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Merge ../linux-2.6

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This commit is contained in:
Paul Mackerras
2006-03-17 12:01:19 +11:00
parent 5164501794 485ff09990
commit 23dd640112
144 changed files with 1111 additions and 606 deletions
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48
arch/powerpc/kernel/time.c
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@@ -503,9 +503,9 @@ static inline void update_gtod(u64 new_tb_stamp, u64 new_stamp_xsec,
* the two values of tb_update_count match and are even then the
* tb_to_xs and stamp_xsec values are consistent. If not, then it
* loops back and reads them again until this criteria is met.
* We expect the caller to have done the first increment of
* vdso_data->tb_update_count already.
*/
++(vdso_data->tb_update_count);
smp_wmb();
vdso_data->tb_orig_stamp = new_tb_stamp;
vdso_data->stamp_xsec = new_stamp_xsec;
vdso_data->tb_to_xs = new_tb_to_xs;
@@ -530,20 +530,15 @@ static __inline__ void timer_recalc_offset(u64 cur_tb)
unsigned long offset;
u64 new_stamp_xsec;
u64 tlen, t2x;
u64 tb, xsec_old, xsec_new;
struct gettimeofday_vars *varp;
if (__USE_RTC())
return;
tlen = current_tick_length();
offset = cur_tb - do_gtod.varp->tb_orig_stamp;
if (tlen == last_tick_len && offset < 0x80000000u) {
/* check that we're still in sync; if not, resync */
struct timeval tv;
__do_gettimeofday(&tv, cur_tb);
if (tv.tv_sec <= xtime.tv_sec &&
(tv.tv_sec < xtime.tv_sec ||
tv.tv_usec * 1000 <= xtime.tv_nsec))
return;
}
if (tlen == last_tick_len && offset < 0x80000000u)
return;
if (tlen != last_tick_len) {
t2x = mulhdu(tlen << TICKLEN_SHIFT, ticklen_to_xs);
last_tick_len = tlen;
@@ -552,6 +547,21 @@ static __inline__ void timer_recalc_offset(u64 cur_tb)
new_stamp_xsec = (u64) xtime.tv_nsec * XSEC_PER_SEC;
do_div(new_stamp_xsec, 1000000000);
new_stamp_xsec += (u64) xtime.tv_sec * XSEC_PER_SEC;
++vdso_data->tb_update_count;
smp_mb();
/*
* Make sure time doesn't go backwards for userspace gettimeofday.
*/
tb = get_tb();
varp = do_gtod.varp;
xsec_old = mulhdu(tb - varp->tb_orig_stamp, varp->tb_to_xs)
+ varp->stamp_xsec;
xsec_new = mulhdu(tb - cur_tb, t2x) + new_stamp_xsec;
if (xsec_new < xsec_old)
new_stamp_xsec += xsec_old - xsec_new;
update_gtod(cur_tb, new_stamp_xsec, t2x);
}
@@ -800,6 +810,10 @@ int do_settimeofday(struct timespec *tv)
}
#endif
/* Make userspace gettimeofday spin until we're done. */
++vdso_data->tb_update_count;
smp_mb();
/*
* Subtract off the number of nanoseconds since the
* beginning of the last tick.
@@ -961,10 +975,16 @@ void __init time_init(void)
* It is computed as:
* ticklen_to_xs = 2^N / (tb_ticks_per_jiffy * 1e9)
* where N = 64 + 20 - TICKLEN_SCALE - TICKLEN_SHIFT
* so as to give the result as a 0.64 fixed-point fraction.
* which turns out to be N = 51 - SHIFT_HZ.
* This gives the result as a 0.64 fixed-point fraction.
* That value is reduced by an offset amounting to 1 xsec per
* 2^31 timebase ticks to avoid problems with time going backwards
* by 1 xsec when we do timer_recalc_offset due to losing the
* fractional xsec. That offset is equal to ppc_tb_freq/2^51
* since there are 2^20 xsec in a second.
*/
div128_by_32(1ULL << (64 + 20 - TICKLEN_SCALE - TICKLEN_SHIFT), 0,
tb_ticks_per_jiffy, &res);
div128_by_32((1ULL << 51) - ppc_tb_freq, 0,
tb_ticks_per_jiffy << SHIFT_HZ, &res);
div128_by_32(res.result_high, res.result_low, NSEC_PER_SEC, &res);
ticklen_to_xs = res.result_low;