Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753520Ab3ISTvV (ORCPT ); Thu, 19 Sep 2013 15:51:21 -0400 Received: from mail-ob0-f173.google.com ([209.85.214.173]:34776 "EHLO mail-ob0-f173.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752071Ab3ISTvR (ORCPT ); Thu, 19 Sep 2013 15:51:17 -0400 From: Frederic Weisbecker To: Thomas Gleixner Cc: LKML , Frederic Weisbecker , Benjamin Herrenschmidt , Paul Mackerras , Ingo Molnar , Peter Zijlstra , "H. Peter Anvin" , Linus Torvalds , James Hogan , "James E.J. Bottomley" , Helge Deller , Martin Schwidefsky , Heiko Carstens , "David S. Miller" , Andrew Morton Subject: [PATCH 1/3] irq: Consolidate do_softirq() arch overriden implementations Date: Thu, 19 Sep 2013 14:51:05 -0500 Message-Id: <1379620267-25191-2-git-send-email-fweisbec@gmail.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1379620267-25191-1-git-send-email-fweisbec@gmail.com> References: <1379620267-25191-1-git-send-email-fweisbec@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 13940 Lines: 514 All arch overriden implementations of do_softirq() share the following common code: disable irqs, check if there are softirqs pending, then execute __do_softirq() on a specific stack. Consolidate the common parts such that archs only worry about the stack switch. Reported-by: Benjamin Herrenschmidt Signed-off-by: Frederic Weisbecker Tested-by: Paul Mackerras Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: Ingo Molnar Cc: Thomas Gleixner Cc: Peter Zijlstra Cc: H. Peter Anvin Cc: Linus Torvalds Cc: Paul Mackerras Cc: James Hogan Cc: James E.J. Bottomley Cc: Helge Deller Cc: Martin Schwidefsky Cc: Heiko Carstens Cc: David S. Miller Cc: Andrew Morton --- arch/metag/kernel/irq.c | 56 ++++++++++++++++++------------------------- arch/parisc/kernel/irq.c | 17 ++----------- arch/powerpc/kernel/irq.c | 17 +------------ arch/s390/kernel/irq.c | 52 ++++++++++++++++------------------------ arch/sh/kernel/irq.c | 60 +++++++++++++++++++--------------------------- arch/sparc/kernel/irq_64.c | 31 ++++++++---------------- arch/x86/kernel/irq_32.c | 34 ++++++++++---------------- arch/x86/kernel/irq_64.c | 18 +++----------- include/linux/interrupt.h | 11 +++++++++ kernel/softirq.c | 7 ++---- 10 files changed, 110 insertions(+), 193 deletions(-) diff --git a/arch/metag/kernel/irq.c b/arch/metag/kernel/irq.c index 2a2c9d5..12a12b4 100644 --- a/arch/metag/kernel/irq.c +++ b/arch/metag/kernel/irq.c @@ -159,44 +159,34 @@ void irq_ctx_exit(int cpu) extern asmlinkage void __do_softirq(void); -asmlinkage void do_softirq(void) +void do_softirq_own_stack(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; - - /* build the stack frame on the softirq stack */ - isp = (u32 *) ((char *)irqctx + sizeof(struct thread_info)); - - asm volatile ( - "MOV D0.5,%0\n" - "SWAP A0StP,D0.5\n" - "CALLR D1RtP,___do_softirq\n" - "MOV A0StP,D0.5\n" - : - : "r" (isp) - : "memory", "cc", "D1Ar1", "D0Ar2", "D1Ar3", "D0Ar4", - "D1Ar5", "D0Ar6", "D0Re0", "D1Re0", "D0.4", "D1RtP", - "D0.5" - ); - /* - * Shouldn't happen, we returned above if in_interrupt(): - */ - WARN_ON_ONCE(softirq_count()); - } - - local_irq_restore(flags); + curctx = current_thread_info(); + irqctx = softirq_ctx[smp_processor_id()]; + irqctx->tinfo.task = curctx->task; + + /* build the stack frame on the softirq stack */ + isp = (u32 *) ((char *)irqctx + sizeof(struct thread_info)); + + asm volatile ( + "MOV D0.5,%0\n" + "SWAP A0StP,D0.5\n" + "CALLR D1RtP,___do_softirq\n" + "MOV A0StP,D0.5\n" + : + : "r" (isp) + : "memory", "cc", "D1Ar1", "D0Ar2", "D1Ar3", "D0Ar4", + "D1Ar5", "D0Ar6", "D0Re0", "D1Re0", "D0.4", "D1RtP", + "D0.5" + ); + /* + * Shouldn't happen, we returned above if in_interrupt(): + */ + WARN_ON_ONCE(softirq_count()); } #endif diff --git a/arch/parisc/kernel/irq.c b/arch/parisc/kernel/irq.c index 2e6443b..ef59276 100644 --- a/arch/parisc/kernel/irq.c +++ b/arch/parisc/kernel/irq.c @@ -499,22 +499,9 @@ static void execute_on_irq_stack(void *func, unsigned long param1) *irq_stack_in_use = 1; } -asmlinkage void do_softirq(void) +void do_softirq_own_stack(void) { - __u32 pending; - unsigned long flags; - - if (in_interrupt()) - return; - - local_irq_save(flags); - - pending = local_softirq_pending(); - - if (pending) - execute_on_irq_stack(__do_softirq, 0); - - local_irq_restore(flags); + execute_on_irq_stack(__do_softirq, 0); } #endif /* CONFIG_IRQSTACKS */ diff --git a/arch/powerpc/kernel/irq.c b/arch/powerpc/kernel/irq.c index c69440c..7d0da88 100644 --- a/arch/powerpc/kernel/irq.c +++ b/arch/powerpc/kernel/irq.c @@ -601,7 +601,7 @@ void irq_ctx_init(void) } } -static inline void do_softirq_onstack(void) +void do_softirq_own_stack(void) { struct thread_info *curtp, *irqtp; unsigned long saved_sp_limit = current->thread.ksp_limit; @@ -623,21 +623,6 @@ static inline void do_softirq_onstack(void) set_bits(irqtp->flags, &curtp->flags); } -void do_softirq(void) -{ - unsigned long flags; - - if (in_interrupt()) - return; - - local_irq_save(flags); - - if (local_softirq_pending()) - do_softirq_onstack(); - - local_irq_restore(flags); -} - irq_hw_number_t virq_to_hw(unsigned int virq) { struct irq_data *irq_data = irq_get_irq_data(virq); diff --git a/arch/s390/kernel/irq.c b/arch/s390/kernel/irq.c index 8ac2097..bb27a26 100644 --- a/arch/s390/kernel/irq.c +++ b/arch/s390/kernel/irq.c @@ -157,39 +157,29 @@ int arch_show_interrupts(struct seq_file *p, int prec) /* * Switch to the asynchronous interrupt stack for softirq execution. */ -asmlinkage void do_softirq(void) +void do_softirq_own_stack(void) { - unsigned long flags, old, new; - - if (in_interrupt()) - return; - - local_irq_save(flags); - - if (local_softirq_pending()) { - /* Get current stack pointer. */ - asm volatile("la %0,0(15)" : "=a" (old)); - /* Check against async. stack address range. */ - new = S390_lowcore.async_stack; - if (((new - old) >> (PAGE_SHIFT + THREAD_ORDER)) != 0) { - /* Need to switch to the async. stack. */ - new -= STACK_FRAME_OVERHEAD; - ((struct stack_frame *) new)->back_chain = old; - - asm volatile(" la 15,0(%0)\n" - " basr 14,%2\n" - " la 15,0(%1)\n" - : : "a" (new), "a" (old), - "a" (__do_softirq) - : "0", "1", "2", "3", "4", "5", "14", - "cc", "memory" ); - } else { - /* We are already on the async stack. */ - __do_softirq(); - } + unsigned long old, new; + + /* Get current stack pointer. */ + asm volatile("la %0,0(15)" : "=a" (old)); + /* Check against async. stack address range. */ + new = S390_lowcore.async_stack; + if (((new - old) >> (PAGE_SHIFT + THREAD_ORDER)) != 0) { + /* Need to switch to the async. stack. */ + new -= STACK_FRAME_OVERHEAD; + ((struct stack_frame *) new)->back_chain = old; + asm volatile(" la 15,0(%0)\n" + " basr 14,%2\n" + " la 15,0(%1)\n" + : : "a" (new), "a" (old), + "a" (__do_softirq) + : "0", "1", "2", "3", "4", "5", "14", + "cc", "memory" ); + } else { + /* We are already on the async stack. */ + __do_softirq(); } - - local_irq_restore(flags); } /* diff --git a/arch/sh/kernel/irq.c b/arch/sh/kernel/irq.c index 063af10..50ecd48 100644 --- a/arch/sh/kernel/irq.c +++ b/arch/sh/kernel/irq.c @@ -149,47 +149,37 @@ void irq_ctx_exit(int cpu) hardirq_ctx[cpu] = NULL; } -asmlinkage void do_softirq(void) +void do_softirq_own_stack(void) { - unsigned long flags; struct thread_info *curctx; union irq_ctx *irqctx; u32 *isp; - if (in_interrupt()) - return; - - local_irq_save(flags); + curctx = current_thread_info(); + irqctx = softirq_ctx[smp_processor_id()]; + irqctx->tinfo.task = curctx->task; + irqctx->tinfo.previous_sp = current_stack_pointer; + + /* build the stack frame on the softirq stack */ + isp = (u32 *)((char *)irqctx + sizeof(*irqctx)); + + __asm__ __volatile__ ( + "mov r15, r9 \n" + "jsr @%0 \n" + /* switch to the softirq stack */ + " mov %1, r15 \n" + /* restore the thread stack */ + "mov r9, r15 \n" + : /* no outputs */ + : "r" (__do_softirq), "r" (isp) + : "memory", "r0", "r1", "r2", "r3", "r4", + "r5", "r6", "r7", "r8", "r9", "r15", "t", "pr" + ); - if (local_softirq_pending()) { - curctx = current_thread_info(); - irqctx = softirq_ctx[smp_processor_id()]; - irqctx->tinfo.task = curctx->task; - irqctx->tinfo.previous_sp = current_stack_pointer; - - /* build the stack frame on the softirq stack */ - isp = (u32 *)((char *)irqctx + sizeof(*irqctx)); - - __asm__ __volatile__ ( - "mov r15, r9 \n" - "jsr @%0 \n" - /* switch to the softirq stack */ - " mov %1, r15 \n" - /* restore the thread stack */ - "mov r9, r15 \n" - : /* no outputs */ - : "r" (__do_softirq), "r" (isp) - : "memory", "r0", "r1", "r2", "r3", "r4", - "r5", "r6", "r7", "r8", "r9", "r15", "t", "pr" - ); - - /* - * Shouldn't happen, we returned above if in_interrupt(): - */ - WARN_ON_ONCE(softirq_count()); - } - - local_irq_restore(flags); + /* + * Shouldn't happen, we returned above if in_interrupt(): + */ + WARN_ON_ONCE(softirq_count()); } #else static inline void handle_one_irq(unsigned int irq) diff --git a/arch/sparc/kernel/irq_64.c b/arch/sparc/kernel/irq_64.c index d4840ce..666193f 100644 --- a/arch/sparc/kernel/irq_64.c +++ b/arch/sparc/kernel/irq_64.c @@ -698,30 +698,19 @@ void __irq_entry handler_irq(int pil, struct pt_regs *regs) set_irq_regs(old_regs); } -void do_softirq(void) +void do_softirq_own_stack(void) { - unsigned long flags; - - if (in_interrupt()) - return; - - local_irq_save(flags); + void *orig_sp, *sp = softirq_stack[smp_processor_id()]; - if (local_softirq_pending()) { - void *orig_sp, *sp = softirq_stack[smp_processor_id()]; - - sp += THREAD_SIZE - 192 - STACK_BIAS; - - __asm__ __volatile__("mov %%sp, %0\n\t" - "mov %1, %%sp" - : "=&r" (orig_sp) - : "r" (sp)); - __do_softirq(); - __asm__ __volatile__("mov %0, %%sp" - : : "r" (orig_sp)); - } + sp += THREAD_SIZE - 192 - STACK_BIAS; - local_irq_restore(flags); + __asm__ __volatile__("mov %%sp, %0\n\t" + "mov %1, %%sp" + : "=&r" (orig_sp) + : "r" (sp)); + __do_softirq(); + __asm__ __volatile__("mov %0, %%sp" + : : "r" (orig_sp)); } #ifdef CONFIG_HOTPLUG_CPU diff --git a/arch/x86/kernel/irq_32.c b/arch/x86/kernel/irq_32.c index 4186755..1036f03 100644 --- a/arch/x86/kernel/irq_32.c +++ b/arch/x86/kernel/irq_32.c @@ -149,35 +149,25 @@ void irq_ctx_init(int cpu) cpu, per_cpu(hardirq_ctx, cpu), per_cpu(softirq_ctx, cpu)); } -asmlinkage void do_softirq(void) +void do_softirq_own_stack(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 = __this_cpu_read(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)); + curctx = current_thread_info(); + irqctx = __this_cpu_read(softirq_ctx); + irqctx->tinfo.task = curctx->task; + irqctx->tinfo.previous_esp = current_stack_pointer; - call_on_stack(__do_softirq, isp); - /* - * Shouldn't happen, we returned above if in_interrupt(): - */ - WARN_ON_ONCE(softirq_count()); - } + /* build the stack frame on the softirq stack */ + isp = (u32 *) ((char *)irqctx + sizeof(*irqctx)); - local_irq_restore(flags); + call_on_stack(__do_softirq, isp); + /* + * Shouldn't happen, we returned above if in_interrupt(): + */ + WARN_ON_ONCE(softirq_count()); } bool handle_irq(unsigned irq, struct pt_regs *regs) diff --git a/arch/x86/kernel/irq_64.c b/arch/x86/kernel/irq_64.c index d04d3ec..8dd8c96 100644 --- a/arch/x86/kernel/irq_64.c +++ b/arch/x86/kernel/irq_64.c @@ -91,20 +91,8 @@ bool handle_irq(unsigned irq, struct pt_regs *regs) extern void call_softirq(void); -asmlinkage void do_softirq(void) +void do_softirq_own_stack(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); + call_softirq(); + WARN_ON_ONCE(softirq_count()); } diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h index 5e865b5..c9e831d 100644 --- a/include/linux/interrupt.h +++ b/include/linux/interrupt.h @@ -19,6 +19,7 @@ #include #include +#include /* * These correspond to the IORESOURCE_IRQ_* defines in @@ -374,6 +375,16 @@ struct softirq_action asmlinkage void do_softirq(void); asmlinkage void __do_softirq(void); + +#ifdef __ARCH_HAS_DO_SOFTIRQ +void do_softirq_own_stack(void); +#else +static inline void do_softirq_own_stack(void) +{ + __do_softirq(); +} +#endif + extern void open_softirq(int nr, void (*action)(struct softirq_action *)); extern void softirq_init(void); extern void __raise_softirq_irqoff(unsigned int nr); diff --git a/kernel/softirq.c b/kernel/softirq.c index 53cc09c..36112cf 100644 --- a/kernel/softirq.c +++ b/kernel/softirq.c @@ -29,7 +29,6 @@ #define CREATE_TRACE_POINTS #include -#include /* - No shared variables, all the data are CPU local. - If a softirq needs serialization, let it serialize itself @@ -283,7 +282,7 @@ restart: tsk_restore_flags(current, old_flags, PF_MEMALLOC); } -#ifndef __ARCH_HAS_DO_SOFTIRQ + asmlinkage void do_softirq(void) { @@ -298,13 +297,11 @@ asmlinkage void do_softirq(void) pending = local_softirq_pending(); if (pending) - __do_softirq(); + do_softirq_own_stack(); local_irq_restore(flags); } -#endif - /* * Enter an interrupt context. */ -- 1.8.3.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/