cpuid: Minor improvements

Remove the assembly file that checks if the CPUID instruction is
supported and have it in inline assembly as suggested by Rusty.

Signed-off-by: Ahmed Samy <f.fallen45@gmail.com>

Makefile-ccan

@@ -113,7 +113,6 @@ DIRS=$(patsubst %/, %, $(sort $(foreach m, $(filter-out $(MODS_EXCLUDE), $(MODS_
 ccan/%-Makefile:
 	@echo $@: $(wildcard ccan/$*/*.[ch]) ccan/$*/_info > $@
 	@echo ccan/$*.o: $(patsubst %.c, %.o, $(wildcard ccan/$*/*.c)) >> $@
-	@echo ccan/$*.o: $(patsubst %.S, %.o, $(wildcard ccan/$*/*.S)) >> $@
 
 # We compile all the ccan/foo/*.o files together into ccan/foo.o
 OBJFILES=$(DIRS:=.o)

ccan/cpuid/cpuid.c

@@ -26,11 +26,10 @@
 /* Only compile this file if we're on a x86 machine.  */
 #if defined(__i386__) || defined(__i386) || defined(__x86_64) \
 	|| defined(_M_AMD64) || defined(__M_X64)
-#include <stdint.h>
-#include <string.h>
-
 #include "cpuid.h"
 
+#include <string.h>
+
 enum {
 	CPU_PROC_BRAND_STRING_INTERNAL0  		= 0x80000003,
 	CPU_PROC_BRAND_STRING_INTERNAL1 		= 0x80000004
@@ -65,61 +64,87 @@ static void ___cpuid(cpuid_t info, uint32_t *eax, uint32_t *ebx, uint32_t *ecx,
 static struct {
 	int feature;
 	unsigned mask;
-	int instruction; 	/* 0 = ecx, 1 = edx.  */
+	bool use_edx; 		/* ecx will be used if false.  */
 } features[] = {
-	{ CF_MMX, 		1 << 23, 	1 },
-	{ CF_SSE, 		1 << 25, 	1 },
-	{ CF_SSE2, 		1 << 26, 	1 },
-	{ CF_SSE3, 		1 << 9,  	0 },
-	{ CF_FPU, 		1 << 0,  	1 },
+	{ CF_MMX, 		1 << 23, 	true },
+	{ CF_SSE, 		1 << 25, 	true },
+	{ CF_SSE2, 		1 << 26, 	true },
+	{ CF_SSE3, 		1 << 9,  	false },
+	{ CF_FPU, 		1 << 0,  	true },
 
-	{ CF_TSC, 		1 << 4,  	1 },
-	{ CF_MSR, 		1 << 5,  	1 },
+	{ CF_TSC, 		1 << 4,  	true },
+	{ CF_MSR, 		1 << 5,  	true },
 
-	{ CF_SSSE3,     	1 << 9,  	0 },
-	{ CF_AVX, 		1 << 28, 	0 },
+	{ CF_SSSE3,     	1 << 9,  	false },
+	{ CF_AVX, 		1 << 28, 	false },
 
 	/* Extended ones.  */
-	{ CEF_x64, 		1 << 30, 	1 },
-	{ CEF_FPU, 		1 << 0,  	1 },
-	{ CEF_DE, 		1 << 2,  	1 },
-	{ CEF_SYSCALLRET, 	1 << 11, 	1 },
-	{ CEF_CMOV, 		1 << 15, 	1 },
-
-	{ CEF_SSE4a, 		1 << 6, 	0 },
-	{ CEF_FMA4, 		1 << 16, 	0 },
-	{ CEF_XOP, 		1 << 11, 	0 }
+	{ CEF_x64, 		1 << 30, 	true },
+	{ CEF_FPU, 		1 << 0,  	true },
+	{ CEF_DE, 		1 << 2,  	true },
+	{ CEF_SYSCALLRET, 	1 << 11, 	true },
+	{ CEF_CMOV, 		1 << 15, 	true },
+
+	{ CEF_SSE4a, 		1 << 6, 	false },
+	{ CEF_FMA4, 		1 << 16, 	false },
+	{ CEF_XOP, 		1 << 11, 	false }
 };
 
-static int has_feature(int feature, uint32_t ecx, uint32_t edx)
+static bool has_feature(int feature, uint32_t ecx, uint32_t edx)
 {
 	int i;
 
 	for (i = 0; i < sizeof(features) / sizeof(features[0]); ++i) {
 		if (features[i].feature == feature) {
-			if (features[i].instruction == 0)
-				return (ecx & features[i].mask);
-			else
+			if (features[i].use_edx)
 				return (edx & features[i].mask);
+			else
+				return (ecx & features[i].mask);
 		}
 	}
 
-	return 0;
+	return false;
 }
 
-int cpuid_test_feature(cpuid_t feature)
+bool cpuid_is_supported(void)
+{
+	int ret = 0;
+
+	asm volatile(
+		"pushfl\n\t"
+		"popl %%eax\n\t"
+		"movl %%eax, %%ecx\n\t"
+		"xorl $0x200000, %%eax\n\t"
+		"pushl %%eax\n\t"
+		"popfl\n\t"
+
+		"pushfl\n\t"
+		"popl %%eax\n\t"
+		"xorl %%ecx, %%eax\n\t"
+		"shrl $21, %%eax\n\t"
+		"andl $1, %%eax\n\t"
+		"pushl %%ecx\n\t"
+		"popfl\n\t"
+
+		: "=a" (ret)
+	);
+
+	return !!ret;
+}
+
+bool cpuid_test_feature(cpuid_t feature)
 {
 	if (feature > CPU_VIRT_PHYS_ADDR_SIZES || feature < CPU_EXTENDED_PROC_INFO_FEATURE_BITS)
-		return 0;
+		return false;
 
 	return (feature <= cpuid_highest_ext_func_supported());
 }
 
-int cpuid_has_feature(int feature, int extended)
+bool cpuid_has_feature(int feature, bool extended)
 {
 	uint32_t eax, ebx, ecx, edx;
 
-	if (extended == 0)
+	if (!extended)
 		___cpuid(CPU_PROCINFO_AND_FEATUREBITS, &eax, &ebx, &ecx, &edx);
 	else
 		___cpuid(CPU_EXTENDED_PROC_INFO_FEATURE_BITS, &eax, &ebx, &ecx, &edx);
@@ -175,9 +200,9 @@ const char *cpuid_get_cpu_type_string(const cputype_t cputype)
 	return cpuids[(int)cputype];
 }
 
-int cpuid_highest_ext_func_supported(void)
+uint32_t cpuid_highest_ext_func_supported(void)
 {
-	static int highest;
+	static uint32_t highest;
 
 	if (!highest) {
 		asm volatile(
@@ -190,7 +215,7 @@ int cpuid_highest_ext_func_supported(void)
 	return highest;
 }
 
-void cpuid(cpuid_t info, void *buf)
+void cpuid(cpuid_t info, uint32_t *buf)
 {
 	/* Sanity checks, make sure we're not trying to do something
 	 * invalid or we are trying to get information that isn't supported
@@ -199,14 +224,13 @@ void cpuid(cpuid_t info, void *buf)
 		&& !cpuid_test_feature(info)))
 		return;
 
-	uint32_t *ubuf = buf;
 	if (info == CPU_PROC_BRAND_STRING) {
-		___cpuid(CPU_PROC_BRAND_STRING,  	  &ubuf[0], &ubuf[1], &ubuf[2],  &ubuf[3]);
-		___cpuid(CPU_PROC_BRAND_STRING_INTERNAL0, &ubuf[4], &ubuf[5], &ubuf[6],  &ubuf[7]);
-		___cpuid(CPU_PROC_BRAND_STRING_INTERNAL1, &ubuf[8], &ubuf[9], &ubuf[10], &ubuf[11]);
+		___cpuid(CPU_PROC_BRAND_STRING,  	  &buf[0], &buf[1], &buf[2],  &buf[3]);
+		___cpuid(CPU_PROC_BRAND_STRING_INTERNAL0, &buf[4], &buf[5], &buf[6],  &buf[7]);
+		___cpuid(CPU_PROC_BRAND_STRING_INTERNAL1, &buf[8], &buf[9], &buf[10], &buf[11]);
 		return;
 	} else if (info == CPU_HIGHEST_EXTENDED_FUNCTION_SUPPORTED) {
-		*ubuf = cpuid_highest_ext_func_supported();
+		*buf = cpuid_highest_ext_func_supported();
 		return;
 	}
 
@@ -215,44 +239,42 @@ void cpuid(cpuid_t info, void *buf)
 
 	switch (info) {
 		case CPU_VENDORID:
-			ubuf[0] = ebx;
-			ubuf[1] = edx;
-			ubuf[2] = ecx;
+			buf[0] = ebx;
+			buf[1] = edx;
+			buf[2] = ecx;
 			break;
 		case CPU_PROCINFO_AND_FEATUREBITS:
-			ubuf[0] = eax; 	/* The so called "signature" of the CPU.  */
-			ubuf[1] = edx; 	/* Feature flags #1.  */
-			ubuf[2] = ecx; 	/* Feature flags #2.  */
-			ubuf[3] = ebx; 	/* Additional feature information.  */
+			buf[0] = eax; 	/* The so called "signature" of the CPU.  */
+			buf[1] = edx; 	/* Feature flags #1.  */
+			buf[2] = ecx; 	/* Feature flags #2.  */
+			buf[3] = ebx; 	/* Additional feature information.  */
 			break;
 		case CPU_CACHE_AND_TLBD_INFO:
-			ubuf[0] = eax;
-			ubuf[1] = ebx;
-			ubuf[2] = ecx;
-			ubuf[3] = edx;
+			buf[0] = eax;
+			buf[1] = ebx;
+			buf[2] = ecx;
+			buf[3] = edx;
 			break;
 		case CPU_EXTENDED_PROC_INFO_FEATURE_BITS:
-			ubuf[0] = edx;
-			ubuf[1] = ecx;
+			buf[0] = edx;
+			buf[1] = ecx;
 			break;
 		case CPU_L1_CACHE_AND_TLB_IDS:
 			break;
 		case CPU_EXTENDED_L2_CACHE_FEATURES:
-			*ubuf = ecx;
+			*buf = ecx;
 			break;
 		case CPU_ADV_POWER_MGT_INFO:
-			*ubuf = edx;
+			*buf = edx;
 			break;
 		case CPU_VIRT_PHYS_ADDR_SIZES:
-			*ubuf = eax;
+			*buf = eax;
 			break;
 		default:
-			*ubuf = 0xbaadf00d;
+			*buf = 0xbaadf00d;
 			break;
 	}
 }
 
-#else
-#warning "Cannot compile this file on a non-x86 machine"
 #endif
 

ccan/cpuid/cpuid.h

@@ -22,6 +22,9 @@
 #ifndef CCAN_CPUID_H
 #define CCAN_CPUID_H
 
+#include <stdbool.h>
+#include <stdint.h>
+
 /**
  * enum cpuid - stuff to get information on from the CPU.
  *
@@ -111,6 +114,9 @@ typedef enum cputype {
 	CT_KVM
 } cputype_t;
 
+#if defined(__i386__) || defined(__i386) || defined(__x86_64) \
+	|| defined(_M_AMD64) || defined(__M_X64)
+
 /**
  * cpuid_get_cpu_type - Get CPU Type
  *
@@ -132,11 +138,11 @@ const char *cpuid_get_cpu_type_string(const cputype_t cputype);
  *
  * CPUID is not supported by old CPUS.
  *
- * Returns 1 if the cpuid instruction is supported, 0 otherwise.
+ * Returns true if the cpuid instruction is supported, false otherwise.
  *
  * See also: cpuid()
  */
-int cpuid_is_supported(void);
+bool cpuid_is_supported(void);
 
 /**
  * cpuid_highest_ext_func_supported - Get the highest extended function supported
@@ -152,7 +158,7 @@ int cpuid_is_supported(void);
  *
  * See also: cpuid()
  */
-int cpuid_highest_ext_func_supported(void);
+uint32_t cpuid_highest_ext_func_supported(void);
 
 /**
  * cpuid - Get Some information from the CPU.
@@ -190,43 +196,56 @@ int cpuid_highest_ext_func_supported(void);
  *
  * If an invalid flag has been passed a 0xbaadf00d is returned in *buf.
  */
-void cpuid(cpuid_t info, void *buf);
+void cpuid(cpuid_t info, uint32_t *buf);
 
 /**
  * cpuid_test_feature - Test if @feature is available
  *
- * Returns 1 if feature is supported, 0 otherwise.
+ * Returns true if feature is supported, false otherwise.
  *
  * The feature parameter must be >= CPU_EXTENDED_PROC_INFO_FEATURE_BITS
  *  and <= CPU_VIRT_PHYS_ADDR_SIZES.
  */
-int cpuid_test_feature(cpuid_t feature);
+bool cpuid_test_feature(cpuid_t feature);
 
 /**
  * cpuid_has_feature - Test if @feature is supported
  *
  * Test if the CPU supports MMX/SSE* etc.
  * For the extended parameter, usually you want to pass it as
- * 0 if you're not passing CEF_*.
+ * false if you're not passing CEF_*.
  *
  * For more information about the CPU extended features, have a look
  * at:
  * 	http://en.wikipedia.org/wiki/CPUID
  *
- * Returns 1 if the feature is available, 0 otherwise.
+ * Returns true if the feature is available, false otherwise.
  */
-#define cpuid_has_mmx() 	cpuid_has_feature(CF_MMX, 	0)
-#define cpuid_has_sse() 	cpuid_has_feature(CF_SSE, 	0)
-#define cpuid_has_sse2() 	cpuid_has_feature(CF_SSE2, 	0)
-#define cpuid_has_sse3() 	cpuid_has_feature(CF_SSE3, 	0)
-#define cpuid_has_ssse3() 	cpuid_has_feature(CF_SSSE3, 	0)
-#define cpuid_has_avx() 	cpuid_has_feature(CF_AVX, 	0)
-#define cpuid_has_fma() 	cpuid_has_feature(CF_FMA, 	0)
-#define cpuid_has_x64() 	cpuid_has_feature(CEF_x64, 	1)
-#define cpuid_has_sse4a() 	cpuid_has_feature(CEF_SSE4a, 	1)
-#define cpuid_has_fma4() 	cpuid_has_feature(CEF_FMA4, 	1)
-#define cpuid_has_xop() 	cpuid_has_feature(CEF_XOP, 	1)
-int cpuid_has_feature(int feature, int extended);
+#define cpuid_has_mmx() 	cpuid_has_feature(CF_MMX, 	false)
+#define cpuid_has_sse() 	cpuid_has_feature(CF_SSE, 	false)
+#define cpuid_has_sse2() 	cpuid_has_feature(CF_SSE2, 	false)
+#define cpuid_has_sse3() 	cpuid_has_feature(CF_SSE3, 	false)
+#define cpuid_has_ssse3() 	cpuid_has_feature(CF_SSSE3, 	false)
+#define cpuid_has_avx() 	cpuid_has_feature(CF_AVX, 	false)
+#define cpuid_has_fma() 	cpuid_has_feature(CF_FMA, 	false)
+#define cpuid_has_x64() 	cpuid_has_feature(CEF_x64, 	true)
+#define cpuid_has_sse4a() 	cpuid_has_feature(CEF_SSE4a, 	true)
+#define cpuid_has_fma4() 	cpuid_has_feature(CEF_FMA4, 	true)
+#define cpuid_has_xop() 	cpuid_has_feature(CEF_XOP, 	true)
+bool cpuid_has_feature(int feature, bool extended);
+
+#else
+
+#define cpuid_get_cpu_type() 			BUILD_ASSERT_OR_ZERO(0)
+#define cpuid_get_cpu_type_string() 		BUILD_ASSERT_OR_ZERO(0)
 
+#define cpuid_is_supported() 			BUILD_ASSERT_OR_ZERO(0)
+#define cpuid(info, buf) 			BUILD_ASSERT_OR_ZERO(0)
+
+#define cpuid_highest_ext_func_supported() 	BUILD_ASSERT_OR_ZERO(0)
+#define cpuid_test_feature(feature) 		BUILD_ASSERT_OR_ZERO(0)
+#define cpuid_has_feature(feature, ext) 	BUILD_ASSERT_OR_ZERO(0)
+
+#endif
 #endif
 

ccan/cpuid/issupprted.S

@@ -1,34 +0,0 @@
-/*
-  Test if the CPUID instruction is available.
-  returns 1 if so, 0 otherwise.  */
-
-/* Only compile this file if we're on a x86 machine.  */
-#if defined(__i386__) || defined(__i386) || defined(__x86_64) \
-	|| defined(_M_AMD64) || defined(__M_X64)
-
-.section .text
-.global cpuid_is_supported
-.type cpuid_is_supported, @function
-cpuid_is_supported:
-	nop
-
-	pushfl
-	popl %eax
-	movl %eax, %ecx
-	xorl $0x200000, %eax
-	pushl %eax
-	popfl
-
-	pushfl
-	popl %eax
-	xorl %ecx, %eax
-	shrl $21, %eax
-	andl $1, %eax
-	pushl %ecx
-	popfl
-
-	ret
-
-	.size cpuid_is_supported, .-cpuid_is_supported
-#endif
-

ccan/cpuid/test/run.c

@@ -13,7 +13,7 @@ int main()
 	printf ("Vendor ID: %s\n", cpuid_get_cpu_type_string (cpuid_get_cpu_type ()));
 
 	char buf[48];
-	cpuid(CPU_PROC_BRAND_STRING, buf);
+	cpuid(CPU_PROC_BRAND_STRING, (uint32_t *)buf);
 	printf ("Processor Brand: %s\n", buf);
 
 	printf ("Highest extended function supported: %#010x\n", cpuid_highest_ext_func_supported());
@@ -29,7 +29,7 @@ int main()
 	cpuid(CPU_VIRT_PHYS_ADDR_SIZES, &s.w);
 	printf ("Physical address size: %d\nVirtual: %d\n", s.phys_bits, s.virt_bits);
 
-	int extfeatures[2];
+	uint32_t extfeatures[2];
 	cpuid(CPU_EXTENDED_PROC_INFO_FEATURE_BITS, extfeatures);
 	printf ("Extended processor info and feature bits: %d %d\n", extfeatures[0], extfeatures[1]);
 
@@ -45,11 +45,12 @@ int main()
 	} l2c;
 
 	cpuid(CPU_EXTENDED_L2_CACHE_FEATURES, &l2c.w);
-	printf ("L2 Cache Size: %ld KB\tLine Size: %ld bytes\tAssociativity: %02xh\n",
+	printf ("L2 Cache Size: %u KB\tLine Size: %u bytes\tAssociativity: %02xh\n",
 			l2c.cache_size, l2c.line_size, l2c.assoc);
 
-	int invalid;
+	uint32_t invalid;
 	cpuid(0x0ffffffUL, &invalid);
 	printf ("Testing invalid: %#010x\n", invalid);
 	return 0;
 }
+