From: Suresh Siddha <suresh.b.siddha@intel.com>
Subject: x86: Unify fixup_irqs() for 32-bit and 64-bit kernels
References: bnc#558247
Patch-mainline: Yes
Commit 7a7732bc0f7c46f217dbec723f25366b6285cc42 upstream.
There is no reason to have different fixup_irqs() for 32-bit
and 64-bit kernels. Unify by using the superior 64-bit version for
both the kernels.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Gary Hade <garyhade@us.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Rafael J. Wysocki <rjw@suse.de>
Automatically created from "patches.arch/x86-Unify-fixup_irqs-for-32-bit-and-64-bit-kernels.patch" by xen-port-patches.py
--- sle11sp1-2010-01-27.orig/arch/x86/kernel/irq-xen.c 2009-12-18 09:59:05.000000000 +0100
+++ sle11sp1-2010-01-27/arch/x86/kernel/irq-xen.c 2010-01-07 10:30:58.000000000 +0100
@@ -286,3 +286,62 @@ void smp_generic_interrupt(struct pt_reg
set_irq_regs(old_regs);
}
#endif
+
+#ifdef CONFIG_HOTPLUG_CPU
+/* A cpu has been removed from cpu_online_mask. Reset irq affinities. */
+void fixup_irqs(void)
+{
+ unsigned int irq;
+ static int warned;
+ struct irq_desc *desc;
+
+ for_each_irq_desc(irq, desc) {
+ int break_affinity = 0;
+ int set_affinity = 1;
+ const struct cpumask *affinity;
+
+ if (!desc)
+ continue;
+ if (irq == 2)
+ continue;
+
+ /* interrupt's are disabled at this point */
+ spin_lock(&desc->lock);
+
+ affinity = desc->affinity;
+ if (!irq_has_action(irq) ||
+ cpumask_equal(affinity, cpu_online_mask)) {
+ spin_unlock(&desc->lock);
+ continue;
+ }
+
+ if (cpumask_any_and(affinity, cpu_online_mask) >= nr_cpu_ids) {
+ break_affinity = 1;
+ affinity = cpu_all_mask;
+ }
+
+ if (desc->chip->mask)
+ desc->chip->mask(irq);
+
+ if (desc->chip->set_affinity)
+ desc->chip->set_affinity(irq, affinity);
+ else if (!(warned++))
+ set_affinity = 0;
+
+ if (desc->chip->unmask)
+ desc->chip->unmask(irq);
+
+ spin_unlock(&desc->lock);
+
+ if (break_affinity && set_affinity)
+ /*printk("Broke affinity for irq %i\n", irq)*/;
+ else if (!set_affinity)
+ printk("Cannot set affinity for irq %i\n", irq);
+ }
+
+ /* That doesn't seem sufficient. Give it 1ms. */
+ local_irq_enable();
+ mdelay(1);
+ local_irq_disable();
+}
+#endif
--- sle11sp1-2010-01-27.orig/arch/x86/kernel/irq_32-xen.c 2009-11-06 10:52:22.000000000 +0100
+++ /dev/null 1970-01-01 00:00:00.000000000 +0000
@@ -1,258 +0,0 @@
-/*
- * Copyright (C) 1992, 1998 Linus Torvalds, Ingo Molnar
- *
- * This file contains the lowest level x86-specific interrupt
- * entry, irq-stacks and irq statistics code. All the remaining
- * irq logic is done by the generic kernel/irq/ code and
- * by the x86-specific irq controller code. (e.g. i8259.c and
- * io_apic.c.)
- */
-
-#include <linux/module.h>
-#include <linux/seq_file.h>
-#include <linux/interrupt.h>
-#include <linux/kernel_stat.h>
-#include <linux/notifier.h>
-#include <linux/cpu.h>
-#include <linux/delay.h>
-#include <linux/uaccess.h>
-#include <linux/percpu.h>
-
-#include <asm/apic.h>
-
-DEFINE_PER_CPU_SHARED_ALIGNED(irq_cpustat_t, irq_stat);
-EXPORT_PER_CPU_SYMBOL(irq_stat);
-
-DEFINE_PER_CPU(struct pt_regs *, irq_regs);
-EXPORT_PER_CPU_SYMBOL(irq_regs);
-
-#ifdef CONFIG_DEBUG_STACKOVERFLOW
-/* Debugging check for stack overflow: is there less than 1KB free? */
-static int check_stack_overflow(void)
-{
- long sp;
-
- __asm__ __volatile__("andl %%esp,%0" :
- "=r" (sp) : "0" (THREAD_SIZE - 1));
-
- return sp < (sizeof(struct thread_info) + STACK_WARN);
-}
-
-static void print_stack_overflow(void)
-{
- printk(KERN_WARNING "low stack detected by irq handler\n");
- dump_stack();
-}
-
-#else
-static inline int check_stack_overflow(void) { return 0; }
-static inline void print_stack_overflow(void) { }
-#endif
-
-#ifdef CONFIG_4KSTACKS
-/*
- * per-CPU IRQ handling contexts (thread information and stack)
- */
-union irq_ctx {
- struct thread_info tinfo;
- u32 stack[THREAD_SIZE/sizeof(u32)];
-} __attribute__((aligned(PAGE_SIZE)));
-
-static DEFINE_PER_CPU(union irq_ctx *, hardirq_ctx);
-static DEFINE_PER_CPU(union irq_ctx *, softirq_ctx);
-
-static DEFINE_PER_CPU_PAGE_ALIGNED(union irq_ctx, hardirq_stack);
-static DEFINE_PER_CPU_PAGE_ALIGNED(union irq_ctx, softirq_stack);
-
-static void call_on_stack(void *func, void *stack)
-{
- asm volatile("xchgl %%ebx,%%esp \n"
- "call *%%edi \n"
- "movl %%ebx,%%esp \n"
- : "=b" (stack)
- : "0" (stack),
- "D"(func)
- : "memory", "cc", "edx", "ecx", "eax");
-}
-
-static inline int
-execute_on_irq_stack(int overflow, struct irq_desc *desc, int irq)
-{
- union irq_ctx *curctx, *irqctx;
- u32 *isp, arg1, arg2;
-
- curctx = (union irq_ctx *) current_thread_info();
- irqctx = __get_cpu_var(hardirq_ctx);
-
- /*
- * this is where we switch to the IRQ stack. However, if we are
- * already using the IRQ stack (because we interrupted a hardirq
- * handler) we can't do that and just have to keep using the
- * current stack (which is the irq stack already after all)
- */
- if (unlikely(curctx == irqctx))
- return 0;
-
- /* build the stack frame on the IRQ stack */
- isp = (u32 *) ((char *)irqctx + sizeof(*irqctx));
- irqctx->tinfo.task = curctx->tinfo.task;
- irqctx->tinfo.previous_esp = current_stack_pointer;
-
- /*
- * Copy the softirq bits in preempt_count so that the
- * softirq checks work in the hardirq context.
- */
- irqctx->tinfo.preempt_count =
- (irqctx->tinfo.preempt_count & ~SOFTIRQ_MASK) |
- (curctx->tinfo.preempt_count & SOFTIRQ_MASK);
-
- if (unlikely(overflow))
- call_on_stack(print_stack_overflow, isp);
-
- asm volatile("xchgl %%ebx,%%esp \n"
- "call *%%edi \n"
- "movl %%ebx,%%esp \n"
- : "=a" (arg1), "=d" (arg2), "=b" (isp)
- : "0" (irq), "1" (desc), "2" (isp),
- "D" (desc->handle_irq)
- : "memory", "cc", "ecx");
- return 1;
-}
-
-/*
- * allocate per-cpu stacks for hardirq and for softirq processing
- */
-void __cpuinit irq_ctx_init(int cpu)
-{
- union irq_ctx *irqctx;
-
- if (per_cpu(hardirq_ctx, cpu))
- return;
-
- irqctx = &per_cpu(hardirq_stack, cpu);
- irqctx->tinfo.task = NULL;
- irqctx->tinfo.exec_domain = NULL;
- irqctx->tinfo.cpu = cpu;
- irqctx->tinfo.preempt_count = HARDIRQ_OFFSET;
- irqctx->tinfo.addr_limit = MAKE_MM_SEG(0);
-
- per_cpu(hardirq_ctx, cpu) = irqctx;
-
- irqctx = &per_cpu(softirq_stack, cpu);
- irqctx->tinfo.task = NULL;
- irqctx->tinfo.exec_domain = NULL;
- irqctx->tinfo.cpu = cpu;
- irqctx->tinfo.preempt_count = 0;
- irqctx->tinfo.addr_limit = MAKE_MM_SEG(0);
-
- per_cpu(softirq_ctx, cpu) = irqctx;
-
- printk(KERN_DEBUG "CPU %u irqstacks, hard=%p soft=%p\n",
- cpu, per_cpu(hardirq_ctx, cpu), per_cpu(softirq_ctx, cpu));
-}
-
-void irq_ctx_exit(int cpu)
-{
- per_cpu(hardirq_ctx, cpu) = NULL;
-}
-
-asmlinkage void do_softirq(void)
-{
- unsigned long flags;
- struct thread_info *curctx;
- union irq_ctx *irqctx;
- u32 *isp;
-
- if (in_interrupt())
- return;
-
- local_irq_save(flags);
-
- if (local_softirq_pending()) {
- curctx = current_thread_info();
- irqctx = __get_cpu_var(softirq_ctx);
- irqctx->tinfo.task = curctx->task;
- irqctx->tinfo.previous_esp = current_stack_pointer;
-
- /* build the stack frame on the softirq stack */
- isp = (u32 *) ((char *)irqctx + sizeof(*irqctx));
-
- call_on_stack(__do_softirq, isp);
- /*
- * Shouldnt happen, we returned above if in_interrupt():
- */
- WARN_ON_ONCE(softirq_count());
- }
-
- local_irq_restore(flags);
-}
-
-#else
-static inline int
-execute_on_irq_stack(int overflow, struct irq_desc *desc, int irq) { return 0; }
-#endif
-
-bool handle_irq(unsigned irq, struct pt_regs *regs)
-{
- struct irq_desc *desc;
- int overflow;
-
- overflow = check_stack_overflow();
-
- desc = irq_to_desc(irq);
- if (unlikely(!desc))
- return false;
-
- if (!execute_on_irq_stack(overflow, desc, irq)) {
- if (unlikely(overflow))
- print_stack_overflow();
- desc->handle_irq(irq, desc);
- }
-
- return true;
-}
-
-#ifdef CONFIG_HOTPLUG_CPU
-
-/* A cpu has been removed from cpu_online_mask. Reset irq affinities. */
-void fixup_irqs(void)
-{
- unsigned int irq;
- struct irq_desc *desc;
-
- for_each_irq_desc(irq, desc) {
- const struct cpumask *affinity;
-
- if (!desc)
- continue;
- if (irq == 2)
- continue;
-
- affinity = desc->affinity;
- if (cpumask_any_and(affinity, cpu_online_mask) >= nr_cpu_ids) {
- /*printk("Breaking affinity for irq %i\n", irq);*/
- affinity = cpu_all_mask;
- }
- if (desc->chip->set_affinity)
- desc->chip->set_affinity(irq, affinity);
- else if (desc->action)
- printk_once("Cannot set affinity for irq %i\n", irq);
- }
-
-#if 0
- barrier();
- /* Ingo Molnar says: "after the IO-APIC masks have been redirected
- [note the nop - the interrupt-enable boundary on x86 is two
- instructions from sti] - to flush out pending hardirqs and
- IPIs. After this point nothing is supposed to reach this CPU." */
- __asm__ __volatile__("sti; nop; cli");
- barrier();
-#else
- /* That doesn't seem sufficient. Give it 1ms. */
- local_irq_enable();
- mdelay(1);
- local_irq_disable();
-#endif
-}
-#endif
-
--- sle11sp1-2010-01-27.orig/arch/x86/kernel/irq_64-xen.c 2009-11-06 10:52:02.000000000 +0100
+++ /dev/null 1970-01-01 00:00:00.000000000 +0000
@@ -1,142 +0,0 @@
-/*
- * Copyright (C) 1992, 1998 Linus Torvalds, Ingo Molnar
- *
- * This file contains the lowest level x86_64-specific interrupt
- * entry and irq statistics code. All the remaining irq logic is
- * done by the generic kernel/irq/ code and in the
- * x86_64-specific irq controller code. (e.g. i8259.c and
- * io_apic.c.)
- */
-
-#include <linux/kernel_stat.h>
-#include <linux/interrupt.h>
-#include <linux/seq_file.h>
-#include <linux/module.h>
-#include <linux/delay.h>
-#include <linux/ftrace.h>
-#include <linux/uaccess.h>
-#include <linux/smp.h>
-#include <asm/io_apic.h>
-#include <asm/idle.h>
-#include <asm/apic.h>
-
-DEFINE_PER_CPU_SHARED_ALIGNED(irq_cpustat_t, irq_stat);
-EXPORT_PER_CPU_SYMBOL(irq_stat);
-
-DEFINE_PER_CPU(struct pt_regs *, irq_regs);
-EXPORT_PER_CPU_SYMBOL(irq_regs);
-
-/*
- * Probabilistic stack overflow check:
- *
- * Only check the stack in process context, because everything else
- * runs on the big interrupt stacks. Checking reliably is too expensive,
- * so we just check from interrupts.
- */
-static inline void stack_overflow_check(struct pt_regs *regs)
-{
-#ifdef CONFIG_DEBUG_STACKOVERFLOW
- u64 curbase = (u64)task_stack_page(current);
-
- WARN_ONCE(regs->sp >= curbase &&
- regs->sp <= curbase + THREAD_SIZE &&
- regs->sp < curbase + sizeof(struct thread_info) +
- sizeof(struct pt_regs) + 128,
-
- "do_IRQ: %s near stack overflow (cur:%Lx,sp:%lx)\n",
- current->comm, curbase, regs->sp);
-#endif
-}
-
-bool handle_irq(unsigned irq, struct pt_regs *regs)
-{
- struct irq_desc *desc;
-
- stack_overflow_check(regs);
-
- desc = irq_to_desc(irq);
- if (unlikely(!desc))
- return false;
-
- generic_handle_irq_desc(irq, desc);
- return true;
-}
-
-#ifdef CONFIG_HOTPLUG_CPU
-/* A cpu has been removed from cpu_online_mask. Reset irq affinities. */
-void fixup_irqs(void)
-{
- unsigned int irq;
- static int warned;
- struct irq_desc *desc;
-
- for_each_irq_desc(irq, desc) {
- int break_affinity = 0;
- int set_affinity = 1;
- const struct cpumask *affinity;
-
- if (!desc)
- continue;
- if (irq == 2)
- continue;
-
- /* interrupt's are disabled at this point */
- spin_lock(&desc->lock);
-
- affinity = desc->affinity;
- if (!irq_has_action(irq) ||
- cpumask_equal(affinity, cpu_online_mask)) {
- spin_unlock(&desc->lock);
- continue;
- }
-
- if (cpumask_any_and(affinity, cpu_online_mask) >= nr_cpu_ids) {
- break_affinity = 1;
- affinity = cpu_all_mask;
- }
-
- if (desc->chip->mask)
- desc->chip->mask(irq);
-
- if (desc->chip->set_affinity)
- desc->chip->set_affinity(irq, affinity);
- else if (!(warned++))
- set_affinity = 0;
-
- if (desc->chip->unmask)
- desc->chip->unmask(irq);
-
- spin_unlock(&desc->lock);
-
- if (break_affinity && set_affinity)
- /*printk("Broke affinity for irq %i\n", irq)*/;
- else if (!set_affinity)
- printk("Cannot set affinity for irq %i\n", irq);
- }
-
- /* That doesn't seem sufficient. Give it 1ms. */
- local_irq_enable();
- mdelay(1);
- local_irq_disable();
-}
-#endif
-
-extern void call_softirq(void);
-
-asmlinkage void do_softirq(void)
-{
- __u32 pending;
- unsigned long flags;
-
- if (in_interrupt())
- return;
-
- local_irq_save(flags);
- pending = local_softirq_pending();
- /* Switch to interrupt stack */
- if (pending) {
- call_softirq();
- WARN_ON_ONCE(softirq_count());
- }
- local_irq_restore(flags);
-}
