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139ec7c416
It turns out that the most called ops, by several orders of magnitude, are the interrupt manipulation ops. These are obvious candidates for patching, so mark them up and create infrastructure for it. The method used is that the ops structure has a patch function, which is called for each place which needs to be patched: this returns a number of instructions (the rest are NOP-padded). Usually we can spare a register (%eax) for the binary patched code to use, but in a couple of critical places in entry.S we can't: we make the clobbers explicit at the call site, and manually clobber the allowed registers in debug mode as an extra check. And: Don't abuse CONFIG_DEBUG_KERNEL, add CONFIG_DEBUG_PARAVIRT. And: AK: Fix warnings in x86-64 alternative.c build And: AK: Fix compilation with defconfig And: ^From: Andrew Morton <akpm@osdl.org> Some binutlises still like to emit references to __stop_parainstructions and __start_parainstructions. And: AK: Fix warnings about unused variables when PARAVIRT is disabled. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com> Signed-off-by: Chris Wright <chrisw@sous-sol.org> Signed-off-by: Zachary Amsden <zach@vmware.com> Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org>
140 lines
2.6 KiB
C
140 lines
2.6 KiB
C
/*
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* include/asm-i386/irqflags.h
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*
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* IRQ flags handling
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*
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* This file gets included from lowlevel asm headers too, to provide
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* wrapped versions of the local_irq_*() APIs, based on the
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* raw_local_irq_*() functions from the lowlevel headers.
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*/
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#ifndef _ASM_IRQFLAGS_H
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#define _ASM_IRQFLAGS_H
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#ifdef CONFIG_PARAVIRT
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#include <asm/paravirt.h>
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#else
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#ifndef __ASSEMBLY__
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static inline unsigned long __raw_local_save_flags(void)
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{
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unsigned long flags;
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__asm__ __volatile__(
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"pushfl ; popl %0"
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: "=g" (flags)
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: /* no input */
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);
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return flags;
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}
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static inline void raw_local_irq_restore(unsigned long flags)
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{
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__asm__ __volatile__(
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"pushl %0 ; popfl"
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: /* no output */
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:"g" (flags)
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:"memory", "cc"
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);
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}
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static inline void raw_local_irq_disable(void)
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{
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__asm__ __volatile__("cli" : : : "memory");
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}
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static inline void raw_local_irq_enable(void)
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{
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__asm__ __volatile__("sti" : : : "memory");
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}
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/*
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* Used in the idle loop; sti takes one instruction cycle
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* to complete:
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*/
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static inline void raw_safe_halt(void)
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{
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__asm__ __volatile__("sti; hlt" : : : "memory");
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}
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/*
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* Used when interrupts are already enabled or to
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* shutdown the processor:
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*/
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static inline void halt(void)
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{
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__asm__ __volatile__("hlt": : :"memory");
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}
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/*
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* For spinlocks, etc:
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*/
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static inline unsigned long __raw_local_irq_save(void)
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{
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unsigned long flags = __raw_local_save_flags();
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raw_local_irq_disable();
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return flags;
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}
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#else
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#define DISABLE_INTERRUPTS(clobbers) cli
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#define ENABLE_INTERRUPTS(clobbers) sti
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#define ENABLE_INTERRUPTS_SYSEXIT sti; sysexit
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#define INTERRUPT_RETURN iret
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#define GET_CR0_INTO_EAX movl %cr0, %eax
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#endif /* __ASSEMBLY__ */
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#endif /* CONFIG_PARAVIRT */
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#ifndef __ASSEMBLY__
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#define raw_local_save_flags(flags) \
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do { (flags) = __raw_local_save_flags(); } while (0)
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#define raw_local_irq_save(flags) \
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do { (flags) = __raw_local_irq_save(); } while (0)
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static inline int raw_irqs_disabled_flags(unsigned long flags)
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{
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return !(flags & (1 << 9));
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}
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static inline int raw_irqs_disabled(void)
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{
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unsigned long flags = __raw_local_save_flags();
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return raw_irqs_disabled_flags(flags);
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}
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#endif /* __ASSEMBLY__ */
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/*
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* Do the CPU's IRQ-state tracing from assembly code. We call a
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* C function, so save all the C-clobbered registers:
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*/
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#ifdef CONFIG_TRACE_IRQFLAGS
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# define TRACE_IRQS_ON \
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pushl %eax; \
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pushl %ecx; \
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pushl %edx; \
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call trace_hardirqs_on; \
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popl %edx; \
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popl %ecx; \
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popl %eax;
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# define TRACE_IRQS_OFF \
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pushl %eax; \
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pushl %ecx; \
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pushl %edx; \
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call trace_hardirqs_off; \
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popl %edx; \
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popl %ecx; \
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popl %eax;
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#else
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# define TRACE_IRQS_ON
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# define TRACE_IRQS_OFF
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#endif
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#endif
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