| Message ID | 20160617153739.429055-1-arnd@arndb.de |
|---|---|
| State | Not Applicable |
| Delegated to: | David Miller |
| Headers | show |
On Fri, Jun 17, 2016 at 05:37:12PM +0200, Arnd Bergmann wrote: > 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> Heh, I'm not even sure why we're exposing this but it's already there. Applied to libata/for-4.8. Thanks!
diff --git a/drivers/ata/libata-transport.c b/drivers/ata/libata-transport.c index e2d94972962d..7ef16c085058 100644 --- a/drivers/ata/libata-transport.c +++ b/drivers/ata/libata-transport.c @@ -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;
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> --- drivers/ata/libata-transport.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-)