forked from Minki/linux
ef1d61781b
Mark /proc/devices /proc/kpagecount /proc/kpageflags /proc/kpagecgroup /proc/loadavg /proc/meminfo /proc/softirqs /proc/uptime /proc/version as permanent /proc entries, saving alloc/free and some list/spinlock ops per use. These files are never removed by the kernel so it is OK to mark them. Link: https://lkml.kernel.org/r/Yyn527DzDMa+r0Yj@localhost.localdomain Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
65 lines
1.2 KiB
C
65 lines
1.2 KiB
C
// SPDX-License-Identifier: GPL-2.0
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#include <linux/fs.h>
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#include <linux/init.h>
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#include <linux/proc_fs.h>
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#include <linux/seq_file.h>
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#include <linux/blkdev.h>
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#include "internal.h"
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static int devinfo_show(struct seq_file *f, void *v)
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{
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int i = *(loff_t *) v;
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if (i < CHRDEV_MAJOR_MAX) {
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if (i == 0)
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seq_puts(f, "Character devices:\n");
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chrdev_show(f, i);
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}
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#ifdef CONFIG_BLOCK
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else {
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i -= CHRDEV_MAJOR_MAX;
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if (i == 0)
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seq_puts(f, "\nBlock devices:\n");
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blkdev_show(f, i);
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}
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#endif
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return 0;
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}
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static void *devinfo_start(struct seq_file *f, loff_t *pos)
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{
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if (*pos < (BLKDEV_MAJOR_MAX + CHRDEV_MAJOR_MAX))
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return pos;
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return NULL;
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}
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static void *devinfo_next(struct seq_file *f, void *v, loff_t *pos)
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{
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(*pos)++;
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if (*pos >= (BLKDEV_MAJOR_MAX + CHRDEV_MAJOR_MAX))
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return NULL;
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return pos;
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}
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static void devinfo_stop(struct seq_file *f, void *v)
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{
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/* Nothing to do */
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}
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static const struct seq_operations devinfo_ops = {
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.start = devinfo_start,
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.next = devinfo_next,
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.stop = devinfo_stop,
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.show = devinfo_show
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};
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static int __init proc_devices_init(void)
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{
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struct proc_dir_entry *pde;
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pde = proc_create_seq("devices", 0, NULL, &devinfo_ops);
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pde_make_permanent(pde);
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return 0;
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}
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fs_initcall(proc_devices_init);
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