Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761440AbcLBNkh (ORCPT ); Fri, 2 Dec 2016 08:40:37 -0500 Received: from mailapp01.imgtec.com ([195.59.15.196]:12557 "EHLO mailapp01.imgtec.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1760704AbcLBNjh (ORCPT ); Fri, 2 Dec 2016 08:39:37 -0500 From: Matt Redfearn To: Ralf Baechle CC: , "Jason A . Donenfeld" , Thomas Gleixner , Matt Redfearn , Paolo Bonzini , Chris Metcalf , Petr Mladek , , James Hogan , Paul Burton , Aaron Tomlin , Andrew Morton Subject: [PATCH 1/5] MIPS: Introduce irq_stack Date: Fri, 2 Dec 2016 13:39:13 +0000 Message-ID: <1480685957-18809-2-git-send-email-matt.redfearn@imgtec.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1480685957-18809-1-git-send-email-matt.redfearn@imgtec.com> References: <1480685957-18809-1-git-send-email-matt.redfearn@imgtec.com> MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.150.130.83] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2210 Lines: 80 Allocate a per-cpu irq stack for use within interrupt handlers. Also add a utility function on_irq_stack to determine if a given stack pointer is within the irq stack for that cpu. Signed-off-by: Matt Redfearn --- arch/mips/include/asm/irq.h | 12 ++++++++++++ arch/mips/kernel/asm-offsets.c | 1 + arch/mips/kernel/irq.c | 11 +++++++++++ 3 files changed, 24 insertions(+) diff --git a/arch/mips/include/asm/irq.h b/arch/mips/include/asm/irq.h index 6bf10e796553..956db6e201d1 100644 --- a/arch/mips/include/asm/irq.h +++ b/arch/mips/include/asm/irq.h @@ -17,6 +17,18 @@ #include +#define IRQ_STACK_SIZE THREAD_SIZE + +extern void *irq_stack[NR_CPUS]; + +static inline bool on_irq_stack(int cpu, unsigned long sp) +{ + unsigned long low = (unsigned long)irq_stack[cpu]; + unsigned long high = low + IRQ_STACK_SIZE; + + return (low <= sp && sp <= high); +} + #ifdef CONFIG_I8259 static inline int irq_canonicalize(int irq) { diff --git a/arch/mips/kernel/asm-offsets.c b/arch/mips/kernel/asm-offsets.c index fae2f9447792..4be2763f835d 100644 --- a/arch/mips/kernel/asm-offsets.c +++ b/arch/mips/kernel/asm-offsets.c @@ -102,6 +102,7 @@ void output_thread_info_defines(void) OFFSET(TI_REGS, thread_info, regs); DEFINE(_THREAD_SIZE, THREAD_SIZE); DEFINE(_THREAD_MASK, THREAD_MASK); + DEFINE(_IRQ_STACK_SIZE, IRQ_STACK_SIZE); BLANK(); } diff --git a/arch/mips/kernel/irq.c b/arch/mips/kernel/irq.c index f25f7eab7307..2b0a371b42af 100644 --- a/arch/mips/kernel/irq.c +++ b/arch/mips/kernel/irq.c @@ -25,6 +25,8 @@ #include #include +void *irq_stack[NR_CPUS]; + /* * 'what should we do if we get a hw irq event on an illegal vector'. * each architecture has to answer this themselves. @@ -58,6 +60,15 @@ void __init init_IRQ(void) clear_c0_status(ST0_IM); arch_init_irq(); + + for_each_possible_cpu(i) { + int irq_pages = IRQ_STACK_SIZE / PAGE_SIZE; + void *s = (void *)__get_free_pages(GFP_KERNEL, irq_pages); + + irq_stack[i] = s; + pr_debug("CPU%d IRQ stack at 0x%p - 0x%p\n", i, + irq_stack[i], irq_stack[i] + IRQ_STACK_SIZE); + } } #ifdef CONFIG_DEBUG_STACKOVERFLOW -- 2.7.4