[PATCH 4/5] ntp.c code flow clenaups (from Ingo)
From: john stultz
Date: Sat Mar 15 2008 - 00:13:04 EST
From: Ingo Molnar <mingo@xxxxxxx>
Subject: [patch] ntp: clean up code flow
clean up the flow of code by splitting the way too large and way too
nested do_adjtimex() function.
no change in the logic.
Signed-off-by: Ingo Molnar <mingo@xxxxxxx>
Merged on top of Roman's very similar cleanups.
(In other words: Blame John for the merge screwups).
Signed-off-by: John Stultz <johnstul@xxxxxxxxxx>
Index: linux-2.6/kernel/time/ntp.c
===================================================================
--- linux-2.6.orig/kernel/time/ntp.c 2008-03-14 20:10:41.000000000 -0700
+++ linux-2.6/kernel/time/ntp.c 2008-03-14 20:43:48.000000000 -0700
@@ -275,6 +275,87 @@ static void notify_cmos_timer(void)
static inline void notify_cmos_timer(void) { }
#endif
+static inline void process_adjtimex_adj_offset(struct timex *txc, long sec)
+{
+ if (txc->modes & ADJ_STATUS) {
+ if ((time_status & STA_PLL) && !(txc->status & STA_PLL)) {
+ time_state = TIME_OK;
+ time_status = STA_UNSYNC;
+ }
+ /* only set allowed bits */
+ time_status &= STA_RONLY;
+ time_status |= txc->status & ~STA_RONLY;
+
+ switch (time_state) {
+ case TIME_OK:
+ start_timer:
+ if (time_status & STA_INS) {
+ time_state = TIME_INS;
+ sec += 86400 - sec % 86400;
+ hrtimer_start(&leap_timer, ktime_set(sec, 0), HRTIMER_MODE_ABS);
+ } else if (time_status & STA_DEL) {
+ time_state = TIME_DEL;
+ sec += 86400 - (sec + 1) % 86400;
+ hrtimer_start(&leap_timer, ktime_set(sec, 0), HRTIMER_MODE_ABS);
+ }
+ break;
+ case TIME_INS:
+ case TIME_DEL:
+ time_state = TIME_OK;
+ goto start_timer;
+ break;
+ case TIME_WAIT:
+ if (!(time_status & (STA_INS | STA_DEL)))
+ time_state = TIME_OK;
+ break;
+ case TIME_OOP:
+ hrtimer_restart(&leap_timer);
+ break;
+ }
+ }
+
+ if (txc->modes & ADJ_NANO)
+ time_status |= STA_NANO;
+ if (txc->modes & ADJ_MICRO)
+ time_status &= ~STA_NANO;
+
+ if (txc->modes & ADJ_FREQUENCY) {
+ time_freq = (s64)txc->freq * PPM_SCALE;
+ time_freq = min(time_freq, MAXFREQ_SCALED);
+ time_freq = max(time_freq, -MAXFREQ_SCALED);
+ }
+
+ if (txc->modes & ADJ_MAXERROR)
+ time_maxerror = txc->maxerror;
+ if (txc->modes & ADJ_ESTERROR)
+ time_esterror = txc->esterror;
+
+ if (txc->modes & ADJ_TIMECONST) {
+ time_constant = txc->constant;
+ if (!(time_status & STA_NANO))
+ time_constant += 4;
+ time_constant = min(time_constant, (long)MAXTC);
+ time_constant = max(time_constant, 0l);
+ }
+
+ if (txc->modes & ADJ_TAI && txc->constant > 0)
+ time_tai = txc->constant;
+
+ if (txc->modes & ADJ_OFFSET) {
+ if (txc->modes == ADJ_OFFSET_SINGLESHOT)
+ /* adjtime() is independent from ntp_adjtime() */
+ time_adjust = txc->offset;
+ else
+ ntp_update_offset(txc->offset);
+ }
+
+ if (txc->modes & ADJ_TICK)
+ tick_usec = txc->tick;
+
+ if (txc->modes & (ADJ_TICK|ADJ_FREQUENCY|ADJ_OFFSET))
+ ntp_update_frequency();
+}
+
/*
* adjtimex mainly allows reading (and writing, if superuser) of
* kernel time-keeping variables. used by xntpd.
@@ -282,7 +363,7 @@ static inline void notify_cmos_timer(voi
int do_adjtimex(struct timex *txc)
{
struct timespec ts;
- long save_adjust, sec;
+ long save_adjust;
int result;
/* In order to modify anything, you gotta be super-user! */
@@ -306,6 +387,7 @@ int do_adjtimex(struct timex *txc)
if (time_state != TIME_OK && txc->modes & ADJ_STATUS)
hrtimer_cancel(&leap_timer);
+
getnstimeofday(&ts);
write_seqlock_irq(&xtime_lock);
@@ -314,121 +396,42 @@ int do_adjtimex(struct timex *txc)
save_adjust = time_adjust;
/* If there are input parameters, then process them */
- if (txc->modes) {
- if (txc->modes & ADJ_STATUS) {
- if ((time_status & STA_PLL) &&
- !(txc->status & STA_PLL)) {
- time_state = TIME_OK;
- time_status = STA_UNSYNC;
- }
- /* only set allowed bits */
- time_status &= STA_RONLY;
- time_status |= txc->status & ~STA_RONLY;
-
- switch (time_state) {
- case TIME_OK:
- start_timer:
- sec = ts.tv_sec;
- if (time_status & STA_INS) {
- time_state = TIME_INS;
- sec += 86400 - sec % 86400;
- hrtimer_start(&leap_timer, ktime_set(sec, 0), HRTIMER_MODE_ABS);
- } else if (time_status & STA_DEL) {
- time_state = TIME_DEL;
- sec += 86400 - (sec + 1) % 86400;
- hrtimer_start(&leap_timer, ktime_set(sec, 0), HRTIMER_MODE_ABS);
- }
- break;
- case TIME_INS:
- case TIME_DEL:
- time_state = TIME_OK;
- goto start_timer;
- break;
- case TIME_WAIT:
- if (!(time_status & (STA_INS | STA_DEL)))
- time_state = TIME_OK;
- break;
- case TIME_OOP:
- hrtimer_restart(&leap_timer);
- break;
- }
- }
-
- if (txc->modes & ADJ_NANO)
- time_status |= STA_NANO;
- if (txc->modes & ADJ_MICRO)
- time_status &= ~STA_NANO;
-
- if (txc->modes & ADJ_FREQUENCY) {
- time_freq = (s64)txc->freq * PPM_SCALE;
- time_freq = min(time_freq, MAXFREQ_SCALED);
- time_freq = max(time_freq, -MAXFREQ_SCALED);
- }
-
- if (txc->modes & ADJ_MAXERROR)
- time_maxerror = txc->maxerror;
- if (txc->modes & ADJ_ESTERROR)
- time_esterror = txc->esterror;
-
- if (txc->modes & ADJ_TIMECONST) {
- time_constant = txc->constant;
- if (!(time_status & STA_NANO))
- time_constant += 4;
- time_constant = min(time_constant, (long)MAXTC);
- time_constant = max(time_constant, 0l);
- }
-
- if (txc->modes & ADJ_TAI && txc->constant > 0)
- time_tai = txc->constant;
-
- if (txc->modes & ADJ_OFFSET) {
- if (txc->modes == ADJ_OFFSET_SINGLESHOT)
- /* adjtime() is independent from ntp_adjtime() */
- time_adjust = txc->offset;
- else
- ntp_update_offset(txc->offset);
- }
- if (txc->modes & ADJ_TICK)
- tick_usec = txc->tick;
-
- if (txc->modes & (ADJ_TICK|ADJ_FREQUENCY|ADJ_OFFSET))
- ntp_update_frequency();
- }
+ if (txc->modes)
+ process_adjtimex_adj_offset(txc, ts.tv_sec);
result = time_state; /* mostly `TIME_OK' */
if (time_status & (STA_UNSYNC|STA_CLOCKERR))
result = TIME_ERROR;
if ((txc->modes == ADJ_OFFSET_SINGLESHOT) ||
- (txc->modes == ADJ_OFFSET_SS_READ))
+ (txc->modes == ADJ_OFFSET_SS_READ)) {
txc->offset = save_adjust;
- else {
+ } else {
txc->offset = shift_right(time_offset * NTP_INTERVAL_FREQ,
NTP_SCALE_SHIFT);
if (!(time_status & STA_NANO))
txc->offset /= NSEC_PER_USEC;
}
- txc->freq = shift_right((s32)(time_freq >> PPM_SCALE_INV_SHIFT) *
- (s64)PPM_SCALE_INV,
- NTP_SCALE_SHIFT);
- txc->maxerror = time_maxerror;
- txc->esterror = time_esterror;
- txc->status = time_status;
- txc->constant = time_constant;
- txc->precision = 1;
- txc->tolerance = MAXFREQ_SCALED / PPM_SCALE;
- txc->tick = tick_usec;
- txc->tai = time_tai;
+ txc->freq = shift_right((s32)(time_freq >> PPM_SCALE_INV_SHIFT) *
+ (s64)PPM_SCALE_INV, NTP_SCALE_SHIFT);
+ txc->maxerror = time_maxerror;
+ txc->esterror = time_esterror;
+ txc->status = time_status;
+ txc->constant = time_constant;
+ txc->precision = 1;
+ txc->tolerance = MAXFREQ_SCALED / PPM_SCALE;
+ txc->tick = tick_usec;
+ txc->tai = time_tai;
/* PPS is not implemented, so these are zero */
- txc->ppsfreq = 0;
- txc->jitter = 0;
- txc->shift = 0;
- txc->stabil = 0;
- txc->jitcnt = 0;
- txc->calcnt = 0;
- txc->errcnt = 0;
- txc->stbcnt = 0;
+ txc->ppsfreq = 0;
+ txc->jitter = 0;
+ txc->shift = 0;
+ txc->stabil = 0;
+ txc->jitcnt = 0;
+ txc->calcnt = 0;
+ txc->errcnt = 0;
+ txc->stbcnt = 0;
write_sequnlock_irq(&xtime_lock);
txc->time.tv_sec = ts.tv_sec;
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/