6c87df37dc
Turned out some VMware userspace does pread(2) on /proc/uptime, but seqfiles currently don't allow pread() resulting in -ESPIPE. Seqfiles in theory can do pread(), but this can be a long story, so revert to ->read_proc until then. http://bugzilla.kernel.org/show_bug.cgi?id=11856 Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
45 lines
1.1 KiB
C
45 lines
1.1 KiB
C
#include <linux/init.h>
|
|
#include <linux/proc_fs.h>
|
|
#include <linux/sched.h>
|
|
#include <linux/time.h>
|
|
#include <asm/cputime.h>
|
|
|
|
static int proc_calc_metrics(char *page, char **start, off_t off,
|
|
int count, int *eof, int len)
|
|
{
|
|
if (len <= off + count)
|
|
*eof = 1;
|
|
*start = page + off;
|
|
len -= off;
|
|
if (len > count)
|
|
len = count;
|
|
if (len < 0)
|
|
len = 0;
|
|
return len;
|
|
}
|
|
|
|
static int uptime_read_proc(char *page, char **start, off_t off, int count,
|
|
int *eof, void *data)
|
|
{
|
|
struct timespec uptime;
|
|
struct timespec idle;
|
|
int len;
|
|
cputime_t idletime = cputime_add(init_task.utime, init_task.stime);
|
|
|
|
do_posix_clock_monotonic_gettime(&uptime);
|
|
monotonic_to_bootbased(&uptime);
|
|
cputime_to_timespec(idletime, &idle);
|
|
len = sprintf(page, "%lu.%02lu %lu.%02lu\n",
|
|
(unsigned long) uptime.tv_sec,
|
|
(uptime.tv_nsec / (NSEC_PER_SEC / 100)),
|
|
(unsigned long) idle.tv_sec,
|
|
(idle.tv_nsec / (NSEC_PER_SEC / 100)));
|
|
return proc_calc_metrics(page, start, off, count, eof, len);
|
|
}
|
|
|
|
static int __init proc_uptime_init(void)
|
|
{
|
|
create_proc_read_entry("uptime", 0, NULL, uptime_read_proc, NULL);
|
|
return 0;
|
|
}
|
|
module_init(proc_uptime_init);
|