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| author | Matt Redfearn <matt.redfearn@imgtec.com> | 2016-12-19 14:20:56 +0000 |
|---|---|---|
| committer | Ralf Baechle <ralf@linux-mips.org> | 2017-01-03 16:34:34 +0100 |
| commit | fe8bd18ffea5327344d4ec2bf11f47951212abd0 (patch) | |
| tree | 928a7f758616975d5cc5b66512aa24939c3e9e3f /arch/mips | |
| parent | ae2f5e5ed04a17c1aa1f0a3714c725e12c21d2a9 (diff) | |
| download | lwn-fe8bd18ffea5327344d4ec2bf11f47951212abd0.tar.gz lwn-fe8bd18ffea5327344d4ec2bf11f47951212abd0.zip | |
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>
Acked-by: Jason A. Donenfeld <jason@zx2c4.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Petr Mladek <pmladek@suse.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Aaron Tomlin <atomlin@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14740/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Diffstat (limited to 'arch/mips')
| -rw-r--r-- | arch/mips/include/asm/irq.h | 12 | ||||
| -rw-r--r-- | arch/mips/kernel/asm-offsets.c | 1 | ||||
| -rw-r--r-- | arch/mips/kernel/irq.c | 11 |
3 files changed, 24 insertions, 0 deletions
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 <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) { diff --git a/arch/mips/kernel/asm-offsets.c b/arch/mips/kernel/asm-offsets.c index 6080582a26d1..a7277698d328 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 f8f5836eb3c1..ba150c755fcc 100644 --- a/arch/mips/kernel/irq.c +++ b/arch/mips/kernel/irq.c @@ -25,6 +25,8 @@ #include <linux/atomic.h> #include <linux/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. @@ -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 |