| 12345678910111213141516171819202122232425262728293031323334353637383940414243444546474849505152535455565758596061626364656667686970 |
- From: Matt Redfearn <matt.redfearn@imgtec.com>
- Date: Mon, 19 Dec 2016 14:20:56 +0000
- Subject: [PATCH] MIPS: Introduce irq_stack
- 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 <matt.redfearn@imgtec.com>
- ---
- --- a/arch/mips/include/asm/irq.h
- +++ b/arch/mips/include/asm/irq.h
- @@ -17,6 +17,18 @@
-
- #include <irq.h>
-
- +#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)
- {
- --- a/arch/mips/kernel/asm-offsets.c
- +++ b/arch/mips/kernel/asm-offsets.c
- @@ -101,6 +101,7 @@ 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();
- }
-
- --- a/arch/mips/kernel/irq.c
- +++ b/arch/mips/kernel/irq.c
- @@ -25,6 +25,8 @@
- #include <linux/atomic.h>
- #include <asm/uaccess.h>
-
- +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.
- @@ -55,6 +57,15 @@ void __init init_IRQ(void)
- irq_set_noprobe(i);
-
- 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
|
