time: ntp: make 64-bit constants more robust
Impact: cleanup, no functionality changed
- make PPM_SCALE an explicit s64 constant, to
remove (s64) casts from usage sites.
kernel/time/ntp.o:
text data bss dec hex filename
2536 114 136 2786 ae2 ntp.o.before
2536 114 136 2786 ae2 ntp.o.after
md5:
40a7728d1188aa18e83e21a81fa7b150 ntp.o.before.asm
40a7728d1188aa18e83e21a81fa7b150 ntp.o.after.asm
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/include/linux/timex.h b/include/linux/timex.h
index 998a55d..aa3475f 100644
--- a/include/linux/timex.h
+++ b/include/linux/timex.h
@@ -190,7 +190,7 @@
* offset and maximum frequency tolerance.
*/
#define SHIFT_USEC 16 /* frequency offset scale (shift) */
-#define PPM_SCALE (NSEC_PER_USEC << (NTP_SCALE_SHIFT - SHIFT_USEC))
+#define PPM_SCALE ((s64)NSEC_PER_USEC << (NTP_SCALE_SHIFT - SHIFT_USEC))
#define PPM_SCALE_INV_SHIFT 19
#define PPM_SCALE_INV ((1ll << (PPM_SCALE_INV_SHIFT + NTP_SCALE_SHIFT)) / \
PPM_SCALE + 1)
diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c
index 4346ed6..7447d57 100644
--- a/kernel/time/ntp.c
+++ b/kernel/time/ntp.c
@@ -408,7 +408,7 @@
time_status &= ~STA_NANO;
if (txc->modes & ADJ_FREQUENCY) {
- time_freq = (s64)txc->freq * PPM_SCALE;
+ time_freq = txc->freq * PPM_SCALE;
time_freq = min(time_freq, MAXFREQ_SCALED);
time_freq = max(time_freq, -MAXFREQ_SCALED);
}
@@ -505,7 +505,7 @@
result = TIME_ERROR;
txc->freq = shift_right((time_freq >> PPM_SCALE_INV_SHIFT) *
- (s64)PPM_SCALE_INV, NTP_SCALE_SHIFT);
+ PPM_SCALE_INV, NTP_SCALE_SHIFT);
txc->maxerror = time_maxerror;
txc->esterror = time_esterror;
txc->status = time_status;