x86: generate names for /proc/cpuinfo from <asm/cpufeature.h>

We have had a number of cases where <asm/cpufeature.h> (and its
predecessors) have diverged substantially from the names list in
/proc/cpuinfo.  This patch generates the latter from the former.

It retains the option for explicitly overriding the strings, but by
making that require a separate action it should at least be less
likely to happen.

It would be good to do a future pass and rename strings that are
gratuituously different in the kernel (/proc/cpuinfo is a userspace
interface and must remain constant.)
Signed-off-by: H. Peter Anvin <hpa@zytor.com>

arch/x86/boot/mkcpustr.c

@@ -15,7 +15,7 @@
 
 #include <stdio.h>
 
-#include "../kernel/cpu/feature_names.c"
+#include "../kernel/cpu/capflags.c"
 
 #if NCAPFLAGS > 8
 # error "Need to adjust the boot code handling of CPUID strings"

arch/x86/kernel/cpu/Makefile

@@ -3,7 +3,7 @@
 #
 
 obj-y			:= intel_cacheinfo.o addon_cpuid_features.o
-obj-y			+= proc.o feature_names.o
+obj-y			+= proc.o capflags.o powerflags.o
 
 obj-$(CONFIG_X86_32)	+= common.o bugs.o cmpxchg.o
 obj-$(CONFIG_X86_64)	+= common_64.o bugs_64.o
@@ -23,3 +23,12 @@ obj-$(CONFIG_MTRR)	+= mtrr/
 obj-$(CONFIG_CPU_FREQ)	+= cpufreq/
 
 obj-$(CONFIG_X86_LOCAL_APIC) += perfctr-watchdog.o
+
+quiet_cmd_mkcapflags = MKCAP   $@
+      cmd_mkcapflags = $(PERL) $(srctree)/$(src)/mkcapflags.pl $< $@
+
+cpufeature = $(src)/../../../../include/asm-x86/cpufeature.h
+
+targets += capflags.c
+$(obj)/capflags.c: $(cpufeature) $(src)/mkcapflags.pl FORCE
+	$(call if_changed,mkcapflags)

arch/x86/kernel/cpu/feature_names.c

-/*
- * Strings for the various x86 capability flags.
- *
- * This file must not contain any executable code.
- */
-
-#include <asm/cpufeature.h>
-
-/*
- * These flag bits must match the definitions in <asm/cpufeature.h>.
- * NULL means this bit is undefined or reserved; either way it doesn't
- * have meaning as far as Linux is concerned.  Note that it's important
- * to realize there is a difference between this table and CPUID -- if
- * applications want to get the raw CPUID data, they should access
- * /dev/cpu/<cpu_nr>/cpuid instead.
- */
-const char * const x86_cap_flags[NCAPINTS*32] = {
-	/* Intel-defined */
-	"fpu", "vme", "de", "pse", "tsc", "msr", "pae", "mce",
-	"cx8", "apic", NULL, "sep", "mtrr", "pge", "mca", "cmov",
-	"pat", "pse36", "pn", "clflush", NULL, "dts", "acpi", "mmx",
-	"fxsr", "sse", "sse2", "ss", "ht", "tm", "ia64", "pbe",
-
-	/* AMD-defined */
-	NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
-	NULL, NULL, NULL, "syscall", NULL, NULL, NULL, NULL,
-	NULL, NULL, NULL, "mp", "nx", NULL, "mmxext", NULL,
-	NULL, "fxsr_opt", "pdpe1gb", "rdtscp", NULL, "lm",
-	"3dnowext", "3dnow",
-
-	/* Transmeta-defined */
-	"recovery", "longrun", NULL, "lrti", NULL, NULL, NULL, NULL,
-	NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
-	NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
-	NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
-
-	/* Other (Linux-defined) */
-	"cxmmx", "k6_mtrr", "cyrix_arr", "centaur_mcr",
-	NULL, NULL, NULL, NULL,
-	"constant_tsc", "up", NULL, "arch_perfmon",
-	"pebs", "bts", NULL, NULL,
-	"rep_good", NULL, NULL, NULL,
-	"nopl", NULL, NULL, NULL,
-	NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
-
-	/* Intel-defined (#2) */
-	"pni", NULL, NULL, "monitor", "ds_cpl", "vmx", "smx", "est",
-	"tm2", "ssse3", "cid", NULL, NULL, "cx16", "xtpr", NULL,
-	NULL, NULL, "dca", "sse4_1", "sse4_2", NULL, NULL, "popcnt",
-	NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
-
-	/* VIA/Cyrix/Centaur-defined */
-	NULL, NULL, "rng", "rng_en", NULL, NULL, "ace", "ace_en",
-	"ace2", "ace2_en", "phe", "phe_en", "pmm", "pmm_en", NULL, NULL,
-	NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
-	NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
-
-	/* AMD-defined (#2) */
-	"lahf_lm", "cmp_legacy", "svm", "extapic",
-	"cr8_legacy", "abm", "sse4a", "misalignsse",
-	"3dnowprefetch", "osvw", "ibs", "sse5",
-	"skinit", "wdt", NULL, NULL,
-	NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
-	NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
-
-	/* Auxiliary (Linux-defined) */
-	"ida", NULL, NULL, NULL, NULL, NULL, NULL, NULL,
-	NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
-	NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
-	NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
-};
-
-const char *const x86_power_flags[32] = {
-	"ts",	/* temperature sensor */
-	"fid",  /* frequency id control */
-	"vid",  /* voltage id control */
-	"ttp",  /* thermal trip */
-	"tm",
-	"stc",
-	"100mhzsteps",
-	"hwpstate",
-	"",	/* tsc invariant mapped to constant_tsc */
-		/* nothing */
-};

arch/x86/kernel/cpu/mkcapflags.pl

+#!/usr/bin/perl
+#
+# Generate the x86_cap_flags[] array from include/asm-x86/cpufeature.h
+#
+
+($in, $out) = @ARGV;
+
+open(IN, "< $in\0")   or die "$0: cannot open: $in: $!\n";
+open(OUT, "> $out\0") or die "$0: cannot create: $out: $!\n";
+
+print OUT "#include <asm/cpufeature.h>\n\n";
+print OUT "const char * const x86_cap_flags[NCAPINTS*32] = {\n";
+
+while (defined($line = <IN>)) {
+	if ($line =~ /^\s*\#\s*define\s+(X86_FEATURE_(\S+))\s+(.*)$/) {
+		$macro = $1;
+		$feature = $2;
+		$tail = $3;
+		if ($tail =~ /\/\*\s*\"([^"]*)\".*\*\//) {
+			$feature = $1;
+		}
+
+		if ($feature ne '') {
+			printf OUT "\t%-32s = \"%s\",\n",
+				"[$macro]", "\L$feature";
+		}
+	}
+}
+print OUT "};\n";
+
+close(IN);
+close(OUT);

arch/x86/kernel/cpu/powerflags.c

+/*
+ * Strings for the various x86 power flags
+ *
+ * This file must not contain any executable code.
+ */
+
+#include <asm/cpufeature.h>
+
+const char *const x86_power_flags[32] = {
+	"ts",	/* temperature sensor */
+	"fid",  /* frequency id control */
+	"vid",  /* voltage id control */
+	"ttp",  /* thermal trip */
+	"tm",
+	"stc",
+	"100mhzsteps",
+	"hwpstate",
+	"",	/* tsc invariant mapped to constant_tsc */
+		/* nothing */
+};

include/asm-x86/cpufeature.h

@@ -8,6 +8,12 @@
 
 #define NCAPINTS	8	/* N 32-bit words worth of info */
 
+/*
+ * Note: If the comment begins with a quoted string, that string is used
+ * in /proc/cpuinfo instead of the macro name.  If the string is "",
+ * this feature bit is not displayed in /proc/cpuinfo at all.
+ */
+
 /* Intel-defined CPU features, CPUID level 0x00000001 (edx), word 0 */
 #define X86_FEATURE_FPU		(0*32+ 0) /* Onboard FPU */
 #define X86_FEATURE_VME		(0*32+ 1) /* Virtual Mode Extensions */
@@ -27,18 +33,18 @@
 #define X86_FEATURE_PAT		(0*32+16) /* Page Attribute Table */
 #define X86_FEATURE_PSE36	(0*32+17) /* 36-bit PSEs */
 #define X86_FEATURE_PN		(0*32+18) /* Processor serial number */
-#define X86_FEATURE_CLFLSH	(0*32+19) /* Supports the CLFLUSH instruction */
-#define X86_FEATURE_DS		(0*32+21) /* Debug Store */
+#define X86_FEATURE_CLFLSH	(0*32+19) /* "clflush" Supports the CLFLUSH instruction */
+#define X86_FEATURE_DS		(0*32+21) /* "dts" Debug Store */
 #define X86_FEATURE_ACPI	(0*32+22) /* ACPI via MSR */
 #define X86_FEATURE_MMX		(0*32+23) /* Multimedia Extensions */
-#define X86_FEATURE_FXSR	(0*32+24) /* FXSAVE and FXRSTOR instructions (fast save and restore */
-					  /* of FPU context), and CR4.OSFXSR available */
-#define X86_FEATURE_XMM		(0*32+25) /* Streaming SIMD Extensions */
-#define X86_FEATURE_XMM2	(0*32+26) /* Streaming SIMD Extensions-2 */
-#define X86_FEATURE_SELFSNOOP	(0*32+27) /* CPU self snoop */
+#define X86_FEATURE_FXSR	(0*32+24) /* FXSAVE/FXRSTOR, CR4.OSFXSR */
+#define X86_FEATURE_XMM		(0*32+25) /* "sse" */
+#define X86_FEATURE_XMM2	(0*32+26) /* "sse2" */
+#define X86_FEATURE_SELFSNOOP	(0*32+27) /* "ss" CPU self snoop */
 #define X86_FEATURE_HT		(0*32+28) /* Hyper-Threading */
-#define X86_FEATURE_ACC		(0*32+29) /* Automatic clock control */
+#define X86_FEATURE_ACC		(0*32+29) /* "tm" Automatic clock control */
 #define X86_FEATURE_IA64	(0*32+30) /* IA-64 processor */
+#define X86_FEATURE_PBE		(0*32+31) /* Pending Break Enable */
 
 /* AMD-defined CPU features, CPUID level 0x80000001, word 1 */
 /* Don't duplicate feature flags which are redundant with Intel! */
@@ -46,7 +52,8 @@
 #define X86_FEATURE_MP		(1*32+19) /* MP Capable. */
 #define X86_FEATURE_NX		(1*32+20) /* Execute Disable */
 #define X86_FEATURE_MMXEXT	(1*32+22) /* AMD MMX extensions */
-#define X86_FEATURE_GBPAGES	(1*32+26) /* GB pages */
+#define X86_FEATURE_FXSR_OPT	(1*32+25) /* FXSAVE/FXRSTOR optimizations */
+#define X86_FEATURE_GBPAGES	(1*32+26) /* "pdpe1gb" GB pages */
 #define X86_FEATURE_RDTSCP	(1*32+27) /* RDTSCP */
 #define X86_FEATURE_LM		(1*32+29) /* Long Mode (x86-64) */
 #define X86_FEATURE_3DNOWEXT	(1*32+30) /* AMD 3DNow! extensions */
@@ -64,52 +71,67 @@
 #define X86_FEATURE_CYRIX_ARR	(3*32+ 2) /* Cyrix ARRs (= MTRRs) */
 #define X86_FEATURE_CENTAUR_MCR	(3*32+ 3) /* Centaur MCRs (= MTRRs) */
 /* cpu types for specific tunings: */
-#define X86_FEATURE_K8		(3*32+ 4) /* Opteron, Athlon64 */
-#define X86_FEATURE_K7		(3*32+ 5) /* Athlon */
-#define X86_FEATURE_P3		(3*32+ 6) /* P3 */
-#define X86_FEATURE_P4		(3*32+ 7) /* P4 */
+#define X86_FEATURE_K8		(3*32+ 4) /* "" Opteron, Athlon64 */
+#define X86_FEATURE_K7		(3*32+ 5) /* "" Athlon */
+#define X86_FEATURE_P3		(3*32+ 6) /* "" P3 */
+#define X86_FEATURE_P4		(3*32+ 7) /* "" P4 */
 #define X86_FEATURE_CONSTANT_TSC (3*32+ 8) /* TSC ticks at a constant rate */
 #define X86_FEATURE_UP		(3*32+ 9) /* smp kernel running on up */
-#define X86_FEATURE_FXSAVE_LEAK (3*32+10) /* FXSAVE leaks FOP/FIP/FOP */
+#define X86_FEATURE_FXSAVE_LEAK (3*32+10) /* "" FXSAVE leaks FOP/FIP/FOP */
 #define X86_FEATURE_ARCH_PERFMON (3*32+11) /* Intel Architectural PerfMon */
 #define X86_FEATURE_PEBS	(3*32+12) /* Precise-Event Based Sampling */
 #define X86_FEATURE_BTS		(3*32+13) /* Branch Trace Store */
-#define X86_FEATURE_SYSCALL32	(3*32+14) /* syscall in ia32 userspace */
-#define X86_FEATURE_SYSENTER32	(3*32+15) /* sysenter in ia32 userspace */
+#define X86_FEATURE_SYSCALL32	(3*32+14) /* "" syscall in ia32 userspace */
+#define X86_FEATURE_SYSENTER32	(3*32+15) /* "" sysenter in ia32 userspace */
 #define X86_FEATURE_REP_GOOD	(3*32+16) /* rep microcode works well on this CPU */
-#define X86_FEATURE_MFENCE_RDTSC (3*32+17) /* Mfence synchronizes RDTSC */
-#define X86_FEATURE_LFENCE_RDTSC (3*32+18) /* Lfence synchronizes RDTSC */
-#define X86_FEATURE_11AP	(3*32+19) /* Bad local APIC aka 11AP */
+#define X86_FEATURE_MFENCE_RDTSC (3*32+17) /* "" Mfence synchronizes RDTSC */
+#define X86_FEATURE_LFENCE_RDTSC (3*32+18) /* "" Lfence synchronizes RDTSC */
+#define X86_FEATURE_11AP	(3*32+19) /* "" Bad local APIC aka 11AP */
 #define X86_FEATURE_NOPL	(3*32+20) /* The NOPL (0F 1F) instructions */
 
 /* Intel-defined CPU features, CPUID level 0x00000001 (ecx), word 4 */
-#define X86_FEATURE_XMM3	(4*32+ 0) /* Streaming SIMD Extensions-3 */
-#define X86_FEATURE_MWAIT	(4*32+ 3) /* Monitor/Mwait support */
-#define X86_FEATURE_DSCPL	(4*32+ 4) /* CPL Qualified Debug Store */
+#define X86_FEATURE_XMM3	(4*32+ 0) /* "pni" SSE-3 */
+#define X86_FEATURE_MWAIT	(4*32+ 3) /* "monitor" Monitor/Mwait support */
+#define X86_FEATURE_DSCPL	(4*32+ 4) /* "ds_cpl" CPL Qual. Debug Store */
+#define X86_FEATURE_VMX		(4*32+ 5) /* Hardware virtualization */
+#define X86_FEATURE_SMX		(4*32+ 6) /* "Safer" mode */
 #define X86_FEATURE_EST		(4*32+ 7) /* Enhanced SpeedStep */
 #define X86_FEATURE_TM2		(4*32+ 8) /* Thermal Monitor 2 */
+#define X86_FEATURE_SSSE3	(4*32+ 9) /* Supplemental SSE-3 */
 #define X86_FEATURE_CID		(4*32+10) /* Context ID */
 #define X86_FEATURE_CX16	(4*32+13) /* CMPXCHG16B */
 #define X86_FEATURE_XTPR	(4*32+14) /* Send Task Priority Messages */
 #define X86_FEATURE_DCA		(4*32+18) /* Direct Cache Access */
-#define X86_FEATURE_XMM4_2	(4*32+20) /* Streaming SIMD Extensions-4.2 */
+#define X86_FEATURE_XMM4_1	(4*32+19) /* "sse4_1" SSE-4.1 */
+#define X86_FEATURE_XMM4_2	(4*32+20) /* "sse4_2" SSE-4.2 */
 
 /* VIA/Cyrix/Centaur-defined CPU features, CPUID level 0xC0000001, word 5 */
-#define X86_FEATURE_XSTORE	(5*32+ 2) /* on-CPU RNG present (xstore insn) */
-#define X86_FEATURE_XSTORE_EN	(5*32+ 3) /* on-CPU RNG enabled */
-#define X86_FEATURE_XCRYPT	(5*32+ 6) /* on-CPU crypto (xcrypt insn) */
-#define X86_FEATURE_XCRYPT_EN	(5*32+ 7) /* on-CPU crypto enabled */
+#define X86_FEATURE_XSTORE	(5*32+ 2) /* "rng" RNG present (xstore) */
+#define X86_FEATURE_XSTORE_EN	(5*32+ 3) /* "rng_en" RNG enabled */
+#define X86_FEATURE_XCRYPT	(5*32+ 6) /* "ace" on-CPU crypto (xcrypt) */
+#define X86_FEATURE_XCRYPT_EN	(5*32+ 7) /* "ace_en" on-CPU crypto enabled */
 #define X86_FEATURE_ACE2	(5*32+ 8) /* Advanced Cryptography Engine v2 */
 #define X86_FEATURE_ACE2_EN	(5*32+ 9) /* ACE v2 enabled */
-#define X86_FEATURE_PHE		(5*32+ 10) /* PadLock Hash Engine */
-#define X86_FEATURE_PHE_EN	(5*32+ 11) /* PHE enabled */
-#define X86_FEATURE_PMM		(5*32+ 12) /* PadLock Montgomery Multiplier */
-#define X86_FEATURE_PMM_EN	(5*32+ 13) /* PMM enabled */
+#define X86_FEATURE_PHE		(5*32+10) /* PadLock Hash Engine */
+#define X86_FEATURE_PHE_EN	(5*32+11) /* PHE enabled */
+#define X86_FEATURE_PMM		(5*32+12) /* PadLock Montgomery Multiplier */
+#define X86_FEATURE_PMM_EN	(5*32+13) /* PMM enabled */
 
 /* More extended AMD flags: CPUID level 0x80000001, ecx, word 6 */
 #define X86_FEATURE_LAHF_LM	(6*32+ 0) /* LAHF/SAHF in long mode */
 #define X86_FEATURE_CMP_LEGACY	(6*32+ 1) /* If yes HyperThreading not valid */
-#define X86_FEATURE_IBS		(6*32+ 10) /* Instruction Based Sampling */
+#define X86_FEATURE_SVM		(6*32+ 2) /* Secure virtual machine */
+#define X86_FEATURE_EXTAPIC	(6*32+ 3) /* Extended APIC space */
+#define X86_FEATURE_CR8_LEGACY	(6*32+ 4) /* CR8 in 32-bit mode */
+#define X86_FEATURE_ABM		(6*32+ 5) /* Advanced bit manipulation */
+#define X86_FEATURE_SSE4A	(6*32+ 6) /* SSE-4A */
+#define X86_FEATURE_MISALIGNSSE (6*32+ 7) /* Misaligned SSE mode */
+#define X86_FEATURE_3DNOWPREFETCH (6*32+ 8) /* 3DNow prefetch instructions */
+#define X86_FEATURE_OSVW	(6*32+ 9) /* OS Visible Workaround */
+#define X86_FEATURE_IBS		(6*32+10) /* Instruction Based Sampling */
+#define X86_FEATURE_SSE5	(6*32+11) /* SSE-5 */
+#define X86_FEATURE_SKINIT	(6*32+12) /* SKINIT/STGI instructions */
+#define X86_FEATURE_WDT		(6*32+13) /* Watchdog timer */
 
 /*
  * Auxiliary flags: Linux defined - For features scattered in various