Commit f3f99d37 authored Jun 17, 2016 by Arnd Bergmann Committed by Tejun Heo Jun 17, 2016

ata: fix "ering" sysfs time printing



The sysfs file for the libata error handling has multiple issues
in the way it prints time stamps:

 * it prints a 9-digit nanosecond value using a %06lu format string,
   which drops some leading zeroes
 * it converts a 64-bit jiffes value to a timespec using
   jiffies_to_timespec(), which takes a 'long' argument, so the
   result is wrong after a jiffies overflow (49 days).
 * we try to avoid using timespec because that generally overflows
   in 2038, although this particular usage is ok.

This replaces the jiffies_to_timespec call with an open-coded
implementation that gets it right.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Tejun Heo <tj@kernel.org>

parent 8dbcad02

drivers/ata/libata-transport.c

+5 −4

Original line number	Diff line number	Diff line
		@@ -495,12 +495,13 @@ struct ata_show_ering_arg {
		static int ata_show_ering(struct ata_ering_entry ent, void void_arg)
		{
		struct ata_show_ering_arg* arg = void_arg;
		struct timespec time;
		u64 seconds;
		u32 rem;

		jiffies_to_timespec(ent->timestamp,&time);
		seconds = div_u64_rem(ent->timestamp, HZ, &rem);
		arg->written += sprintf(arg->buf + arg->written,
		"[%5lu.%06lu]",
		time.tv_sec, time.tv_nsec);
		"[%5llu.%09lu]", seconds,
		rem * NSEC_PER_SEC / HZ);
		arg->written += get_ata_err_names(ent->err_mask,
		arg->buf + arg->written);
		return 0;