.flags = CLOCK_SOURCE_IS_CONTINUOUS,
.mask = CLOCKSOURCE_MASK(64),
.read = timebase_read,
+ .vdso_clock_mode = VDSO_CLOCKMODE_ARCHTIMER,
};
#define DECREMENTER_DEFAULT_MAX 0x7FFFFFFF
struct pt_regs *old_regs;
u64 now;
- /* Some implementations of hotplug will get timer interrupts while
- * offline, just ignore these and we also need to set
- * decrementers_next_tb as MAX to make sure __check_irq_replay
- * don't replay timer interrupt when return, otherwise we'll trap
- * here infinitely :(
+ /*
+ * Some implementations of hotplug will get timer interrupts while
+ * offline, just ignore these.
*/
if (unlikely(!cpu_online(smp_processor_id()))) {
- *next_tb = ~(u64)0;
set_dec(decrementer_max);
return;
}
return (u64)get_tb();
}
-
-void update_vsyscall(struct timekeeper *tk)
-{
- struct timespec64 xt;
- struct clocksource *clock = tk->tkr_mono.clock;
- u32 mult = tk->tkr_mono.mult;
- u32 shift = tk->tkr_mono.shift;
- u64 cycle_last = tk->tkr_mono.cycle_last;
- u64 new_tb_to_xs, new_stamp_xsec;
- u64 frac_sec;
-
- if (clock != &clocksource_timebase)
- return;
-
- xt.tv_sec = tk->xtime_sec;
- xt.tv_nsec = (long)(tk->tkr_mono.xtime_nsec >> tk->tkr_mono.shift);
-
- /* Make userspace gettimeofday spin until we're done. */
- ++vdso_data->tb_update_count;
- smp_mb();
-
- /*
- * This computes ((2^20 / 1e9) * mult) >> shift as a
- * 0.64 fixed-point fraction.
- * The computation in the else clause below won't overflow
- * (as long as the timebase frequency is >= 1.049 MHz)
- * but loses precision because we lose the low bits of the constant
- * in the shift. Note that 19342813113834067 ~= 2^(20+64) / 1e9.
- * For a shift of 24 the error is about 0.5e-9, or about 0.5ns
- * over a second. (Shift values are usually 22, 23 or 24.)
- * For high frequency clocks such as the 512MHz timebase clock
- * on POWER[6789], the mult value is small (e.g. 32768000)
- * and so we can shift the constant by 16 initially
- * (295147905179 ~= 2^(20+64-16) / 1e9) and then do the
- * remaining shifts after the multiplication, which gives a
- * more accurate result (e.g. with mult = 32768000, shift = 24,
- * the error is only about 1.2e-12, or 0.7ns over 10 minutes).
- */
- if (mult <= 62500000 && clock->shift >= 16)
- new_tb_to_xs = ((u64) mult * 295147905179ULL) >> (clock->shift - 16);
- else
- new_tb_to_xs = (u64) mult * (19342813113834067ULL >> clock->shift);
-
- /*
- * Compute the fractional second in units of 2^-32 seconds.
- * The fractional second is tk->tkr_mono.xtime_nsec >> tk->tkr_mono.shift
- * in nanoseconds, so multiplying that by 2^32 / 1e9 gives
- * it in units of 2^-32 seconds.
- * We assume shift <= 32 because clocks_calc_mult_shift()
- * generates shift values in the range 0 - 32.
- */
- frac_sec = tk->tkr_mono.xtime_nsec << (32 - shift);
- do_div(frac_sec, NSEC_PER_SEC);
-
- /*
- * Work out new stamp_xsec value for any legacy users of systemcfg.
- * stamp_xsec is in units of 2^-20 seconds.
- */
- new_stamp_xsec = frac_sec >> 12;
- new_stamp_xsec += tk->xtime_sec * XSEC_PER_SEC;
-
- /*
- * tb_update_count is used to allow the userspace gettimeofday code
- * to assure itself that it sees a consistent view of the tb_to_xs and
- * stamp_xsec variables. It reads the tb_update_count, then reads
- * tb_to_xs and stamp_xsec and then reads tb_update_count again. If
- * 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.
- */
- vdso_data->tb_orig_stamp = cycle_last;
- vdso_data->stamp_xsec = new_stamp_xsec;
- vdso_data->tb_to_xs = new_tb_to_xs;
- vdso_data->wtom_clock_sec = tk->wall_to_monotonic.tv_sec;
- vdso_data->wtom_clock_nsec = tk->wall_to_monotonic.tv_nsec;
- vdso_data->stamp_xtime_sec = xt.tv_sec;
- vdso_data->stamp_xtime_nsec = xt.tv_nsec;
- vdso_data->stamp_sec_fraction = frac_sec;
- vdso_data->hrtimer_res = hrtimer_resolution;
- smp_wmb();
- ++(vdso_data->tb_update_count);
-}
-
-void update_vsyscall_tz(void)
-{
- vdso_data->tz_minuteswest = sys_tz.tz_minuteswest;
- vdso_data->tz_dsttime = sys_tz.tz_dsttime;
-}
-
static void __init clocksource_init(void)
{
struct clocksource *clock = &clocksource_timebase;
sys_tz.tz_dsttime = 0;
}
- vdso_data->tb_update_count = 0;
vdso_data->tb_ticks_per_sec = tb_ticks_per_sec;
/* initialise and enable the large decrementer (if we have one) */
projects / linux-2.6-microblaze.git / blobdiff