proc: switch /proc/loadavg to seq_file

and move it to fs/proc/loadavg.c while I'm at it.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>

3 files changed, 52 insertions, 27 deletions

diff --git a/fs/proc/Makefile b/fs/proc/Makefile
index ebaba0213546..bf2ab4df4a8c 100644
--- a/fs/proc/Makefile
+++ b/fs/proc/Makefile
@@ -9,7 +9,7 @@ proc-$(CONFIG_MMU)	:= mmu.o task_mmu.o
 
 proc-y       += inode.o root.o base.o generic.o array.o \
                 proc_tty.o proc_misc.o
-
+proc-y  += loadavg.o
 proc-$(CONFIG_PROC_SYSCTL)      += proc_sysctl.o
 proc-$(CONFIG_NET)              += proc_net.o
 proc-$(CONFIG_PROC_KCORE)       += kcore.o
diff --git a/fs/proc/loadavg.c b/fs/proc/loadavg.c
new file mode 100644
index 000000000000..9bca39cf99ee
--- /dev/null
+++ b/fs/proc/loadavg.c
@@ -0,0 +1,51 @@
+#include <linux/fs.h>
+#include <linux/init.h>
+#include <linux/pid_namespace.h>
+#include <linux/proc_fs.h>
+#include <linux/sched.h>
+#include <linux/seq_file.h>
+#include <linux/seqlock.h>
+#include <linux/time.h>
+
+#define LOAD_INT(x) ((x) >> FSHIFT)
+#define LOAD_FRAC(x) LOAD_INT(((x) & (FIXED_1-1)) * 100)
+
+static int loadavg_proc_show(struct seq_file *m, void *v)
+{
+        int a, b, c;
+        unsigned long seq;
+
+        do {
+                seq = read_seqbegin(&xtime_lock);
+                a = avenrun[0] + (FIXED_1/200);
+                b = avenrun[1] + (FIXED_1/200);
+                c = avenrun[2] + (FIXED_1/200);
+        } while (read_seqretry(&xtime_lock, seq));
+
+        seq_printf(m, "%d.%02d %d.%02d %d.%02d %ld/%d %d\n",
+                LOAD_INT(a), LOAD_FRAC(a),
+                LOAD_INT(b), LOAD_FRAC(b),
+                LOAD_INT(c), LOAD_FRAC(c),
+                nr_running(), nr_threads,
+                task_active_pid_ns(current)->last_pid);
+        return 0;
+}
+
+static int loadavg_proc_open(struct inode *inode, struct file *file)
+{
+        return single_open(file, loadavg_proc_show, NULL);
+}
+
+static const struct file_operations loadavg_proc_fops = {
+        .open           = loadavg_proc_open,
+        .read           = seq_read,
+        .llseek         = seq_lseek,
+        .release        = single_release,
+};
+
+static int __init proc_loadavg_init(void)
+{
+        proc_create("loadavg", 0, NULL, &loadavg_proc_fops);
+        return 0;
+}
+module_init(proc_loadavg_init);
diff --git a/fs/proc/proc_misc.c b/fs/proc/proc_misc.c
index 7ea52c79b2da..ff42206c8aed 100644
--- a/fs/proc/proc_misc.c
+++ b/fs/proc/proc_misc.c
@@ -57,8 +57,6 @@
 #include <asm/div64.h>
 #include "internal.h"
 
-#define LOAD_INT(x) ((x) >> FSHIFT)
-#define LOAD_FRAC(x) LOAD_INT(((x) & (FIXED_1-1)) * 100)
 /*
  * Warning: stuff below (imported functions) assumes that its output will fit
  * into one page. For some of those functions it may be wrong. Moreover, we
@@ -80,29 +78,6 @@ static int proc_calc_metrics(char *page, char **start, off_t off,
         return len;
 }
 
-static int loadavg_read_proc(char *page, char **start, off_t off,
-                                 int count, int *eof, void *data)
-{
-        int a, b, c;
-        int len;
-        unsigned long seq;
-
-        do {
-                seq = read_seqbegin(&xtime_lock);
-                a = avenrun[0] + (FIXED_1/200);
-                b = avenrun[1] + (FIXED_1/200);
-                c = avenrun[2] + (FIXED_1/200);
-        } while (read_seqretry(&xtime_lock, seq));
-
-        len = sprintf(page,"%d.%02d %d.%02d %d.%02d %ld/%d %d\n",
-                LOAD_INT(a), LOAD_FRAC(a),
-                LOAD_INT(b), LOAD_FRAC(b),
-                LOAD_INT(c), LOAD_FRAC(c),
-                nr_running(), nr_threads,
-                task_active_pid_ns(current)->last_pid);
-        return proc_calc_metrics(page, start, off, count, eof, len);
-}
-
 static int uptime_read_proc(char *page, char **start, off_t off,
                                  int count, int *eof, void *data)
 {
@@ -861,7 +836,6 @@ void __init proc_misc_init(void)
                 char *name;
                 int (*read_proc)(char*,char**,off_t,int,int*,void*);
         } *p, simple_ones[] = {
-                {"loadavg",     loadavg_read_proc},
                 {"uptime",      uptime_read_proc},
                 {"meminfo",     meminfo_read_proc},
                 {"version",     version_read_proc},