1018.kernel-preempt.patch

sm86xx内核源包括补丁（ GPL ）的

 	kstat.irqs[cpu][irq]++;
 	spin_lock(&desc->lock);
 	desc->handler->ack(irq);
@@ -458,6 +464,7 @@
 	   will take care of it.
 	 */
 	if (!action) {
+ 		printk(KERN_ERR "spurious interrupt detected: %d\n", irq);
 		desc->handler->shutdown(irq); /* Shut off this IRQ */
 		goto out;
 	}
@@ -494,6 +501,27 @@
 
 	if (softirq_pending(cpu))
 		do_softirq();
+
+#if defined(CONFIG_PREEMPT)
+	while (--current->preempt_count == 0) {
+		db_assert(intr_off());
+		db_assert(!in_interrupt());
+
+		if (current->need_resched == 0) {
+			break;
+		}
+
+		current->preempt_count ++;
+		sti();
+		if (user_mode(regs)) {
+			schedule();
+		} else {
+			preempt_schedule();
+		}
+		cli();
+	}
+#endif
+
 	return 1;
 }
 
diff -Naur --exclude=CVS --exclude='*.o' --exclude='*.a' --exclude='*.so' --exclude='*.elf' --exclude=System.map --exclude=Makefile.d --exclude='*log' --exclude='*log2' --exclude='*~' --exclude='.*~' --exclude='.#*' --exclude='*.bak' --exclude='*.orig' --exclude='*.rej' --exclude='core.[0-9]*' --exclude=.depend --exclude='.*.o.flags' --exclude='*.gz' --exclude=.depend --exclude='.*.o.flags' --exclude='*.gz' --exclude=vmlinux --exclude=vmlinux.bin --exclude=yamon-02.06-SIGMADESIGNS-01_el.bin linuxmips-2.4.30.ref/arch/mips/mm/extable.c linuxmips-2.4.30/arch/mips/mm/extable.c
--- linuxmips-2.4.30.ref/arch/mips/mm/extable.c	2005-08-29 11:42:15.000000000 -0700
+++ linuxmips-2.4.30/arch/mips/mm/extable.c	2005-08-29 11:43:45.000000000 -0700
@@ -3,6 +3,7 @@
  */
 #include <linux/config.h>
 #include <linux/module.h>
+#include <linux/sched.h>
 #include <linux/spinlock.h>
 #include <asm/uaccess.h>
 
diff -Naur --exclude=CVS --exclude='*.o' --exclude='*.a' --exclude='*.so' --exclude='*.elf' --exclude=System.map --exclude=Makefile.d --exclude='*log' --exclude='*log2' --exclude='*~' --exclude='.*~' --exclude='.#*' --exclude='*.bak' --exclude='*.orig' --exclude='*.rej' --exclude='core.[0-9]*' --exclude=.depend --exclude='.*.o.flags' --exclude='*.gz' --exclude=.depend --exclude='.*.o.flags' --exclude='*.gz' --exclude=vmlinux --exclude=vmlinux.bin --exclude=yamon-02.06-SIGMADESIGNS-01_el.bin linuxmips-2.4.30.ref/arch/ppc/config.in linuxmips-2.4.30/arch/ppc/config.in
--- linuxmips-2.4.30.ref/arch/ppc/config.in	2005-08-29 11:42:15.000000000 -0700
+++ linuxmips-2.4.30/arch/ppc/config.in	2005-08-29 11:43:45.000000000 -0700
@@ -167,6 +167,8 @@
   int  'Maximum number of CPUs (2-32)' CONFIG_NR_CPUS 32
 fi
 
+bool 'Preemptible kernel support' CONFIG_PREEMPT
+
 if [ "$CONFIG_6xx" = "y" -a "$CONFIG_8260" = "n" ];then
   bool 'AltiVec Support' CONFIG_ALTIVEC
   bool 'Thermal Management Support' CONFIG_TAU
diff -Naur --exclude=CVS --exclude='*.o' --exclude='*.a' --exclude='*.so' --exclude='*.elf' --exclude=System.map --exclude=Makefile.d --exclude='*log' --exclude='*log2' --exclude='*~' --exclude='.*~' --exclude='.#*' --exclude='*.bak' --exclude='*.orig' --exclude='*.rej' --exclude='core.[0-9]*' --exclude=.depend --exclude='.*.o.flags' --exclude='*.gz' --exclude=.depend --exclude='.*.o.flags' --exclude='*.gz' --exclude=vmlinux --exclude=vmlinux.bin --exclude=yamon-02.06-SIGMADESIGNS-01_el.bin linuxmips-2.4.30.ref/arch/ppc/kernel/entry.S linuxmips-2.4.30/arch/ppc/kernel/entry.S
--- linuxmips-2.4.30.ref/arch/ppc/kernel/entry.S	2005-08-29 11:42:15.000000000 -0700
+++ linuxmips-2.4.30/arch/ppc/kernel/entry.S	2005-08-29 11:43:45.000000000 -0700
@@ -287,6 +287,46 @@
 	 */
 	cmpi	0,r3,0
 	beq	restore
+#ifdef CONFIG_PREEMPT
+	lwz	r3,PREEMPT_COUNT(r2)
+	cmpi	0,r3,1
+	bge	ret_from_except
+	lwz	r5,_MSR(r1)
+	andi.	r5,r5,MSR_PR
+	bne	do_signal_ret
+	lwz	r5,NEED_RESCHED(r2)
+	cmpi	0,r5,0
+	beq	ret_from_except
+	lis	r3,irq_stat@h
+	ori	r3,r3,irq_stat@l
+#ifdef CONFIG_SMP
+	lwz     r5,CPU(r2)
+	rlwinm  r5,r5,5,0,26
+	add     r3,r3,r5
+#endif
+	lwz	r5,4(r3)
+	lwz	r3,8(r3)
+	add	r3,r3,r5
+	cmpi	0,r3,0
+	bne	ret_from_except
+	lwz	r3,PREEMPT_COUNT(r2)
+	addi	r3,r3,1
+	stw	r3,PREEMPT_COUNT(r2)
+	mfmsr	r0
+	ori	r0,r0,MSR_EE
+	mtmsr	r0
+	sync
+	bl	preempt_schedule
+	mfmsr	r0
+	rlwinm	r0,r0,0,17,15
+	mtmsr	r0
+	sync
+	lwz	r3,PREEMPT_COUNT(r2)
+	subi	r3,r3,1
+	stw	r3,PREEMPT_COUNT(r2)
+	li	r3,1
+	b	ret_from_intercept
+#endif /* CONFIG_PREEMPT */
 	.globl	ret_from_except
 ret_from_except:
 	lwz	r3,_MSR(r1)	/* Returning to user mode? */
diff -Naur --exclude=CVS --exclude='*.o' --exclude='*.a' --exclude='*.so' --exclude='*.elf' --exclude=System.map --exclude=Makefile.d --exclude='*log' --exclude='*log2' --exclude='*~' --exclude='.*~' --exclude='.#*' --exclude='*.bak' --exclude='*.orig' --exclude='*.rej' --exclude='core.[0-9]*' --exclude=.depend --exclude='.*.o.flags' --exclude='*.gz' --exclude=.depend --exclude='.*.o.flags' --exclude='*.gz' --exclude=vmlinux --exclude=vmlinux.bin --exclude=yamon-02.06-SIGMADESIGNS-01_el.bin linuxmips-2.4.30.ref/arch/ppc/kernel/irq.c linuxmips-2.4.30/arch/ppc/kernel/irq.c
--- linuxmips-2.4.30.ref/arch/ppc/kernel/irq.c	2005-08-29 11:42:15.000000000 -0700
+++ linuxmips-2.4.30/arch/ppc/kernel/irq.c	2005-08-29 11:43:45.000000000 -0700
@@ -551,6 +551,34 @@
 	return 1; /* lets ret_from_int know we can do checks */
 }
 
+#ifdef CONFIG_PREEMPT
+int
+preempt_intercept(struct pt_regs *regs)
+{
+	int ret;
+
+	preempt_disable();
+
+	switch(regs->trap) {
+	case 0x500:
+		ret = do_IRQ(regs);
+		break;
+#ifndef CONFIG_4xx
+	case 0x900:
+#else
+	case 0x1000:
+#endif
+		ret = timer_interrupt(regs);
+		break;
+	default:
+		BUG();
+	}
+
+	preempt_enable();
+	return ret;
+}
+#endif /* CONFIG_PREEMPT */
+
 unsigned long probe_irq_on (void)
 {
 	return 0;
@@ -647,11 +675,13 @@
 				show("wait_on_irq");
 				count = ~0;
 			}
+			preempt_disable();
 			__sti();
 			/* don't worry about the lock race Linus found
 			 * on intel here. -- Cort
 			 */
 			__cli();
+			preempt_enable_no_resched();
 			if (atomic_read(&global_irq_count))
 				continue;
 			if (global_irq_lock)
@@ -727,6 +757,8 @@
 	global_irq_holder = cpu;
 }
 
+#define	EFLAGS_IF_SHIFT	15
+
 /*
  * A global "cli()" while in an interrupt context
  * turns into just a local cli(). Interrupts
@@ -744,9 +776,10 @@
 	unsigned long flags;
 
 	__save_flags(flags);
-	if (flags & (1 << 15)) {
-		int cpu = smp_processor_id();
+	if (flags & (1 << EFLAGS_IF_SHIFT)) {
+		int cpu;
 		__cli();
+		cpu = smp_processor_id();
 		if (!local_irq_count(cpu))
 			get_irqlock(cpu);
 	}
@@ -754,11 +787,14 @@
 
 void __global_sti(void)
 {
-	int cpu = smp_processor_id();
+	int cpu;
 
+	preempt_disable();
+	cpu = smp_processor_id();
 	if (!local_irq_count(cpu))
 		release_irqlock(cpu);
 	__sti();
+	preempt_enable();
 }
 
 /*
@@ -773,19 +809,23 @@
 	int retval;
 	int local_enabled;
 	unsigned long flags;
+	int cpu;
 
 	__save_flags(flags);
-	local_enabled = (flags >> 15) & 1;
+	local_enabled = (flags >> EFLAGS_IF_SHIFT) & 1;
 	/* default to local */
 	retval = 2 + local_enabled;
 
 	/* check for global flags if we're not in an interrupt */
-	if (!local_irq_count(smp_processor_id())) {
+	preempt_disable();
+	cpu = smp_processor_id();
+	if (!local_irq_count(cpu)) {
 		if (local_enabled)
 			retval = 1;
-		if (global_irq_holder == (unsigned char) smp_processor_id())
+		if (global_irq_holder == cpu)
 			retval = 0;
 	}
+	preempt_enable();
 	return retval;
 }
 
diff -Naur --exclude=CVS --exclude='*.o' --exclude='*.a' --exclude='*.so' --exclude='*.elf' --exclude=System.map --exclude=Makefile.d --exclude='*log' --exclude='*log2' --exclude='*~' --exclude='.*~' --exclude='.#*' --exclude='*.bak' --exclude='*.orig' --exclude='*.rej' --exclude='core.[0-9]*' --exclude=.depend --exclude='.*.o.flags' --exclude='*.gz' --exclude=.depend --exclude='.*.o.flags' --exclude='*.gz' --exclude=vmlinux --exclude=vmlinux.bin --exclude=yamon-02.06-SIGMADESIGNS-01_el.bin linuxmips-2.4.30.ref/arch/ppc/kernel/mk_defs.c linuxmips-2.4.30/arch/ppc/kernel/mk_defs.c
--- linuxmips-2.4.30.ref/arch/ppc/kernel/mk_defs.c	2005-08-29 11:42:15.000000000 -0700
+++ linuxmips-2.4.30/arch/ppc/kernel/mk_defs.c	2005-08-29 11:43:45.000000000 -0700
@@ -39,6 +39,9 @@
 	DEFINE(SIGPENDING, offsetof(struct task_struct, sigpending));
 	DEFINE(THREAD, offsetof(struct task_struct, thread));
 	DEFINE(MM, offsetof(struct task_struct, mm));
+#ifdef CONFIG_PREEMPT
+	DEFINE(PREEMPT_COUNT, offsetof(struct task_struct, preempt_count));
+#endif
 	DEFINE(ACTIVE_MM, offsetof(struct task_struct, active_mm));
 	DEFINE(TASK_STRUCT_SIZE, sizeof(struct task_struct));
 	DEFINE(KSP, offsetof(struct thread_struct, ksp));
diff -Naur --exclude=CVS --exclude='*.o' --exclude='*.a' --exclude='*.so' --exclude='*.elf' --exclude=System.map --exclude=Makefile.d --exclude='*log' --exclude='*log2' --exclude='*~' --exclude='.*~' --exclude='.#*' --exclude='*.bak' --exclude='*.orig' --exclude='*.rej' --exclude='core.[0-9]*' --exclude=.depend --exclude='.*.o.flags' --exclude='*.gz' --exclude=.depend --exclude='.*.o.flags' --exclude='*.gz' --exclude=vmlinux --exclude=vmlinux.bin --exclude=yamon-02.06-SIGMADESIGNS-01_el.bin linuxmips-2.4.30.ref/arch/ppc/kernel/open_pic.c linuxmips-2.4.30/arch/ppc/kernel/open_pic.c
--- linuxmips-2.4.30.ref/arch/ppc/kernel/open_pic.c	2005-08-29 11:42:15.000000000 -0700
+++ linuxmips-2.4.30/arch/ppc/kernel/open_pic.c	2005-08-29 11:43:45.000000000 -0700
@@ -601,19 +601,24 @@
 void __init do_openpic_setup_cpu(void)
 {
  	int i;
-	u32 msk = 1 << smp_hw_index[smp_processor_id()];
+#ifdef CONFIG_IRQ_ALL_CPUS
+	u32 msk;
+#endif /* CONFIG_IRQ_ALL_CPUS */
 
 	spin_lock(&openpic_setup_lock);
 
 #ifdef CONFIG_IRQ_ALL_CPUS
+	msk = 1 << smp_hw_index[smp_processor_id()];
+
  	/* let the openpic know we want intrs. default affinity
  	 * is 0xffffffff until changed via /proc
  	 * That's how it's done on x86. If we want it differently, then
  	 * we should make sure we also change the default values of irq_affinity
  	 * in irq.c.
  	 */
- 	for (i = 0; i < NumSources; i++)
+ 	for (i = 0; i < NumSources; i++) {
 		openpic_mapirq(i, msk, ~0U);
+	}
 #endif /* CONFIG_IRQ_ALL_CPUS */
  	openpic_set_priority(0);
 
diff -Naur --exclude=CVS --exclude='*.o' --exclude='*.a' --exclude='*.so' --exclude='*.elf' --exclude=System.map --exclude=Makefile.d --exclude='*log' --exclude='*log2' --exclude='*~' --exclude='.*~' --exclude='.#*' --exclude='*.bak' --exclude='*.orig' --exclude='*.rej' --exclude='core.[0-9]*' --exclude=.depend --exclude='.*.o.flags' --exclude='*.gz' --exclude=.depend --exclude='.*.o.flags' --exclude='*.gz' --exclude=vmlinux --exclude=vmlinux.bin --exclude=yamon-02.06-SIGMADESIGNS-01_el.bin linuxmips-2.4.30.ref/arch/ppc/kernel/setup.c linuxmips-2.4.30/arch/ppc/kernel/setup.c
--- linuxmips-2.4.30.ref/arch/ppc/kernel/setup.c	2005-08-29 11:42:15.000000000 -0700
+++ linuxmips-2.4.30/arch/ppc/kernel/setup.c	2005-08-29 11:43:45.000000000 -0700
@@ -502,6 +502,20 @@
 	strcpy(cmd_line, CONFIG_CMDLINE);
 #endif /* CONFIG_CMDLINE */
 
+#ifdef CONFIG_PREEMPT
+	/* Override the irq routines for external & timer interrupts here,
+	 * as the MMU has only been minimally setup at this point and
+	 * there are no protections on page zero.
+	 */
+	{
+		extern int preempt_intercept(struct pt_regs *);
+	
+		do_IRQ_intercept = (unsigned long) &preempt_intercept;
+		timer_interrupt_intercept = (unsigned long) &preempt_intercept;
+
+	}
+#endif /* CONFIG_PREEMPT */
+
 	platform_init(r3, r4, r5, r6, r7);
 
 	if (ppc_md.progress)
diff -Naur --exclude=CVS --exclude='*.o' --exclude='*.a' --exclude='*.so' --exclude='*.elf' --exclude=System.map --exclude=Makefile.d --exclude='*log' --exclude='*log2' --exclude='*~' --exclude='.*~' --exclude='.#*' --exclude='*.bak' --exclude='*.orig' --exclude='*.rej' --exclude='core.[0-9]*' --exclude=.depend --exclude='.*.o.flags' --exclude='*.gz' --exclude=.depend --exclude='.*.o.flags' --exclude='*.gz' --exclude=vmlinux --exclude=vmlinux.bin --exclude=yamon-02.06-SIGMADESIGNS-01_el.bin linuxmips-2.4.30.ref/arch/ppc/kernel/temp.c linuxmips-2.4.30/arch/ppc/kernel/temp.c