From 403d8efc94cd02ae36e7db13c4edf1d06d7b7fac Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Mon, 5 May 2008 18:13:50 +0200 Subject: [PATCH] x86: irq_32 move 4kstacks code to one place Move the 4KSTACKS related code to one place. This allows to un#ifdef do_IRQ() and share the executed on stack for the stack overflow printk and the softirq call. Signed-off-by: Thomas Gleixner Signed-off-by: Ingo Molnar --- arch/x86/kernel/irq_32.c | 191 +++++++++++++++++++-------------------- 1 file changed, 91 insertions(+), 100 deletions(-) diff --git a/arch/x86/kernel/irq_32.c b/arch/x86/kernel/irq_32.c index 1c470d2e5af7..4e3e8ec60276 100644 --- a/arch/x86/kernel/irq_32.c +++ b/arch/x86/kernel/irq_32.c @@ -83,26 +83,28 @@ union irq_ctx { static union irq_ctx *hardirq_ctx[NR_CPUS] __read_mostly; static union irq_ctx *softirq_ctx[NR_CPUS] __read_mostly; -static inline void call_on_stack(void *func, void *stack, - unsigned long arg1, void *arg2) -{ - unsigned long bx; +static char softirq_stack[NR_CPUS * THREAD_SIZE] + __attribute__((__section__(".bss.page_aligned"))); - asm volatile( - " xchgl %%ebx,%%esp \n" - " call *%%edi \n" - " movl %%ebx,%%esp \n" - : "=a" (arg1), "=d" (arg2), "=b" (bx) - : "0" (arg1), "1" (arg2), "2" (stack), - "D" (func) - : "memory", "cc", "ecx"); +static char hardirq_stack[NR_CPUS * THREAD_SIZE] + __attribute__((__section__(".bss.page_aligned"))); + +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; + u32 *isp, arg1, arg2; curctx = (union irq_ctx *) current_thread_info(); irqctx = hardirq_ctx[smp_processor_id()]; @@ -130,13 +132,86 @@ execute_on_irq_stack(int overflow, struct irq_desc *desc, int irq) (curctx->tinfo.preempt_count & SOFTIRQ_MASK); if (unlikely(overflow)) - call_on_stack(print_stack_overflow, isp, 0, NULL); - - call_on_stack(desc->handle_irq, isp, irq, desc); + 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 (hardirq_ctx[cpu]) + return; + + irqctx = (union irq_ctx*) &hardirq_stack[cpu*THREAD_SIZE]; + 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); + + hardirq_ctx[cpu] = irqctx; + + irqctx = (union irq_ctx*) &softirq_stack[cpu*THREAD_SIZE]; + 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); + + softirq_ctx[cpu] = irqctx; + + printk(KERN_DEBUG "CPU %u irqstacks, hard=%p soft=%p\n", + cpu,hardirq_ctx[cpu],softirq_ctx[cpu]); +} + +void irq_ctx_exit(int 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 = softirq_ctx[smp_processor_id()]; + 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; } @@ -176,90 +251,6 @@ unsigned int do_IRQ(struct pt_regs *regs) return 1; } -#ifdef CONFIG_4KSTACKS - -static char softirq_stack[NR_CPUS * THREAD_SIZE] - __attribute__((__section__(".bss.page_aligned"))); - -static char hardirq_stack[NR_CPUS * THREAD_SIZE] - __attribute__((__section__(".bss.page_aligned"))); - -/* - * allocate per-cpu stacks for hardirq and for softirq processing - */ -void irq_ctx_init(int cpu) -{ - union irq_ctx *irqctx; - - if (hardirq_ctx[cpu]) - return; - - irqctx = (union irq_ctx*) &hardirq_stack[cpu*THREAD_SIZE]; - 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); - - hardirq_ctx[cpu] = irqctx; - - irqctx = (union irq_ctx*) &softirq_stack[cpu*THREAD_SIZE]; - 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); - - softirq_ctx[cpu] = irqctx; - - printk("CPU %u irqstacks, hard=%p soft=%p\n", - cpu,hardirq_ctx[cpu],softirq_ctx[cpu]); -} - -void irq_ctx_exit(int 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 = softirq_ctx[smp_processor_id()]; - 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)); - - asm volatile( - " xchgl %%ebx,%%esp \n" - " call __do_softirq \n" - " movl %%ebx,%%esp \n" - : "=b"(isp) - : "0"(isp) - : "memory", "cc", "edx", "ecx", "eax" - ); - /* - * Shouldnt happen, we returned above if in_interrupt(): - */ - WARN_ON_ONCE(softirq_count()); - } - - local_irq_restore(flags); -} -#endif - /* * Interrupt statistics: */