Messages in this thread Patch in this message | | | Date | Mon, 30 Apr 2007 10:44:05 -0700 | From | William Lee Irwin III <> | Subject | [3/6] make IRQ stacks independently configurable (was: Re: [-mm patch] i386: enable 4k stacks by default) |
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On Mon, Apr 30, 2007 at 10:38:19AM -0700, William Lee Irwin III wrote: > Here's what I did for i386 for someone concerned about blowing the stack.
Divorce IRQ stack configuration from CONFIG_4KSTACKS, as it's believed to be an important safety measure regardless of stack size by some users.
Signed-off-by: William Irwin <wli@holomorphy.com>
Index: stack-paranoia/arch/i386/Kconfig.debug =================================================================== --- stack-paranoia.orig/arch/i386/Kconfig.debug 2007-04-30 10:32:56.182682722 -0700 +++ stack-paranoia/arch/i386/Kconfig.debug 2007-04-30 10:34:07.058721717 -0700 @@ -35,6 +35,14 @@ This option will slow down process creation somewhat. +config IRQSTACKS + bool "IRQ stacks" + depends on DEBUG_KERNEL + help + Arranges for per-cpu interrupt stacks so that interrupts + and interrupt-time processing don't consume space on task + stacks. + config VMALLOC_STACK bool "vmalloc() the stack" depends on DEBUG_KERNEL @@ -76,8 +84,7 @@ If you say Y here the kernel will use a 4Kb stacksize for the kernel stack attached to each process/thread. This facilitates running more threads on a system and also reduces the pressure - on the VM subsystem for higher order allocations. This option - will also use IRQ stacks to compensate for the reduced stackspace. + on the VM subsystem for higher order allocations. config 8KSTACKS bool "Use 8KB for kernel stacks" @@ -90,7 +97,6 @@ If you say Y here, the kernel will use a 16KB stacksize. This impedes running more threads on a system and also increases the pressure on the VM subsystem for higher order allocations. - This option will also use IRQ stacks to for additional safety. config 32KSTACKS bool "Use 32KB for kernel stacks" @@ -98,15 +104,14 @@ If you say Y here, the kernel will use a 32KB stacksize. This impedes running more threads on a system and also increases the pressure on the VM subsystem for higher order allocations. - This option will also use IRQ stacks to for additional safety. config 64KSTACKS bool "Use 64KB for kernel stacks" + depends on !IRQSTACKS help If you say Y here, the kernel will use a 64KB stacksize. This impedes running more threads on a system and also increases the pressure on the VM subsystem for higher order allocations. - This option will also use IRQ stacks to for additional safety. endchoice Index: stack-paranoia/arch/i386/kernel/irq.c =================================================================== --- stack-paranoia.orig/arch/i386/kernel/irq.c 2007-04-30 10:26:15.967875780 -0700 +++ stack-paranoia/arch/i386/kernel/irq.c 2007-04-30 10:34:07.058721717 -0700 @@ -47,7 +47,7 @@ #endif } -#ifdef CONFIG_4KSTACKS +#ifdef CONFIG_IRQSTACKS /* * per-CPU IRQ handling contexts (thread information and stack) */ @@ -71,7 +71,7 @@ /* high bit used in ret_from_ code */ int irq = ~regs->orig_eax; struct irq_desc *desc = irq_desc + irq; -#ifdef CONFIG_4KSTACKS +#ifdef CONFIG_IRQSTACKS union irq_ctx *curctx, *irqctx; u32 *isp; #endif @@ -99,7 +99,7 @@ } #endif -#ifdef CONFIG_4KSTACKS +#ifdef CONFIG_IRQSTACKS curctx = (union irq_ctx *) current_thread_info(); irqctx = hardirq_ctx[smp_processor_id()]; @@ -144,7 +144,7 @@ return 1; } -#ifdef CONFIG_4KSTACKS +#ifdef CONFIG_IRQSTACKS /* * These should really be __section__(".bss.page_aligned") as well, but Index: stack-paranoia/include/asm-i386/irq.h =================================================================== --- stack-paranoia.orig/include/asm-i386/irq.h 2007-04-30 10:26:31.904783972 -0700 +++ stack-paranoia/include/asm-i386/irq.h 2007-04-30 10:34:07.058721717 -0700 @@ -24,7 +24,7 @@ # define ARCH_HAS_NMI_WATCHDOG /* See include/linux/nmi.h */ #endif -#ifdef CONFIG_4KSTACKS +#ifdef CONFIG_IRQSTACKS extern void irq_ctx_init(int cpu); extern void irq_ctx_exit(int cpu); # define __ARCH_HAS_DO_SOFTIRQ Index: stack-paranoia/include/asm-i386/module.h =================================================================== --- stack-paranoia.orig/include/asm-i386/module.h 2007-04-30 10:32:56.182682722 -0700 +++ stack-paranoia/include/asm-i386/module.h 2007-04-30 10:34:07.058721717 -0700 @@ -80,7 +80,13 @@ #define MODULE_VMALLOC_STACK "" #endif +#ifdef CONFIG_IRQSTACKS +#define MODULE_IRQSTACKS "IRQSTACKS " +#else +#define MODULE_IRQSTACKS "" +#endif + #define MODULE_ARCH_VERMAGIC MODULE_PROC_FAMILY MODULE_STACKSIZE \ - MODULE_VMALLOC_STACK + MODULE_VMALLOC_STACK MODULE_IRQSTACKS #endif /* _ASM_I386_MODULE_H */ - 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/
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