scale = ebx;
        }
 }
 
index 2c0bd38..fa07a22 100644 (file)
@@ -59,6 +59,9 @@ static const struct cpuid_dep cpuid_deps[] = {
        { X86_FEATURE_AVX512_4VNNIW,    X86_FEATURE_AVX512F   },
        { X86_FEATURE_AVX512_4FMAPS,    X86_FEATURE_AVX512F   },
        { X86_FEATURE_AVX512_VPOPCNTDQ, X86_FEATURE_AVX512F   },
+       { X86_FEATURE_CQM_OCCUP_LLC,    X86_FEATURE_CQM_LLC   },
+       { X86_FEATURE_CQM_MBM_TOTAL,    X86_FEATURE_CQM_LLC   },
+       { X86_FEATURE_CQM_MBM_LOCAL,    X86_FEATURE_CQM_LLC   },
        {}
 };
 
index 94aa1c7..adf9b71 100644 (file)
@@ -26,6 +26,10 @@ struct cpuid_bit {
 static const struct cpuid_bit cpuid_bits[] = {
        { X86_FEATURE_APERFMPERF,       CPUID_ECX,  0, 0x00000006, 0 },
        { X86_FEATURE_EPB,              CPUID_ECX,  3, 0x00000006, 0 },
+       { X86_FEATURE_CQM_LLC,          CPUID_EDX,  1, 0x0000000f, 0 },
+       { X86_FEATURE_CQM_OCCUP_LLC,    CPUID_EDX,  0, 0x0000000f, 1 },
+       { X86_FEATURE_CQM_MBM_TOTAL,    CPUID_EDX,  1, 0x0000000f, 1 },
+       { X86_FEATURE_CQM_MBM_LOCAL,    CPUID_EDX,  2, 0x0000000f, 1 },
        { X86_FEATURE_CAT_L3,           CPUID_EBX,  1, 0x00000010, 0 },
        { X86_FEATURE_CAT_L2,           CPUID_EBX,  2, 0x00000010, 0 },
        { X86_FEATURE_CDP_L3,           CPUID_ECX,  2, 0x00000010, 1 },
index 9a327d5..d78a614 100644 (file)
@@ -47,8 +47,6 @@ static const struct cpuid_reg reverse_cpuid[] = {
        [CPUID_8000_0001_ECX] = {0x80000001, 0, CPUID_ECX},
        [CPUID_7_0_EBX]       = {         7, 0, CPUID_EBX},
        [CPUID_D_1_EAX]       = {       0xd, 1, CPUID_EAX},
-       [CPUID_F_0_EDX]       = {       0xf, 0, CPUID_EDX},
-       [CPUID_F_1_EDX]       = {       0xf, 1, CPUID_EDX},
        [CPUID_8000_0008_EBX] = {0x80000008, 0, CPUID_EBX},
        [CPUID_6_EAX]         = {         6, 0, CPUID_EAX},
        [CPUID_8000_000A_EDX] = {0x8000000a, 0, CPUID_EDX},