[PATCH] x86: more asm cleanups

Some more assembler cleanups I noticed along the way. Signed-off-by: Zachary Amsden <zach@vmware.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[PATCH] x86: more asm cleanups
Some more assembler cleanups I noticed along the way. Signed-off-by: Zachary Amsden <zach@vmware.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Zachary Amsden · Linus Torvalds
1 parent 4f0cb8d978
Showing 8 changed files with 35 additions and 50 deletions Side-by-side Diff
arch/i386/kernel/cpu/intel.c
arch/i386/kernel/crash.c
arch/i386/kernel/machine_kexec.c
arch/i386/kernel/msr.c
arch/i386/kernel/process.c
arch/i386/mach-voyager/voyager_basic.c
arch/i386/mach-voyager/voyager_smp.c
include/asm-i386/msr.h
@@ -82,16 +82,13 @@
  */
 static int __devinit num_cpu_cores(struct cpuinfo_x86 *c)
 {
-	unsigned int eax;
+	unsigned int eax, ebx, ecx, edx;
  
 	if (c->cpuid_level < 4)
 		return 1;
  
-	__asm__("cpuid"
-		: "=a" (eax)
-		: "0" (4), "c" (0)
-		: "bx", "dx");
-
+	/* Intel has a non-standard dependency on %ecx for this CPUID level. */
+	cpuid_count(4, 0, &eax, &ebx, &ecx, &edx);
 	if (eax & 0x1f)
 		return ((eax >> 26) + 1);
 	else
@@ -153,7 +153,7 @@
 	disable_local_APIC();
 	atomic_dec(&waiting_for_crash_ipi);
 	/* Assume hlt works */
-	__asm__("hlt");
+	halt();
 	for(;;);
  
 	return 1;
@@ -93,10 +93,7 @@
 	curidt.size    = limit;
 	curidt.address = (unsigned long)newidt;
  
-	__asm__ __volatile__ (
-		"lidtl %0\n"
-		: : "m" (curidt)
-		);
+	load_idt(&curidt);
 };
  
  
@@ -108,10 +105,7 @@
 	curgdt.size    = limit;
 	curgdt.address = (unsigned long)newgdt;
  
-	__asm__ __volatile__ (
-		"lgdtl %0\n"
-		: : "m" (curgdt)
-		);
+	load_gdt(&curgdt);
 };
  
 static void load_segments(void)
@@ -46,23 +46,13 @@
  
 static struct class *msr_class;
  
-/* Note: "err" is handled in a funny way below.  Otherwise one version
-   of gcc or another breaks. */
-
 static inline int wrmsr_eio(u32 reg, u32 eax, u32 edx)
 {
 	int err;
  
-	asm volatile ("1:	wrmsr\n"
-		      "2:\n"
-		      ".section .fixup,\"ax\"\n"
-		      "3:	movl %4,%0\n"
-		      "	jmp 2b\n"
-		      ".previous\n"
-		      ".section __ex_table,\"a\"\n"
-		      "	.align 4\n" "	.long 1b,3b\n" ".previous":"=&bDS" (err)
-		      :"a"(eax), "d"(edx), "c"(reg), "i"(-EIO), "0"(0));
-
+	err = wrmsr_safe(reg, eax, edx);
+	if (err)
+		err = -EIO;
 	return err;
 }
  
@@ -70,18 +60,9 @@
 {
 	int err;
  
-	asm volatile ("1:	rdmsr\n"
-		      "2:\n"
-		      ".section .fixup,\"ax\"\n"
-		      "3:	movl %4,%0\n"
-		      "	jmp 2b\n"
-		      ".previous\n"
-		      ".section __ex_table,\"a\"\n"
-		      "	.align 4\n"
-		      "	.long 1b,3b\n"
-		      ".previous":"=&bDS" (err), "=a"(*eax), "=d"(*edx)
-		      :"c"(reg), "i"(-EIO), "0"(0));
-
+	err = rdmsr_safe(reg, eax, edx);
+	if (err)
+		err = -EIO;
 	return err;
 }
  
@@ -164,7 +164,7 @@
 	 */
 	local_irq_disable();
 	while (1)
-		__asm__ __volatile__("hlt":::"memory");
+		halt();
 }
 #else
 static inline void play_dead(void)
@@ -234,10 +234,9 @@
 #endif
 	}
 	/* and wait for it to happen */
-	for(;;) {
-		__asm("cli");
-		__asm("hlt");
-	}
+	local_irq_disable();
+	for(;;)
+		halt();
 }
  
 /* copied from process.c */
@@ -278,10 +277,9 @@
 		outb(basebd | 0x08, VOYAGER_MC_SETUP);
 		outb(0x02, catbase + 0x21);
 	}
-	for(;;) {
-		asm("cli");
-		asm("hlt");
-	}
+	local_irq_disable();
+	for(;;)
+		halt();
 }
  
 void
@@ -1015,7 +1015,7 @@
 	cpu_clear(smp_processor_id(), cpu_online_map);
 	local_irq_disable();
 	for(;;)
-	       __asm__("hlt");
+		halt();
 }
  
 static DEFINE_SPINLOCK(call_lock);
@@ -47,6 +47,21 @@
 		     : "c" (msr), "0" (a), "d" (b), "i" (-EFAULT));\
 	ret__; })
  
+/* rdmsr with exception handling */
+#define rdmsr_safe(msr,a,b) ({ int ret__;						\
+	asm volatile("2: rdmsr ; xorl %0,%0\n"						\
+		     "1:\n\t"								\
+		     ".section .fixup,\"ax\"\n\t"					\
+		     "3:  movl %4,%0 ; jmp 1b\n\t"					\
+		     ".previous\n\t"							\
+ 		     ".section __ex_table,\"a\"\n"					\
+		     "   .align 4\n\t"							\
+		     "   .long 	2b,3b\n\t"						\
+		     ".previous"							\
+		     : "=r" (ret__), "=a" (*(a)), "=d" (*(b))				\
+		     : "c" (msr), "i" (-EFAULT));\
+	ret__; })
+
 #define rdtsc(low,high) \
      __asm__ __volatile__("rdtsc" : "=a" (low), "=d" (high))
...	...	@@ -82,16 +82,13 @@
82	82	*/
83	83	static int __devinit num_cpu_cores(struct cpuinfo_x86 *c)
84	84	{
85		- unsigned int eax;
	85	+ unsigned int eax, ebx, ecx, edx;
86	86
87	87	if (c->cpuid_level < 4)
88	88	return 1;
89	89
90		- __asm__("cpuid"
91		- : "=a" (eax)
92		- : "0" (4), "c" (0)
93		- : "bx", "dx");
94		-
	90	+ /* Intel has a non-standard dependency on %ecx for this CPUID level. */
	91	+ cpuid_count(4, 0, &eax, &ebx, &ecx, &edx);
95	92	if (eax & 0x1f)
96	93	return ((eax >> 26) + 1);
97	94	else
...	...	@@ -153,7 +153,7 @@
153	153	disable_local_APIC();
154	154	atomic_dec(&waiting_for_crash_ipi);
155	155	/* Assume hlt works */
156		- __asm__("hlt");
	156	+ halt();
157	157	for(;;);
158	158
159	159	return 1;
...	...	@@ -93,10 +93,7 @@
93	93	curidt.size = limit;
94	94	curidt.address = (unsigned long)newidt;
95	95
96		- __asm__ __volatile__ (
97		- "lidtl %0\n"
98		- : : "m" (curidt)
99		- );
	96	+ load_idt(&curidt);
100	97	};
101	98
102	99
...	...	@@ -108,10 +105,7 @@
108	105	curgdt.size = limit;
109	106	curgdt.address = (unsigned long)newgdt;
110	107
111		- __asm__ __volatile__ (
112		- "lgdtl %0\n"
113		- : : "m" (curgdt)
114		- );
	108	+ load_gdt(&curgdt);
115	109	};
116	110
117	111	static void load_segments(void)
...	...	@@ -46,23 +46,13 @@
46	46
47	47	static struct class *msr_class;
48	48
49		-/* Note: "err" is handled in a funny way below. Otherwise one version
50		- of gcc or another breaks. */
51		-
52	49	static inline int wrmsr_eio(u32 reg, u32 eax, u32 edx)
53	50	{
54	51	int err;
55	52
56		- asm volatile ("1: wrmsr\n"
57		- "2:\n"
58		- ".section .fixup,\"ax\"\n"
59		- "3: movl %4,%0\n"
60		- " jmp 2b\n"
61		- ".previous\n"
62		- ".section __ex_table,\"a\"\n"
63		- " .align 4\n" " .long 1b,3b\n" ".previous":"=&bDS" (err)
64		- :"a"(eax), "d"(edx), "c"(reg), "i"(-EIO), "0"(0));
65		-
	53	+ err = wrmsr_safe(reg, eax, edx);
	54	+ if (err)
	55	+ err = -EIO;
66	56	return err;
67	57	}
68	58
...	...	@@ -70,18 +60,9 @@
70	60	{
71	61	int err;
72	62
73		- asm volatile ("1: rdmsr\n"
74		- "2:\n"
75		- ".section .fixup,\"ax\"\n"
76		- "3: movl %4,%0\n"
77		- " jmp 2b\n"
78		- ".previous\n"
79		- ".section __ex_table,\"a\"\n"
80		- " .align 4\n"
81		- " .long 1b,3b\n"
82		- ".previous":"=&bDS" (err), "=a"(eax), "=d"(edx)
83		- :"c"(reg), "i"(-EIO), "0"(0));
84		-
	63	+ err = rdmsr_safe(reg, eax, edx);
	64	+ if (err)
	65	+ err = -EIO;
85	66	return err;
86	67	}
87	68
...	...	@@ -164,7 +164,7 @@
164	164	*/
165	165	local_irq_disable();
166	166	while (1)
167		- __asm__ __volatile__("hlt":::"memory");
	167	+ halt();
168	168	}
169	169	#else
170	170	static inline void play_dead(void)
...	...	@@ -234,10 +234,9 @@
234	234	#endif
235	235	}
236	236	/* and wait for it to happen */
237		- for(;;) {
238		- __asm("cli");
239		- __asm("hlt");
240		- }
	237	+ local_irq_disable();
	238	+ for(;;)
	239	+ halt();
241	240	}
242	241
243	242	/* copied from process.c */
...	...	@@ -278,10 +277,9 @@
278	277	outb(basebd \| 0x08, VOYAGER_MC_SETUP);
279	278	outb(0x02, catbase + 0x21);
280	279	}
281		- for(;;) {
282		- asm("cli");
283		- asm("hlt");
284		- }
	280	+ local_irq_disable();
	281	+ for(;;)
	282	+ halt();
285	283	}
286	284
287	285	void
...	...	@@ -1015,7 +1015,7 @@
1015	1015	cpu_clear(smp_processor_id(), cpu_online_map);
1016	1016	local_irq_disable();
1017	1017	for(;;)
1018		- __asm__("hlt");
	1018	+ halt();
1019	1019	}
1020	1020
1021	1021	static DEFINE_SPINLOCK(call_lock);
...	...	@@ -47,6 +47,21 @@
47	47	: "c" (msr), "0" (a), "d" (b), "i" (-EFAULT));\
48	48	ret__; })
49	49
	50	+/* rdmsr with exception handling */
	51	+#define rdmsr_safe(msr,a,b) ({ int ret__; \
	52	+ asm volatile("2: rdmsr ; xorl %0,%0\n" \
	53	+ "1:\n\t" \
	54	+ ".section .fixup,\"ax\"\n\t" \
	55	+ "3: movl %4,%0 ; jmp 1b\n\t" \
	56	+ ".previous\n\t" \
	57	+ ".section __ex_table,\"a\"\n" \
	58	+ " .align 4\n\t" \
	59	+ " .long 2b,3b\n\t" \
	60	+ ".previous" \
	61	+ : "=r" (ret__), "=a" ((a)), "=d" ((b)) \
	62	+ : "c" (msr), "i" (-EFAULT));\
	63	+ ret__; })
	64	+
50	65	#define rdtsc(low,high) \
51	66	__asm__ __volatile__("rdtsc" : "=a" (low), "=d" (high))
52	67