From 423eb5453044296a91913ff7ed0a19151ee6d342 Mon Sep 17 00:00:00 2001 From: Jiri Benc Date: Wed, 11 Jun 2014 21:35:12 +0200 Subject: [PATCH] phc2sys: split update_sync_offset Split the generic (global) part of update_sync_offset and the part that affects individual clocks. This is in preparation for phc2sys handling synchronization of more clocks. Signed-off-by: Jiri Benc --- phc2sys.c | 71 ++++++++++++++++++++++++++++++++++++++++++------------- 1 file changed, 55 insertions(+), 16 deletions(-) diff --git a/phc2sys.c b/phc2sys.c index 0581eb5..19dce45 100644 --- a/phc2sys.c +++ b/phc2sys.c @@ -60,7 +60,9 @@ #define PMC_UPDATE_INTERVAL (60 * NS_PER_SEC) struct clock; -static int update_sync_offset(struct clock *clock, int64_t offset, uint64_t ts); +static int update_sync_offset(struct clock *clock); +static int clock_handle_leap(struct clock *clock, clockid_t src, + int64_t offset, uint64_t ts, int do_leap); static clockid_t clock_open(char *device) { @@ -181,13 +183,14 @@ static void update_clock_stats(struct clock *clock, stats_reset(clock->delay_stats); } -static void update_clock(struct clock *clock, - int64_t offset, uint64_t ts, int64_t delay) +static void update_clock(struct clock *clock, clockid_t src, + int64_t offset, uint64_t ts, int64_t delay, + int do_leap) { enum servo_state state; double ppb; - if (update_sync_offset(clock, offset, ts)) + if (clock_handle_leap(clock, src, offset, ts, do_leap)) return; if (clock->sync_offset_direction) @@ -268,6 +271,7 @@ static int do_pps_loop(struct clock *clock, int fd, { int64_t pps_offset, phc_offset, phc_delay; uint64_t pps_ts, phc_ts; + int do_leap; clock->source_label = "pps"; @@ -304,7 +308,10 @@ static int do_pps_loop(struct clock *clock, int fd, pps_offset = pps_ts - phc_ts; } - update_clock(clock, pps_offset, pps_ts, -1); + do_leap = update_sync_offset(clock); + if (do_leap <= 0) + continue; + update_clock(clock, src, pps_offset, pps_ts, -1, do_leap); } close(fd); return 0; @@ -316,6 +323,7 @@ static int do_sysoff_loop(struct clock *clock, clockid_t src, uint64_t ts; int64_t offset, delay; int err = 0, fd = CLOCKID_TO_FD(src); + int do_leap; clock->source_label = "sys"; @@ -325,7 +333,10 @@ static int do_sysoff_loop(struct clock *clock, clockid_t src, err = -1; break; } - update_clock(clock, offset, ts, delay); + do_leap = update_sync_offset(clock); + if (do_leap <= 0) + continue; + update_clock(clock, src, offset, ts, delay, do_leap); } return err; } @@ -335,6 +346,7 @@ static int do_phc_loop(struct clock *clock, clockid_t src, { uint64_t ts; int64_t offset, delay; + int do_leap; clock->source_label = "phc"; @@ -344,7 +356,10 @@ static int do_phc_loop(struct clock *clock, clockid_t src, &offset, &ts, &delay)) { continue; } - update_clock(clock, offset, ts, delay); + do_leap = update_sync_offset(clock); + if (do_leap <= 0) + continue; + update_clock(clock, src, offset, ts, delay, do_leap); } return 0; } @@ -495,10 +510,19 @@ static void close_pmc(struct clock *clock) clock->pmc = NULL; } -static int update_sync_offset(struct clock *clock, int64_t offset, uint64_t ts) +/* Returns: -1 in case of error, 0 for normal sync, 1 to leap clock */ +static int update_sync_offset(struct clock *clock) { + struct timespec tp; + uint64_t ts; int clock_leap; + if (clock_gettime(CLOCK_REALTIME, &tp)) { + pr_err("failed to read clock: %m"); + return -1; + } + ts = tp.tv_sec * NS_PER_SEC + tp.tv_nsec; + if (clock->pmc && !(ts > clock->pmc_last_update && ts - clock->pmc_last_update < PMC_UPDATE_INTERVAL)) { @@ -511,9 +535,28 @@ static int update_sync_offset(struct clock *clock, int64_t offset, uint64_t ts) if (!clock->leap && !clock->leap_set) return 0; + clock_leap = leap_second_status(ts, clock->leap_set, + &clock->leap, &clock->sync_offset); + if (clock->leap_set != clock_leap) { + clock->leap_set = clock_leap; + return 1; + } + return 0; +} + +/* Returns: non-zero to skip clock update */ +static int clock_handle_leap(struct clock *clock, clockid_t src, + int64_t offset, uint64_t ts, int do_leap) +{ + if (!clock->leap && !do_leap) + return 0; + + if (clock->clkid != CLOCK_REALTIME && src != CLOCK_REALTIME) + return 0; + /* If the system clock is the master clock, get a time stamp from it, as it is the clock which will include the leap second. */ - if (clock->clkid != CLOCK_REALTIME) { + if (src == CLOCK_REALTIME) { struct timespec tp; if (clock_gettime(CLOCK_REALTIME, &tp)) { pr_err("failed to read clock: %m"); @@ -533,17 +576,13 @@ static int update_sync_offset(struct clock *clock, int64_t offset, uint64_t ts) /* Suspend clock updates in the last second before midnight. */ if (is_utc_ambiguous(ts)) { pr_info("clock update suspended due to leap second"); - return -1; + return 1; } - clock_leap = leap_second_status(ts, clock->leap_set, - &clock->leap, &clock->sync_offset); - - if (clock->leap_set != clock_leap) { + if (do_leap) { /* Only the system clock can leap. */ if (clock->clkid == CLOCK_REALTIME && clock->kernel_leap) - sysclk_set_leap(clock_leap); - clock->leap_set = clock_leap; + sysclk_set_leap(clock->leap_set); } return 0;