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				https://kernel.googlesource.com/pub/scm/linux/kernel/git/torvalds/linux
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	Add per-arch sched_cacheflush() which is a write-back cacheflush used by the migration-cost calibration code at bootup time. Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Nick Piggin <nickpiggin@yahoo.com.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
		
			
				
	
	
		
			378 lines
		
	
	
		
			11 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			378 lines
		
	
	
		
			11 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| #ifndef __ASM_SYSTEM_H
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| #define __ASM_SYSTEM_H
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| 
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| #include <linux/config.h>
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| #include <linux/kernel.h>
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| #include <asm/segment.h>
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| 
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| #ifdef __KERNEL__
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| 
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| #ifdef CONFIG_SMP
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| #define LOCK_PREFIX "lock ; "
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| #else
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| #define LOCK_PREFIX ""
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| #endif
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| 
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| #define __STR(x) #x
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| #define STR(x) __STR(x)
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| 
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| #define __SAVE(reg,offset) "movq %%" #reg ",(14-" #offset ")*8(%%rsp)\n\t"
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| #define __RESTORE(reg,offset) "movq (14-" #offset ")*8(%%rsp),%%" #reg "\n\t"
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| 
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| /* frame pointer must be last for get_wchan */
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| #define SAVE_CONTEXT    "pushq %%rbp ; movq %%rsi,%%rbp\n\t"
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| #define RESTORE_CONTEXT "movq %%rbp,%%rsi ; popq %%rbp\n\t"
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| 
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| #define __EXTRA_CLOBBER  \
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| 	,"rcx","rbx","rdx","r8","r9","r10","r11","r12","r13","r14","r15"
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| 
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| #define switch_to(prev,next,last) \
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| 	asm volatile(SAVE_CONTEXT						    \
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| 		     "movq %%rsp,%P[threadrsp](%[prev])\n\t" /* save RSP */	  \
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| 		     "movq %P[threadrsp](%[next]),%%rsp\n\t" /* restore RSP */	  \
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| 		     "call __switch_to\n\t"					  \
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| 		     ".globl thread_return\n"					\
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| 		     "thread_return:\n\t"					    \
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| 		     "movq %%gs:%P[pda_pcurrent],%%rsi\n\t"			  \
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| 		     "movq %P[thread_info](%%rsi),%%r8\n\t"			  \
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| 		     LOCK "btr  %[tif_fork],%P[ti_flags](%%r8)\n\t"		  \
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| 		     "movq %%rax,%%rdi\n\t" 					  \
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| 		     "jc   ret_from_fork\n\t"					  \
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| 		     RESTORE_CONTEXT						    \
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| 		     : "=a" (last)					  	  \
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| 		     : [next] "S" (next), [prev] "D" (prev),			  \
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| 		       [threadrsp] "i" (offsetof(struct task_struct, thread.rsp)), \
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| 		       [ti_flags] "i" (offsetof(struct thread_info, flags)),\
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| 		       [tif_fork] "i" (TIF_FORK),			  \
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| 		       [thread_info] "i" (offsetof(struct task_struct, thread_info)), \
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| 		       [pda_pcurrent] "i" (offsetof(struct x8664_pda, pcurrent))   \
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| 		     : "memory", "cc" __EXTRA_CLOBBER)
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|     
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| extern void load_gs_index(unsigned); 
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| 
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| /*
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|  * Load a segment. Fall back on loading the zero
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|  * segment if something goes wrong..
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|  */
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| #define loadsegment(seg,value)	\
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| 	asm volatile("\n"			\
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| 		"1:\t"				\
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| 		"movl %k0,%%" #seg "\n"		\
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| 		"2:\n"				\
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| 		".section .fixup,\"ax\"\n"	\
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| 		"3:\t"				\
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| 		"movl %1,%%" #seg "\n\t" 	\
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| 		"jmp 2b\n"			\
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| 		".previous\n"			\
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| 		".section __ex_table,\"a\"\n\t"	\
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| 		".align 8\n\t"			\
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| 		".quad 1b,3b\n"			\
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| 		".previous"			\
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| 		: :"r" (value), "r" (0))
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| 
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| #define set_debug(value,register) \
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|                 __asm__("movq %0,%%db" #register  \
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| 		: /* no output */ \
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| 		:"r" ((unsigned long) value))
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| 
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| 
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| #ifdef __KERNEL__
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| struct alt_instr { 
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| 	__u8 *instr; 		/* original instruction */
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| 	__u8 *replacement;
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| 	__u8  cpuid;		/* cpuid bit set for replacement */
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| 	__u8  instrlen;		/* length of original instruction */
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| 	__u8  replacementlen; 	/* length of new instruction, <= instrlen */ 
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| 	__u8  pad[5];
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| }; 
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| #endif
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| 
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| /*
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|  * Alternative instructions for different CPU types or capabilities.
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|  * 
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|  * This allows to use optimized instructions even on generic binary
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|  * kernels.
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|  * 
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|  * length of oldinstr must be longer or equal the length of newinstr
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|  * It can be padded with nops as needed.
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|  * 
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|  * For non barrier like inlines please define new variants
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|  * without volatile and memory clobber.
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|  */
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| #define alternative(oldinstr, newinstr, feature) 	\
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| 	asm volatile ("661:\n\t" oldinstr "\n662:\n" 		     \
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| 		      ".section .altinstructions,\"a\"\n"     	     \
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| 		      "  .align 8\n"				       \
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| 		      "  .quad 661b\n"            /* label */          \
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| 		      "  .quad 663f\n"		  /* new instruction */ \
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| 		      "  .byte %c0\n"             /* feature bit */    \
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| 		      "  .byte 662b-661b\n"       /* sourcelen */      \
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| 		      "  .byte 664f-663f\n"       /* replacementlen */ \
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| 		      ".previous\n"					\
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| 		      ".section .altinstr_replacement,\"ax\"\n"		\
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| 		      "663:\n\t" newinstr "\n664:\n"   /* replacement */ \
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| 		      ".previous" :: "i" (feature) : "memory")  
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| 
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| /*
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|  * Alternative inline assembly with input.
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|  * 
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|  * Peculiarities:
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|  * No memory clobber here. 
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|  * Argument numbers start with 1.
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|  * Best is to use constraints that are fixed size (like (%1) ... "r")
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|  * If you use variable sized constraints like "m" or "g" in the 
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|  * replacement make sure to pad to the worst case length.
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|  */
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| #define alternative_input(oldinstr, newinstr, feature, input...)	\
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| 	asm volatile ("661:\n\t" oldinstr "\n662:\n"			\
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| 		      ".section .altinstructions,\"a\"\n"		\
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| 		      "  .align 8\n"					\
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| 		      "  .quad 661b\n"            /* label */		\
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| 		      "  .quad 663f\n"		  /* new instruction */	\
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| 		      "  .byte %c0\n"             /* feature bit */	\
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| 		      "  .byte 662b-661b\n"       /* sourcelen */	\
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| 		      "  .byte 664f-663f\n"       /* replacementlen */	\
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| 		      ".previous\n"					\
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| 		      ".section .altinstr_replacement,\"ax\"\n"		\
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| 		      "663:\n\t" newinstr "\n664:\n"   /* replacement */ \
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| 		      ".previous" :: "i" (feature), ##input)
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| 
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| /* Like alternative_input, but with a single output argument */
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| #define alternative_io(oldinstr, newinstr, feature, output, input...) \
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| 	asm volatile ("661:\n\t" oldinstr "\n662:\n"			\
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| 		      ".section .altinstructions,\"a\"\n"		\
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| 		      "  .align 8\n"					\
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| 		      "  .quad 661b\n"            /* label */		\
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| 		      "  .quad 663f\n"		  /* new instruction */	\
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| 		      "  .byte %c[feat]\n"        /* feature bit */	\
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| 		      "  .byte 662b-661b\n"       /* sourcelen */	\
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| 		      "  .byte 664f-663f\n"       /* replacementlen */	\
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| 		      ".previous\n"					\
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| 		      ".section .altinstr_replacement,\"ax\"\n"		\
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| 		      "663:\n\t" newinstr "\n664:\n"   /* replacement */ \
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| 		      ".previous" : output : [feat] "i" (feature), ##input)
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| 
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| /*
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|  * Clear and set 'TS' bit respectively
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|  */
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| #define clts() __asm__ __volatile__ ("clts")
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| 
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| static inline unsigned long read_cr0(void)
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| { 
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| 	unsigned long cr0;
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| 	asm volatile("movq %%cr0,%0" : "=r" (cr0));
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| 	return cr0;
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| } 
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| 
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| static inline void write_cr0(unsigned long val) 
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| { 
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| 	asm volatile("movq %0,%%cr0" :: "r" (val));
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| } 
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| 
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| static inline unsigned long read_cr3(void)
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| { 
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| 	unsigned long cr3;
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| 	asm("movq %%cr3,%0" : "=r" (cr3));
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| 	return cr3;
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| } 
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| 
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| static inline unsigned long read_cr4(void)
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| { 
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| 	unsigned long cr4;
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| 	asm("movq %%cr4,%0" : "=r" (cr4));
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| 	return cr4;
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| } 
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| 
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| static inline void write_cr4(unsigned long val)
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| { 
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| 	asm volatile("movq %0,%%cr4" :: "r" (val));
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| } 
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| 
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| #define stts() write_cr0(8 | read_cr0())
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| 
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| #define wbinvd() \
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| 	__asm__ __volatile__ ("wbinvd": : :"memory");
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| 
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| /*
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|  * On SMP systems, when the scheduler does migration-cost autodetection,
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|  * it needs a way to flush as much of the CPU's caches as possible.
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|  */
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| static inline void sched_cacheflush(void)
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| {
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| 	wbinvd();
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| }
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| 
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| #endif	/* __KERNEL__ */
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| 
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| #define nop() __asm__ __volatile__ ("nop")
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| 
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| #define xchg(ptr,v) ((__typeof__(*(ptr)))__xchg((unsigned long)(v),(ptr),sizeof(*(ptr))))
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| 
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| #define tas(ptr) (xchg((ptr),1))
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| 
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| #define __xg(x) ((volatile long *)(x))
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| 
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| static inline void set_64bit(volatile unsigned long *ptr, unsigned long val)
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| {
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| 	*ptr = val;
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| }
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| 
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| #define _set_64bit set_64bit
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| 
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| /*
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|  * Note: no "lock" prefix even on SMP: xchg always implies lock anyway
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|  * Note 2: xchg has side effect, so that attribute volatile is necessary,
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|  *	  but generally the primitive is invalid, *ptr is output argument. --ANK
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|  */
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| static inline unsigned long __xchg(unsigned long x, volatile void * ptr, int size)
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| {
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| 	switch (size) {
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| 		case 1:
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| 			__asm__ __volatile__("xchgb %b0,%1"
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| 				:"=q" (x)
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| 				:"m" (*__xg(ptr)), "0" (x)
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| 				:"memory");
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| 			break;
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| 		case 2:
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| 			__asm__ __volatile__("xchgw %w0,%1"
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| 				:"=r" (x)
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| 				:"m" (*__xg(ptr)), "0" (x)
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| 				:"memory");
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| 			break;
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| 		case 4:
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| 			__asm__ __volatile__("xchgl %k0,%1"
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| 				:"=r" (x)
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| 				:"m" (*__xg(ptr)), "0" (x)
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| 				:"memory");
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| 			break;
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| 		case 8:
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| 			__asm__ __volatile__("xchgq %0,%1"
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| 				:"=r" (x)
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| 				:"m" (*__xg(ptr)), "0" (x)
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| 				:"memory");
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| 			break;
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| 	}
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| 	return x;
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| }
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| 
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| /*
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|  * Atomic compare and exchange.  Compare OLD with MEM, if identical,
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|  * store NEW in MEM.  Return the initial value in MEM.  Success is
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|  * indicated by comparing RETURN with OLD.
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|  */
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| 
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| #define __HAVE_ARCH_CMPXCHG 1
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| 
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| static inline unsigned long __cmpxchg(volatile void *ptr, unsigned long old,
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| 				      unsigned long new, int size)
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| {
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| 	unsigned long prev;
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| 	switch (size) {
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| 	case 1:
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| 		__asm__ __volatile__(LOCK_PREFIX "cmpxchgb %b1,%2"
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| 				     : "=a"(prev)
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| 				     : "q"(new), "m"(*__xg(ptr)), "0"(old)
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| 				     : "memory");
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| 		return prev;
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| 	case 2:
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| 		__asm__ __volatile__(LOCK_PREFIX "cmpxchgw %w1,%2"
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| 				     : "=a"(prev)
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| 				     : "r"(new), "m"(*__xg(ptr)), "0"(old)
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| 				     : "memory");
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| 		return prev;
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| 	case 4:
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| 		__asm__ __volatile__(LOCK_PREFIX "cmpxchgl %k1,%2"
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| 				     : "=a"(prev)
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| 				     : "r"(new), "m"(*__xg(ptr)), "0"(old)
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| 				     : "memory");
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| 		return prev;
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| 	case 8:
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| 		__asm__ __volatile__(LOCK_PREFIX "cmpxchgq %1,%2"
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| 				     : "=a"(prev)
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| 				     : "r"(new), "m"(*__xg(ptr)), "0"(old)
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| 				     : "memory");
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| 		return prev;
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| 	}
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| 	return old;
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| }
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| 
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| #define cmpxchg(ptr,o,n)\
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| 	((__typeof__(*(ptr)))__cmpxchg((ptr),(unsigned long)(o),\
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| 					(unsigned long)(n),sizeof(*(ptr))))
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| 
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| #ifdef CONFIG_SMP
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| #define smp_mb()	mb()
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| #define smp_rmb()	rmb()
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| #define smp_wmb()	wmb()
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| #define smp_read_barrier_depends()	do {} while(0)
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| #else
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| #define smp_mb()	barrier()
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| #define smp_rmb()	barrier()
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| #define smp_wmb()	barrier()
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| #define smp_read_barrier_depends()	do {} while(0)
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| #endif
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| 
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|     
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| /*
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|  * Force strict CPU ordering.
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|  * And yes, this is required on UP too when we're talking
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|  * to devices.
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|  */
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| #define mb() 	asm volatile("mfence":::"memory")
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| #define rmb()	asm volatile("lfence":::"memory")
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| 
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| #ifdef CONFIG_UNORDERED_IO
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| #define wmb()	asm volatile("sfence" ::: "memory")
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| #else
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| #define wmb()	asm volatile("" ::: "memory")
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| #endif
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| #define read_barrier_depends()	do {} while(0)
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| #define set_mb(var, value) do { xchg(&var, value); } while (0)
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| #define set_wmb(var, value) do { var = value; wmb(); } while (0)
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| 
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| #define warn_if_not_ulong(x) do { unsigned long foo; (void) (&(x) == &foo); } while (0)
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| 
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| /* interrupt control.. */
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| #define local_save_flags(x)	do { warn_if_not_ulong(x); __asm__ __volatile__("# save_flags \n\t pushfq ; popq %q0":"=g" (x): /* no input */ :"memory"); } while (0)
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| #define local_irq_restore(x) 	__asm__ __volatile__("# restore_flags \n\t pushq %0 ; popfq": /* no output */ :"g" (x):"memory", "cc")
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| 
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| #ifdef CONFIG_X86_VSMP
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| /* Interrupt control for VSMP  architecture */
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| #define local_irq_disable()	do { unsigned long flags; local_save_flags(flags); local_irq_restore((flags & ~(1 << 9)) | (1 << 18)); } while (0)
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| #define local_irq_enable()	do { unsigned long flags; local_save_flags(flags); local_irq_restore((flags | (1 << 9)) & ~(1 << 18)); } while (0)
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| 
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| #define irqs_disabled()					\
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| ({							\
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| 	unsigned long flags;				\
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| 	local_save_flags(flags);			\
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| 	(flags & (1<<18)) || !(flags & (1<<9));		\
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| })
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| 
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| /* For spinlocks etc */
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| #define local_irq_save(x)	do { local_save_flags(x); local_irq_restore((x & ~(1 << 9)) | (1 << 18)); } while (0)
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| #else  /* CONFIG_X86_VSMP */
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| #define local_irq_disable() 	__asm__ __volatile__("cli": : :"memory")
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| #define local_irq_enable()	__asm__ __volatile__("sti": : :"memory")
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| 
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| /* used in the idle loop; sti takes one instruction cycle to complete */
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| #define safe_halt()		__asm__ __volatile__("sti; hlt": : :"memory")
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| /* used when interrupts are already enabled or to shutdown the processor */
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| #define halt()			__asm__ __volatile__("hlt": : :"memory")
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| 
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| #define irqs_disabled()			\
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| ({					\
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| 	unsigned long flags;		\
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| 	local_save_flags(flags);	\
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| 	!(flags & (1<<9));		\
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| })
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| 
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| /* For spinlocks etc */
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| #define local_irq_save(x) 	do { warn_if_not_ulong(x); __asm__ __volatile__("# local_irq_save \n\t pushfq ; popq %0 ; cli":"=g" (x): /* no input */ :"memory"); } while (0)
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| #endif
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| 
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| void cpu_idle_wait(void);
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| 
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| extern unsigned long arch_align_stack(unsigned long sp);
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| 
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| #endif
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