Function report

Linux Kernel

v5.5.9

Brick Technologies Co., Ltd

Source Code:kernel\time\ntp.c Create Date:2022-07-28 10:43:18
Last Modify:2020-03-12 14:18:49 Copyright©Brick
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Name:Update (tick_length, tick_length_base, tick_nsec), based* on (tick_usec, ntp_tick_adj, time_freq):

Proto:static void ntp_update_frequency(void)

Type:void

Parameter:Nothing

264  second_length = USER_HZ period (usecs): * NSEC_PER_USEC * USER_HZ << NTP_SCALE_SHIFT
267  second_length += constant (boot-param configurable) NTP tick adjustment (upscaled)
268  second_length += quency offset (scaled nsecs/secs):
270  SHIFTED_HZ period (nsecs): = div_u64 - unsigned 64bit divide with 32bit divisor*@dividend: unsigned 64bit dividend*@divisor: unsigned 32bit divisor* This is the most common 64bit divide and should be used if possible,* as many 32bit archs can optimize this variant better than a full >> NTP_SCALE_SHIFT
271  new_base = div_u64 - unsigned 64bit divide with 32bit divisor*@dividend: unsigned 64bit dividend*@divisor: unsigned 32bit divisor* This is the most common 64bit divide and should be used if possible,* as many 32bit archs can optimize this variant better than a full
277  tick_length += new_base - tick_length_base
278  tick_length_base = new_base
Caller
NameDescribe
ntp_clearp_clear - Clears the NTP state variables
process_adjtimex_modes
__do_adjtimexadjtimex mainly allows reading (and writing, if superuser) of* kernel time-keeping variables. used by xntpd.