1// SPDX-License-Identifier: GPL-2.0
2/*
3 * LoongArch specific sysrq operations.
4 *
5 * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
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/tlb.h>
15
16/*
17 * Dump TLB entries on all CPUs.
18 */
19
20static DEFINE_SPINLOCK(show_lock);
21
22static void sysrq_tlbdump_single(void *dummy)
23{
24 unsigned long flags;
25
26 spin_lock_irqsave(&show_lock, flags);
27
28 pr_info("CPU%d:\n", smp_processor_id());
29 dump_tlb_regs();
30 pr_info("\n");
31 dump_tlb_all();
32 pr_info("\n");
33
34 spin_unlock_irqrestore(lock: &show_lock, flags);
35}
36
37#ifdef CONFIG_SMP
38static void sysrq_tlbdump_othercpus(struct work_struct *dummy)
39{
40 smp_call_function(func: sysrq_tlbdump_single, NULL, wait: 0);
41}
42
43static DECLARE_WORK(sysrq_tlbdump, sysrq_tlbdump_othercpus);
44#endif
45
46static void sysrq_handle_tlbdump(u8 key)
47{
48 sysrq_tlbdump_single(NULL);
49#ifdef CONFIG_SMP
50 schedule_work(work: &sysrq_tlbdump);
51#endif
52}
53
54static struct sysrq_key_op sysrq_tlbdump_op = {
55 .handler = sysrq_handle_tlbdump,
56 .help_msg = "show-tlbs(x)",
57 .action_msg = "Show TLB entries",
58 .enable_mask = SYSRQ_ENABLE_DUMP,
59};
60
61static int __init loongarch_sysrq_init(void)
62{
63 return register_sysrq_key(key: 'x', op: &sysrq_tlbdump_op);
64}
65arch_initcall(loongarch_sysrq_init);
66

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