linux-stable/arch/sh/mm/asids-debugfs.c
Greg Kroah-Hartman 03eb2a08fc sh: no need to check return value of debugfs_create functions
When calling debugfs functions, there is no need to ever check the
return value.  The function can work or not, but the code logic should
never do something different based on this.

Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Cc: <linux-sh@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-03 15:39:40 +02:00

70 lines
1.7 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/debugfs.h>
#include <linux/seq_file.h>
#include <linux/spinlock.h>
#include <linux/sched/signal.h>
#include <linux/sched/task.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)
{
debugfs_create_file("asids", S_IRUSR, arch_debugfs_dir, NULL,
&asids_debugfs_fops);
return 0;
}
device_initcall(asids_debugfs_init);