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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>
46 lines
1.1 KiB
C
46 lines
1.1 KiB
C
#include <linux/init.h>
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#include <linux/proc_fs.h>
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#include <linux/sched.h>
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#include <linux/time.h>
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#include <asm/cputime.h>
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static int proc_calc_metrics(char *page, char **start, off_t off,
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int count, int *eof, int len)
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{
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if (len <= off + count)
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*eof = 1;
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*start = page + off;
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len -= off;
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if (len > count)
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len = count;
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if (len < 0)
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len = 0;
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return len;
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}
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static int uptime_read_proc(char *page, char **start, off_t off, int count,
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int *eof, void *data)
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{
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struct timespec uptime;
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struct timespec idle;
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int len;
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cputime_t idletime = cputime_add(init_task.utime, init_task.stime);
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do_posix_clock_monotonic_gettime(&uptime);
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monotonic_to_bootbased(&uptime);
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cputime_to_timespec(idletime, &idle);
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len = sprintf(page, "%lu.%02lu %lu.%02lu\n",
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(unsigned long) uptime.tv_sec,
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(uptime.tv_nsec / (NSEC_PER_SEC / 100)),
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(unsigned long) idle.tv_sec,
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(idle.tv_nsec / (NSEC_PER_SEC / 100)));
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return proc_calc_metrics(page, start, off, count, eof, len);
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}
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static int __init proc_uptime_init(void)
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{
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create_proc_read_entry("uptime", 0, NULL, uptime_read_proc, NULL);
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return 0;
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}
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module_init(proc_uptime_init);
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