[PATCH 1/8] hardpps: simple fixes replacing clumsy code with abs() macro.

From: Andrey Drobyshev
Date: Wed Feb 15 2017 - 09:33:41 EST


From: Alexander GQ Gerasiov <gq@xxxxxxxxx>

Here are some trivial fixes, including:
* simplify comparisons by using abs() macro
* remove unnecessary variables
* remove duplicate headers
* fix typos

Signed-off-by: Alexander GQ Gerasiov <gq@xxxxxxxxx>
---
kernel/time/ntp.c | 16 +++++-----------
1 file changed, 5 insertions(+), 11 deletions(-)

diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c
index edf19cc..d20891e 100644
--- a/kernel/time/ntp.c
+++ b/kernel/time/ntp.c
@@ -16,7 +16,6 @@
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/rtc.h>
-#include <linux/math64.h>

#include "ntp_internal.h"
#include "timekeeping_internal.h"
@@ -874,7 +873,7 @@ static inline void pps_inc_freq_interval(void)
*/
static long hardpps_update_freq(struct pps_normtime freq_norm)
{
- long delta, delta_mod;
+ long delta;
s64 ftemp;

/* check if the frequency interval was too long */
@@ -896,7 +895,7 @@ static long hardpps_update_freq(struct pps_normtime freq_norm)
freq_norm.sec);
delta = shift_right(ftemp - pps_freq, NTP_SCALE_SHIFT);
pps_freq = ftemp;
- if (delta > PPS_MAXWANDER || delta < -PPS_MAXWANDER) {
+ if (abs(delta) > PPS_MAXWANDER) {
printk_deferred(KERN_WARNING
"hardpps: PPSWANDER: change=%ld\n", delta);
time_status |= STA_PPSWANDER;
@@ -910,10 +909,7 @@ static long hardpps_update_freq(struct pps_normtime freq_norm)
* frequency changes, but is used only for performance
* monitoring
*/
- delta_mod = delta;
- if (delta_mod < 0)
- delta_mod = -delta_mod;
- pps_stabil += (div_s64(((s64)delta_mod) <<
+ pps_stabil += (div_s64(((s64)abs(delta)) <<
(NTP_SCALE_SHIFT - SHIFT_USEC),
NSEC_PER_USEC) - pps_stabil) >> PPS_INTMIN;

@@ -994,10 +990,8 @@ void __hardpps(const struct timespec64 *phase_ts, const struct timespec64 *raw_t
freq_norm = pps_normalize_ts(timespec64_sub(*raw_ts, pps_fbase));

/* check that the signal is in the range
- * [1s - MAXFREQ us, 1s + MAXFREQ us], otherwise reject it */
- if ((freq_norm.sec == 0) ||
- (freq_norm.nsec > MAXFREQ * freq_norm.sec) ||
- (freq_norm.nsec < -MAXFREQ * freq_norm.sec)) {
+ * [1s - MAXFREQ ns, 1s + MAXFREQ ns], otherwise reject it */
+ if (abs(freq_norm.nsec) > MAXFREQ * freq_norm.sec) {
time_status |= STA_PPSJITTER;
/* restart the frequency calibration interval */
pps_fbase = *raw_ts;
--
2.1.4