ntp: Remove ntp_lock, using the timekeeping locks to protect ntp state
In order to properly handle the NTP state in future changes to the
timekeeping lock management, this patch moves the management of
all of the ntp state under the timekeeping locks.
This allows us to remove the ntp_lock.
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Prarit Bhargava <prarit@redhat.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c
index a331ebc..12ff13a 100644
--- a/kernel/time/ntp.c
+++ b/kernel/time/ntp.c
@@ -22,10 +22,10 @@
/*
* NTP timekeeping variables:
+ *
+ * Note: All of the NTP state is protected by the timekeeping locks.
*/
-DEFINE_RAW_SPINLOCK(ntp_lock);
-
/* USER_HZ period (usecs): */
unsigned long tick_usec = TICK_USEC;
@@ -132,8 +132,6 @@
/**
* pps_clear - Clears the PPS state variables
- *
- * Must be called while holding a write on the ntp_lock
*/
static inline void pps_clear(void)
{
@@ -148,8 +146,6 @@
/* Decrease pps_valid to indicate that another second has passed since
* the last PPS signal. When it reaches 0, indicate that PPS signal is
* missing.
- *
- * Must be called while holding a write on the ntp_lock
*/
static inline void pps_dec_valid(void)
{
@@ -344,10 +340,6 @@
*/
void ntp_clear(void)
{
- unsigned long flags;
-
- raw_spin_lock_irqsave(&ntp_lock, flags);
-
time_adjust = 0; /* stop active adjtime() */
time_status |= STA_UNSYNC;
time_maxerror = NTP_PHASE_LIMIT;
@@ -360,20 +352,12 @@
/* Clear PPS state variables */
pps_clear();
- raw_spin_unlock_irqrestore(&ntp_lock, flags);
-
}
u64 ntp_tick_length(void)
{
- unsigned long flags;
- s64 ret;
-
- raw_spin_lock_irqsave(&ntp_lock, flags);
- ret = tick_length;
- raw_spin_unlock_irqrestore(&ntp_lock, flags);
- return ret;
+ return tick_length;
}
@@ -391,9 +375,6 @@
{
s64 delta;
int leap = 0;
- unsigned long flags;
-
- raw_spin_lock_irqsave(&ntp_lock, flags);
/*
* Leap second processing. If in leap-insert state at the end of the
@@ -475,8 +456,6 @@
time_adjust = 0;
out:
- raw_spin_unlock_irqrestore(&ntp_lock, flags);
-
return leap;
}
@@ -571,10 +550,7 @@
time_status |= txc->status & ~STA_RONLY;
}
-/*
- * Called with ntp_lock held, so we can access and modify
- * all the global NTP state:
- */
+
static inline void process_adjtimex_modes(struct timex *txc,
struct timespec *ts,
s32 *time_tai)
@@ -666,8 +642,6 @@
{
int result;
- raw_spin_lock_irq(&ntp_lock);
-
if (txc->modes & ADJ_ADJTIME) {
long save_adjust = time_adjust;
@@ -708,8 +682,6 @@
/* fill PPS status fields */
pps_fill_timex(txc);
- raw_spin_unlock_irq(&ntp_lock);
-
txc->time.tv_sec = ts->tv_sec;
txc->time.tv_usec = ts->tv_nsec;
if (!(time_status & STA_NANO))
@@ -906,8 +878,6 @@
pts_norm = pps_normalize_ts(*phase_ts);
- raw_spin_lock_irqsave(&ntp_lock, flags);
-
/* clear the error bits, they will be set again if needed */
time_status &= ~(STA_PPSJITTER | STA_PPSWANDER | STA_PPSERROR);
@@ -919,7 +889,6 @@
* just start the frequency interval */
if (unlikely(pps_fbase.tv_sec == 0)) {
pps_fbase = *raw_ts;
- raw_spin_unlock_irqrestore(&ntp_lock, flags);
return;
}
@@ -934,7 +903,6 @@
time_status |= STA_PPSJITTER;
/* restart the frequency calibration interval */
pps_fbase = *raw_ts;
- raw_spin_unlock_irqrestore(&ntp_lock, flags);
pr_err("hardpps: PPSJITTER: bad pulse\n");
return;
}
@@ -951,7 +919,6 @@
hardpps_update_phase(pts_norm.nsec);
- raw_spin_unlock_irqrestore(&ntp_lock, flags);
}
#endif /* CONFIG_NTP_PPS */