1 #ifndef _ASM_X86_PROCESSOR_H
2 #define _ASM_X86_PROCESSOR_H
4 #include <asm/processor-flags.h>
6 /* Forward declaration, a strange C thing */
11 #include <asm/math_emu.h>
12 #include <asm/segment.h>
13 #include <asm/types.h>
14 #include <asm/sigcontext.h>
15 #include <asm/current.h>
16 #include <asm/cpufeature.h>
17 #include <asm/system.h>
19 #include <asm/pgtable_types.h>
20 #include <asm/percpu.h>
22 #include <asm/desc_defs.h>
26 #include <linux/personality.h>
27 #include <linux/cpumask.h>
28 #include <linux/cache.h>
29 #include <linux/threads.h>
30 #include <linux/init.h>
33 * Default implementation of macro that returns current
34 * instruction pointer ("program counter").
36 static inline void *current_text_addr(void)
40 asm volatile("mov $1f, %0; 1:":"=r" (pc));
45 #ifdef CONFIG_X86_VSMP
46 # define ARCH_MIN_TASKALIGN (1 << INTERNODE_CACHE_SHIFT)
47 # define ARCH_MIN_MMSTRUCT_ALIGN (1 << INTERNODE_CACHE_SHIFT)
49 # define ARCH_MIN_TASKALIGN 16
50 # define ARCH_MIN_MMSTRUCT_ALIGN 0
54 * CPU type and hardware bug flags. Kept separately for each CPU.
55 * Members of this structure are referenced in head.S, so think twice
56 * before touching them. [mj]
60 __u8 x86; /* CPU family */
61 __u8 x86_vendor; /* CPU vendor */
65 char wp_works_ok; /* It doesn't on 386's */
67 /* Problems on some 486Dx4's and old 386's: */
76 /* Number of 4K pages in DTLB/ITLB combined(in pages): */
81 /* CPUID returned core id bits: */
83 /* Max extended CPUID function supported: */
84 __u32 extended_cpuid_level;
85 /* Maximum supported CPUID level, -1=no CPUID: */
87 __u32 x86_capability[NCAPINTS];
88 char x86_vendor_id[16];
89 char x86_model_id[64];
90 /* in KB - valid for CPUS which support this call: */
92 int x86_cache_alignment; /* In bytes */
94 unsigned long loops_per_jiffy;
96 /* cpus sharing the last level cache: */
97 cpumask_var_t llc_shared_map;
99 /* cpuid returned max cores value: */
103 u16 x86_clflush_size;
105 /* number of cores as seen by the OS: */
107 /* Physical processor id: */
111 /* Index into per_cpu list: */
114 unsigned int x86_hyper_vendor;
115 } __attribute__((__aligned__(SMP_CACHE_BYTES)));
117 #define X86_VENDOR_INTEL 0
118 #define X86_VENDOR_CYRIX 1
119 #define X86_VENDOR_AMD 2
120 #define X86_VENDOR_UMC 3
121 #define X86_VENDOR_CENTAUR 5
122 #define X86_VENDOR_TRANSMETA 7
123 #define X86_VENDOR_NSC 8
124 #define X86_VENDOR_NUM 9
126 #define X86_VENDOR_UNKNOWN 0xff
128 #define X86_HYPER_VENDOR_NONE 0
129 #define X86_HYPER_VENDOR_VMWARE 1
132 * capabilities of CPUs
134 extern struct cpuinfo_x86 boot_cpu_data;
135 extern struct cpuinfo_x86 new_cpu_data;
137 extern struct tss_struct doublefault_tss;
138 extern __u32 cpu_caps_cleared[NCAPINTS];
139 extern __u32 cpu_caps_set[NCAPINTS];
142 DECLARE_PER_CPU_SHARED_ALIGNED(struct cpuinfo_x86, cpu_info);
143 #define cpu_data(cpu) per_cpu(cpu_info, cpu)
144 #define current_cpu_data __get_cpu_var(cpu_info)
146 #define cpu_data(cpu) boot_cpu_data
147 #define current_cpu_data boot_cpu_data
150 extern const struct seq_operations cpuinfo_op;
152 static inline int hlt_works(int cpu)
155 return cpu_data(cpu).hlt_works_ok;
161 #define cache_line_size() (boot_cpu_data.x86_cache_alignment)
163 extern void cpu_detect(struct cpuinfo_x86 *c);
165 extern struct pt_regs *idle_regs(struct pt_regs *);
167 extern void early_cpu_init(void);
168 extern void identify_boot_cpu(void);
169 extern void identify_secondary_cpu(struct cpuinfo_x86 *);
170 extern void print_cpu_info(struct cpuinfo_x86 *);
171 extern void init_scattered_cpuid_features(struct cpuinfo_x86 *c);
172 extern unsigned int init_intel_cacheinfo(struct cpuinfo_x86 *c);
173 extern unsigned short num_cache_leaves;
175 extern void detect_extended_topology(struct cpuinfo_x86 *c);
176 extern void detect_ht(struct cpuinfo_x86 *c);
178 static inline void native_cpuid(unsigned int *eax, unsigned int *ebx,
179 unsigned int *ecx, unsigned int *edx)
181 /* ecx is often an input as well as an output. */
187 : "0" (*eax), "2" (*ecx));
190 static inline void load_cr3(pgd_t *pgdir)
192 write_cr3(__pa(pgdir));
196 /* This is the TSS defined by the hardware. */
198 unsigned short back_link, __blh;
200 unsigned short ss0, __ss0h;
202 /* ss1 caches MSR_IA32_SYSENTER_CS: */
203 unsigned short ss1, __ss1h;
205 unsigned short ss2, __ss2h;
217 unsigned short es, __esh;
218 unsigned short cs, __csh;
219 unsigned short ss, __ssh;
220 unsigned short ds, __dsh;
221 unsigned short fs, __fsh;
222 unsigned short gs, __gsh;
223 unsigned short ldt, __ldth;
224 unsigned short trace;
225 unsigned short io_bitmap_base;
227 } __attribute__((packed));
241 } __attribute__((packed)) ____cacheline_aligned;
247 #define IO_BITMAP_BITS 65536
248 #define IO_BITMAP_BYTES (IO_BITMAP_BITS/8)
249 #define IO_BITMAP_LONGS (IO_BITMAP_BYTES/sizeof(long))
250 #define IO_BITMAP_OFFSET offsetof(struct tss_struct, io_bitmap)
251 #define INVALID_IO_BITMAP_OFFSET 0x8000
255 * The hardware state:
257 struct x86_hw_tss x86_tss;
260 * The extra 1 is there because the CPU will access an
261 * additional byte beyond the end of the IO permission
262 * bitmap. The extra byte must be all 1 bits, and must
263 * be within the limit.
265 unsigned long io_bitmap[IO_BITMAP_LONGS + 1];
268 * .. and then another 0x100 bytes for the emergency kernel stack:
270 unsigned long stack[64];
272 } ____cacheline_aligned;
274 DECLARE_PER_CPU_SHARED_ALIGNED(struct tss_struct, init_tss);
277 * Save the original ist values for checking stack pointers during debugging
280 unsigned long ist[7];
283 #define MXCSR_DEFAULT 0x1f80
285 struct i387_fsave_struct {
286 u32 cwd; /* FPU Control Word */
287 u32 swd; /* FPU Status Word */
288 u32 twd; /* FPU Tag Word */
289 u32 fip; /* FPU IP Offset */
290 u32 fcs; /* FPU IP Selector */
291 u32 foo; /* FPU Operand Pointer Offset */
292 u32 fos; /* FPU Operand Pointer Selector */
294 /* 8*10 bytes for each FP-reg = 80 bytes: */
297 /* Software status information [not touched by FSAVE ]: */
301 struct i387_fxsave_struct {
302 u16 cwd; /* Control Word */
303 u16 swd; /* Status Word */
304 u16 twd; /* Tag Word */
305 u16 fop; /* Last Instruction Opcode */
308 u64 rip; /* Instruction Pointer */
309 u64 rdp; /* Data Pointer */
312 u32 fip; /* FPU IP Offset */
313 u32 fcs; /* FPU IP Selector */
314 u32 foo; /* FPU Operand Offset */
315 u32 fos; /* FPU Operand Selector */
318 u32 mxcsr; /* MXCSR Register State */
319 u32 mxcsr_mask; /* MXCSR Mask */
321 /* 8*16 bytes for each FP-reg = 128 bytes: */
324 /* 16*16 bytes for each XMM-reg = 256 bytes: */
334 } __attribute__((aligned(16)));
336 struct i387_soft_struct {
344 /* 8*10 bytes for each FP-reg = 80 bytes: */
352 struct math_emu_info *info;
357 /* 16 * 16 bytes for each YMMH-reg = 256 bytes */
361 struct xsave_hdr_struct {
365 } __attribute__((packed));
367 struct xsave_struct {
368 struct i387_fxsave_struct i387;
369 struct xsave_hdr_struct xsave_hdr;
370 struct ymmh_struct ymmh;
371 /* new processor state extensions will go here */
372 } __attribute__ ((packed, aligned (64)));
374 union thread_xstate {
375 struct i387_fsave_struct fsave;
376 struct i387_fxsave_struct fxsave;
377 struct i387_soft_struct soft;
378 struct xsave_struct xsave;
382 DECLARE_PER_CPU(struct orig_ist, orig_ist);
384 union irq_stack_union {
385 char irq_stack[IRQ_STACK_SIZE];
387 * GCC hardcodes the stack canary as %gs:40. Since the
388 * irq_stack is the object at %gs:0, we reserve the bottom
389 * 48 bytes of the irq stack for the canary.
393 unsigned long stack_canary;
397 DECLARE_PER_CPU_FIRST(union irq_stack_union, irq_stack_union);
398 DECLARE_INIT_PER_CPU(irq_stack_union);
400 DECLARE_PER_CPU(char *, irq_stack_ptr);
401 DECLARE_PER_CPU(unsigned int, irq_count);
402 extern unsigned long kernel_eflags;
403 extern asmlinkage void ignore_sysret(void);
405 #ifdef CONFIG_CC_STACKPROTECTOR
406 DECLARE_PER_CPU(unsigned long, stack_canary);
410 extern unsigned int xstate_size;
411 extern void free_thread_xstate(struct task_struct *);
412 extern struct kmem_cache *task_xstate_cachep;
413 extern void init_scattered_cpuid_features(struct cpuinfo_x86 *c);
414 extern unsigned int init_intel_cacheinfo(struct cpuinfo_x86 *c);
415 extern unsigned short num_cache_leaves;
417 struct thread_struct {
418 /* Cached TLS descriptors: */
419 struct desc_struct tls_array[GDT_ENTRY_TLS_ENTRIES];
423 unsigned long sysenter_cs;
425 unsigned long usersp; /* Copy from PDA */
428 unsigned short fsindex;
429 unsigned short gsindex;
434 /* Hardware debugging registers: */
435 unsigned long debugreg0;
436 unsigned long debugreg1;
437 unsigned long debugreg2;
438 unsigned long debugreg3;
439 unsigned long debugreg6;
440 unsigned long debugreg7;
443 unsigned long trap_no;
444 unsigned long error_code;
445 /* floating point and extended processor state */
446 union thread_xstate *xstate;
448 /* Virtual 86 mode info */
449 struct vm86_struct __user *vm86_info;
450 unsigned long screen_bitmap;
451 unsigned long v86flags;
452 unsigned long v86mask;
453 unsigned long saved_sp0;
454 unsigned int saved_fs;
455 unsigned int saved_gs;
457 /* IO permissions: */
458 unsigned long *io_bitmap_ptr;
460 /* Max allowed port in the bitmap, in bytes: */
461 unsigned io_bitmap_max;
462 /* MSR_IA32_DEBUGCTLMSR value to switch in if TIF_DEBUGCTLMSR is set. */
463 unsigned long debugctlmsr;
465 /* Debug Store context; see include/asm-x86/ds.h; goes into MSR_IA32_DS_AREA */
466 struct ds_context *ds_ctx;
467 #endif /* CONFIG_X86_DS */
468 #ifdef CONFIG_X86_PTRACE_BTS
469 /* the signal to send on a bts buffer overflow */
470 unsigned int bts_ovfl_signal;
471 #endif /* CONFIG_X86_PTRACE_BTS */
474 static inline unsigned long native_get_debugreg(int regno)
476 unsigned long val = 0; /* Damn you, gcc! */
480 asm("mov %%db0, %0" :"=r" (val));
483 asm("mov %%db1, %0" :"=r" (val));
486 asm("mov %%db2, %0" :"=r" (val));
489 asm("mov %%db3, %0" :"=r" (val));
492 asm("mov %%db6, %0" :"=r" (val));
495 asm("mov %%db7, %0" :"=r" (val));
503 static inline void native_set_debugreg(int regno, unsigned long value)
507 asm("mov %0, %%db0" ::"r" (value));
510 asm("mov %0, %%db1" ::"r" (value));
513 asm("mov %0, %%db2" ::"r" (value));
516 asm("mov %0, %%db3" ::"r" (value));
519 asm("mov %0, %%db6" ::"r" (value));
522 asm("mov %0, %%db7" ::"r" (value));
530 * Set IOPL bits in EFLAGS from given mask
532 static inline void native_set_iopl_mask(unsigned mask)
537 asm volatile ("pushfl;"
544 : "i" (~X86_EFLAGS_IOPL), "r" (mask));
549 native_load_sp0(struct tss_struct *tss, struct thread_struct *thread)
551 tss->x86_tss.sp0 = thread->sp0;
553 /* Only happens when SEP is enabled, no need to test "SEP"arately: */
554 if (unlikely(tss->x86_tss.ss1 != thread->sysenter_cs)) {
555 tss->x86_tss.ss1 = thread->sysenter_cs;
556 wrmsr(MSR_IA32_SYSENTER_CS, thread->sysenter_cs, 0);
561 static inline void native_swapgs(void)
564 asm volatile("swapgs" ::: "memory");
568 #ifdef CONFIG_PARAVIRT
569 #include <asm/paravirt.h>
571 #define __cpuid native_cpuid
572 #define paravirt_enabled() 0
575 * These special macros can be used to get or set a debugging register
577 #define get_debugreg(var, register) \
578 (var) = native_get_debugreg(register)
579 #define set_debugreg(value, register) \
580 native_set_debugreg(register, value)
582 static inline void load_sp0(struct tss_struct *tss,
583 struct thread_struct *thread)
585 native_load_sp0(tss, thread);
588 #define set_iopl_mask native_set_iopl_mask
589 #endif /* CONFIG_PARAVIRT */
592 * Save the cr4 feature set we're using (ie
593 * Pentium 4MB enable and PPro Global page
594 * enable), so that any CPU's that boot up
595 * after us can get the correct flags.
597 extern unsigned long mmu_cr4_features;
599 static inline void set_in_cr4(unsigned long mask)
603 mmu_cr4_features |= mask;
609 static inline void clear_in_cr4(unsigned long mask)
613 mmu_cr4_features &= ~mask;
625 * create a kernel thread without removing it from tasklists
627 extern int kernel_thread(int (*fn)(void *), void *arg, unsigned long flags);
629 /* Free all resources held by a thread. */
630 extern void release_thread(struct task_struct *);
632 /* Prepare to copy thread state - unlazy all lazy state */
633 extern void prepare_to_copy(struct task_struct *tsk);
635 unsigned long get_wchan(struct task_struct *p);
638 * Generic CPUID function
639 * clear %ecx since some cpus (Cyrix MII) do not set or clear %ecx
640 * resulting in stale register contents being returned.
642 static inline void cpuid(unsigned int op,
643 unsigned int *eax, unsigned int *ebx,
644 unsigned int *ecx, unsigned int *edx)
648 __cpuid(eax, ebx, ecx, edx);
651 /* Some CPUID calls want 'count' to be placed in ecx */
652 static inline void cpuid_count(unsigned int op, int count,
653 unsigned int *eax, unsigned int *ebx,
654 unsigned int *ecx, unsigned int *edx)
658 __cpuid(eax, ebx, ecx, edx);
662 * CPUID functions returning a single datum
664 static inline unsigned int cpuid_eax(unsigned int op)
666 unsigned int eax, ebx, ecx, edx;
668 cpuid(op, &eax, &ebx, &ecx, &edx);
673 static inline unsigned int cpuid_ebx(unsigned int op)
675 unsigned int eax, ebx, ecx, edx;
677 cpuid(op, &eax, &ebx, &ecx, &edx);
682 static inline unsigned int cpuid_ecx(unsigned int op)
684 unsigned int eax, ebx, ecx, edx;
686 cpuid(op, &eax, &ebx, &ecx, &edx);
691 static inline unsigned int cpuid_edx(unsigned int op)
693 unsigned int eax, ebx, ecx, edx;
695 cpuid(op, &eax, &ebx, &ecx, &edx);
700 /* REP NOP (PAUSE) is a good thing to insert into busy-wait loops. */
701 static inline void rep_nop(void)
703 asm volatile("rep; nop" ::: "memory");
706 static inline void cpu_relax(void)
711 /* Stop speculative execution: */
712 static inline void sync_core(void)
716 asm volatile("cpuid" : "=a" (tmp) : "0" (1)
717 : "ebx", "ecx", "edx", "memory");
720 static inline void __monitor(const void *eax, unsigned long ecx,
723 /* "monitor %eax, %ecx, %edx;" */
724 asm volatile(".byte 0x0f, 0x01, 0xc8;"
725 :: "a" (eax), "c" (ecx), "d"(edx));
728 static inline void __mwait(unsigned long eax, unsigned long ecx)
730 /* "mwait %eax, %ecx;" */
731 asm volatile(".byte 0x0f, 0x01, 0xc9;"
732 :: "a" (eax), "c" (ecx));
735 static inline void __sti_mwait(unsigned long eax, unsigned long ecx)
738 /* "mwait %eax, %ecx;" */
739 asm volatile("sti; .byte 0x0f, 0x01, 0xc9;"
740 :: "a" (eax), "c" (ecx));
743 extern void mwait_idle_with_hints(unsigned long eax, unsigned long ecx);
745 extern void select_idle_routine(const struct cpuinfo_x86 *c);
746 extern void init_c1e_mask(void);
748 extern unsigned long boot_option_idle_override;
749 extern unsigned long idle_halt;
750 extern unsigned long idle_nomwait;
753 * on systems with caches, caches must be flashed as the absolute
754 * last instruction before going into a suspended halt. Otherwise,
755 * dirty data can linger in the cache and become stale on resume,
756 * leading to strange errors.
758 * perform a variety of operations to guarantee that the compiler
759 * will not reorder instructions. wbinvd itself is serializing
760 * so the processor will not reorder.
762 * Systems without cache can just go into halt.
764 static inline void wbinvd_halt(void)
767 /* check for clflush to determine if wbinvd is legal */
769 asm volatile("cli; wbinvd; 1: hlt; jmp 1b" : : : "memory");
775 extern void enable_sep_cpu(void);
776 extern int sysenter_setup(void);
778 /* Defined in head.S */
779 extern struct desc_ptr early_gdt_descr;
781 extern void cpu_set_gdt(int);
782 extern void switch_to_new_gdt(int);
783 extern void load_percpu_segment(int);
784 extern void cpu_init(void);
786 static inline unsigned long get_debugctlmsr(void)
788 unsigned long debugctlmsr = 0;
790 #ifndef CONFIG_X86_DEBUGCTLMSR
791 if (boot_cpu_data.x86 < 6)
794 rdmsrl(MSR_IA32_DEBUGCTLMSR, debugctlmsr);
799 static inline void update_debugctlmsr(unsigned long debugctlmsr)
801 #ifndef CONFIG_X86_DEBUGCTLMSR
802 if (boot_cpu_data.x86 < 6)
805 wrmsrl(MSR_IA32_DEBUGCTLMSR, debugctlmsr);
809 * from system description table in BIOS. Mostly for MCA use, but
810 * others may find it useful:
812 extern unsigned int machine_id;
813 extern unsigned int machine_submodel_id;
814 extern unsigned int BIOS_revision;
816 /* Boot loader type from the setup header: */
817 extern int bootloader_type;
818 extern int bootloader_version;
820 extern char ignore_fpu_irq;
822 #define HAVE_ARCH_PICK_MMAP_LAYOUT 1
823 #define ARCH_HAS_PREFETCHW
824 #define ARCH_HAS_SPINLOCK_PREFETCH
827 # define BASE_PREFETCH ASM_NOP4
828 # define ARCH_HAS_PREFETCH
830 # define BASE_PREFETCH "prefetcht0 (%1)"
834 * Prefetch instructions for Pentium III (+) and AMD Athlon (+)
836 * It's not worth to care about 3dnow prefetches for the K6
837 * because they are microcoded there and very slow.
839 static inline void prefetch(const void *x)
841 alternative_input(BASE_PREFETCH,
848 * 3dnow prefetch to get an exclusive cache line.
849 * Useful for spinlocks to avoid one state transition in the
850 * cache coherency protocol:
852 static inline void prefetchw(const void *x)
854 alternative_input(BASE_PREFETCH,
860 static inline void spin_lock_prefetch(const void *x)
867 * User space process size: 3GB (default).
869 #define TASK_SIZE PAGE_OFFSET
870 #define TASK_SIZE_MAX TASK_SIZE
871 #define STACK_TOP TASK_SIZE
872 #define STACK_TOP_MAX STACK_TOP
874 #define INIT_THREAD { \
875 .sp0 = sizeof(init_stack) + (long)&init_stack, \
877 .sysenter_cs = __KERNEL_CS, \
878 .io_bitmap_ptr = NULL, \
879 .fs = __KERNEL_PERCPU, \
883 * Note that the .io_bitmap member must be extra-big. This is because
884 * the CPU will access an additional byte beyond the end of the IO
885 * permission bitmap. The extra byte must be all 1 bits, and must
886 * be within the limit.
890 .sp0 = sizeof(init_stack) + (long)&init_stack, \
891 .ss0 = __KERNEL_DS, \
892 .ss1 = __KERNEL_CS, \
893 .io_bitmap_base = INVALID_IO_BITMAP_OFFSET, \
895 .io_bitmap = { [0 ... IO_BITMAP_LONGS] = ~0 }, \
898 extern unsigned long thread_saved_pc(struct task_struct *tsk);
900 #define THREAD_SIZE_LONGS (THREAD_SIZE/sizeof(unsigned long))
901 #define KSTK_TOP(info) \
903 unsigned long *__ptr = (unsigned long *)(info); \
904 (unsigned long)(&__ptr[THREAD_SIZE_LONGS]); \
908 * The below -8 is to reserve 8 bytes on top of the ring0 stack.
909 * This is necessary to guarantee that the entire "struct pt_regs"
910 * is accessable even if the CPU haven't stored the SS/ESP registers
911 * on the stack (interrupt gate does not save these registers
912 * when switching to the same priv ring).
913 * Therefore beware: accessing the ss/esp fields of the
914 * "struct pt_regs" is possible, but they may contain the
915 * completely wrong values.
917 #define task_pt_regs(task) \
919 struct pt_regs *__regs__; \
920 __regs__ = (struct pt_regs *)(KSTK_TOP(task_stack_page(task))-8); \
924 #define KSTK_ESP(task) (task_pt_regs(task)->sp)
928 * User space process size. 47bits minus one guard page.
930 #define TASK_SIZE_MAX ((1UL << 47) - PAGE_SIZE)
932 /* This decides where the kernel will search for a free chunk of vm
933 * space during mmap's.
935 #define IA32_PAGE_OFFSET ((current->personality & ADDR_LIMIT_3GB) ? \
936 0xc0000000 : 0xFFFFe000)
938 #define TASK_SIZE (test_thread_flag(TIF_IA32) ? \
939 IA32_PAGE_OFFSET : TASK_SIZE_MAX)
940 #define TASK_SIZE_OF(child) ((test_tsk_thread_flag(child, TIF_IA32)) ? \
941 IA32_PAGE_OFFSET : TASK_SIZE_MAX)
943 #define STACK_TOP TASK_SIZE
944 #define STACK_TOP_MAX TASK_SIZE_MAX
946 #define INIT_THREAD { \
947 .sp0 = (unsigned long)&init_stack + sizeof(init_stack) \
951 .x86_tss.sp0 = (unsigned long)&init_stack + sizeof(init_stack) \
955 * Return saved PC of a blocked thread.
956 * What is this good for? it will be always the scheduler or ret_from_fork.
958 #define thread_saved_pc(t) (*(unsigned long *)((t)->thread.sp - 8))
960 #define task_pt_regs(tsk) ((struct pt_regs *)(tsk)->thread.sp0 - 1)
961 #define KSTK_ESP(tsk) -1 /* sorry. doesn't work for syscall. */
962 #endif /* CONFIG_X86_64 */
964 extern void start_thread(struct pt_regs *regs, unsigned long new_ip,
965 unsigned long new_sp);
968 * This decides where the kernel will search for a free chunk of vm
969 * space during mmap's.
971 #define TASK_UNMAPPED_BASE (PAGE_ALIGN(TASK_SIZE / 3))
973 #define KSTK_EIP(task) (task_pt_regs(task)->ip)
975 /* Get/set a process' ability to use the timestamp counter instruction */
976 #define GET_TSC_CTL(adr) get_tsc_mode((adr))
977 #define SET_TSC_CTL(val) set_tsc_mode((val))
979 extern int get_tsc_mode(unsigned long adr);
980 extern int set_tsc_mode(unsigned int val);
982 #endif /* _ASM_X86_PROCESSOR_H */