1// SPDX-License-Identifier: GPL-2.0
2/*
3 * MIPS specific sysrq operations.
4 *
5 * Copyright (C) 2015 Imagination Technologies Ltd.
6 */
7#include <linux/init.h>
8#include <linux/smp.h>
9#include <linux/spinlock.h>
10#include <linux/sysrq.h>
11#include <linux/workqueue.h>
12
13#include <asm/cpu-features.h>
14#include <asm/mipsregs.h>
15#include <asm/tlbdebug.h>
16
17/*
18 * Dump TLB entries on all CPUs.
19 */
20
21static DEFINE_SPINLOCK(show_lock);
22
23static void sysrq_tlbdump_single(void *dummy)
24{
25 unsigned long flags;
26
27 spin_lock_irqsave(&show_lock, flags);
28
29 pr_info("CPU%d:\n", smp_processor_id());
30 dump_tlb_regs();
31 pr_info("\n");
32 dump_tlb_all();
33 pr_info("\n");
34
35 spin_unlock_irqrestore(lock: &show_lock, flags);
36}
37
38#ifdef CONFIG_SMP
39static void sysrq_tlbdump_othercpus(struct work_struct *dummy)
40{
41 smp_call_function(func: sysrq_tlbdump_single, NULL, wait: 0);
42}
43
44static DECLARE_WORK(sysrq_tlbdump, sysrq_tlbdump_othercpus);
45#endif
46
47static void sysrq_handle_tlbdump(u8 key)
48{
49 sysrq_tlbdump_single(NULL);
50#ifdef CONFIG_SMP
51 schedule_work(work: &sysrq_tlbdump);
52#endif
53}
54
55static const struct sysrq_key_op sysrq_tlbdump_op = {
56 .handler = sysrq_handle_tlbdump,
57 .help_msg = "show-tlbs(x)",
58 .action_msg = "Show TLB entries",
59 .enable_mask = SYSRQ_ENABLE_DUMP,
60};
61
62static int __init mips_sysrq_init(void)
63{
64 return register_sysrq_key(key: 'x', op: &sysrq_tlbdump_op);
65}
66arch_initcall(mips_sysrq_init);
67

source code of linux/arch/mips/kernel/sysrq.c