[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] [Xen-devel] [patch 11/26] Xen-paravirt_ops: Use patch site IDs computed from offset in paravirt_ops structure
Use patch type identifiers derived from the offset of the operation in the paravirt_ops structure. This avoids having to maintain a separate enum for patch site types. This patch also drops the fused save_fl+cli operation, which doesn't really add much and makes things more complex. Signed-off-by: Jeremy Fitzhardinge <jeremy@xxxxxxxxxxxxx> Cc: Rusty Russell <rusty@xxxxxxxxxxxxxxx> Cc: Zachary Amsden <zach@xxxxxxxxxx> --- arch/i386/kernel/asm-offsets.c | 5 + arch/i386/kernel/paravirt.c | 14 ++--- arch/i386/kernel/vmi.c | 38 ++------------ include/asm-i386/paravirt.h | 107 +++++++++++++++++++--------------------- 4 files changed, 70 insertions(+), 94 deletions(-) =================================================================== --- a/arch/i386/kernel/asm-offsets.c +++ b/arch/i386/kernel/asm-offsets.c @@ -110,5 +110,10 @@ void foo(void) OFFSET(PARAVIRT_irq_enable_sysexit, paravirt_ops, irq_enable_sysexit); OFFSET(PARAVIRT_iret, paravirt_ops, iret); OFFSET(PARAVIRT_read_cr0, paravirt_ops, read_cr0); + + DEFINE(PARAVIRT_IRQ_DISABLE, PARAVIRT_PATCH(irq_disable)); + DEFINE(PARAVIRT_IRQ_ENABLE, PARAVIRT_PATCH(irq_enable)); + DEFINE(PARAVIRT_STI_SYSEXIT, PARAVIRT_PATCH(irq_enable_sysexit)); + DEFINE(PARAVIRT_INTERRUPT_RETURN, PARAVIRT_PATCH(iret)); #endif } =================================================================== --- a/arch/i386/kernel/paravirt.c +++ b/arch/i386/kernel/paravirt.c @@ -57,7 +57,6 @@ DEF_NATIVE(sti, "sti"); DEF_NATIVE(sti, "sti"); DEF_NATIVE(popf, "push %eax; popf"); DEF_NATIVE(pushf, "pushf; pop %eax"); -DEF_NATIVE(pushf_cli, "pushf; pop %eax; cli"); DEF_NATIVE(iret, "iret"); DEF_NATIVE(sti_sysexit, "sti; sysexit"); @@ -65,13 +64,12 @@ static const struct native_insns { const char *start, *end; } native_insns[] = { - [PARAVIRT_IRQ_DISABLE] = { start_cli, end_cli }, - [PARAVIRT_IRQ_ENABLE] = { start_sti, end_sti }, - [PARAVIRT_RESTORE_FLAGS] = { start_popf, end_popf }, - [PARAVIRT_SAVE_FLAGS] = { start_pushf, end_pushf }, - [PARAVIRT_SAVE_FLAGS_IRQ_DISABLE] = { start_pushf_cli, end_pushf_cli }, - [PARAVIRT_INTERRUPT_RETURN] = { start_iret, end_iret }, - [PARAVIRT_STI_SYSEXIT] = { start_sti_sysexit, end_sti_sysexit }, + [PARAVIRT_PATCH(irq_disable)] = { start_cli, end_cli }, + [PARAVIRT_PATCH(irq_enable)] = { start_sti, end_sti }, + [PARAVIRT_PATCH(restore_fl)] = { start_popf, end_popf }, + [PARAVIRT_PATCH(save_fl)] = { start_pushf, end_pushf }, + [PARAVIRT_PATCH(iret)] = { start_iret, end_iret }, + [PARAVIRT_PATCH(irq_enable_sysexit)] = { start_sti_sysexit, end_sti_sysexit }, }; static unsigned native_patch(u8 type, u16 clobbers, void *insns, unsigned len) =================================================================== --- a/arch/i386/kernel/vmi.c +++ b/arch/i386/kernel/vmi.c @@ -78,11 +78,6 @@ struct { #define MNEM_JMP 0xe9 #define MNEM_RET 0xc3 -static char irq_save_disable_callout[] = { - MNEM_CALL, 0, 0, 0, 0, - MNEM_CALL, 0, 0, 0, 0, - MNEM_RET -}; #define IRQ_PATCH_INT_MASK 0 #define IRQ_PATCH_DISABLE 5 @@ -130,33 +125,17 @@ static unsigned vmi_patch(u8 type, u16 c static unsigned vmi_patch(u8 type, u16 clobbers, void *insns, unsigned len) { switch (type) { - case PARAVIRT_IRQ_DISABLE: + case PARAVIRT_PATCH(irq_disable): return patch_internal(VMI_CALL_DisableInterrupts, len, insns); - case PARAVIRT_IRQ_ENABLE: + case PARAVIRT_PATCH(irq_enable): return patch_internal(VMI_CALL_EnableInterrupts, len, insns); - case PARAVIRT_RESTORE_FLAGS: + case PARAVIRT_PATCH(restore_fl): return patch_internal(VMI_CALL_SetInterruptMask, len, insns); - case PARAVIRT_SAVE_FLAGS: + case PARAVIRT_PATCH(save_fl): return patch_internal(VMI_CALL_GetInterruptMask, len, insns); - case PARAVIRT_SAVE_FLAGS_IRQ_DISABLE: - if (len >= 10) { - patch_internal(VMI_CALL_GetInterruptMask, len, insns); - patch_internal(VMI_CALL_DisableInterrupts, len-5, insns+5); - return 10; - } else { - /* - * You bastards didn't leave enough room to - * patch save_flags_irq_disable inline. Patch - * to a helper - */ - BUG_ON(len < 5); - *(char *)insns = MNEM_CALL; - patch_offset(insns, irq_save_disable_callout); - return 5; - } - case PARAVIRT_INTERRUPT_RETURN: + case PARAVIRT_PATCH(iret): return patch_internal(VMI_CALL_IRET, len, insns); - case PARAVIRT_STI_SYSEXIT: + case PARAVIRT_PATCH(irq_enable_sysexit): return patch_internal(VMI_CALL_SYSEXIT, len, insns); default: break; @@ -733,11 +712,6 @@ static inline int __init activate_vmi(vo para_fill(restore_fl, SetInterruptMask); para_fill(irq_disable, DisableInterrupts); para_fill(irq_enable, EnableInterrupts); - /* irq_save_disable !!! sheer pain */ - patch_offset(&irq_save_disable_callout[IRQ_PATCH_INT_MASK], - (char *)paravirt_ops.save_fl); - patch_offset(&irq_save_disable_callout[IRQ_PATCH_DISABLE], - (char *)paravirt_ops.irq_disable); #ifndef CONFIG_NO_IDLE_HZ para_fill(safe_halt, Halt); #else =================================================================== --- a/include/asm-i386/paravirt.h +++ b/include/asm-i386/paravirt.h @@ -4,18 +4,7 @@ * para-virtualization: those hooks are defined here. */ #ifdef CONFIG_PARAVIRT -#include <linux/stringify.h> #include <asm/page.h> - -/* 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 @@ -26,6 +15,23 @@ #ifndef __ASSEMBLY__ #include <linux/types.h> + +#define paravirt_type(type) [paravirt_typenum] "i" (type) +#define paravirt_clobber(clobber) [paravirt_clobber] "i" (clobber) + +#define PARAVIRT_PATCH(x) (offsetof(struct paravirt_ops, x) / sizeof(void *)) + +#define _paravirt_alt(insn_string, type, clobber) \ + "771:\n\t" insn_string "\n" "772:\n" \ + ".pushsection .parainstructions,\"a\"\n" \ + " .long 771b\n" \ + " .byte " type "\n" \ + " .byte 772b-771b\n" \ + " .short " clobber "\n" \ + ".popsection\n" + +#define paravirt_alt(insn_string) \ + _paravirt_alt(insn_string, "%c[paravirt_typenum]", "%c[paravirt_clobber]") struct thread_struct; struct Xgt_desc_struct; @@ -512,24 +518,16 @@ extern struct paravirt_patch_site __star extern struct paravirt_patch_site __start_parainstructions[], __stop_parainstructions[]; -#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) + "popl %%edx; popl %%ecx") + : "=a"(f): "m"(paravirt_ops.save_fl), + paravirt_type(PARAVIRT_PATCH(save_fl)), + paravirt_clobber(CLBR_NONE) : "memory", "cc"); return f; } @@ -538,9 +536,10 @@ static inline void raw_local_irq_restore { __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) + "popl %%edx; popl %%ecx") + : "=a"(f) : "m" (paravirt_ops.restore_fl), "0"(f), + paravirt_type(PARAVIRT_PATCH(restore_fl)), + paravirt_clobber(CLBR_EAX) : "memory", "cc"); } @@ -548,9 +547,10 @@ static inline void raw_local_irq_disable { __asm__ __volatile__(paravirt_alt( "pushl %%ecx; pushl %%edx;" "call *%0;" - "popl %%edx; popl %%ecx", - PARAVIRT_IRQ_DISABLE, CLBR_EAX) - : : "m" (paravirt_ops.irq_disable) + "popl %%edx; popl %%ecx") + : : "m" (paravirt_ops.irq_disable), + paravirt_type(PARAVIRT_PATCH(irq_disable)), + paravirt_clobber(CLBR_EAX) : "memory", "eax", "cc"); } @@ -558,9 +558,10 @@ static inline void raw_local_irq_enable( { __asm__ __volatile__(paravirt_alt( "pushl %%ecx; pushl %%edx;" "call *%0;" - "popl %%edx; popl %%ecx", - PARAVIRT_IRQ_ENABLE, CLBR_EAX) - : : "m" (paravirt_ops.irq_enable) + "popl %%edx; popl %%ecx") + : : "m" (paravirt_ops.irq_enable), + paravirt_type(PARAVIRT_PATCH(irq_enable)), + paravirt_clobber(CLBR_EAX) : "memory", "eax", "cc"); } @@ -568,33 +569,31 @@ static inline unsigned long __raw_local_ { 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"); + f = __raw_local_save_flags(); + raw_local_irq_disable(); + 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_STRING _paravirt_alt("pushl %%ecx; pushl %%edx;" \ + "call *paravirt_ops+%c[irq_disable];" \ + "popl %%edx; popl %%ecx", \ + "%c[paravirt_cli_type]", "%c[paravirt_clobber]") + +#define STI_STRING _paravirt_alt("pushl %%ecx; pushl %%edx;" \ + "call *paravirt_ops+%c[irq_enable];" \ + "popl %%edx; popl %%ecx", \ + "%c[paravirt_cli_type]", "%c[paravirt_clobber]") + + #define CLI_STI_CLOBBERS , "%eax" -#define CLI_STI_INPUT_ARGS \ +#define CLI_STI_INPUT_ARGS \ , \ - [irq_disable] "i" (offsetof(struct paravirt_ops, irq_disable)), \ - [irq_enable] "i" (offsetof(struct paravirt_ops, irq_enable)) + [irq_disable] "i" (offsetof(struct paravirt_ops, irq_disable)), \ + [irq_enable] "i" (offsetof(struct paravirt_ops, irq_enable)), \ + [paravirt_cli_type] "i" (PARAVIRT_PATCH(irq_disable)), \ + [paravirt_sti_type] "i" (PARAVIRT_PATCH(irq_disable)), \ + paravirt_clobber(CLBR_NONE) #else /* __ASSEMBLY__ */ -- _______________________________________________ Xen-devel mailing list Xen-devel@xxxxxxxxxxxxxxxxxxx http://lists.xensource.com/xen-devel
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