From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753900Ab0JFKoH (ORCPT ); Wed, 6 Oct 2010 06:44:07 -0400 Received: from mail-pw0-f46.google.com ([209.85.160.46]:52817 "EHLO mail-pw0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752295Ab0JFKoE (ORCPT ); Wed, 6 Oct 2010 06:44:04 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=from:to:cc:subject:date:message-id:x-mailer; b=C9P2Q0dKpk9M1kakr/Urve7zYpfYK5wrBTvyrBawXGmGTHq3OP5lymslMA3JF1B15l JkCRrIC3azNqZ2Tt9lhXkmrAq98LJXyfoLmwpaNrChdAZ2ILNpU8ctSXF+HAT7Qgi/nu HjNfytsz+5P6I31+YU8Yhz8ujgEOCKreuDE3E= From: Adam Jiang To: ralf@linux-mips.org Cc: linux-mips@linux-mips.org, linux-kernel@vger.kernel.org, Adam Jiang Subject: [PATCH v3] mips: irq: add stackoverflow detection Date: Wed, 6 Oct 2010 19:41:16 +0900 Message-Id: <1286361676-10743-1-git-send-email-jiang.adam@gmail.com> X-Mailer: git-send-email 1.7.2.2 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Add stackoverflow detection to mips arch This is the 3rd version of the smiple patch. 2K is too big for many system, so I Modified the warning line by following Ralf's suggestion. Signed-off-by: Adam Jiang --- arch/mips/Kconfig.debug | 7 +++++++ arch/mips/include/asm/thread_info.h | 2 ++ arch/mips/kernel/irq.c | 25 +++++++++++++++++++++++++ 3 files changed, 34 insertions(+), 0 deletions(-) diff --git a/arch/mips/Kconfig.debug b/arch/mips/Kconfig.debug index 43dc279..30c58d4 100644 --- a/arch/mips/Kconfig.debug +++ b/arch/mips/Kconfig.debug @@ -67,6 +67,13 @@ config CMDLINE_OVERRIDE Normally, you will choose 'N' here. +config DEBUG_STACKOVERFLOW + bool "Check for stack overflows" + depends on DEBUG_KERNEL + help + This option will cause messages to be printed if free stack + space drops below a certain limit. + config DEBUG_STACK_USAGE bool "Enable stack utilization instrumentation" depends on DEBUG_KERNEL diff --git a/arch/mips/include/asm/thread_info.h b/arch/mips/include/asm/thread_info.h index 70df9c0..b60b28d 100644 --- a/arch/mips/include/asm/thread_info.h +++ b/arch/mips/include/asm/thread_info.h @@ -83,6 +83,8 @@ register struct thread_info *__current_thread_info __asm__("$28"); #define THREAD_SIZE (PAGE_SIZE << THREAD_SIZE_ORDER) #define THREAD_MASK (THREAD_SIZE - 1UL) +#define STACK_WARN (THREAD_SIZE/8) + #define __HAVE_ARCH_THREAD_INFO_ALLOCATOR #ifdef CONFIG_DEBUG_STACK_USAGE diff --git a/arch/mips/kernel/irq.c b/arch/mips/kernel/irq.c index c6345f5..b43edb7 100644 --- a/arch/mips/kernel/irq.c +++ b/arch/mips/kernel/irq.c @@ -151,6 +151,28 @@ void __init init_IRQ(void) #endif } +#ifdef CONFIG_DEBUG_STACKOVERFLOW +static inline void check_stack_overflow(void) +{ + unsigned long sp; + + asm volatile("move %0, $sp" : "=r" (sp)); + sp = sp & THREAD_MASK; + + /* + * check for stack overflow: is there less than STACK_WARN free? + * STACK_WARN is defined as 1/8 of THREAD_SIZE by default. + */ + if (unlikely(sp < (sizeof(struct thread_info) + STACK_WARN))) { + printk("do_IRQ: stack overflow: %ld\n", + sp - sizeof(struct thread_info)); + dump_stack(); + } +} +#else +static inline void check_stack_overflow(void) {} +#endif + /* * do_IRQ handles all normal device IRQ's (the special * SMP cross-CPU interrupts have their own specific @@ -159,6 +181,9 @@ void __init init_IRQ(void) void __irq_entry do_IRQ(unsigned int irq) { irq_enter(); + + check_stack_overflow(); + __DO_IRQ_SMTC_HOOK(irq); generic_handle_irq(irq); irq_exit(); -- 1.7.2.2