Commit 110ed28246a0063a5984d7f72ba5c97f154a51cf
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0e670685e4
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sh: Decouple 4k and soft/hardirq stacks.
While using separate IRQ stacks can cut down on stack consumption, many users can also use 4k stacks directly without the additional need of separate stacks for soft and hardirqs. With this split, we support the same rationale for 4KSTACKS as m68knommu, with the IRQSTACKS abstraction as per ppc64. Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Showing 3 changed files with 13 additions and 5 deletions Side-by-side Diff
arch/sh/Kconfig.debug
| ... | ... | @@ -86,6 +86,14 @@ |
| 86 | 86 | on the VM subsystem for higher order allocations. This option |
| 87 | 87 | will also use IRQ stacks to compensate for the reduced stackspace. |
| 88 | 88 | |
| 89 | +config IRQSTACKS | |
| 90 | + bool "Use separate kernel stacks when processing interrupts" | |
| 91 | + depends on DEBUG_KERNEL | |
| 92 | + help | |
| 93 | + If you say Y here the kernel will use separate kernel stacks | |
| 94 | + for handling hard and soft interrupts. This can help avoid | |
| 95 | + overflowing the process kernel stacks. | |
| 96 | + | |
| 89 | 97 | config SH_KGDB |
| 90 | 98 | bool "Include KGDB kernel debugger" |
| 91 | 99 | select FRAME_POINTER |
arch/sh/kernel/irq.c
| ... | ... | @@ -69,7 +69,7 @@ |
| 69 | 69 | } |
| 70 | 70 | #endif |
| 71 | 71 | |
| 72 | -#ifdef CONFIG_4KSTACKS | |
| 72 | +#ifdef CONFIG_IRQSTACKS | |
| 73 | 73 | /* |
| 74 | 74 | * per-CPU IRQ handling contexts (thread information and stack) |
| 75 | 75 | */ |
| ... | ... | @@ -85,7 +85,7 @@ |
| 85 | 85 | asmlinkage int do_IRQ(unsigned int irq, struct pt_regs *regs) |
| 86 | 86 | { |
| 87 | 87 | struct pt_regs *old_regs = set_irq_regs(regs); |
| 88 | -#ifdef CONFIG_4KSTACKS | |
| 88 | +#ifdef CONFIG_IRQSTACKS | |
| 89 | 89 | union irq_ctx *curctx, *irqctx; |
| 90 | 90 | #endif |
| 91 | 91 | |
| ... | ... | @@ -109,7 +109,7 @@ |
| 109 | 109 | |
| 110 | 110 | irq = irq_demux(evt2irq(irq)); |
| 111 | 111 | |
| 112 | -#ifdef CONFIG_4KSTACKS | |
| 112 | +#ifdef CONFIG_IRQSTACKS | |
| 113 | 113 | curctx = (union irq_ctx *)current_thread_info(); |
| 114 | 114 | irqctx = hardirq_ctx[smp_processor_id()]; |
| 115 | 115 | |
| ... | ... | @@ -157,7 +157,7 @@ |
| 157 | 157 | return 1; |
| 158 | 158 | } |
| 159 | 159 | |
| 160 | -#ifdef CONFIG_4KSTACKS | |
| 160 | +#ifdef CONFIG_IRQSTACKS | |
| 161 | 161 | static char softirq_stack[NR_CPUS * THREAD_SIZE] |
| 162 | 162 | __attribute__((__section__(".bss.page_aligned"))); |
| 163 | 163 |
include/asm-sh/irq.h
| ... | ... | @@ -41,7 +41,7 @@ |
| 41 | 41 | #define irq_canonicalize(irq) (irq) |
| 42 | 42 | #define irq_demux(irq) sh_mv.mv_irq_demux(irq) |
| 43 | 43 | |
| 44 | -#ifdef CONFIG_4KSTACKS | |
| 44 | +#ifdef CONFIG_IRQSTACKS | |
| 45 | 45 | extern void irq_ctx_init(int cpu); |
| 46 | 46 | extern void irq_ctx_exit(int cpu); |
| 47 | 47 | # define __ARCH_HAS_DO_SOFTIRQ |