Messages in this thread | | | Date | Sat, 25 Oct 2014 17:12:48 +0200 (CEST) | From | Thomas Gleixner <> | Subject | Re: [PATCH v5] timekeeping: Added a function to return tv_sec portion of ktime_get_ts64() |
| |
On Sat, 25 Oct 2014, Heena Sirwani wrote: > +time64_t ktime_get_seconds(void) > +{ > + time64_t ts; > + struct timekeeper *tk = &tk_core.timekeeper; > + struct timespec64 tomono; > + s32 nsec; > + unsigned int seq; > + > + WARN_ON(timekeeping_suspended); > + > + do { > + seq = read_seqcount_begin(&tk_core.seq); > + ts = tk->xtime_sec; > + nsec = (long)(tk->tkr.xtime_nsec >> tk->tkr.shift); > + tomono = tk->wall_to_monotonic; > + > + } while (read_seqcount_retry(&tk_core.seq, seq)); > + > + ts += tomono.tv_sec; > + if (nsec + tomono.tv_nsec >= NSEC_PER_SEC) > + ts += 1; > + return ts;
I'd rather have an extra field in the timekeeper
u64 xtime_sec; + u64 ktime_sec;
and update this in tk_update_ktime_data() so the readout function boils down to
time64_t ktime_get_seconds(void) { #if BITS_PER_LONG < 64 u64 sec; int seq;
do { seq = read_seqcount_begin(&tk_core.seq); sec = tk->ktime_sec; } while (read_seqcount_retry(&tk_core.seq, seq));
return sec; #else return tk->ktime_sec; #endif }
So 64bit can do w/o the seqcount and 32bit avoids all extra math, right?
Thanks,
tglx
| |