diff -urN linux-2.5.8-pre2/arch/i386/kernel/entry.S linux/arch/i386/kernel/entry.S
--- linux-2.5.8-pre2/arch/i386/kernel/entry.S Sat Apr 6 11:47:52 2002
+++ linux/arch/i386/kernel/entry.S Sat Apr 6 12:58:37 2002
@@ -47,6 +47,7 @@
#include <asm/errno.h>
#include <asm/segment.h>
#include <asm/smp.h>
+#include <asm/irq_vectors.h>
EBX = 0x00
ECX = 0x04
@@ -94,12 +95,12 @@
#ifdef CONFIG_PREEMPT
#define preempt_stop cli
-#define init_ret_intr \
- cli; \
- decl TI_PRE_COUNT(%ebx);
+#define INC_PRE_COUNT(reg) incl TI_PRE_COUNT(reg);
+#define DEC_PRE_COUNT(reg) decl TI_PRE_COUNT(reg);
#else
#define preempt_stop
-#define init_ret_intr
+#define INC_PRE_COUNT(reg)
+#define DEC_PRE_COUNT(reg)
#define resume_kernel restore_all
#endif
@@ -210,9 +211,9 @@
# userspace resumption stub bypassing syscall exit tracing
ALIGN
-ENTRY(ret_from_intr)
- GET_THREAD_INFO(%ebx)
- init_ret_intr
+ret_from_intr:
+ preempt_stop
+ DEC_PRE_COUNT(%ebx)
ret_from_exception:
movl EFLAGS(%esp), %eax # mix EFLAGS and CS
movb CS(%esp), %al
@@ -335,6 +336,67 @@
movl $-ENOSYS,EAX(%esp)
jmp resume_userspace
+/*
+ * Build the entry stubs and pointer table with
+ * some assembler magic.
+ */
+.data
+ENTRY(interrupt)
+.text
+
+vector=0
+ENTRY(irq_entries_start)
+.rept NR_IRQS
+ ALIGN
+1: pushl $vector-256
+ jmp common_interrupt
+.data
+ .long 1b
+.text
+vector=vector+1
+.endr
+
+ ALIGN
+common_interrupt:
+ SAVE_ALL
+ GET_THREAD_INFO(%ebx)
+ INC_PRE_COUNT(%ebx)
+ call SYMBOL_NAME(do_IRQ)
+ jmp ret_from_intr
+
+#define BUILD_INTERRUPT(name, nr) \
+ENTRY(name) \
+ pushl $nr-256; \
+ SAVE_ALL \
+ GET_THREAD_INFO(%ebx); \
+ INC_PRE_COUNT(%ebx) \
+ call SYMBOL_NAME(smp_/**/name); \
+ jmp ret_from_intr;
+
+/*
+ * The following vectors are part of the Linux architecture, there
+ * is no hardware IRQ pin equivalent for them, they are triggered
+ * through the ICC by us (IPIs)
+ */
+#ifdef CONFIG_SMP
+BUILD_INTERRUPT(reschedule_interrupt,RESCHEDULE_VECTOR)
+BUILD_INTERRUPT(invalidate_interrupt,INVALIDATE_TLB_VECTOR)
+BUILD_INTERRUPT(call_function_interrupt,CALL_FUNCTION_VECTOR)
+#endif
+
+/*
+ * every pentium local APIC has two 'local interrupts', with a
+ * soft-definable vector attached to both interrupts, one of
+ * which is a timer interrupt, the other one is error counter
+ * overflow. Linux uses the local APIC timer interrupt to get
+ * a much simpler SMP time architecture:
+ */
+#ifdef CONFIG_X86_LOCAL_APIC
+BUILD_INTERRUPT(apic_timer_interrupt,LOCAL_TIMER_VECTOR)
+BUILD_INTERRUPT(error_interrupt,ERROR_APIC_VECTOR)
+BUILD_INTERRUPT(spurious_interrupt,SPURIOUS_APIC_VECTOR)
+#endif
+
ENTRY(divide_error)
pushl $0 # no error code
pushl $ SYMBOL_NAME(do_divide_error)
diff -urN linux-2.5.8-pre2/arch/i386/kernel/i8259.c linux/arch/i386/kernel/i8259.c
--- linux-2.5.8-pre2/arch/i386/kernel/i8259.c Thu Mar 7 21:18:57 2002
+++ linux/arch/i386/kernel/i8259.c Sat Apr 6 11:48:15 2002
@@ -25,102 +25,6 @@
#include <linux/irq.h>
/*
- * Common place to define all x86 IRQ vectors
- *
- * This builds up the IRQ handler stubs using some ugly macros in irq.h
- *
- * These macros create the low-level assembly IRQ routines that save
- * register context and call do_IRQ(). do_IRQ() then does all the
- * operations that are needed to keep the AT (or SMP IOAPIC)
- * interrupt-controller happy.
- */
-
-BUILD_COMMON_IRQ()
-
-#define BI(x,y) \
- BUILD_IRQ(x##y)
-
-#define BUILD_16_IRQS(x) \
- BI(x,0) BI(x,1) BI(x,2) BI(x,3) \
- BI(x,4) BI(x,5) BI(x,6) BI(x,7) \
- BI(x,8) BI(x,9) BI(x,a) BI(x,b) \
- BI(x,c) BI(x,d) BI(x,e) BI(x,f)
-
-/*
- * ISA PIC or low IO-APIC triggered (INTA-cycle or APIC) interrupts:
- * (these are usually mapped to vectors 0x20-0x2f)
- */
-BUILD_16_IRQS(0x0)
-
-#ifdef CONFIG_X86_IO_APIC
-/*
- * The IO-APIC gives us many more interrupt sources. Most of these
- * are unused but an SMP system is supposed to have enough memory ...
- * sometimes (mostly wrt. hw bugs) we get corrupted vectors all
- * across the spectrum, so we really want to be prepared to get all
- * of these. Plus, more powerful systems might have more than 64
- * IO-APIC registers.
- *
- * (these are usually mapped into the 0x30-0xff vector range)
- */
- BUILD_16_IRQS(0x1) BUILD_16_IRQS(0x2) BUILD_16_IRQS(0x3)
-BUILD_16_IRQS(0x4) BUILD_16_IRQS(0x5) BUILD_16_IRQS(0x6) BUILD_16_IRQS(0x7)
-BUILD_16_IRQS(0x8) BUILD_16_IRQS(0x9) BUILD_16_IRQS(0xa) BUILD_16_IRQS(0xb)
-BUILD_16_IRQS(0xc) BUILD_16_IRQS(0xd)
-#endif
-
-#undef BUILD_16_IRQS
-#undef BI
-
-
-/*
- * The following vectors are part of the Linux architecture, there
- * is no hardware IRQ pin equivalent for them, they are triggered
- * through the ICC by us (IPIs)
- */
-#ifdef CONFIG_SMP
-BUILD_SMP_INTERRUPT(reschedule_interrupt,RESCHEDULE_VECTOR)
-BUILD_SMP_INTERRUPT(invalidate_interrupt,INVALIDATE_TLB_VECTOR)
-BUILD_SMP_INTERRUPT(call_function_interrupt,CALL_FUNCTION_VECTOR)
-#endif
-
-/*
- * every pentium local APIC has two 'local interrupts', with a
- * soft-definable vector attached to both interrupts, one of
- * which is a timer interrupt, the other one is error counter
- * overflow. Linux uses the local APIC timer interrupt to get
- * a much simpler SMP time architecture:
- */
-#ifdef CONFIG_X86_LOCAL_APIC
-BUILD_SMP_INTERRUPT(apic_timer_interrupt,LOCAL_TIMER_VECTOR)
-BUILD_SMP_INTERRUPT(error_interrupt,ERROR_APIC_VECTOR)
-BUILD_SMP_INTERRUPT(spurious_interrupt,SPURIOUS_APIC_VECTOR)
-#endif
-
-#define IRQ(x,y) \
- IRQ##x##y##_interrupt
-
-#define IRQLIST_16(x) \
- IRQ(x,0), IRQ(x,1), IRQ(x,2), IRQ(x,3), \
- IRQ(x,4), IRQ(x,5), IRQ(x,6), IRQ(x,7), \
- IRQ(x,8), IRQ(x,9), IRQ(x,a), IRQ(x,b), \
- IRQ(x,c), IRQ(x,d), IRQ(x,e), IRQ(x,f)
-
-void (*interrupt[NR_IRQS])(void) = {
- IRQLIST_16(0x0),
-
-#ifdef CONFIG_X86_IO_APIC
- IRQLIST_16(0x1), IRQLIST_16(0x2), IRQLIST_16(0x3),
- IRQLIST_16(0x4), IRQLIST_16(0x5), IRQLIST_16(0x6), IRQLIST_16(0x7),
- IRQLIST_16(0x8), IRQLIST_16(0x9), IRQLIST_16(0xa), IRQLIST_16(0xb),
- IRQLIST_16(0xc), IRQLIST_16(0xd)
-#endif
-};
-
-#undef IRQ
-#undef IRQLIST_16
-
-/*
* This is the 'legacy' 8259A Programmable Interrupt Controller,
* present in the majority of PC/AT boxes.
* plus some generic x86 specific things if generic specifics makes
diff -urN linux-2.5.8-pre2/arch/i386/kernel/io_apic.c linux/arch/i386/kernel/io_apic.c
--- linux-2.5.8-pre2/arch/i386/kernel/io_apic.c Thu Mar 7 21:18:23 2002
+++ linux/arch/i386/kernel/io_apic.c Sat Apr 6 11:48:15 2002
@@ -597,7 +597,6 @@
return current_vector;
}
-extern void (*interrupt[NR_IRQS])(void);
static struct hw_interrupt_type ioapic_level_irq_type;
static struct hw_interrupt_type ioapic_edge_irq_type;
diff -urN linux-2.5.8-pre2/include/asm-i386/hw_irq.h linux/include/asm-i386/hw_irq.h
--- linux-2.5.8-pre2/include/asm-i386/hw_irq.h Sat Apr 6 11:47:54 2002
+++ linux/include/asm-i386/hw_irq.h Sat Apr 6 13:06:17 2002
@@ -17,57 +17,28 @@
#include <asm/irq.h>
/*
- * IDT vectors usable for external interrupt sources start
- * at 0x20:
- */
-#define FIRST_EXTERNAL_VECTOR 0x20
-
-#define SYSCALL_VECTOR 0x80
-
-/*
- * Vectors 0x20-0x2f are used for ISA interrupts.
- */
-
-/*
- * Special IRQ vectors used by the SMP architecture, 0xf0-0xff
- *
- * some of the following vectors are 'rare', they are merged
- * into a single vector (CALL_FUNCTION_VECTOR) to save vector space.
- * TLB, reschedule and local APIC vectors are performance-critical.
+ * Various low-level irq details needed by irq.c, process.c,
+ * time.c, io_apic.c and smp.c
*
- * Vectors 0xf0-0xfa are free (reserved for future Linux use).
- */
-#define SPURIOUS_APIC_VECTOR 0xff
-#define ERROR_APIC_VECTOR 0xfe
-#define INVALIDATE_TLB_VECTOR 0xfd
-#define RESCHEDULE_VECTOR 0xfc
-#define CALL_FUNCTION_VECTOR 0xfb
-
-#define THERMAL_APIC_VECTOR 0xf0
-/*
- * Local APIC timer IRQ vector is on a different priority level,
- * to work around the 'lost local interrupt if more than 2 IRQ
- * sources per level' errata.
- */
-#define LOCAL_TIMER_VECTOR 0xef
-
-/*
- * First APIC vector available to drivers: (vectors 0x30-0xee)
- * we start at 0x31 to spread out vectors evenly between priority
- * levels. (0x80 is the syscall vector)
+ * Interrupt entry/exit code at both C and assembly level
*/
-#define FIRST_DEVICE_VECTOR 0x31
-#define FIRST_SYSTEM_VECTOR 0xef
extern int irq_vector[NR_IRQS];
#define IO_APIC_VECTOR(irq) irq_vector[irq]
-/*
- * Various low-level irq details needed by irq.c, process.c,
- * time.c, io_apic.c and smp.c
- *
- * Interrupt entry/exit code at both C and assembly level
- */
+extern void (*interrupt[NR_IRQS])(void);
+
+#ifdef CONFIG_SMP
+extern asmlinkage void reschedule_interrupt(void);
+extern asmlinkage void invalidate_interrupt(void);
+extern asmlinkage void call_function_interrupt(void);
+#endif
+
+#ifdef CONFIG_X86_LOCAL_APIC
+extern asmlinkage void apic_timer_interrupt(void);
+extern asmlinkage void error_interrupt(void);
+extern asmlinkage void spurious_interrupt(void);
+#endif
extern void mask_irq(unsigned int irq);
extern void unmask_irq(unsigned int irq);
@@ -93,92 +64,6 @@
#define IO_APIC_IRQ(x) (((x) >= 16) || ((1<<(x)) & io_apic_irqs))
-#define __STR(x) #x
-#define STR(x) __STR(x)
-
-#define GET_THREAD_INFO \
- "movl $-8192, %ebx\n\t" \
- "andl %esp, %ebx\n\t"
-
-#ifdef CONFIG_PREEMPT
-#define BUMP_LOCK_COUNT \
- GET_THREAD_INFO \
- "incl 16(%ebx)\n\t"
-#else
-#define BUMP_LOCK_COUNT
-#endif
-
-#define SAVE_ALL \
- "cld\n\t" \
- "pushl %es\n\t" \
- "pushl %ds\n\t" \
- "pushl %eax\n\t" \
- "pushl %ebp\n\t" \
- "pushl %edi\n\t" \
- "pushl %esi\n\t" \
- "pushl %edx\n\t" \
- "pushl %ecx\n\t" \
- "pushl %ebx\n\t" \
- "movl $" STR(__KERNEL_DS) ",%edx\n\t" \
- "movl %edx,%ds\n\t" \
- "movl %edx,%es\n\t" \
- BUMP_LOCK_COUNT
-
-#define IRQ_NAME2(nr) nr##_interrupt(void)
-#define IRQ_NAME(nr) IRQ_NAME2(IRQ##nr)
-
-#define GET_CURRENT \
- "movl %esp, %ebx\n\t" \
- "andl $-8192, %ebx\n\t" \
- "movl (%ebx),%ebx\n\t"
-
-/*
- * SMP has a few special interrupts for IPI messages
- */
-
- /* there is a second layer of macro just to get the symbolic
- name for the vector evaluated. This change is for RTLinux */
-#define BUILD_SMP_INTERRUPT(x,v) XBUILD_SMP_INTERRUPT(x,v)
-#define XBUILD_SMP_INTERRUPT(x,v)\
-asmlinkage void x(void); \
-asmlinkage void call_##x(void); \
-__asm__( \
-"\n"__ALIGN_STR"\n" \
-SYMBOL_NAME_STR(x) ":\n\t" \
- "pushl $"#v"-256\n\t" \
- SAVE_ALL \
- SYMBOL_NAME_STR(call_##x)":\n\t" \
- "call "SYMBOL_NAME_STR(smp_##x)"\n\t" \
- "jmp ret_from_intr\n");
-
-#define BUILD_COMMON_IRQ() \
-asmlinkage void call_do_IRQ(void); \
-__asm__( \
- "\n" __ALIGN_STR"\n" \
- "common_interrupt:\n\t" \
- SAVE_ALL \
- SYMBOL_NAME_STR(call_do_IRQ)":\n\t" \
- "call " SYMBOL_NAME_STR(do_IRQ) "\n\t" \
- "jmp ret_from_intr\n");
-
-/*
- * subtle. orig_eax is used by the signal code to distinct between
- * system calls and interrupted 'random user-space'. Thus we have
- * to put a negative value into orig_eax here. (the problem is that
- * both system calls and IRQs want to have small integer numbers in
- * orig_eax, and the syscall code has won the optimization conflict ;)
- *
- * Subtle as a pigs ear. VY
- */
-
-#define BUILD_IRQ(nr) \
-asmlinkage void IRQ_NAME(nr); \
-__asm__( \
-"\n"__ALIGN_STR"\n" \
-SYMBOL_NAME_STR(IRQ) #nr "_interrupt:\n\t" \
- "pushl $"#nr"-256\n\t" \
- "jmp common_interrupt");
-
extern unsigned long prof_cpu_mask;
extern unsigned int * prof_buffer;
extern unsigned long prof_len;
diff -urN linux-2.5.8-pre2/include/asm-i386/irq.h linux/include/asm-i386/irq.h
--- linux-2.5.8-pre2/include/asm-i386/irq.h Sat Apr 6 11:47:54 2002
+++ linux/include/asm-i386/irq.h Sat Apr 6 13:06:17 2002
@@ -12,23 +12,7 @@
#include <linux/config.h>
#include <linux/sched.h>
-
-#define TIMER_IRQ 0
-
-/*
- * 16 8259A IRQ's, 208 potential APIC interrupt sources.
- * Right now the APIC is mostly only used for SMP.
- * 256 vectors is an architectural limit. (we can have
- * more than 256 devices theoretically, but they will
- * have to use shared interrupts)
- * Since vectors 0x00-0x1f are used/reserved for the CPU,
- * the usable vector space is 0x20-0xff (224 vectors)
- */
-#ifdef CONFIG_X86_IO_APIC
-#define NR_IRQS 224
-#else
-#define NR_IRQS 16
-#endif
+#include <asm/irq_vectors.h>
static __inline__ int irq_cannonicalize(int irq)
{
diff -urN linux-2.5.8-pre2/include/asm-i386/irq_vectors.h linux/include/asm-i386/irq_vectors.h
--- linux-2.5.8-pre2/include/asm-i386/irq_vectors.h Wed Dec 31 19:00:00 1969
+++ linux/include/asm-i386/irq_vectors.h Sat Apr 6 13:06:17 2002
@@ -0,0 +1,64 @@
+#ifndef _ASM_IRQ_VECTORS_H
+#define _ASM_IRQ_VECTORS_H
+
+/*
+ * IDT vectors usable for external interrupt sources start
+ * at 0x20:
+ */
+#define FIRST_EXTERNAL_VECTOR 0x20
+
+#define SYSCALL_VECTOR 0x80
+
+/*
+ * Vectors 0x20-0x2f are used for ISA interrupts.
+ */
+
+/*
+ * Special IRQ vectors used by the SMP architecture, 0xf0-0xff
+ *
+ * some of the following vectors are 'rare', they are merged
+ * into a single vector (CALL_FUNCTION_VECTOR) to save vector space.
+ * TLB, reschedule and local APIC vectors are performance-critical.
+ *
+ * Vectors 0xf0-0xfa are free (reserved for future Linux use).
+ */
+#define SPURIOUS_APIC_VECTOR 0xff
+#define ERROR_APIC_VECTOR 0xfe
+#define INVALIDATE_TLB_VECTOR 0xfd
+#define RESCHEDULE_VECTOR 0xfc
+#define CALL_FUNCTION_VECTOR 0xfb
+
+#define THERMAL_APIC_VECTOR 0xf0
+/*
+ * Local APIC timer IRQ vector is on a different priority level,
+ * to work around the 'lost local interrupt if more than 2 IRQ
+ * sources per level' errata.
+ */
+#define LOCAL_TIMER_VECTOR 0xef
+
+/*
+ * First APIC vector available to drivers: (vectors 0x30-0xee)
+ * we start at 0x31 to spread out vectors evenly between priority
+ * levels. (0x80 is the syscall vector)
+ */
+#define FIRST_DEVICE_VECTOR 0x31
+#define FIRST_SYSTEM_VECTOR 0xef
+
+#define TIMER_IRQ 0
+
+/*
+ * 16 8259A IRQ's, 208 potential APIC interrupt sources.
+ * Right now the APIC is mostly only used for SMP.
+ * 256 vectors is an architectural limit. (we can have
+ * more than 256 devices theoretically, but they will
+ * have to use shared interrupts)
+ * Since vectors 0x00-0x1f are used/reserved for the CPU,
+ * the usable vector space is 0x20-0xff (224 vectors)
+ */
+#ifdef CONFIG_X86_IO_APIC
+#define NR_IRQS 224
+#else
+#define NR_IRQS 16
+#endif
+
+#endif /* _ASM_IRQ_VECTORS_H */
On Sat, 2002-04-06 at 15:03, Brian Gerst wrote:
> -ENTRY(ret_from_intr)
> - GET_THREAD_INFO(%ebx)
> - init_ret_intr
> +ret_from_intr:
> + preempt_stop
> + DEC_PRE_COUNT(%ebx)
You removed GET_THREAD_INFO and there does not seem to be a
replacement. Is there some assurance *thread_info is now pointed to by
%ebx here?
Robert Love
Robert Love wrote:
> On Sat, 2002-04-06 at 15:03, Brian Gerst wrote:
>
>
>>-ENTRY(ret_from_intr)
>>- GET_THREAD_INFO(%ebx)
>>- init_ret_intr
>>+ret_from_intr:
>>+ preempt_stop
>>+ DEC_PRE_COUNT(%ebx)
>
>
> You removed GET_THREAD_INFO and there does not seem to be a
> replacement. Is there some assurance *thread_info is now pointed to by
> %ebx here?
>
> Robert Love
>
Yes. It is set before the INC_PRE_COUNT and since it is preserved by
called functions it is still set when it gets to ret_from_intr.
--
Brian Gerst
On 6 Apr 2002, Robert Love wrote:
>
> You removed GET_THREAD_INFO and there does not seem to be a
> replacement. Is there some assurance *thread_info is now pointed to by
> %ebx here?
It seems to be always loaded by the common interrupt code (and %ebx is a
call-saved register, so calling the interrupt handlers and returning
doesn't clobber it).
But testing it may be a good idea ;^p
Linus
On Sat, 2002-04-06 at 15:18, Linus Torvalds wrote:
> It seems to be always loaded by the common interrupt code (and %ebx is a
> call-saved register, so calling the interrupt handlers and returning
> doesn't clobber it).
True enough. I guess I should of done this from the beginning ...
> But testing it may be a good idea ;^p
Of course I will, but it is hard (and subject to Heisenberg principals)
to test that we preempt whenever necessary. Only with the patch I sent
you earlier am I seeing no missed preemptions ... now to work on the
egregiously long-held locks.
Robert Love