1
linux/include/asm-i386/paravirt.h
Zachary Amsden 6cb9a8350a [PATCH] vmi: sched clock paravirt op fix
The custom_sched_clock hook is broken.  The result from sched_clock needs to
be in nanoseconds, not in CPU cycles.  The TSC is insufficient for this
purpose, because TSC is poorly defined in a virtual environment, and mostly
represents real world time instead of scheduled process time (which can be
interrupted without notice when a virtual machine is descheduled).

To make the scheduler consistent, we must expose a different nature of time,
that is scheduled time.  So deprecate this custom_sched_clock hack and turn it
into a paravirt-op, as it should have been all along.  This allows the tsc.c
code which converts cycles to nanoseconds to be shared by all paravirt-ops
backends.

It is unfortunate to add a new paravirt-op, but this is a very distinct
abstraction which is clearly different for all virtual machine
implementations, and it gets rid of an ugly indirect function which I
ashamedly admit I hacked in to try to get this to work earlier, and then even
got in the wrong units.

Signed-off-by: Zachary Amsden <zach@vmware.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-05 07:57:52 -08:00

559 lines
16 KiB
C

#ifndef __ASM_PARAVIRT_H
#define __ASM_PARAVIRT_H
/* Various instructions on x86 need to be replaced for
* para-virtualization: those hooks are defined here. */
#include <linux/linkage.h>
#include <linux/stringify.h>
#include <asm/page.h>
#ifdef CONFIG_PARAVIRT
/* These are the most performance critical ops, so we want to be able to patch
* callers */
#define PARAVIRT_IRQ_DISABLE 0
#define PARAVIRT_IRQ_ENABLE 1
#define PARAVIRT_RESTORE_FLAGS 2
#define PARAVIRT_SAVE_FLAGS 3
#define PARAVIRT_SAVE_FLAGS_IRQ_DISABLE 4
#define PARAVIRT_INTERRUPT_RETURN 5
#define PARAVIRT_STI_SYSEXIT 6
/* Bitmask of what can be clobbered: usually at least eax. */
#define CLBR_NONE 0x0
#define CLBR_EAX 0x1
#define CLBR_ECX 0x2
#define CLBR_EDX 0x4
#define CLBR_ANY 0x7
#ifndef __ASSEMBLY__
struct thread_struct;
struct Xgt_desc_struct;
struct tss_struct;
struct mm_struct;
struct paravirt_ops
{
unsigned int kernel_rpl;
int paravirt_enabled;
const char *name;
/*
* Patch may replace one of the defined code sequences with arbitrary
* code, subject to the same register constraints. This generally
* means the code is not free to clobber any registers other than EAX.
* The patch function should return the number of bytes of code
* generated, as we nop pad the rest in generic code.
*/
unsigned (*patch)(u8 type, u16 clobber, void *firstinsn, unsigned len);
void (*arch_setup)(void);
char *(*memory_setup)(void);
void (*init_IRQ)(void);
void (*banner)(void);
unsigned long (*get_wallclock)(void);
int (*set_wallclock)(unsigned long);
void (*time_init)(void);
/* All the function pointers here are declared as "fastcall"
so that we get a specific register-based calling
convention. This makes it easier to implement inline
assembler replacements. */
void (*cpuid)(unsigned int *eax, unsigned int *ebx,
unsigned int *ecx, unsigned int *edx);
unsigned long (*get_debugreg)(int regno);
void (*set_debugreg)(int regno, unsigned long value);
void (*clts)(void);
unsigned long (*read_cr0)(void);
void (*write_cr0)(unsigned long);
unsigned long (*read_cr2)(void);
void (*write_cr2)(unsigned long);
unsigned long (*read_cr3)(void);
void (*write_cr3)(unsigned long);
unsigned long (*read_cr4_safe)(void);
unsigned long (*read_cr4)(void);
void (*write_cr4)(unsigned long);
unsigned long (*save_fl)(void);
void (*restore_fl)(unsigned long);
void (*irq_disable)(void);
void (*irq_enable)(void);
void (*safe_halt)(void);
void (*halt)(void);
void (*wbinvd)(void);
/* err = 0/-EFAULT. wrmsr returns 0/-EFAULT. */
u64 (*read_msr)(unsigned int msr, int *err);
int (*write_msr)(unsigned int msr, u64 val);
u64 (*read_tsc)(void);
u64 (*read_pmc)(void);
u64 (*get_scheduled_cycles)(void);
void (*load_tr_desc)(void);
void (*load_gdt)(const struct Xgt_desc_struct *);
void (*load_idt)(const struct Xgt_desc_struct *);
void (*store_gdt)(struct Xgt_desc_struct *);
void (*store_idt)(struct Xgt_desc_struct *);
void (*set_ldt)(const void *desc, unsigned entries);
unsigned long (*store_tr)(void);
void (*load_tls)(struct thread_struct *t, unsigned int cpu);
void (*write_ldt_entry)(void *dt, int entrynum,
u32 low, u32 high);
void (*write_gdt_entry)(void *dt, int entrynum,
u32 low, u32 high);
void (*write_idt_entry)(void *dt, int entrynum,
u32 low, u32 high);
void (*load_esp0)(struct tss_struct *tss,
struct thread_struct *thread);
void (*set_iopl_mask)(unsigned mask);
void (*io_delay)(void);
void (*const_udelay)(unsigned long loops);
#ifdef CONFIG_X86_LOCAL_APIC
void (*apic_write)(unsigned long reg, unsigned long v);
void (*apic_write_atomic)(unsigned long reg, unsigned long v);
unsigned long (*apic_read)(unsigned long reg);
void (*setup_boot_clock)(void);
void (*setup_secondary_clock)(void);
#endif
void (*flush_tlb_user)(void);
void (*flush_tlb_kernel)(void);
void (*flush_tlb_single)(u32 addr);
void (*alloc_pt)(u32 pfn);
void (*alloc_pd)(u32 pfn);
void (*alloc_pd_clone)(u32 pfn, u32 clonepfn, u32 start, u32 count);
void (*release_pt)(u32 pfn);
void (*release_pd)(u32 pfn);
void (*set_pte)(pte_t *ptep, pte_t pteval);
void (*set_pte_at)(struct mm_struct *mm, u32 addr, pte_t *ptep, pte_t pteval);
void (*set_pmd)(pmd_t *pmdp, pmd_t pmdval);
void (*pte_update)(struct mm_struct *mm, u32 addr, pte_t *ptep);
void (*pte_update_defer)(struct mm_struct *mm, u32 addr, pte_t *ptep);
#ifdef CONFIG_X86_PAE
void (*set_pte_atomic)(pte_t *ptep, pte_t pteval);
void (*set_pte_present)(struct mm_struct *mm, unsigned long addr, pte_t *ptep, pte_t pte);
void (*set_pud)(pud_t *pudp, pud_t pudval);
void (*pte_clear)(struct mm_struct *mm, unsigned long addr, pte_t *ptep);
void (*pmd_clear)(pmd_t *pmdp);
#endif
void (*set_lazy_mode)(int mode);
/* These two are jmp to, not actually called. */
void (*irq_enable_sysexit)(void);
void (*iret)(void);
void (*startup_ipi_hook)(int phys_apicid, unsigned long start_eip, unsigned long start_esp);
};
/* Mark a paravirt probe function. */
#define paravirt_probe(fn) \
static asmlinkage void (*__paravirtprobe_##fn)(void) __attribute_used__ \
__attribute__((__section__(".paravirtprobe"))) = fn
extern struct paravirt_ops paravirt_ops;
#define paravirt_enabled() (paravirt_ops.paravirt_enabled)
static inline void load_esp0(struct tss_struct *tss,
struct thread_struct *thread)
{
paravirt_ops.load_esp0(tss, thread);
}
#define ARCH_SETUP paravirt_ops.arch_setup();
static inline unsigned long get_wallclock(void)
{
return paravirt_ops.get_wallclock();
}
static inline int set_wallclock(unsigned long nowtime)
{
return paravirt_ops.set_wallclock(nowtime);
}
static inline void do_time_init(void)
{
return paravirt_ops.time_init();
}
/* The paravirtualized CPUID instruction. */
static inline void __cpuid(unsigned int *eax, unsigned int *ebx,
unsigned int *ecx, unsigned int *edx)
{
paravirt_ops.cpuid(eax, ebx, ecx, edx);
}
/*
* These special macros can be used to get or set a debugging register
*/
#define get_debugreg(var, reg) var = paravirt_ops.get_debugreg(reg)
#define set_debugreg(val, reg) paravirt_ops.set_debugreg(reg, val)
#define clts() paravirt_ops.clts()
#define read_cr0() paravirt_ops.read_cr0()
#define write_cr0(x) paravirt_ops.write_cr0(x)
#define read_cr2() paravirt_ops.read_cr2()
#define write_cr2(x) paravirt_ops.write_cr2(x)
#define read_cr3() paravirt_ops.read_cr3()
#define write_cr3(x) paravirt_ops.write_cr3(x)
#define read_cr4() paravirt_ops.read_cr4()
#define read_cr4_safe(x) paravirt_ops.read_cr4_safe()
#define write_cr4(x) paravirt_ops.write_cr4(x)
static inline void raw_safe_halt(void)
{
paravirt_ops.safe_halt();
}
static inline void halt(void)
{
paravirt_ops.safe_halt();
}
#define wbinvd() paravirt_ops.wbinvd()
#define get_kernel_rpl() (paravirt_ops.kernel_rpl)
#define rdmsr(msr,val1,val2) do { \
int _err; \
u64 _l = paravirt_ops.read_msr(msr,&_err); \
val1 = (u32)_l; \
val2 = _l >> 32; \
} while(0)
#define wrmsr(msr,val1,val2) do { \
u64 _l = ((u64)(val2) << 32) | (val1); \
paravirt_ops.write_msr((msr), _l); \
} while(0)
#define rdmsrl(msr,val) do { \
int _err; \
val = paravirt_ops.read_msr((msr),&_err); \
} while(0)
#define wrmsrl(msr,val) (paravirt_ops.write_msr((msr),(val)))
#define wrmsr_safe(msr,a,b) ({ \
u64 _l = ((u64)(b) << 32) | (a); \
paravirt_ops.write_msr((msr),_l); \
})
/* rdmsr with exception handling */
#define rdmsr_safe(msr,a,b) ({ \
int _err; \
u64 _l = paravirt_ops.read_msr(msr,&_err); \
(*a) = (u32)_l; \
(*b) = _l >> 32; \
_err; })
#define rdtsc(low,high) do { \
u64 _l = paravirt_ops.read_tsc(); \
low = (u32)_l; \
high = _l >> 32; \
} while(0)
#define rdtscl(low) do { \
u64 _l = paravirt_ops.read_tsc(); \
low = (int)_l; \
} while(0)
#define rdtscll(val) (val = paravirt_ops.read_tsc())
#define get_scheduled_cycles(val) (val = paravirt_ops.get_scheduled_cycles())
#define write_tsc(val1,val2) wrmsr(0x10, val1, val2)
#define rdpmc(counter,low,high) do { \
u64 _l = paravirt_ops.read_pmc(); \
low = (u32)_l; \
high = _l >> 32; \
} while(0)
#define load_TR_desc() (paravirt_ops.load_tr_desc())
#define load_gdt(dtr) (paravirt_ops.load_gdt(dtr))
#define load_idt(dtr) (paravirt_ops.load_idt(dtr))
#define set_ldt(addr, entries) (paravirt_ops.set_ldt((addr), (entries)))
#define store_gdt(dtr) (paravirt_ops.store_gdt(dtr))
#define store_idt(dtr) (paravirt_ops.store_idt(dtr))
#define store_tr(tr) ((tr) = paravirt_ops.store_tr())
#define load_TLS(t,cpu) (paravirt_ops.load_tls((t),(cpu)))
#define write_ldt_entry(dt, entry, low, high) \
(paravirt_ops.write_ldt_entry((dt), (entry), (low), (high)))
#define write_gdt_entry(dt, entry, low, high) \
(paravirt_ops.write_gdt_entry((dt), (entry), (low), (high)))
#define write_idt_entry(dt, entry, low, high) \
(paravirt_ops.write_idt_entry((dt), (entry), (low), (high)))
#define set_iopl_mask(mask) (paravirt_ops.set_iopl_mask(mask))
/* The paravirtualized I/O functions */
static inline void slow_down_io(void) {
paravirt_ops.io_delay();
#ifdef REALLY_SLOW_IO
paravirt_ops.io_delay();
paravirt_ops.io_delay();
paravirt_ops.io_delay();
#endif
}
#ifdef CONFIG_X86_LOCAL_APIC
/*
* Basic functions accessing APICs.
*/
static inline void apic_write(unsigned long reg, unsigned long v)
{
paravirt_ops.apic_write(reg,v);
}
static inline void apic_write_atomic(unsigned long reg, unsigned long v)
{
paravirt_ops.apic_write_atomic(reg,v);
}
static inline unsigned long apic_read(unsigned long reg)
{
return paravirt_ops.apic_read(reg);
}
static inline void setup_boot_clock(void)
{
paravirt_ops.setup_boot_clock();
}
static inline void setup_secondary_clock(void)
{
paravirt_ops.setup_secondary_clock();
}
#endif
#ifdef CONFIG_SMP
static inline void startup_ipi_hook(int phys_apicid, unsigned long start_eip,
unsigned long start_esp)
{
return paravirt_ops.startup_ipi_hook(phys_apicid, start_eip, start_esp);
}
#endif
#define __flush_tlb() paravirt_ops.flush_tlb_user()
#define __flush_tlb_global() paravirt_ops.flush_tlb_kernel()
#define __flush_tlb_single(addr) paravirt_ops.flush_tlb_single(addr)
#define paravirt_alloc_pt(pfn) paravirt_ops.alloc_pt(pfn)
#define paravirt_release_pt(pfn) paravirt_ops.release_pt(pfn)
#define paravirt_alloc_pd(pfn) paravirt_ops.alloc_pd(pfn)
#define paravirt_alloc_pd_clone(pfn, clonepfn, start, count) \
paravirt_ops.alloc_pd_clone(pfn, clonepfn, start, count)
#define paravirt_release_pd(pfn) paravirt_ops.release_pd(pfn)
static inline void set_pte(pte_t *ptep, pte_t pteval)
{
paravirt_ops.set_pte(ptep, pteval);
}
static inline void set_pte_at(struct mm_struct *mm, u32 addr, pte_t *ptep, pte_t pteval)
{
paravirt_ops.set_pte_at(mm, addr, ptep, pteval);
}
static inline void set_pmd(pmd_t *pmdp, pmd_t pmdval)
{
paravirt_ops.set_pmd(pmdp, pmdval);
}
static inline void pte_update(struct mm_struct *mm, u32 addr, pte_t *ptep)
{
paravirt_ops.pte_update(mm, addr, ptep);
}
static inline void pte_update_defer(struct mm_struct *mm, u32 addr, pte_t *ptep)
{
paravirt_ops.pte_update_defer(mm, addr, ptep);
}
#ifdef CONFIG_X86_PAE
static inline void set_pte_atomic(pte_t *ptep, pte_t pteval)
{
paravirt_ops.set_pte_atomic(ptep, pteval);
}
static inline void set_pte_present(struct mm_struct *mm, unsigned long addr, pte_t *ptep, pte_t pte)
{
paravirt_ops.set_pte_present(mm, addr, ptep, pte);
}
static inline void set_pud(pud_t *pudp, pud_t pudval)
{
paravirt_ops.set_pud(pudp, pudval);
}
static inline void pte_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
{
paravirt_ops.pte_clear(mm, addr, ptep);
}
static inline void pmd_clear(pmd_t *pmdp)
{
paravirt_ops.pmd_clear(pmdp);
}
#endif
/* Lazy mode for batching updates / context switch */
#define PARAVIRT_LAZY_NONE 0
#define PARAVIRT_LAZY_MMU 1
#define PARAVIRT_LAZY_CPU 2
#define __HAVE_ARCH_ENTER_LAZY_CPU_MODE
#define arch_enter_lazy_cpu_mode() paravirt_ops.set_lazy_mode(PARAVIRT_LAZY_CPU)
#define arch_leave_lazy_cpu_mode() paravirt_ops.set_lazy_mode(PARAVIRT_LAZY_NONE)
#define __HAVE_ARCH_ENTER_LAZY_MMU_MODE
#define arch_enter_lazy_mmu_mode() paravirt_ops.set_lazy_mode(PARAVIRT_LAZY_MMU)
#define arch_leave_lazy_mmu_mode() paravirt_ops.set_lazy_mode(PARAVIRT_LAZY_NONE)
/* These all sit in the .parainstructions section to tell us what to patch. */
struct paravirt_patch {
u8 *instr; /* original instructions */
u8 instrtype; /* type of this instruction */
u8 len; /* length of original instruction */
u16 clobbers; /* what registers you may clobber */
};
#define paravirt_alt(insn_string, typenum, clobber) \
"771:\n\t" insn_string "\n" "772:\n" \
".pushsection .parainstructions,\"a\"\n" \
" .long 771b\n" \
" .byte " __stringify(typenum) "\n" \
" .byte 772b-771b\n" \
" .short " __stringify(clobber) "\n" \
".popsection"
static inline unsigned long __raw_local_save_flags(void)
{
unsigned long f;
__asm__ __volatile__(paravirt_alt( "pushl %%ecx; pushl %%edx;"
"call *%1;"
"popl %%edx; popl %%ecx",
PARAVIRT_SAVE_FLAGS, CLBR_NONE)
: "=a"(f): "m"(paravirt_ops.save_fl)
: "memory", "cc");
return f;
}
static inline void raw_local_irq_restore(unsigned long f)
{
__asm__ __volatile__(paravirt_alt( "pushl %%ecx; pushl %%edx;"
"call *%1;"
"popl %%edx; popl %%ecx",
PARAVIRT_RESTORE_FLAGS, CLBR_EAX)
: "=a"(f) : "m" (paravirt_ops.restore_fl), "0"(f)
: "memory", "cc");
}
static inline void raw_local_irq_disable(void)
{
__asm__ __volatile__(paravirt_alt( "pushl %%ecx; pushl %%edx;"
"call *%0;"
"popl %%edx; popl %%ecx",
PARAVIRT_IRQ_DISABLE, CLBR_EAX)
: : "m" (paravirt_ops.irq_disable)
: "memory", "eax", "cc");
}
static inline void raw_local_irq_enable(void)
{
__asm__ __volatile__(paravirt_alt( "pushl %%ecx; pushl %%edx;"
"call *%0;"
"popl %%edx; popl %%ecx",
PARAVIRT_IRQ_ENABLE, CLBR_EAX)
: : "m" (paravirt_ops.irq_enable)
: "memory", "eax", "cc");
}
static inline unsigned long __raw_local_irq_save(void)
{
unsigned long f;
__asm__ __volatile__(paravirt_alt( "pushl %%ecx; pushl %%edx;"
"call *%1; pushl %%eax;"
"call *%2; popl %%eax;"
"popl %%edx; popl %%ecx",
PARAVIRT_SAVE_FLAGS_IRQ_DISABLE,
CLBR_NONE)
: "=a"(f)
: "m" (paravirt_ops.save_fl),
"m" (paravirt_ops.irq_disable)
: "memory", "cc");
return f;
}
#define CLI_STRING paravirt_alt("pushl %%ecx; pushl %%edx;" \
"call *paravirt_ops+%c[irq_disable];" \
"popl %%edx; popl %%ecx", \
PARAVIRT_IRQ_DISABLE, CLBR_EAX)
#define STI_STRING paravirt_alt("pushl %%ecx; pushl %%edx;" \
"call *paravirt_ops+%c[irq_enable];" \
"popl %%edx; popl %%ecx", \
PARAVIRT_IRQ_ENABLE, CLBR_EAX)
#define CLI_STI_CLOBBERS , "%eax"
#define CLI_STI_INPUT_ARGS \
, \
[irq_disable] "i" (offsetof(struct paravirt_ops, irq_disable)), \
[irq_enable] "i" (offsetof(struct paravirt_ops, irq_enable))
#else /* __ASSEMBLY__ */
#define PARA_PATCH(ptype, clobbers, ops) \
771:; \
ops; \
772:; \
.pushsection .parainstructions,"a"; \
.long 771b; \
.byte ptype; \
.byte 772b-771b; \
.short clobbers; \
.popsection
#define INTERRUPT_RETURN \
PARA_PATCH(PARAVIRT_INTERRUPT_RETURN, CLBR_ANY, \
jmp *%cs:paravirt_ops+PARAVIRT_iret)
#define DISABLE_INTERRUPTS(clobbers) \
PARA_PATCH(PARAVIRT_IRQ_DISABLE, clobbers, \
pushl %ecx; pushl %edx; \
call *paravirt_ops+PARAVIRT_irq_disable; \
popl %edx; popl %ecx) \
#define ENABLE_INTERRUPTS(clobbers) \
PARA_PATCH(PARAVIRT_IRQ_ENABLE, clobbers, \
pushl %ecx; pushl %edx; \
call *%cs:paravirt_ops+PARAVIRT_irq_enable; \
popl %edx; popl %ecx)
#define ENABLE_INTERRUPTS_SYSEXIT \
PARA_PATCH(PARAVIRT_STI_SYSEXIT, CLBR_ANY, \
jmp *%cs:paravirt_ops+PARAVIRT_irq_enable_sysexit)
#define GET_CR0_INTO_EAX \
call *paravirt_ops+PARAVIRT_read_cr0
#endif /* __ASSEMBLY__ */
#endif /* CONFIG_PARAVIRT */
#endif /* __ASM_PARAVIRT_H */