acrn-kernel/arch/sh/mm/asids-debugfs.c

76 lines
1.8 KiB
C

/*
* debugfs ops for process ASIDs
*
* Copyright (C) 2000, 2001 Paolo Alberelli
* Copyright (C) 2003 - 2008 Paul Mundt
* Copyright (C) 2003, 2004 Richard Curnow
*
* Provides a debugfs file that lists out the ASIDs currently associated
* with the processes.
*
* In the SH-5 case, if the DM.PC register is examined through the debug
* link, this shows ASID + PC. To make use of this, the PID->ASID
* relationship needs to be known. This is primarily for debugging.
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*/
#include <linux/init.h>
#include <linux/module.h>
#include <linux/debugfs.h>
#include <linux/seq_file.h>
#include <linux/spinlock.h>
#include <asm/processor.h>
#include <asm/mmu_context.h>
static int asids_seq_show(struct seq_file *file, void *iter)
{
struct task_struct *p;
read_lock(&tasklist_lock);
for_each_process(p) {
int pid = p->pid;
if (unlikely(!pid))
continue;
if (p->mm)
seq_printf(file, "%5d : %04lx\n", pid,
cpu_asid(smp_processor_id(), p->mm));
}
read_unlock(&tasklist_lock);
return 0;
}
static int asids_debugfs_open(struct inode *inode, struct file *file)
{
return single_open(file, asids_seq_show, inode->i_private);
}
static const struct file_operations asids_debugfs_fops = {
.owner = THIS_MODULE,
.open = asids_debugfs_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
static int __init asids_debugfs_init(void)
{
struct dentry *asids_dentry;
asids_dentry = debugfs_create_file("asids", S_IRUSR, arch_debugfs_dir,
NULL, &asids_debugfs_fops);
if (!asids_dentry)
return -ENOMEM;
return PTR_ERR_OR_ZERO(asids_dentry);
}
module_init(asids_debugfs_init);
MODULE_LICENSE("GPL v2");