diff options
| author | James Hogan <james.hogan@imgtec.com> | 2015-05-19 09:50:29 +0100 |
|---|---|---|
| committer | Ralf Baechle <ralf@linux-mips.org> | 2015-06-21 21:52:27 +0200 |
| commit | d1e9a4f547354ca258b6200ab6b1f0e4909b92e8 (patch) | |
| tree | 83296bd594cda572fb2159960c9b29d739b1145d | |
| parent | 37dd3818d1f3d875125cffb6d84392df1a38f2f9 (diff) | |
| download | lwn-d1e9a4f547354ca258b6200ab6b1f0e4909b92e8.tar.gz lwn-d1e9a4f547354ca258b6200ab6b1f0e4909b92e8.zip | |
MIPS: Add SysRq operation to dump TLBs on all CPUs
Add a MIPS specific SysRq operation to dump the TLB entries on all CPUs,
using the 'x' trigger key.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/10072/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
| -rw-r--r-- | arch/mips/kernel/Makefile | 1 | ||||
| -rw-r--r-- | arch/mips/kernel/sysrq.c | 77 | ||||
| -rw-r--r-- | drivers/tty/sysrq.c | 1 |
3 files changed, 79 insertions, 0 deletions
diff --git a/arch/mips/kernel/Makefile b/arch/mips/kernel/Makefile index d3d2ff2d76dc..a2debcbedb6d 100644 --- a/arch/mips/kernel/Makefile +++ b/arch/mips/kernel/Makefile @@ -77,6 +77,7 @@ obj-$(CONFIG_MIPS32_O32) += binfmt_elfo32.o scall64-o32.o obj-$(CONFIG_KGDB) += kgdb.o obj-$(CONFIG_PROC_FS) += proc.o +obj-$(CONFIG_MAGIC_SYSRQ) += sysrq.o obj-$(CONFIG_64BIT) += cpu-bugs64.o diff --git a/arch/mips/kernel/sysrq.c b/arch/mips/kernel/sysrq.c new file mode 100644 index 000000000000..5b539f5fc9d9 --- /dev/null +++ b/arch/mips/kernel/sysrq.c @@ -0,0 +1,77 @@ +/* + * MIPS specific sysrq operations. + * + * Copyright (C) 2015 Imagination Technologies Ltd. + */ +#include <linux/init.h> +#include <linux/smp.h> +#include <linux/spinlock.h> +#include <linux/sysrq.h> +#include <linux/workqueue.h> + +#include <asm/cpu-features.h> +#include <asm/mipsregs.h> +#include <asm/tlbdebug.h> + +/* + * Dump TLB entries on all CPUs. + */ + +static DEFINE_SPINLOCK(show_lock); + +static void sysrq_tlbdump_single(void *dummy) +{ + const int field = 2 * sizeof(unsigned long); + unsigned long flags; + + spin_lock_irqsave(&show_lock, flags); + + pr_info("CPU%d:\n", smp_processor_id()); + pr_info("Index : %0x\n", read_c0_index()); + pr_info("Pagemask: %0x\n", read_c0_pagemask()); + pr_info("EntryHi : %0*lx\n", field, read_c0_entryhi()); + pr_info("EntryLo0: %0*lx\n", field, read_c0_entrylo0()); + pr_info("EntryLo1: %0*lx\n", field, read_c0_entrylo1()); + pr_info("Wired : %0x\n", read_c0_wired()); + pr_info("Pagegrain: %0x\n", read_c0_pagegrain()); + if (cpu_has_htw) { + pr_info("PWField : %0*lx\n", field, read_c0_pwfield()); + pr_info("PWSize : %0*lx\n", field, read_c0_pwsize()); + pr_info("PWCtl : %0x\n", read_c0_pwctl()); + } + pr_info("\n"); + dump_tlb_all(); + pr_info("\n"); + + spin_unlock_irqrestore(&show_lock, flags); +} + +#ifdef CONFIG_SMP +static void sysrq_tlbdump_othercpus(struct work_struct *dummy) +{ + smp_call_function(sysrq_tlbdump_single, NULL, 0); +} + +static DECLARE_WORK(sysrq_tlbdump, sysrq_tlbdump_othercpus); +#endif + +static void sysrq_handle_tlbdump(int key) +{ + sysrq_tlbdump_single(NULL); +#ifdef CONFIG_SMP + schedule_work(&sysrq_tlbdump); +#endif +} + +static struct sysrq_key_op sysrq_tlbdump_op = { + .handler = sysrq_handle_tlbdump, + .help_msg = "show-tlbs(x)", + .action_msg = "Show TLB entries", + .enable_mask = SYSRQ_ENABLE_DUMP, +}; + +static int __init mips_sysrq_init(void) +{ + return register_sysrq_key('x', &sysrq_tlbdump_op); +} +arch_initcall(mips_sysrq_init); diff --git a/drivers/tty/sysrq.c b/drivers/tty/sysrq.c index 843f2cdc280b..8ba52e56bb8b 100644 --- a/drivers/tty/sysrq.c +++ b/drivers/tty/sysrq.c @@ -463,6 +463,7 @@ static struct sysrq_key_op *sysrq_key_table[36] = { /* v: May be registered for frame buffer console restore */ NULL, /* v */ &sysrq_showstate_blocked_op, /* w */ + /* x: May be registered on mips for TLB dump */ /* x: May be registered on ppc/powerpc for xmon */ /* x: May be registered on sparc64 for global PMU dump */ NULL, /* x */ |