[PATCH] proc: mark more files as permanent

From: Alexey Dobriyan
Date: Tue Sep 20 2022 - 13:35:39 EST


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.

Signed-off-by: Alexey Dobriyan <adobriyan@xxxxxxxxx>
---

fs/proc/devices.c | 6 +++++-
fs/proc/internal.h | 5 +++++
fs/proc/loadavg.c | 6 +++++-
fs/proc/meminfo.c | 5 ++++-
fs/proc/page.c | 3 +++
fs/proc/softirqs.c | 6 +++++-
fs/proc/uptime.c | 6 +++++-
fs/proc/version.c | 6 +++++-
8 files changed, 37 insertions(+), 6 deletions(-)

--- a/fs/proc/devices.c
+++ b/fs/proc/devices.c
@@ -4,6 +4,7 @@
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/blkdev.h>
+#include "internal.h"

static int devinfo_show(struct seq_file *f, void *v)
{
@@ -54,7 +55,10 @@ static const struct seq_operations devinfo_ops = {

static int __init proc_devices_init(void)
{
- proc_create_seq("devices", 0, NULL, &devinfo_ops);
+ struct proc_dir_entry *pde;
+
+ pde = proc_create_seq("devices", 0, NULL, &devinfo_ops);
+ pde_make_permanent(pde);
return 0;
}
fs_initcall(proc_devices_init);
--- a/fs/proc/internal.h
+++ b/fs/proc/internal.h
@@ -79,6 +79,11 @@ static inline bool pde_is_permanent(const struct proc_dir_entry *pde)
return pde->flags & PROC_ENTRY_PERMANENT;
}

+static inline void pde_make_permanent(struct proc_dir_entry *pde)
+{
+ pde->flags |= PROC_ENTRY_PERMANENT;
+}
+
extern struct kmem_cache *proc_dir_entry_cache;
void pde_free(struct proc_dir_entry *pde);

--- a/fs/proc/loadavg.c
+++ b/fs/proc/loadavg.c
@@ -9,6 +9,7 @@
#include <linux/seq_file.h>
#include <linux/seqlock.h>
#include <linux/time.h>
+#include "internal.h"

static int loadavg_proc_show(struct seq_file *m, void *v)
{
@@ -27,7 +28,10 @@ static int loadavg_proc_show(struct seq_file *m, void *v)

static int __init proc_loadavg_init(void)
{
- proc_create_single("loadavg", 0, NULL, loadavg_proc_show);
+ struct proc_dir_entry *pde;
+
+ pde = proc_create_single("loadavg", 0, NULL, loadavg_proc_show);
+ pde_make_permanent(pde);
return 0;
}
fs_initcall(proc_loadavg_init);
--- a/fs/proc/meminfo.c
+++ b/fs/proc/meminfo.c
@@ -162,7 +162,10 @@ static int meminfo_proc_show(struct seq_file *m, void *v)

static int __init proc_meminfo_init(void)
{
- proc_create_single("meminfo", 0, NULL, meminfo_proc_show);
+ struct proc_dir_entry *pde;
+
+ pde = proc_create_single("meminfo", 0, NULL, meminfo_proc_show);
+ pde_make_permanent(pde);
return 0;
}
fs_initcall(proc_meminfo_init);
--- a/fs/proc/page.c
+++ b/fs/proc/page.c
@@ -91,6 +91,7 @@ static ssize_t kpagecount_read(struct file *file, char __user *buf,
}

static const struct proc_ops kpagecount_proc_ops = {
+ .proc_flags = PROC_ENTRY_PERMANENT,
.proc_lseek = mem_lseek,
.proc_read = kpagecount_read,
};
@@ -268,6 +269,7 @@ static ssize_t kpageflags_read(struct file *file, char __user *buf,
}

static const struct proc_ops kpageflags_proc_ops = {
+ .proc_flags = PROC_ENTRY_PERMANENT,
.proc_lseek = mem_lseek,
.proc_read = kpageflags_read,
};
@@ -322,6 +324,7 @@ static ssize_t kpagecgroup_read(struct file *file, char __user *buf,
}

static const struct proc_ops kpagecgroup_proc_ops = {
+ .proc_flags = PROC_ENTRY_PERMANENT,
.proc_lseek = mem_lseek,
.proc_read = kpagecgroup_read,
};
--- a/fs/proc/softirqs.c
+++ b/fs/proc/softirqs.c
@@ -3,6 +3,7 @@
#include <linux/kernel_stat.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
+#include "internal.h"

/*
* /proc/softirqs ... display the number of softirqs
@@ -27,7 +28,10 @@ static int show_softirqs(struct seq_file *p, void *v)

static int __init proc_softirqs_init(void)
{
- proc_create_single("softirqs", 0, NULL, show_softirqs);
+ struct proc_dir_entry *pde;
+
+ pde = proc_create_single("softirqs", 0, NULL, show_softirqs);
+ pde_make_permanent(pde);
return 0;
}
fs_initcall(proc_softirqs_init);
--- a/fs/proc/uptime.c
+++ b/fs/proc/uptime.c
@@ -7,6 +7,7 @@
#include <linux/time.h>
#include <linux/time_namespace.h>
#include <linux/kernel_stat.h>
+#include "internal.h"

static int uptime_proc_show(struct seq_file *m, void *v)
{
@@ -39,7 +40,10 @@ static int uptime_proc_show(struct seq_file *m, void *v)

static int __init proc_uptime_init(void)
{
- proc_create_single("uptime", 0, NULL, uptime_proc_show);
+ struct proc_dir_entry *pde;
+
+ pde = proc_create_single("uptime", 0, NULL, uptime_proc_show);
+ pde_make_permanent(pde);
return 0;
}
fs_initcall(proc_uptime_init);
--- a/fs/proc/version.c
+++ b/fs/proc/version.c
@@ -5,6 +5,7 @@
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/utsname.h>
+#include "internal.h"

static int version_proc_show(struct seq_file *m, void *v)
{
@@ -17,7 +18,10 @@ static int version_proc_show(struct seq_file *m, void *v)

static int __init proc_version_init(void)
{
- proc_create_single("version", 0, NULL, version_proc_show);
+ struct proc_dir_entry *pde;
+
+ pde = proc_create_single("version", 0, NULL, version_proc_show);
+ pde_make_permanent(pde);
return 0;
}
fs_initcall(proc_version_init);