[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] [Xen-merge] [PATCH 18/23] system asm subarch headers
--- linux-2.6.12-xen0-arch.orig/arch/i386/kernel/traps.c +++ linux-2.6.12-xen0-arch/arch/i386/kernel/traps.c @@ -988,20 +988,6 @@ void __init trap_init_f00f_bug(void) } #endif -#define _set_gate(gate_addr,type,dpl,addr,seg) \ -do { \ - int __d0, __d1; \ - __asm__ __volatile__ ("movw %%dx,%%ax\n\t" \ - "movw %4,%%dx\n\t" \ - "movl %%eax,%0\n\t" \ - "movl %%edx,%1" \ - :"=m" (*((long *) (gate_addr))), \ - "=m" (*(1+(long *) (gate_addr))), "=&a" (__d0), "=&d" (__d1) \ - :"i" ((short) (0x8000+(dpl<<13)+(type<<8))), \ - "3" ((char *) (addr)),"2" ((seg) << 16)); \ -} while (0) - - /* * This needs to use 'idt_table' rather than 'idt', and * thus use the _nonmapped_ version of the IDT, as the --- linux-2.6.12-xen0-arch.orig/include/asm-i386/system.h +++ linux-2.6.12-xen0-arch/include/asm-i386/system.h @@ -1,517 +1,6 @@ #ifndef __ASM_SYSTEM_H #define __ASM_SYSTEM_H -#include <linux/config.h> -#include <linux/kernel.h> -#include <asm/segment.h> -#include <asm/cpufeature.h> -#include <asm/smp_alt.h> - -#ifdef __KERNEL__ - -struct task_struct; /* one of the stranger aspects of C forward declarations.. */ -extern struct task_struct * FASTCALL(__switch_to(struct task_struct *prev, struct task_struct *next)); - -#define switch_to(prev,next,last) do { \ - unsigned long esi,edi; \ - asm volatile("pushfl\n\t" \ - "pushl %%ebp\n\t" \ - "movl %%esp,%0\n\t" /* save ESP */ \ - "movl %5,%%esp\n\t" /* restore ESP */ \ - "movl $1f,%1\n\t" /* save EIP */ \ - "pushl %6\n\t" /* restore EIP */ \ - "jmp __switch_to\n" \ - "1:\t" \ - "popl %%ebp\n\t" \ - "popfl" \ - :"=m" (prev->thread.esp),"=m" (prev->thread.eip), \ - "=a" (last),"=S" (esi),"=D" (edi) \ - :"m" (next->thread.esp),"m" (next->thread.eip), \ - "2" (prev), "d" (next)); \ -} while (0) - -#define _set_base(addr,base) do { unsigned long __pr; \ -__asm__ __volatile__ ("movw %%dx,%1\n\t" \ - "rorl $16,%%edx\n\t" \ - "movb %%dl,%2\n\t" \ - "movb %%dh,%3" \ - :"=&d" (__pr) \ - :"m" (*((addr)+2)), \ - "m" (*((addr)+4)), \ - "m" (*((addr)+7)), \ - "0" (base) \ - ); } while(0) - -#define _set_limit(addr,limit) do { unsigned long __lr; \ -__asm__ __volatile__ ("movw %%dx,%1\n\t" \ - "rorl $16,%%edx\n\t" \ - "movb %2,%%dh\n\t" \ - "andb $0xf0,%%dh\n\t" \ - "orb %%dh,%%dl\n\t" \ - "movb %%dl,%2" \ - :"=&d" (__lr) \ - :"m" (*(addr)), \ - "m" (*((addr)+6)), \ - "0" (limit) \ - ); } while(0) - -#define set_base(ldt,base) _set_base( ((char *)&(ldt)) , (base) ) -#define set_limit(ldt,limit) _set_limit( ((char *)&(ldt)) , ((limit)-1)>>12 ) - -static inline unsigned long _get_base(char * addr) -{ - unsigned long __base; - __asm__("movb %3,%%dh\n\t" - "movb %2,%%dl\n\t" - "shll $16,%%edx\n\t" - "movw %1,%%dx" - :"=&d" (__base) - :"m" (*((addr)+2)), - "m" (*((addr)+4)), - "m" (*((addr)+7))); - return __base; -} - -#define get_base(ldt) _get_base( ((char *)&(ldt)) ) - -/* - * Load a segment. Fall back on loading the zero - * segment if something goes wrong.. - */ -#define loadsegment(seg,value) \ - asm volatile("\n" \ - "1:\t" \ - "mov %0,%%" #seg "\n" \ - "2:\n" \ - ".section .fixup,\"ax\"\n" \ - "3:\t" \ - "pushl $0\n\t" \ - "popl %%" #seg "\n\t" \ - "jmp 2b\n" \ - ".previous\n" \ - ".section __ex_table,\"a\"\n\t" \ - ".align 4\n\t" \ - ".long 1b,3b\n" \ - ".previous" \ - : :"m" (value)) - -/* - * Save a segment register away - */ -#define savesegment(seg, value) \ - asm volatile("mov %%" #seg ",%0":"=m" (value)) - -/* - * Clear and set 'TS' bit respectively - */ -#define clts() __asm__ __volatile__ ("clts") -#define read_cr0() ({ \ - unsigned int __dummy; \ - __asm__( \ - "movl %%cr0,%0\n\t" \ - :"=r" (__dummy)); \ - __dummy; \ -}) -#define write_cr0(x) \ - __asm__("movl %0,%%cr0": :"r" (x)); - -#define read_cr4() ({ \ - unsigned int __dummy; \ - __asm__( \ - "movl %%cr4,%0\n\t" \ - :"=r" (__dummy)); \ - __dummy; \ -}) -#define write_cr4(x) \ - __asm__("movl %0,%%cr4": :"r" (x)); -#define stts() write_cr0(8 | read_cr0()) - -#endif /* __KERNEL__ */ - -#define wbinvd() \ - __asm__ __volatile__ ("wbinvd": : :"memory"); - -static inline unsigned long get_limit(unsigned long segment) -{ - unsigned long __limit; - __asm__("lsll %1,%0" - :"=r" (__limit):"r" (segment)); - return __limit+1; -} - -#define nop() __asm__ __volatile__ ("nop") - -#define xchg(ptr,v) ((__typeof__(*(ptr)))__xchg((unsigned long)(v),(ptr),sizeof(*(ptr)))) - -#define tas(ptr) (xchg((ptr),1)) - -struct __xchg_dummy { unsigned long a[100]; }; -#define __xg(x) ((struct __xchg_dummy *)(x)) - - -/* - * The semantics of XCHGCMP8B are a bit strange, this is why - * there is a loop and the loading of %%eax and %%edx has to - * be inside. This inlines well in most cases, the cached - * cost is around ~38 cycles. (in the future we might want - * to do an SIMD/3DNOW!/MMX/FPU 64-bit store here, but that - * might have an implicit FPU-save as a cost, so it's not - * clear which path to go.) - * - * cmpxchg8b must be used with the lock prefix here to allow - * the instruction to be executed atomically, see page 3-102 - * of the instruction set reference 24319102.pdf. We need - * the reader side to see the coherent 64bit value. - */ -static inline void __set_64bit (unsigned long long * ptr, - unsigned int low, unsigned int high) -{ - __asm__ __volatile__ ( - "\n1:\t" - "movl (%0), %%eax\n\t" - "movl 4(%0), %%edx\n\t" - "lock cmpxchg8b (%0)\n\t" - "jnz 1b" - : /* no outputs */ - : "D"(ptr), - "b"(low), - "c"(high) - : "ax","dx","memory"); -} - -static inline void __set_64bit_constant (unsigned long long *ptr, - unsigned long long value) -{ - __set_64bit(ptr,(unsigned int)(value), (unsigned int)((value)>>32ULL)); -} -#define ll_low(x) *(((unsigned int*)&(x))+0) -#define ll_high(x) *(((unsigned int*)&(x))+1) - -static inline void __set_64bit_var (unsigned long long *ptr, - unsigned long long value) -{ - __set_64bit(ptr,ll_low(value), ll_high(value)); -} - -#define set_64bit(ptr,value) \ -(__builtin_constant_p(value) ? \ - __set_64bit_constant(ptr, value) : \ - __set_64bit_var(ptr, value) ) - -#define _set_64bit(ptr,value) \ -(__builtin_constant_p(value) ? \ - __set_64bit(ptr, (unsigned int)(value), (unsigned int)((value)>>32ULL) ) : \ - __set_64bit(ptr, ll_low(value), ll_high(value)) ) - -/* - * Note: no "lock" prefix even on SMP: xchg always implies lock anyway - * Note 2: xchg has side effect, so that attribute volatile is necessary, - * but generally the primitive is invalid, *ptr is output argument. --ANK - */ -static inline unsigned long __xchg(unsigned long x, volatile void * ptr, int size) -{ - switch (size) { - case 1: - __asm__ __volatile__("xchgb %b0,%1" - :"=q" (x) - :"m" (*__xg(ptr)), "0" (x) - :"memory"); - break; - case 2: - __asm__ __volatile__("xchgw %w0,%1" - :"=r" (x) - :"m" (*__xg(ptr)), "0" (x) - :"memory"); - break; - case 4: - __asm__ __volatile__("xchgl %0,%1" - :"=r" (x) - :"m" (*__xg(ptr)), "0" (x) - :"memory"); - break; - } - return x; -} - -/* - * Atomic compare and exchange. Compare OLD with MEM, if identical, - * store NEW in MEM. Return the initial value in MEM. Success is - * indicated by comparing RETURN with OLD. - */ - -#ifdef CONFIG_X86_CMPXCHG -#define __HAVE_ARCH_CMPXCHG 1 -#endif - -static inline unsigned long __cmpxchg(volatile void *ptr, unsigned long old, - unsigned long new, int size) -{ - unsigned long prev; - switch (size) { - case 1: - __asm__ __volatile__(LOCK "cmpxchgb %b1,%2" - : "=a"(prev) - : "q"(new), "m"(*__xg(ptr)), "0"(old) - : "memory"); - return prev; - case 2: - __asm__ __volatile__(LOCK "cmpxchgw %w1,%2" - : "=a"(prev) - : "q"(new), "m"(*__xg(ptr)), "0"(old) - : "memory"); - return prev; - case 4: - __asm__ __volatile__(LOCK "cmpxchgl %1,%2" - : "=a"(prev) - : "q"(new), "m"(*__xg(ptr)), "0"(old) - : "memory"); - return prev; - } - return old; -} - -#define cmpxchg(ptr,o,n)\ - ((__typeof__(*(ptr)))__cmpxchg((ptr),(unsigned long)(o),\ - (unsigned long)(n),sizeof(*(ptr)))) - -#ifdef __KERNEL__ -struct alt_instr { - __u8 *instr; /* original instruction */ - __u8 *replacement; - __u8 cpuid; /* cpuid bit set for replacement */ - __u8 instrlen; /* length of original instruction */ - __u8 replacementlen; /* length of new instruction, <= instrlen */ - __u8 pad; -}; -#endif - -/* - * Alternative instructions for different CPU types or capabilities. - * - * This allows to use optimized instructions even on generic binary - * kernels. - * - * length of oldinstr must be longer or equal the length of newinstr - * It can be padded with nops as needed. - * - * For non barrier like inlines please define new variants - * without volatile and memory clobber. - */ -#define alternative(oldinstr, newinstr, feature) \ - asm volatile ("661:\n\t" oldinstr "\n662:\n" \ - ".section .altinstructions,\"a\"\n" \ - " .align 4\n" \ - " .long 661b\n" /* label */ \ - " .long 663f\n" /* new instruction */ \ - " .byte %c0\n" /* feature bit */ \ - " .byte 662b-661b\n" /* sourcelen */ \ - " .byte 664f-663f\n" /* replacementlen */ \ - ".previous\n" \ - ".section .altinstr_replacement,\"ax\"\n" \ - "663:\n\t" newinstr "\n664:\n" /* replacement */ \ - ".previous" :: "i" (feature) : "memory") - -/* - * Alternative inline assembly with input. - * - * Pecularities: - * No memory clobber here. - * Argument numbers start with 1. - * Best is to use constraints that are fixed size (like (%1) ... "r") - * If you use variable sized constraints like "m" or "g" in the - * replacement maake sure to pad to the worst case length. - */ -#define alternative_input(oldinstr, newinstr, feature, input...) \ - asm volatile ("661:\n\t" oldinstr "\n662:\n" \ - ".section .altinstructions,\"a\"\n" \ - " .align 4\n" \ - " .long 661b\n" /* label */ \ - " .long 663f\n" /* new instruction */ \ - " .byte %c0\n" /* feature bit */ \ - " .byte 662b-661b\n" /* sourcelen */ \ - " .byte 664f-663f\n" /* replacementlen */ \ - ".previous\n" \ - ".section .altinstr_replacement,\"ax\"\n" \ - "663:\n\t" newinstr "\n664:\n" /* replacement */ \ - ".previous" :: "i" (feature), ##input) - -/* - * Force strict CPU ordering. - * And yes, this is required on UP too when we're talking - * to devices. - * - * For now, "wmb()" doesn't actually do anything, as all - * Intel CPU's follow what Intel calls a *Processor Order*, - * in which all writes are seen in the program order even - * outside the CPU. - * - * I expect future Intel CPU's to have a weaker ordering, - * but I'd also expect them to finally get their act together - * and add some real memory barriers if so. - * - * Some non intel clones support out of order store. wmb() ceases to be a - * nop for these. - */ - - -/* - * Actually only lfence would be needed for mb() because all stores done - * by the kernel should be already ordered. But keep a full barrier for now. - */ - -#define mb() alternative("lock; addl $0,0(%%esp)", "mfence", X86_FEATURE_XMM2) -#define rmb() alternative("lock; addl $0,0(%%esp)", "lfence", X86_FEATURE_XMM2) - -/** - * read_barrier_depends - Flush all pending reads that subsequents reads - * depend on. - * - * No data-dependent reads from memory-like regions are ever reordered - * over this barrier. All reads preceding this primitive are guaranteed - * to access memory (but not necessarily other CPUs' caches) before any - * reads following this primitive that depend on the data return by - * any of the preceding reads. This primitive is much lighter weight than - * rmb() on most CPUs, and is never heavier weight than is - * rmb(). - * - * These ordering constraints are respected by both the local CPU - * and the compiler. - * - * Ordering is not guaranteed by anything other than these primitives, - * not even by data dependencies. See the documentation for - * memory_barrier() for examples and URLs to more information. - * - * For example, the following code would force ordering (the initial - * value of "a" is zero, "b" is one, and "p" is "&a"): - * - * <programlisting> - * CPU 0 CPU 1 - * - * b = 2; - * memory_barrier(); - * p = &b; q = p; - * read_barrier_depends(); - * d = *q; - * </programlisting> - * - * because the read of "*q" depends on the read of "p" and these - * two reads are separated by a read_barrier_depends(). However, - * the following code, with the same initial values for "a" and "b": - * - * <programlisting> - * CPU 0 CPU 1 - * - * a = 2; - * memory_barrier(); - * b = 3; y = b; - * read_barrier_depends(); - * x = a; - * </programlisting> - * - * does not enforce ordering, since there is no data dependency between - * the read of "a" and the read of "b". Therefore, on some CPUs, such - * as Alpha, "y" could be set to 3 and "x" to 0. Use rmb() - * in cases like thiswhere there are no data dependencies. - **/ - -#define read_barrier_depends() do { } while(0) - -#ifdef CONFIG_X86_OOSTORE -/* Actually there are no OOO store capable CPUs for now that do SSE, - but make it already an possibility. */ -#define wmb() alternative("lock; addl $0,0(%%esp)", "sfence", X86_FEATURE_XMM) -#else -#define wmb() __asm__ __volatile__ ("": : :"memory") -#endif - -#ifdef CONFIG_SMP -#define smp_wmb() wmb() -#if defined(CONFIG_SMP_ALTERNATIVES) && !defined(MODULE) -#define smp_alt_mb(instr) \ -__asm__ __volatile__("6667:\nnop\nnop\nnop\nnop\nnop\nnop\n6668:\n" \ - ".section __smp_alternatives,\"a\"\n" \ - ".long 6667b\n" \ - ".long 6673f\n" \ - ".previous\n" \ - ".section __smp_replacements,\"a\"\n" \ - "6673:.byte 6668b-6667b\n" \ - ".byte 6670f-6669f\n" \ - ".byte 6671f-6670f\n" \ - ".byte 0\n" \ - ".byte %c0\n" \ - "6669:lock;addl $0,0(%%esp)\n" \ - "6670:" instr "\n" \ - "6671:\n" \ - ".previous\n" \ - : \ - : "i" (X86_FEATURE_XMM2) \ - : "memory") -#define smp_rmb() smp_alt_mb("lfence") -#define smp_mb() smp_alt_mb("mfence") -#define set_mb(var, value) do { \ -unsigned long __set_mb_temp; \ -__asm__ __volatile__("6667:movl %1, %0\n6668:\n" \ - ".section __smp_alternatives,\"a\"\n" \ - ".long 6667b\n" \ - ".long 6673f\n" \ - ".previous\n" \ - ".section __smp_replacements,\"a\"\n" \ - "6673: .byte 6668b-6667b\n" \ - ".byte 6670f-6669f\n" \ - ".byte 0\n" \ - ".byte 6671f-6670f\n" \ - ".byte -1\n" \ - "6669: xchg %1, %0\n" \ - "6670:movl %1, %0\n" \ - "6671:\n" \ - ".previous\n" \ - : "=m" (var), "=r" (__set_mb_temp) \ - : "1" (value) \ - : "memory"); } while (0) -#else -#define smp_rmb() rmb() -#define smp_mb() mb() -#define set_mb(var, value) do { xchg(&var, value); } while (0) -#endif -#define smp_read_barrier_depends() read_barrier_depends() -#else -#define smp_mb() barrier() -#define smp_rmb() barrier() -#define smp_wmb() barrier() -#define smp_read_barrier_depends() do { } while(0) -#define set_mb(var, value) do { var = value; barrier(); } while (0) -#endif - -#define set_wmb(var, value) do { var = value; wmb(); } while (0) - -/* interrupt control.. */ -#define local_save_flags(x) do { typecheck(unsigned long,x); __asm__ __volatile__("pushfl ; popl %0":"=g" (x): /* no input */); } while (0) -#define local_irq_restore(x) do { typecheck(unsigned long,x); __asm__ __volatile__("pushl %0 ; popfl": /* no output */ :"g" (x):"memory", "cc"); } while (0) -#define local_irq_disable() __asm__ __volatile__("cli": : :"memory") -#define local_irq_enable() __asm__ __volatile__("sti": : :"memory") -/* used in the idle loop; sti takes one instruction cycle to complete */ -#define safe_halt() __asm__ __volatile__("sti; hlt": : :"memory") - -#define irqs_disabled() \ -({ \ - unsigned long flags; \ - local_save_flags(flags); \ - !(flags & (1<<9)); \ -}) - -/* For spinlocks etc */ -#define local_irq_save(x) __asm__ __volatile__("pushfl ; popl %0 ; cli":"=g" (x): /* no input */ :"memory") - -/* - * disable hlt during certain critical i/o operations - */ -#define HAVE_DISABLE_HLT -void disable_hlt(void); -void enable_hlt(void); - -extern int es7000_plat; -void cpu_idle_wait(void); - -extern unsigned long arch_align_stack(unsigned long sp); +#include <mach_system.h> #endif --- /dev/null +++ linux-2.6.12-xen0-arch/include/asm-i386/mach-default/mach_system.h @@ -0,0 +1,530 @@ +#ifndef __ASM_MACH_SYSTEM_H +#define __ASM_MACH_SYSTEM_H + +#include <linux/config.h> +#include <linux/kernel.h> +#include <asm/segment.h> +#include <asm/cpufeature.h> +#include <asm/smp_alt.h> + +#ifdef __KERNEL__ + +struct task_struct; /* one of the stranger aspects of C forward declarations.. */ +extern struct task_struct * FASTCALL(__switch_to(struct task_struct *prev, struct task_struct *next)); + +#define switch_to(prev,next,last) do { \ + unsigned long esi,edi; \ + asm volatile("pushfl\n\t" \ + "pushl %%ebp\n\t" \ + "movl %%esp,%0\n\t" /* save ESP */ \ + "movl %5,%%esp\n\t" /* restore ESP */ \ + "movl $1f,%1\n\t" /* save EIP */ \ + "pushl %6\n\t" /* restore EIP */ \ + "jmp __switch_to\n" \ + "1:\t" \ + "popl %%ebp\n\t" \ + "popfl" \ + :"=m" (prev->thread.esp),"=m" (prev->thread.eip), \ + "=a" (last),"=S" (esi),"=D" (edi) \ + :"m" (next->thread.esp),"m" (next->thread.eip), \ + "2" (prev), "d" (next)); \ +} while (0) + +#define _set_base(addr,base) do { unsigned long __pr; \ +__asm__ __volatile__ ("movw %%dx,%1\n\t" \ + "rorl $16,%%edx\n\t" \ + "movb %%dl,%2\n\t" \ + "movb %%dh,%3" \ + :"=&d" (__pr) \ + :"m" (*((addr)+2)), \ + "m" (*((addr)+4)), \ + "m" (*((addr)+7)), \ + "0" (base) \ + ); } while(0) + +#define _set_limit(addr,limit) do { unsigned long __lr; \ +__asm__ __volatile__ ("movw %%dx,%1\n\t" \ + "rorl $16,%%edx\n\t" \ + "movb %2,%%dh\n\t" \ + "andb $0xf0,%%dh\n\t" \ + "orb %%dh,%%dl\n\t" \ + "movb %%dl,%2" \ + :"=&d" (__lr) \ + :"m" (*(addr)), \ + "m" (*((addr)+6)), \ + "0" (limit) \ + ); } while(0) + +#define set_base(ldt,base) _set_base( ((char *)&(ldt)) , (base) ) +#define set_limit(ldt,limit) _set_limit( ((char *)&(ldt)) , ((limit)-1)>>12 ) + +static inline unsigned long _get_base(char * addr) +{ + unsigned long __base; + __asm__("movb %3,%%dh\n\t" + "movb %2,%%dl\n\t" + "shll $16,%%edx\n\t" + "movw %1,%%dx" + :"=&d" (__base) + :"m" (*((addr)+2)), + "m" (*((addr)+4)), + "m" (*((addr)+7))); + return __base; +} + +#define get_base(ldt) _get_base( ((char *)&(ldt)) ) + +#define _set_gate(gate_addr,type,dpl,addr,seg) \ +do { \ + int __d0, __d1; \ + __asm__ __volatile__ ("movw %%dx,%%ax\n\t" \ + "movw %4,%%dx\n\t" \ + "movl %%eax,%0\n\t" \ + "movl %%edx,%1" \ + :"=m" (*((long *) (gate_addr))), \ + "=m" (*(1+(long *) (gate_addr))), "=&a" (__d0), "=&d" (__d1) \ + :"i" ((short) (0x8000+(dpl<<13)+(type<<8))), \ + "3" ((char *) (addr)),"2" ((seg) << 16)); \ +} while (0) + +/* + * Load a segment. Fall back on loading the zero + * segment if something goes wrong.. + */ +#define loadsegment(seg,value) \ + asm volatile("\n" \ + "1:\t" \ + "mov %0,%%" #seg "\n" \ + "2:\n" \ + ".section .fixup,\"ax\"\n" \ + "3:\t" \ + "pushl $0\n\t" \ + "popl %%" #seg "\n\t" \ + "jmp 2b\n" \ + ".previous\n" \ + ".section __ex_table,\"a\"\n\t" \ + ".align 4\n\t" \ + ".long 1b,3b\n" \ + ".previous" \ + : :"m" (value)) + +/* + * Save a segment register away + */ +#define savesegment(seg, value) \ + asm volatile("mov %%" #seg ",%0":"=m" (value)) + +/* + * Clear and set 'TS' bit respectively + */ +#define clts() __asm__ __volatile__ ("clts") +#define read_cr0() ({ \ + unsigned int __dummy; \ + __asm__( \ + "movl %%cr0,%0\n\t" \ + :"=r" (__dummy)); \ + __dummy; \ +}) +#define write_cr0(x) \ + __asm__("movl %0,%%cr0": :"r" (x)); + +#define read_cr4() ({ \ + unsigned int __dummy; \ + __asm__( \ + "movl %%cr4,%0\n\t" \ + :"=r" (__dummy)); \ + __dummy; \ +}) +#define write_cr4(x) \ + __asm__("movl %0,%%cr4": :"r" (x)); +#define stts() write_cr0(8 | read_cr0()) + +#endif /* __KERNEL__ */ + +#define wbinvd() \ + __asm__ __volatile__ ("wbinvd": : :"memory"); + +static inline unsigned long get_limit(unsigned long segment) +{ + unsigned long __limit; + __asm__("lsll %1,%0" + :"=r" (__limit):"r" (segment)); + return __limit+1; +} + +#define nop() __asm__ __volatile__ ("nop") + +#define xchg(ptr,v) ((__typeof__(*(ptr)))__xchg((unsigned long)(v),(ptr),sizeof(*(ptr)))) + +#define tas(ptr) (xchg((ptr),1)) + +struct __xchg_dummy { unsigned long a[100]; }; +#define __xg(x) ((struct __xchg_dummy *)(x)) + + +/* + * The semantics of XCHGCMP8B are a bit strange, this is why + * there is a loop and the loading of %%eax and %%edx has to + * be inside. This inlines well in most cases, the cached + * cost is around ~38 cycles. (in the future we might want + * to do an SIMD/3DNOW!/MMX/FPU 64-bit store here, but that + * might have an implicit FPU-save as a cost, so it's not + * clear which path to go.) + * + * cmpxchg8b must be used with the lock prefix here to allow + * the instruction to be executed atomically, see page 3-102 + * of the instruction set reference 24319102.pdf. We need + * the reader side to see the coherent 64bit value. + */ +static inline void __set_64bit (unsigned long long * ptr, + unsigned int low, unsigned int high) +{ + __asm__ __volatile__ ( + "\n1:\t" + "movl (%0), %%eax\n\t" + "movl 4(%0), %%edx\n\t" + "lock cmpxchg8b (%0)\n\t" + "jnz 1b" + : /* no outputs */ + : "D"(ptr), + "b"(low), + "c"(high) + : "ax","dx","memory"); +} + +static inline void __set_64bit_constant (unsigned long long *ptr, + unsigned long long value) +{ + __set_64bit(ptr,(unsigned int)(value), (unsigned int)((value)>>32ULL)); +} +#define ll_low(x) *(((unsigned int*)&(x))+0) +#define ll_high(x) *(((unsigned int*)&(x))+1) + +static inline void __set_64bit_var (unsigned long long *ptr, + unsigned long long value) +{ + __set_64bit(ptr,ll_low(value), ll_high(value)); +} + +#define set_64bit(ptr,value) \ +(__builtin_constant_p(value) ? \ + __set_64bit_constant(ptr, value) : \ + __set_64bit_var(ptr, value) ) + +#define _set_64bit(ptr,value) \ +(__builtin_constant_p(value) ? \ + __set_64bit(ptr, (unsigned int)(value), (unsigned int)((value)>>32ULL) ) : \ + __set_64bit(ptr, ll_low(value), ll_high(value)) ) + +/* + * Note: no "lock" prefix even on SMP: xchg always implies lock anyway + * Note 2: xchg has side effect, so that attribute volatile is necessary, + * but generally the primitive is invalid, *ptr is output argument. --ANK + */ +static inline unsigned long __xchg(unsigned long x, volatile void * ptr, int size) +{ + switch (size) { + case 1: + __asm__ __volatile__("xchgb %b0,%1" + :"=q" (x) + :"m" (*__xg(ptr)), "0" (x) + :"memory"); + break; + case 2: + __asm__ __volatile__("xchgw %w0,%1" + :"=r" (x) + :"m" (*__xg(ptr)), "0" (x) + :"memory"); + break; + case 4: + __asm__ __volatile__("xchgl %0,%1" + :"=r" (x) + :"m" (*__xg(ptr)), "0" (x) + :"memory"); + break; + } + return x; +} + +/* + * Atomic compare and exchange. Compare OLD with MEM, if identical, + * store NEW in MEM. Return the initial value in MEM. Success is + * indicated by comparing RETURN with OLD. + */ + +#ifdef CONFIG_X86_CMPXCHG +#define __HAVE_ARCH_CMPXCHG 1 +#endif + +static inline unsigned long __cmpxchg(volatile void *ptr, unsigned long old, + unsigned long new, int size) +{ + unsigned long prev; + switch (size) { + case 1: + __asm__ __volatile__(LOCK "cmpxchgb %b1,%2" + : "=a"(prev) + : "q"(new), "m"(*__xg(ptr)), "0"(old) + : "memory"); + return prev; + case 2: + __asm__ __volatile__(LOCK "cmpxchgw %w1,%2" + : "=a"(prev) + : "q"(new), "m"(*__xg(ptr)), "0"(old) + : "memory"); + return prev; + case 4: + __asm__ __volatile__(LOCK "cmpxchgl %1,%2" + : "=a"(prev) + : "q"(new), "m"(*__xg(ptr)), "0"(old) + : "memory"); + return prev; + } + return old; +} + +#define cmpxchg(ptr,o,n)\ + ((__typeof__(*(ptr)))__cmpxchg((ptr),(unsigned long)(o),\ + (unsigned long)(n),sizeof(*(ptr)))) + +#ifdef __KERNEL__ +struct alt_instr { + __u8 *instr; /* original instruction */ + __u8 *replacement; + __u8 cpuid; /* cpuid bit set for replacement */ + __u8 instrlen; /* length of original instruction */ + __u8 replacementlen; /* length of new instruction, <= instrlen */ + __u8 pad; +}; +#endif + +/* + * Alternative instructions for different CPU types or capabilities. + * + * This allows to use optimized instructions even on generic binary + * kernels. + * + * length of oldinstr must be longer or equal the length of newinstr + * It can be padded with nops as needed. + * + * For non barrier like inlines please define new variants + * without volatile and memory clobber. + */ +#define alternative(oldinstr, newinstr, feature) \ + asm volatile ("661:\n\t" oldinstr "\n662:\n" \ + ".section .altinstructions,\"a\"\n" \ + " .align 4\n" \ + " .long 661b\n" /* label */ \ + " .long 663f\n" /* new instruction */ \ + " .byte %c0\n" /* feature bit */ \ + " .byte 662b-661b\n" /* sourcelen */ \ + " .byte 664f-663f\n" /* replacementlen */ \ + ".previous\n" \ + ".section .altinstr_replacement,\"ax\"\n" \ + "663:\n\t" newinstr "\n664:\n" /* replacement */ \ + ".previous" :: "i" (feature) : "memory") + +/* + * Alternative inline assembly with input. + * + * Pecularities: + * No memory clobber here. + * Argument numbers start with 1. + * Best is to use constraints that are fixed size (like (%1) ... "r") + * If you use variable sized constraints like "m" or "g" in the + * replacement maake sure to pad to the worst case length. + */ +#define alternative_input(oldinstr, newinstr, feature, input...) \ + asm volatile ("661:\n\t" oldinstr "\n662:\n" \ + ".section .altinstructions,\"a\"\n" \ + " .align 4\n" \ + " .long 661b\n" /* label */ \ + " .long 663f\n" /* new instruction */ \ + " .byte %c0\n" /* feature bit */ \ + " .byte 662b-661b\n" /* sourcelen */ \ + " .byte 664f-663f\n" /* replacementlen */ \ + ".previous\n" \ + ".section .altinstr_replacement,\"ax\"\n" \ + "663:\n\t" newinstr "\n664:\n" /* replacement */ \ + ".previous" :: "i" (feature), ##input) + +/* + * Force strict CPU ordering. + * And yes, this is required on UP too when we're talking + * to devices. + * + * For now, "wmb()" doesn't actually do anything, as all + * Intel CPU's follow what Intel calls a *Processor Order*, + * in which all writes are seen in the program order even + * outside the CPU. + * + * I expect future Intel CPU's to have a weaker ordering, + * but I'd also expect them to finally get their act together + * and add some real memory barriers if so. + * + * Some non intel clones support out of order store. wmb() ceases to be a + * nop for these. + */ + + +/* + * Actually only lfence would be needed for mb() because all stores done + * by the kernel should be already ordered. But keep a full barrier for now. + */ + +#define mb() alternative("lock; addl $0,0(%%esp)", "mfence", X86_FEATURE_XMM2) +#define rmb() alternative("lock; addl $0,0(%%esp)", "lfence", X86_FEATURE_XMM2) + +/** + * read_barrier_depends - Flush all pending reads that subsequents reads + * depend on. + * + * No data-dependent reads from memory-like regions are ever reordered + * over this barrier. All reads preceding this primitive are guaranteed + * to access memory (but not necessarily other CPUs' caches) before any + * reads following this primitive that depend on the data return by + * any of the preceding reads. This primitive is much lighter weight than + * rmb() on most CPUs, and is never heavier weight than is + * rmb(). + * + * These ordering constraints are respected by both the local CPU + * and the compiler. + * + * Ordering is not guaranteed by anything other than these primitives, + * not even by data dependencies. See the documentation for + * memory_barrier() for examples and URLs to more information. + * + * For example, the following code would force ordering (the initial + * value of "a" is zero, "b" is one, and "p" is "&a"): + * + * <programlisting> + * CPU 0 CPU 1 + * + * b = 2; + * memory_barrier(); + * p = &b; q = p; + * read_barrier_depends(); + * d = *q; + * </programlisting> + * + * because the read of "*q" depends on the read of "p" and these + * two reads are separated by a read_barrier_depends(). However, + * the following code, with the same initial values for "a" and "b": + * + * <programlisting> + * CPU 0 CPU 1 + * + * a = 2; + * memory_barrier(); + * b = 3; y = b; + * read_barrier_depends(); + * x = a; + * </programlisting> + * + * does not enforce ordering, since there is no data dependency between + * the read of "a" and the read of "b". Therefore, on some CPUs, such + * as Alpha, "y" could be set to 3 and "x" to 0. Use rmb() + * in cases like thiswhere there are no data dependencies. + **/ + +#define read_barrier_depends() do { } while(0) + +#ifdef CONFIG_X86_OOSTORE +/* Actually there are no OOO store capable CPUs for now that do SSE, + but make it already an possibility. */ +#define wmb() alternative("lock; addl $0,0(%%esp)", "sfence", X86_FEATURE_XMM) +#else +#define wmb() __asm__ __volatile__ ("": : :"memory") +#endif + +#ifdef CONFIG_SMP +#define smp_wmb() wmb() +#if defined(CONFIG_SMP_ALTERNATIVES) && !defined(MODULE) +#define smp_alt_mb(instr) \ +__asm__ __volatile__("6667:\nnop\nnop\nnop\nnop\nnop\nnop\n6668:\n" \ + ".section __smp_alternatives,\"a\"\n" \ + ".long 6667b\n" \ + ".long 6673f\n" \ + ".previous\n" \ + ".section __smp_replacements,\"a\"\n" \ + "6673:.byte 6668b-6667b\n" \ + ".byte 6670f-6669f\n" \ + ".byte 6671f-6670f\n" \ + ".byte 0\n" \ + ".byte %c0\n" \ + "6669:lock;addl $0,0(%%esp)\n" \ + "6670:" instr "\n" \ + "6671:\n" \ + ".previous\n" \ + : \ + : "i" (X86_FEATURE_XMM2) \ + : "memory") +#define smp_rmb() smp_alt_mb("lfence") +#define smp_mb() smp_alt_mb("mfence") +#define set_mb(var, value) do { \ +unsigned long __set_mb_temp; \ +__asm__ __volatile__("6667:movl %1, %0\n6668:\n" \ + ".section __smp_alternatives,\"a\"\n" \ + ".long 6667b\n" \ + ".long 6673f\n" \ + ".previous\n" \ + ".section __smp_replacements,\"a\"\n" \ + "6673: .byte 6668b-6667b\n" \ + ".byte 6670f-6669f\n" \ + ".byte 0\n" \ + ".byte 6671f-6670f\n" \ + ".byte -1\n" \ + "6669: xchg %1, %0\n" \ + "6670:movl %1, %0\n" \ + "6671:\n" \ + ".previous\n" \ + : "=m" (var), "=r" (__set_mb_temp) \ + : "1" (value) \ + : "memory"); } while (0) +#else +#define smp_rmb() rmb() +#define smp_mb() mb() +#define set_mb(var, value) do { xchg(&var, value); } while (0) +#endif +#define smp_read_barrier_depends() read_barrier_depends() +#else +#define smp_mb() barrier() +#define smp_rmb() barrier() +#define smp_wmb() barrier() +#define smp_read_barrier_depends() do { } while(0) +#define set_mb(var, value) do { var = value; barrier(); } while (0) +#endif + +#define set_wmb(var, value) do { var = value; wmb(); } while (0) + +/* interrupt control.. */ +#define local_save_flags(x) do { typecheck(unsigned long,x); __asm__ __volatile__("pushfl ; popl %0":"=g" (x): /* no input */); } while (0) +#define local_irq_restore(x) do { typecheck(unsigned long,x); __asm__ __volatile__("pushl %0 ; popfl": /* no output */ :"g" (x):"memory", "cc"); } while (0) +#define local_irq_disable() __asm__ __volatile__("cli": : :"memory") +#define local_irq_enable() __asm__ __volatile__("sti": : :"memory") +/* used in the idle loop; sti takes one instruction cycle to complete */ +#define safe_halt() __asm__ __volatile__("sti; hlt": : :"memory") + +#define irqs_disabled() \ +({ \ + unsigned long flags; \ + local_save_flags(flags); \ + !(flags & (1<<9)); \ +}) + +/* For spinlocks etc */ +#define local_irq_save(x) __asm__ __volatile__("pushfl ; popl %0 ; cli":"=g" (x): /* no input */ :"memory") + +/* + * disable hlt during certain critical i/o operations + */ +#define HAVE_DISABLE_HLT +void disable_hlt(void); +void enable_hlt(void); + +extern int es7000_plat; +void cpu_idle_wait(void); + +extern unsigned long arch_align_stack(unsigned long sp); + +#endif --- linux-2.6.12-xen0/include/asm-i386/mach-xen/mach_system.h 1969-12-31 16:00:00.000000000 -0800 +++ linux-2.6.12-xen0-arch/include/asm-i386/mach-xen/mach_system.h 2005-08-03 01:36:51.000000000 -0700 @@ -0,0 +1,580 @@ +#ifndef __ASM_MACH_SYSTEM_H +#define __ASM_MACH_SYSTEM_H + +#include <linux/config.h> +#include <linux/kernel.h> +#include <linux/bitops.h> +#include <asm/segment.h> +#include <asm/cpufeature.h> +#include <asm/smp_alt.h> +#include <xen_synch_bitops.h> +#include <xen_hypervisor.h> + +#ifdef __KERNEL__ + +struct task_struct; /* one of the stranger aspects of C forward declarations.. */ +extern struct task_struct * FASTCALL(__switch_to(struct task_struct *prev, struct task_struct *next)); + +#define switch_to(prev,next,last) do { \ + unsigned long esi,edi; \ + asm volatile("pushfl\n\t" \ + "pushl %%ebp\n\t" \ + "movl %%esp,%0\n\t" /* save ESP */ \ + "movl %5,%%esp\n\t" /* restore ESP */ \ + "movl $1f,%1\n\t" /* save EIP */ \ + "pushl %6\n\t" /* restore EIP */ \ + "jmp __switch_to\n" \ + "1:\t" \ + "popl %%ebp\n\t" \ + "popfl" \ + :"=m" (prev->thread.esp),"=m" (prev->thread.eip), \ + "=a" (last),"=S" (esi),"=D" (edi) \ + :"m" (next->thread.esp),"m" (next->thread.eip), \ + "2" (prev), "d" (next)); \ +} while (0) + +#define _set_base(addr,base) do { unsigned long __pr; \ +__asm__ __volatile__ ("movw %%dx,%1\n\t" \ + "rorl $16,%%edx\n\t" \ + "movb %%dl,%2\n\t" \ + "movb %%dh,%3" \ + :"=&d" (__pr) \ + :"m" (*((addr)+2)), \ + "m" (*((addr)+4)), \ + "m" (*((addr)+7)), \ + "0" (base) \ + ); } while(0) + +#define _set_limit(addr,limit) do { unsigned long __lr; \ +__asm__ __volatile__ ("movw %%dx,%1\n\t" \ + "rorl $16,%%edx\n\t" \ + "movb %2,%%dh\n\t" \ + "andb $0xf0,%%dh\n\t" \ + "orb %%dh,%%dl\n\t" \ + "movb %%dl,%2" \ + :"=&d" (__lr) \ + :"m" (*(addr)), \ + "m" (*((addr)+6)), \ + "0" (limit) \ + ); } while(0) + +#define set_base(ldt,base) _set_base( ((char *)&(ldt)) , (base) ) +#define set_limit(ldt,limit) _set_limit( ((char *)&(ldt)) , ((limit)-1)>>12 ) + +static inline unsigned long _get_base(char * addr) +{ + unsigned long __base; + __asm__("movb %3,%%dh\n\t" + "movb %2,%%dl\n\t" + "shll $16,%%edx\n\t" + "movw %1,%%dx" + :"=&d" (__base) + :"m" (*((addr)+2)), + "m" (*((addr)+4)), + "m" (*((addr)+7))); + return __base; +} + +#define get_base(ldt) _get_base( ((char *)&(ldt)) ) + +#define _set_gate(gate_addr,type,dpl,addr,seg) do { } while(0) +/* + * Load a segment. Fall back on loading the zero + * segment if something goes wrong.. + */ +#define loadsegment(seg,value) \ + asm volatile("\n" \ + "1:\t" \ + "mov %0,%%" #seg "\n" \ + "2:\n" \ + ".section .fixup,\"ax\"\n" \ + "3:\t" \ + "pushl $0\n\t" \ + "popl %%" #seg "\n\t" \ + "jmp 2b\n" \ + ".previous\n" \ + ".section __ex_table,\"a\"\n\t" \ + ".align 4\n\t" \ + ".long 1b,3b\n" \ + ".previous" \ + : :"m" (value)) + +/* + * Save a segment register away + */ +#define savesegment(seg, value) \ + asm volatile("mov %%" #seg ",%0":"=m" (value)) + +/* + * Clear and set 'TS' bit respectively + */ +#define clts() (HYPERVISOR_fpu_taskswitch(0)) +#define read_cr0() ({ \ + unsigned int __dummy; \ + __asm__( \ + "movl %%cr0,%0\n\t" \ + :"=r" (__dummy)); \ + __dummy; \ +}) +#define write_cr0(x) \ + __asm__("movl %0,%%cr0": :"r" (x)); + +#define read_cr4() ({ \ + unsigned int __dummy; \ + __asm__( \ + "movl %%cr4,%0\n\t" \ + :"=r" (__dummy)); \ + __dummy; \ +}) +#define write_cr4(x) \ + __asm__("movl %0,%%cr4": :"r" (x)); +#define stts() (HYPERVISOR_fpu_taskswitch(1)) + +#endif /* __KERNEL__ */ + +#define wbinvd() \ + __asm__ __volatile__ ("wbinvd": : :"memory"); + +static inline unsigned long get_limit(unsigned long segment) +{ + unsigned long __limit; + __asm__("lsll %1,%0" + :"=r" (__limit):"r" (segment)); + return __limit+1; +} + +#define nop() __asm__ __volatile__ ("nop") + +#define xchg(ptr,v) ((__typeof__(*(ptr)))__xchg((unsigned long)(v),(ptr),sizeof(*(ptr)))) + +#define tas(ptr) (xchg((ptr),1)) + +struct __xchg_dummy { unsigned long a[100]; }; +#define __xg(x) ((struct __xchg_dummy *)(x)) + + +/* + * The semantics of XCHGCMP8B are a bit strange, this is why + * there is a loop and the loading of %%eax and %%edx has to + * be inside. This inlines well in most cases, the cached + * cost is around ~38 cycles. (in the future we might want + * to do an SIMD/3DNOW!/MMX/FPU 64-bit store here, but that + * might have an implicit FPU-save as a cost, so it's not + * clear which path to go.) + * + * cmpxchg8b must be used with the lock prefix here to allow + * the instruction to be executed atomically, see page 3-102 + * of the instruction set reference 24319102.pdf. We need + * the reader side to see the coherent 64bit value. + */ +static inline void __set_64bit (unsigned long long * ptr, + unsigned int low, unsigned int high) +{ + __asm__ __volatile__ ( + "\n1:\t" + "movl (%0), %%eax\n\t" + "movl 4(%0), %%edx\n\t" + "lock cmpxchg8b (%0)\n\t" + "jnz 1b" + : /* no outputs */ + : "D"(ptr), + "b"(low), + "c"(high) + : "ax","dx","memory"); +} + +static inline void __set_64bit_constant (unsigned long long *ptr, + unsigned long long value) +{ + __set_64bit(ptr,(unsigned int)(value), (unsigned int)((value)>>32ULL)); +} +#define ll_low(x) *(((unsigned int*)&(x))+0) +#define ll_high(x) *(((unsigned int*)&(x))+1) + +static inline void __set_64bit_var (unsigned long long *ptr, + unsigned long long value) +{ + __set_64bit(ptr,ll_low(value), ll_high(value)); +} + +#define set_64bit(ptr,value) \ +(__builtin_constant_p(value) ? \ + __set_64bit_constant(ptr, value) : \ + __set_64bit_var(ptr, value) ) + +#define _set_64bit(ptr,value) \ +(__builtin_constant_p(value) ? \ + __set_64bit(ptr, (unsigned int)(value), (unsigned int)((value)>>32ULL) ) : \ + __set_64bit(ptr, ll_low(value), ll_high(value)) ) + +/* + * Note: no "lock" prefix even on SMP: xchg always implies lock anyway + * Note 2: xchg has side effect, so that attribute volatile is necessary, + * but generally the primitive is invalid, *ptr is output argument. --ANK + */ +static inline unsigned long __xchg(unsigned long x, volatile void * ptr, int size) +{ + switch (size) { + case 1: + __asm__ __volatile__("xchgb %b0,%1" + :"=q" (x) + :"m" (*__xg(ptr)), "0" (x) + :"memory"); + break; + case 2: + __asm__ __volatile__("xchgw %w0,%1" + :"=r" (x) + :"m" (*__xg(ptr)), "0" (x) + :"memory"); + break; + case 4: + __asm__ __volatile__("xchgl %0,%1" + :"=r" (x) + :"m" (*__xg(ptr)), "0" (x) + :"memory"); + break; + } + return x; +} + +/* + * Atomic compare and exchange. Compare OLD with MEM, if identical, + * store NEW in MEM. Return the initial value in MEM. Success is + * indicated by comparing RETURN with OLD. + */ + +#ifdef CONFIG_X86_CMPXCHG +#define __HAVE_ARCH_CMPXCHG 1 +#endif + +static inline unsigned long __cmpxchg(volatile void *ptr, unsigned long old, + unsigned long new, int size) +{ + unsigned long prev; + switch (size) { + case 1: + __asm__ __volatile__(LOCK "cmpxchgb %b1,%2" + : "=a"(prev) + : "q"(new), "m"(*__xg(ptr)), "0"(old) + : "memory"); + return prev; + case 2: + __asm__ __volatile__(LOCK "cmpxchgw %w1,%2" + : "=a"(prev) + : "q"(new), "m"(*__xg(ptr)), "0"(old) + : "memory"); + return prev; + case 4: + __asm__ __volatile__(LOCK "cmpxchgl %1,%2" + : "=a"(prev) + : "q"(new), "m"(*__xg(ptr)), "0"(old) + : "memory"); + return prev; + } + return old; +} + +#define cmpxchg(ptr,o,n)\ + ((__typeof__(*(ptr)))__cmpxchg((ptr),(unsigned long)(o),\ + (unsigned long)(n),sizeof(*(ptr)))) + +#ifdef __KERNEL__ +struct alt_instr { + __u8 *instr; /* original instruction */ + __u8 *replacement; + __u8 cpuid; /* cpuid bit set for replacement */ + __u8 instrlen; /* length of original instruction */ + __u8 replacementlen; /* length of new instruction, <= instrlen */ + __u8 pad; +}; +#endif + +/* + * Alternative instructions for different CPU types or capabilities. + * + * This allows to use optimized instructions even on generic binary + * kernels. + * + * length of oldinstr must be longer or equal the length of newinstr + * It can be padded with nops as needed. + * + * For non barrier like inlines please define new variants + * without volatile and memory clobber. + */ +#define alternative(oldinstr, newinstr, feature) \ + asm volatile ("661:\n\t" oldinstr "\n662:\n" \ + ".section .altinstructions,\"a\"\n" \ + " .align 4\n" \ + " .long 661b\n" /* label */ \ + " .long 663f\n" /* new instruction */ \ + " .byte %c0\n" /* feature bit */ \ + " .byte 662b-661b\n" /* sourcelen */ \ + " .byte 664f-663f\n" /* replacementlen */ \ + ".previous\n" \ + ".section .altinstr_replacement,\"ax\"\n" \ + "663:\n\t" newinstr "\n664:\n" /* replacement */ \ + ".previous" :: "i" (feature) : "memory") + +/* + * Alternative inline assembly with input. + * + * Pecularities: + * No memory clobber here. + * Argument numbers start with 1. + * Best is to use constraints that are fixed size (like (%1) ... "r") + * If you use variable sized constraints like "m" or "g" in the + * replacement maake sure to pad to the worst case length. + */ +#define alternative_input(oldinstr, newinstr, feature, input...) \ + asm volatile ("661:\n\t" oldinstr "\n662:\n" \ + ".section .altinstructions,\"a\"\n" \ + " .align 4\n" \ + " .long 661b\n" /* label */ \ + " .long 663f\n" /* new instruction */ \ + " .byte %c0\n" /* feature bit */ \ + " .byte 662b-661b\n" /* sourcelen */ \ + " .byte 664f-663f\n" /* replacementlen */ \ + ".previous\n" \ + ".section .altinstr_replacement,\"ax\"\n" \ + "663:\n\t" newinstr "\n664:\n" /* replacement */ \ + ".previous" :: "i" (feature), ##input) + +/* + * Force strict CPU ordering. + * And yes, this is required on UP too when we're talking + * to devices. + * + * For now, "wmb()" doesn't actually do anything, as all + * Intel CPU's follow what Intel calls a *Processor Order*, + * in which all writes are seen in the program order even + * outside the CPU. + * + * I expect future Intel CPU's to have a weaker ordering, + * but I'd also expect them to finally get their act together + * and add some real memory barriers if so. + * + * Some non intel clones support out of order store. wmb() ceases to be a + * nop for these. + */ + + +/* + * Actually only lfence would be needed for mb() because all stores done + * by the kernel should be already ordered. But keep a full barrier for now. + */ + +#define mb() alternative("lock; addl $0,0(%%esp)", "mfence", X86_FEATURE_XMM2) +#define rmb() alternative("lock; addl $0,0(%%esp)", "lfence", X86_FEATURE_XMM2) + +/** + * read_barrier_depends - Flush all pending reads that subsequents reads + * depend on. + * + * No data-dependent reads from memory-like regions are ever reordered + * over this barrier. All reads preceding this primitive are guaranteed + * to access memory (but not necessarily other CPUs' caches) before any + * reads following this primitive that depend on the data return by + * any of the preceding reads. This primitive is much lighter weight than + * rmb() on most CPUs, and is never heavier weight than is + * rmb(). + * + * These ordering constraints are respected by both the local CPU + * and the compiler. + * + * Ordering is not guaranteed by anything other than these primitives, + * not even by data dependencies. See the documentation for + * memory_barrier() for examples and URLs to more information. + * + * For example, the following code would force ordering (the initial + * value of "a" is zero, "b" is one, and "p" is "&a"): + * + * <programlisting> + * CPU 0 CPU 1 + * + * b = 2; + * memory_barrier(); + * p = &b; q = p; + * read_barrier_depends(); + * d = *q; + * </programlisting> + * + * because the read of "*q" depends on the read of "p" and these + * two reads are separated by a read_barrier_depends(). However, + * the following code, with the same initial values for "a" and "b": + * + * <programlisting> + * CPU 0 CPU 1 + * + * a = 2; + * memory_barrier(); + * b = 3; y = b; + * read_barrier_depends(); + * x = a; + * </programlisting> + * + * does not enforce ordering, since there is no data dependency between + * the read of "a" and the read of "b". Therefore, on some CPUs, such + * as Alpha, "y" could be set to 3 and "x" to 0. Use rmb() + * in cases like thiswhere there are no data dependencies. + **/ + +#define read_barrier_depends() do { } while(0) + +#ifdef CONFIG_X86_OOSTORE +/* Actually there are no OOO store capable CPUs for now that do SSE, + but make it already an possibility. */ +#define wmb() alternative("lock; addl $0,0(%%esp)", "sfence", X86_FEATURE_XMM) +#else +#define wmb() __asm__ __volatile__ ("": : :"memory") +#endif + +#ifdef CONFIG_SMP +#define smp_wmb() wmb() +#if defined(CONFIG_SMP_ALTERNATIVES) && !defined(MODULE) +#define smp_alt_mb(instr) \ +__asm__ __volatile__("6667:\nnop\nnop\nnop\nnop\nnop\nnop\n6668:\n" \ + ".section __smp_alternatives,\"a\"\n" \ + ".long 6667b\n" \ + ".long 6673f\n" \ + ".previous\n" \ + ".section __smp_replacements,\"a\"\n" \ + "6673:.byte 6668b-6667b\n" \ + ".byte 6670f-6669f\n" \ + ".byte 6671f-6670f\n" \ + ".byte 0\n" \ + ".byte %c0\n" \ + "6669:lock;addl $0,0(%%esp)\n" \ + "6670:" instr "\n" \ + "6671:\n" \ + ".previous\n" \ + : \ + : "i" (X86_FEATURE_XMM2) \ + : "memory") +#define smp_rmb() smp_alt_mb("lfence") +#define smp_mb() smp_alt_mb("mfence") +#define set_mb(var, value) do { \ +unsigned long __set_mb_temp; \ +__asm__ __volatile__("6667:movl %1, %0\n6668:\n" \ + ".section __smp_alternatives,\"a\"\n" \ + ".long 6667b\n" \ + ".long 6673f\n" \ + ".previous\n" \ + ".section __smp_replacements,\"a\"\n" \ + "6673: .byte 6668b-6667b\n" \ + ".byte 6670f-6669f\n" \ + ".byte 0\n" \ + ".byte 6671f-6670f\n" \ + ".byte -1\n" \ + "6669: xchg %1, %0\n" \ + "6670:movl %1, %0\n" \ + "6671:\n" \ + ".previous\n" \ + : "=m" (var), "=r" (__set_mb_temp) \ + : "1" (value) \ + : "memory"); } while (0) +#else +#define smp_rmb() rmb() +#define smp_mb() mb() +#define set_mb(var, value) do { xchg(&var, value); } while (0) +#endif +#define smp_read_barrier_depends() read_barrier_depends() +#else +#define smp_mb() barrier() +#define smp_rmb() barrier() +#define smp_wmb() barrier() +#define smp_read_barrier_depends() do { } while(0) +#define set_mb(var, value) do { var = value; barrier(); } while (0) +#endif + +#define set_wmb(var, value) do { var = value; wmb(); } while (0) + +/* interrupt control.. */ + +/* + * The use of 'barrier' in the following reflects their use as local-lock + * operations. Reentrancy must be prevented (e.g., __cli()) /before/ following + * critical operations are executed. All critical operations must complete + * /before/ reentrancy is permitted (e.g., __sti()). Alpha architecture also + * includes these barriers, for example. + */ + +#define __cli() \ +do { \ + vcpu_info_t *_vcpu; \ + preempt_disable(); \ + _vcpu = &HYPERVISOR_shared_info->vcpu_data[smp_processor_id()]; \ + _vcpu->evtchn_upcall_mask = 1; \ + preempt_enable_no_resched(); \ + barrier(); \ +} while (0) + +#define __sti() \ +do { \ + vcpu_info_t *_vcpu; \ + barrier(); \ + preempt_disable(); \ + _vcpu = &HYPERVISOR_shared_info->vcpu_data[smp_processor_id()]; \ + _vcpu->evtchn_upcall_mask = 0; \ + barrier(); /* unmask then check (avoid races) */ \ + if ( unlikely(_vcpu->evtchn_upcall_pending) ) \ + force_evtchn_callback(); \ + preempt_enable(); \ +} while (0) + +#define __save_flags(x) \ +do { \ + vcpu_info_t *_vcpu; \ + _vcpu = &HYPERVISOR_shared_info->vcpu_data[smp_processor_id()]; \ + (x) = _vcpu->evtchn_upcall_mask; \ +} while (0) + +#define __restore_flags(x) \ +do { \ + vcpu_info_t *_vcpu; \ + barrier(); \ + preempt_disable(); \ + _vcpu = &HYPERVISOR_shared_info->vcpu_data[smp_processor_id()]; \ + if ((_vcpu->evtchn_upcall_mask = (x)) == 0) { \ + barrier(); /* unmask then check (avoid races) */ \ + if ( unlikely(_vcpu->evtchn_upcall_pending) ) \ + force_evtchn_callback(); \ + preempt_enable(); \ + } else \ + preempt_enable_no_resched(); \ +} while (0) + +#define safe_halt() ((void)0) + +#define __save_and_cli(x) \ +do { \ + vcpu_info_t *_vcpu; \ + preempt_disable(); \ + _vcpu = &HYPERVISOR_shared_info->vcpu_data[smp_processor_id()]; \ + (x) = _vcpu->evtchn_upcall_mask; \ + _vcpu->evtchn_upcall_mask = 1; \ + preempt_enable_no_resched(); \ + barrier(); \ +} while (0) + +#define local_irq_save(x) __save_and_cli(x) +#define local_irq_restore(x) __restore_flags(x) +#define local_save_flags(x) __save_flags(x) +#define local_irq_disable() __cli() +#define local_irq_enable() __sti() + +#define irqs_disabled() \ + HYPERVISOR_shared_info->vcpu_data[smp_processor_id()].evtchn_upcall_mask + +/* + * disable hlt during certain critical i/o operations + */ +#define HAVE_DISABLE_HLT +void disable_hlt(void); +void enable_hlt(void); + +extern int es7000_plat; +void cpu_idle_wait(void); + +extern unsigned long arch_align_stack(unsigned long sp); + +#endif -- _______________________________________________ Xen-merge mailing list Xen-merge@xxxxxxxxxxxxxxxxxxx http://lists.xensource.com/xen-merge
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