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x86/entry: Use idtentry for interrupts

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Replace the extra interrupt handling code and reuse the existing idtentry
machinery. This moves the irq stack switching on 64-bit from ASM to C code;
32-bit already does the stack switching in C.

This requires to remove HAVE_IRQ_EXIT_ON_IRQ_STACK as the stack switch is
not longer in the low level entry code.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Andy Lutomirski <luto@kernel.org>
Link: https://lore.kernel.org/r/20200521202119.078690991@linutronix.de
This commit is contained in:
Thomas Gleixner 2020-05-21 22:05:37 +02:00
parent 0bf7c314ff
commit fa5e5c4092
9 changed files with 28 additions and 100 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

1
arch/x86/Kconfig
View file

@ -181,7 +181,6 @@ config X86
select HAVE_HW_BREAKPOINT select HAVE_HW_BREAKPOINT
select HAVE_IDE select HAVE_IDE
select HAVE_IOREMAP_PROT select HAVE_IOREMAP_PROT
select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64
select HAVE_IRQ_TIME_ACCOUNTING select HAVE_IRQ_TIME_ACCOUNTING
select HAVE_KERNEL_BZIP2 select HAVE_KERNEL_BZIP2
select HAVE_KERNEL_GZIP select HAVE_KERNEL_GZIP

31
arch/x86/entry/entry_32.S
View file

@ -1229,37 +1229,6 @@ SYM_FUNC_END(entry_INT80_32)
#endif #endif
.endm .endm
#ifdef CONFIG_X86_LOCAL_APIC
SYM_CODE_START_LOCAL(common_spurious)
ASM_CLAC
SAVE_ALL switch_stacks=1
ENCODE_FRAME_POINTER
TRACE_IRQS_OFF
movl %esp, %eax
movl PT_ORIG_EAX(%esp), %edx /* get the vector from stack */
movl $-1, PT_ORIG_EAX(%esp) /* no syscall to restart */
call smp_spurious_interrupt
jmp ret_from_intr
SYM_CODE_END(common_spurious)
#endif
/*
* the CPU automatically disables interrupts when executing an IRQ vector,
* so IRQ-flags tracing has to follow that:
*/
.p2align CONFIG_X86_L1_CACHE_SHIFT
SYM_CODE_START_LOCAL(common_interrupt)
ASM_CLAC
SAVE_ALL switch_stacks=1
ENCODE_FRAME_POINTER
TRACE_IRQS_OFF
movl %esp, %eax
movl PT_ORIG_EAX(%esp), %edx /* get the vector from stack */
movl $-1, PT_ORIG_EAX(%esp) /* no syscall to restart */
call do_IRQ
jmp ret_from_intr
SYM_CODE_END(common_interrupt)
#define BUILD_INTERRUPT3(name, nr, fn) \ #define BUILD_INTERRUPT3(name, nr, fn) \
SYM_FUNC_START(name) \ SYM_FUNC_START(name) \
ASM_CLAC; \ ASM_CLAC; \

31
arch/x86/entry/entry_64.S
View file

@ -737,32 +737,7 @@ SYM_CODE_START(interrupt_entry)
SYM_CODE_END(interrupt_entry) SYM_CODE_END(interrupt_entry)
_ASM_NOKPROBE(interrupt_entry) _ASM_NOKPROBE(interrupt_entry)
SYM_CODE_START_LOCAL(common_interrupt_return)
/* Interrupt entry/exit. */
/*
* The interrupt stubs push vector onto the stack and
* then jump to common_spurious/interrupt.
*/
SYM_CODE_START_LOCAL(common_spurious)
call interrupt_entry
UNWIND_HINT_REGS indirect=1
movq ORIG_RAX(%rdi), %rsi /* get vector from stack */
movq $-1, ORIG_RAX(%rdi) /* no syscall to restart */
call smp_spurious_interrupt /* rdi points to pt_regs */
jmp ret_from_intr
SYM_CODE_END(common_spurious)
_ASM_NOKPROBE(common_spurious)
/* common_interrupt is a hotpath. Align it */
.p2align CONFIG_X86_L1_CACHE_SHIFT
SYM_CODE_START_LOCAL(common_interrupt)
call interrupt_entry
UNWIND_HINT_REGS indirect=1
movq ORIG_RAX(%rdi), %rsi /* get vector from stack */
movq $-1, ORIG_RAX(%rdi) /* no syscall to restart */
call do_IRQ /* rdi points to pt_regs */
/* 0(%rsp): old RSP */
ret_from_intr: ret_from_intr:
DISABLE_INTERRUPTS(CLBR_ANY) DISABLE_INTERRUPTS(CLBR_ANY)
TRACE_IRQS_OFF TRACE_IRQS_OFF
@ -945,8 +920,8 @@ native_irq_return_ldt:
*/ */
jmp native_irq_return_iret jmp native_irq_return_iret
#endif #endif
SYM_CODE_END(common_interrupt) SYM_CODE_END(common_interrupt_return)
_ASM_NOKPROBE(common_interrupt) _ASM_NOKPROBE(common_interrupt_return)
/* /*
* APIC interrupts. * APIC interrupts.

1
arch/x86/include/asm/hw_irq.h
View file

@ -38,7 +38,6 @@ extern asmlinkage void error_interrupt(void);
extern asmlinkage void irq_work_interrupt(void); extern asmlinkage void irq_work_interrupt(void);
extern asmlinkage void uv_bau_message_intr1(void); extern asmlinkage void uv_bau_message_intr1(void);
extern asmlinkage void spurious_interrupt(void);
extern asmlinkage void spurious_apic_interrupt(void); extern asmlinkage void spurious_apic_interrupt(void);
extern asmlinkage void thermal_interrupt(void); extern asmlinkage void thermal_interrupt(void);
extern asmlinkage void reschedule_interrupt(void); extern asmlinkage void reschedule_interrupt(void);

10
arch/x86/include/asm/idtentry.h
View file

@ -417,7 +417,7 @@ SYM_CODE_START(irq_entries_start)
.rept (FIRST_SYSTEM_VECTOR - FIRST_EXTERNAL_VECTOR) .rept (FIRST_SYSTEM_VECTOR - FIRST_EXTERNAL_VECTOR)
UNWIND_HINT_IRET_REGS UNWIND_HINT_IRET_REGS
.byte 0x6a, vector .byte 0x6a, vector
jmp common_interrupt jmp asm_common_interrupt
nop nop
/* Ensure that the above is 8 bytes max */ /* Ensure that the above is 8 bytes max */
. = pos + 8 . = pos + 8
@ -434,7 +434,7 @@ SYM_CODE_START(spurious_entries_start)
.rept (NR_VECTORS - FIRST_SYSTEM_VECTOR) .rept (NR_VECTORS - FIRST_SYSTEM_VECTOR)
UNWIND_HINT_IRET_REGS UNWIND_HINT_IRET_REGS
.byte 0x6a, vector .byte 0x6a, vector
jmp common_spurious jmp asm_spurious_interrupt
nop nop
/* Ensure that the above is 8 bytes max */ /* Ensure that the above is 8 bytes max */
. = pos + 8 . = pos + 8
@ -506,6 +506,12 @@ DECLARE_IDTENTRY_DF(X86_TRAP_DF, exc_double_fault);
DECLARE_IDTENTRY_XENCB(X86_TRAP_OTHER, exc_xen_hypervisor_callback); DECLARE_IDTENTRY_XENCB(X86_TRAP_OTHER, exc_xen_hypervisor_callback);
#endif #endif
/* Device interrupts common/spurious */
DECLARE_IDTENTRY_IRQ(X86_TRAP_OTHER, common_interrupt);
#ifdef CONFIG_X86_LOCAL_APIC
DECLARE_IDTENTRY_IRQ(X86_TRAP_OTHER, spurious_interrupt);
#endif
#undef X86_TRAP_OTHER #undef X86_TRAP_OTHER
#endif #endif

1
arch/x86/include/asm/traps.h
View file

@ -43,7 +43,6 @@ asmlinkage void smp_deferred_error_interrupt(struct pt_regs *regs);
void smp_apic_timer_interrupt(struct pt_regs *regs); void smp_apic_timer_interrupt(struct pt_regs *regs);
void smp_error_interrupt(struct pt_regs *regs); void smp_error_interrupt(struct pt_regs *regs);
void smp_spurious_apic_interrupt(struct pt_regs *regs); void smp_spurious_apic_interrupt(struct pt_regs *regs);
void smp_spurious_interrupt(struct pt_regs *regs, unsigned long vector);
asmlinkage void smp_irq_move_cleanup_interrupt(void); asmlinkage void smp_irq_move_cleanup_interrupt(void);
#ifdef CONFIG_VMAP_STACK #ifdef CONFIG_VMAP_STACK

23
arch/x86/kernel/apic/apic.c
View file

@ -2121,9 +2121,9 @@ void __init register_lapic_address(unsigned long address)
*/ */
/** /**
* smp_spurious_interrupt - Catch all for interrupts raised on unused vectors * spurious_interrupt - Catch all for interrupts raised on unused vectors
* @regs: Pointer to pt_regs on stack * @regs: Pointer to pt_regs on stack
* @error_code: The vector number is in the lower 8 bits * @vector: The vector number
* *
* This is invoked from ASM entry code to catch all interrupts which * This is invoked from ASM entry code to catch all interrupts which
* trigger on an entry which is routed to the common_spurious idtentry * trigger on an entry which is routed to the common_spurious idtentry
@ -2131,18 +2131,10 @@ void __init register_lapic_address(unsigned long address)
* *
* Also called from smp_spurious_apic_interrupt(). * Also called from smp_spurious_apic_interrupt().
*/ */
__visible void __irq_entry smp_spurious_interrupt(struct pt_regs *regs, DEFINE_IDTENTRY_IRQ(spurious_interrupt)
unsigned long vector)
{ {
u32 v; u32 v;
entering_irq();
/*
* The push in the entry ASM code which stores the vector number on
* the stack in the error code slot is sign expanding. Just use the
* lower 8 bits.
*/
vector &= 0xFF;
trace_spurious_apic_entry(vector); trace_spurious_apic_entry(vector);
inc_irq_stat(irq_spurious_count); inc_irq_stat(irq_spurious_count);
@ -2163,21 +2155,22 @@ __visible void __irq_entry smp_spurious_interrupt(struct pt_regs *regs,
*/ */
v = apic_read(APIC_ISR + ((vector & ~0x1f) >> 1)); v = apic_read(APIC_ISR + ((vector & ~0x1f) >> 1));
if (v & (1 << (vector & 0x1f))) { if (v & (1 << (vector & 0x1f))) {
pr_info("Spurious interrupt (vector 0x%02lx) on CPU#%d. Acked\n", pr_info("Spurious interrupt (vector 0x%02x) on CPU#%d. Acked\n",
vector, smp_processor_id()); vector, smp_processor_id());
ack_APIC_irq(); ack_APIC_irq();
} else { } else {
pr_info("Spurious interrupt (vector 0x%02lx) on CPU#%d. Not pending!\n", pr_info("Spurious interrupt (vector 0x%02x) on CPU#%d. Not pending!\n",
vector, smp_processor_id()); vector, smp_processor_id());
} }
out: out:
trace_spurious_apic_exit(vector); trace_spurious_apic_exit(vector);
exiting_irq();
} }
__visible void smp_spurious_apic_interrupt(struct pt_regs *regs) __visible void smp_spurious_apic_interrupt(struct pt_regs *regs)
{ {
smp_spurious_interrupt(regs, SPURIOUS_APIC_VECTOR); entering_irq();
__spurious_interrupt(regs, SPURIOUS_APIC_VECTOR);
exiting_irq();
} }
/* /*

3
arch/x86/kernel/apic/msi.c
View file

@ -115,7 +115,8 @@ msi_set_affinity(struct irq_data *irqd, const struct cpumask *mask, bool force)
* denote it as spurious which is no harm as this is a rare event * denote it as spurious which is no harm as this is a rare event
* and interrupt handlers have to cope with spurious interrupts * and interrupt handlers have to cope with spurious interrupts
* anyway. If the vector is unused, then it is marked so it won't * anyway. If the vector is unused, then it is marked so it won't
* trigger the 'No irq handler for vector' warning in do_IRQ(). * trigger the 'No irq handler for vector' warning in
* common_interrupt().
* *
* This requires to hold vector lock to prevent concurrent updates to * This requires to hold vector lock to prevent concurrent updates to
* the affected vector. * the affected vector.

27
arch/x86/kernel/irq.c
View file

@ -20,6 +20,7 @@
#include <asm/mce.h> #include <asm/mce.h>
#include <asm/hw_irq.h> #include <asm/hw_irq.h>
#include <asm/desc.h> #include <asm/desc.h>
#include <asm/traps.h>
#define CREATE_TRACE_POINTS #define CREATE_TRACE_POINTS
#include <asm/trace/irq_vectors.h> #include <asm/trace/irq_vectors.h>
@ -232,37 +233,25 @@ static __always_inline void handle_irq(struct irq_desc *desc,
} }
/* /*
* do_IRQ handles all normal device IRQ's (the special * common_interrupt() handles all normal device IRQ's (the special SMP
* SMP cross-CPU interrupts have their own specific * cross-CPU interrupts have their own entry points).
* handlers).
*/ */
__visible void __irq_entry do_IRQ(struct pt_regs *regs, unsigned long vector) DEFINE_IDTENTRY_IRQ(common_interrupt)
{ {
struct pt_regs *old_regs = set_irq_regs(regs); struct pt_regs *old_regs = set_irq_regs(regs);
struct irq_desc *desc; struct irq_desc *desc;
entering_irq(); /* entry code tells RCU that we're not quiescent. Check it. */
/*
* The push in the entry ASM code which stores the vector number on
* the stack in the error code slot is sign expanding. Just use the
* lower 8 bits.
*/
vector &= 0xFF;
/* entering_irq() tells RCU that we're not quiescent. Check it. */
RCU_LOCKDEP_WARN(!rcu_is_watching(), "IRQ failed to wake up RCU"); RCU_LOCKDEP_WARN(!rcu_is_watching(), "IRQ failed to wake up RCU");
desc = __this_cpu_read(vector_irq[vector]); desc = __this_cpu_read(vector_irq[vector]);
if (likely(!IS_ERR_OR_NULL(desc))) { if (likely(!IS_ERR_OR_NULL(desc))) {
if (IS_ENABLED(CONFIG_X86_32)) handle_irq(desc, regs);
__handle_irq(desc, regs);
else
generic_handle_irq_desc(desc);
} else { } else {
ack_APIC_irq(); ack_APIC_irq();
if (desc == VECTOR_UNUSED) { if (desc == VECTOR_UNUSED) {
pr_emerg_ratelimited("%s: %d.%lu No irq handler for vector\n", pr_emerg_ratelimited("%s: %d.%u No irq handler for vector\n",
__func__, smp_processor_id(), __func__, smp_processor_id(),
vector); vector);
} else { } else {
@ -270,8 +259,6 @@ __visible void __irq_entry do_IRQ(struct pt_regs *regs, unsigned long vector)
} }
} }
exiting_irq();
set_irq_regs(old_regs); set_irq_regs(old_regs);
} }